bluuebunny/crossref_metadata_2025 huggingface dataset:
Purification and characterisation of endo-β-1,4-glucanase and laminarinase enzymes from the gecarcinid land crab Gecarcoidea natalis and the aquatic crayfish Cherax destructor
Authors: Allardyce Benjamin J. , Linton Stuart M.
Published: June 2008

Laminarinase and endo-β-1,4-glucanase were purified and characterised from the midgut gland of the herbivorous land crab Gecarcoidea natalis and the crayfish Cherax destructor. The laminarinase isolated from G. natalis was estimated to have a molecular mass of 41 kDa by SDS-PAGE and 71 kDa by gel filtration chromatography. A similar discrepancy was noted for C. destructor. Possible reasons for this are discussed. Laminarinase (EC 3.2.1.6) from G. natalis had a Vmax of 42.0 μmol reducing sugars produced min–1 mg protein–1, a Kmof 0.126% (w/v) and an optimum pH range of 5.5–7, and hydrolysed mainlyβ-1,3-glycosidic bonds. In addition to the hydrolysis ofβ-1,3-glycosidic bonds, laminarinase (EC 3.2.1.39) from C. destructor was capable of significant hydrolysis of β-1,4-glycosidic bonds. It had a Vmax of 19.6 μmol reducing sugars produced min–1 mg protein–1, a Km of 0.059% (w/v) and an optimum pH of 5.5. Laminarinase from both species produced glucose and other short oligomers from the hydrolysis of laminarin. Endo-β-1,4-glucanase (EC 3.2.1.4) from G. natalis had a molecular mass of 52 kDa and an optimum pH of 4–7. It mainly hydrolysed β-1,4-glycosidic bonds, but was also capable of significant hydrolysis of β-1,3-glycosidic bonds. Two endo-β-1,4-glucanases, termed 1 and 2, with respective molecular masses of 53±3 and 52 kDa, were purified from C. destructor. Endo-β-1,4-glucanase 1 was only capable of hydrolysingβ-1,4-glycosidic bonds and had an optimum pH of 5.5. Endo-β-1,4-glucanases from both species produced some glucose, cellobiose and other short oligomers from the hydrolysis of carboxymethyl cellulose.
Stable carbon isotopes in exhaled breath as tracers for dietary information in birds and mammals
Authors: Voigt Christian C. , Baier Leonie , Speakman John R. , Siemers Björn M.
Published: June 2008

The stable carbon isotope ratio of exhaled CO2(δ13Cbreath) reflects the isotopic signature of the combusted substrate and is, therefore, suitable for the non-invasive collection of dietary information from free-ranging animals. However,δ 13Cbreath is sensitive to changes in ingested food items and the mixed combustion of exogenous and endogenous substrates. Therefore, experiments under controlled conditions are pivotal for the correct interpretation of δ13Cbreath of free-ranging animals. We measured δ13Cbreath in fasted and recently fed insectivorous Myotis myotis (Chiroptera) to assess the residence time of carbon isotopes in the pool of metabolized substrate, and whether δ13Cbreath in satiated individuals levels off at values similar to the dietary isotope signature(δ13Cdiet) in insect-feeding mammals. Meanδ 13Cbreath of fasted individuals was depleted by–5.8‰ (N=6) in relation toδ 13Cdiet. After feeding on insects, bats exchanged 50% of carbon atoms in the pool of metabolized substrates within 21.6±10.5 min, which was slower than bats ingesting simple carbohydrates. After 2 h, δ13Cbreath of satiated bats levelled off at –2.6‰ belowδ 13Cdiet, suggesting that bats combusted both exogenous and endogenous substrate at this time. A literature survey revealed that small birds and mammals metabolize complex macronutrients at slower rates than simple macronutrients. On average, δ13Cbreathof fasting birds and mammals was depleted in 13C by–3.2±2.0‰ in relation toδ 13Cdiet. δ13Cbreathof satiated animals differed by –0.6±2.3‰ fromδ 13Cdiet when endogenous substrates were not in isotopic equilibrium with exogenous substrates and by +0.5±1.8‰(N=6 species) after endogenous substrates were in isotopic equilibrium with exogenous substrates.
Thermal biology of the deep-sea vent annelidParalvinella grasslei:in vivostudies
Authors: Cottin Delphine , Ravaux Juliette , Léger Nelly , Halary Sébastien , Toullec Jean-Yves , Sarradin Pierre-Marie , Gaill Françoise , Shillito Bruce
Published: June 2008

The annelid Paralvinella grasslei is a deep-sea vent endemic species that colonizes the wall of active chimneys. We report here the first data on its thermal biology based on in vivo experiments in pressurized aquaria. Our results demonstrate that P. grassleisurvives a 30 min exposure at 30°C, and suggest that the upper thermal limit of this species is slightly above this temperature. The first signs of stress were noticed at 30°C, such as a significant increase in the animal's activity and the expression of HSP70 stress proteins. A preliminary investigation of the kinetics of stress protein expression surprisingly showed high levels of HSP70 proteins as late as 3.5 h after the heat shock. Finally,we provide here the first sequences for vent annelid hsp70 (P. grasslei, Hesiolyra bergi and Alvinella pompejana). These constitute valuable tools for future studies on the thermal biology of these annelids.
Book Reviews
Authors: Lev Benjamin
Published: June 2008

In Book Reviews, we review an extensive and diverse range of books. They cover theory and applications in operations research, statistics, management science, econometrics, mathematics, computers, and information systems. In addition, we include books in other fields that emphasize technical applications. However, we do not review software. To submit a book for review, please send it to me at the above address. Although we cannot review all books because of space limitations, we do list all books that we receive. We commission all book reviews and do not accept unsolicited reviews. To become a reviewer, please send me your name, address, and specific areas of expertise. We encourage readers to suggest books for review or to ask publishers to send copies of such books.

The authors or editors of books we review in this issue are Jeffrey W. Herrmann, Cheng Hsu, Zbigniew Michalewicz, Martin Schmidt, Matthew Michalewicz, Constantin Chiriac, Wil Michiels, Emile Aarts, Jan Korst, Jeffrey Pfeffer, and Robert I. Sutton.
Structuring and Sustaining Excellence in Management Science at Merrill Lynch
Authors: Nigam Raj
Published: June 2008

The Management Science Group at Merrill Lynch Private Client has had a huge monetary impact at Merrill Lynch and has influenced executive strategies, tactics, and policies. It has also been recognized internationally with several coveted professional awards. This paper examines the underlying structural aspects that led to such excellence and business impact. Behind these successes lies a thoughtful approach that is keenly focused on following a set of core values, viewing and treating people with respect, and practicing disciplined and structured processes. Of these, we value the people as the most important dimension; therefore, we give our analysts the time and freedom to self-actualize—to excel in their own way. We promote such excellence at the individual level and encourage it to spill over to the business side with huge business successes and impact. We show the “how-to”—how we can structure for excellence and sustain it.
The “Killer Application” of Revenue Management: Harrah's Cherokee Casino & Hotel
Authors: Metters Richard , Queenan Carrie , Ferguson Mark , Harrison Laura , Higbie Jon , Ward Stan , Barfield Bruce , Farley Tammy , Kuyumcu H. Ahmet , Duggasani Amar
Published: June 2008

Harrah's Cherokee Casino & Hotel is an unusual example of the use of revenue-management (RM) techniques. Typical RM installations yield revenue improvements of between 3 and 7 percent. The Harrah chain has seen 15-percent improvements, with Harrah's Cherokee Casino & Hotel as the largest beneficiary—although it does not serve alcohol or have traditional table games. In addition, the RM techniques that the Cherokee uses, such as its pricing decisions and customer-segmentation rules, are different from those used in RM applications in other industries.
Prevalence of Abdominal Aortic Aneurysms in Over 65-Year-Old Men with Inguinal Hernias
Authors: Anderson Oliver , Shiralkar Sandy
Published: June 2008

INTRODUCTION

The aim of this study was to determine the prevalence of abdominal aortic aneurysms (AAAs) in over 65-year-old men who have inguinal hernias and discuss if pre-operative selective screening of this population is appropriate.

PATIENTS AND METHODS

A prospective study on 70 consecutive male patients with an age range of 65–88 years (mean, 74 years) who were referred to a single vascular consultant's out-patient clinic with an inguinal hernia were screened for the presence of an AAA with an ultrasound scan before hernia repair over a period of 3 years.

RESULTS

Two patients were found to have an AAA measuring 3.8 cm and 6.0 cm giving an AAA prevalence of 3% (exact 95% confidence interval = 0–10%).

CONCLUSIONS

This study does not demonstrate an increased AAA prevalence in over 65-year-old male patients with inguinal hernias, scanned pre-operatively when compared to screening programmes. Selective screening of this cohort cannot be justified on this evidence.
Sinus Excision, Release of Coccycutaneous Attachments and Dermal-Subcuticular Closure (XRD Procedure): A Novel Technique in Flattening the Natal Cleft in Pilonidal Sinus Treatment
Authors: Marzouk Deya M , Abou-Zeid Ahmed A , Antoniou Anthony , Haji Amyn , Benziger H
Published: June 2008

INTRODUCTION

The objective of this study was to analyse, prospectively, the outcome of a new technique – excision of pilonidal sinus and flattening the natal cleft by division of the coccycutaneous attachments at the lower end of the incision.

PATIENTS AND METHODS

Sixty-six consecutive patients with chronic pilonidal sinuses were treated between 1995 and 2001. The procedure consisted of an elliptical, wide, local excision, release of the coccycutaneous attachments and primary closure using dermal-subcuticular closure (XRD). Suction drains were used until drainage was minimal. The height of skin level at the lower angle of the wound from the coccyx was measured intra-operatively before and after division of the coccycutaneous attachments. Postoperatively, patients were assessed for hospital stay, return to normal activity, complications and recurrence.

RESULTS

Sixty-four patients (97%) were males, median age 27 years. The height of skin level rose from a mean of 1.8 cm (95% CI, 1.78–1.85) to a mean of 3.8 cm (95% CI, 3.77–3.88; P < 0.001). Morbidity affected 12 patients (18%), epidermal separation of the lower wound angles (6 patients), seromas (5 patients) and 1 wound dehiscence at 2 weeks. All other wounds healed primarily without dehiscence. There were no recurrences after a median follow-up of 22.5 months (range, 12–38 months).

CONCLUSIONS

Release of the coccycutaneous attachments is an easy technique to learn, which seems to be an effective way of flattening the natal cleft and may result in lower recurrence rate. This technique should be tried in uncomplicated pilonidal sinus disease before more complex procedures are attempted.
The ‘Parent's Kiss’: An Effective Way to Remove Paediatric Nasal Foreign Bodies
Authors: Purohit Neeraj , Ray Shalina , Wilson Tom , Chawla OP
Published: June 2008

INTRODUCTION

The objectives of this study were to: (i) evaluate the effectiveness of ‘parent's kiss’ as a technique for removal of nasal foreign bodies in children; and (ii) determine whether this technique reduces the number of children requiring general anaesthesia for their removal.

PATIENTS AND METHODS

This was a prospective observational study in the accident and emergency and ENT departments at Luton and Dunstable Hospital. The participants were 31 children with nasal foreign bodies, under the age of 5 years, presenting via the acute services over a 6-month period. The primary outcome measured was successful removal of nasal foreign body with the ‘parent's kiss’ technique. Secondary outcome was reduction in the number of general anaesthetics following introduction of the technique.

RESULTS

The technique was successful in 20 out of the 31 children (64.5%) in the study group. Only one patient required general anaesthesia for removal of nasal foreign body (3%). This compares with a rate of 32.5% requiring removal under general anaesthetic in the preceding 6-month period. The ‘parent's kiss’, when not successful, seemed to improve the visibility of the foreign body making their subsequent removal easier.

CONCLUSIONS

The ‘parent's kiss’ is an effective technique. It is non-traumatic, both physically and emotionally, for the child subjected to it. We advocate that it should be used routinely as a first line of management in children with a nasal foreign body in the primary care setting.
Redefining Urological History Taking – Anal Intercourse as the Cause of Unexplained Symptoms in Heterosexuals
Authors: Coull Nadine , Mastoroudes Heleni , Popert Rick , O'Brien Timothy S
Published: June 2008

INTRODUCTION

Symptoms suggestive of genito-urinary infection are frequent reasons for visits to general practitioners and account for approximately 15% of referrals to out-patient urology. The symptoms may be non-specific, and patients can undergo multiple investigations in an attempt to identify a cause.

PATIENTS AND METHODS

We have seen several such patients, all of whom had engaged in unprotected heterosexual anal intercourse prior to the onset of their symptoms. Presenting complaints included urethral discomfort, acute epididymitis resistant to standard antibiotics, and sudden onset of overactive bladder symptoms.

RESULTS

These patients illustrate the importance of careful history taking. Whilst some questions may be difficult to ask, they may reveal precipitating factors that the patient will be reluctant to volunteer. The repetitive nature of the behaviour may explain the chronicity of symptoms experienced by the patients, and avoidance of this activity may be the only management needed to improve them. For those with infective symptoms, the clinician's choice of antibiotic can be altered to provide anaerobic cover.

CONCLUSIONS

A history of anal intercourse should be sought in patients with unexplained genito-urinary symptoms.
Perception of Abnormal Serum Prostate-Specific Antigen (PSA) Test Results amongst Family Practitioners
Authors: Rochester MA , Donaldson PJ , McLoughlin J
Published: June 2008

INTRODUCTION

With increased use of serum prostate-specific antigen (PSA) testing, prostate cancers are diagnosed at an earlier stage in younger men, when radical curative treatments are appropriate. Modifications of the PSA test such as PSA velocity and age-adjusted values are available to aid in the selection of patients for biopsy. However, it is not clear whether these data are used in general practice.

PATIENTS AND METHODS

A self-administered questionnaire was mailed to all primary care practices within one region in the UK. A series of visual analogue questions designed to identify referral thresholds for age-adjusted PSA levels and PSA velocity were used to identify patterns in referral behaviour.

RESULTS

Individual family practitioners see only small numbers of patients requesting PSA tests or with newly diagnosed prostate cancer each year. The median (range) thresholds considered for referral at ages 45, 55, 65, 75 and 85 years were 4.5 ng/ml (2.5–15.5 ng/ml), 5.5 ng/ml (3.0–15.5 ng/ml), 6.5 ng/ml (3.5–15.5 ng/ml), 6.5 ng/ml (3.5–25.5 ng/ml), and 7.5 ng/ml (3.5–25.5 ng/ml), respectively. Only 5% of practitioners correctly identified the age-specific PSA threshold for referral of a 45-year-old man.

CONCLUSIONS

It is important to remember that younger men (even those in their forties and fifties) may be at risk of prostate cancer even if asymptomatic. It is important in a climate of increasing demand for PSA testing that those who initiate the process understand the implications and limitations of testing, including appropriate triggers for referral to secondary care. The exact approach required for the successful dissemination of this information to primary care is not clear, but our data suggest that a better understanding is required.
Adherence to Recommendations Designed to Decrease Intra-Operative Wound Contamination
Authors: Mackain-Bremner Alice A , Owens Kate , Wylde Vikki , Bannister Gordon C , Blom Ashley W
Published: June 2008

INTRODUCTION

The incidence of wound infection following total hip and knee arthroplasty has fallen with the introduction of laminar vertical laminar airflow, occlusive clothing and prophylactic antibiotics. However, infection still occurs after prosthetic joint replacement and can have devastating consequences. Intra-operative wound contamination is the major source of infection. Measures proven to decrease intra-operative wound contamination include chlorhexidine lavage, removal of jewellery, covering old jewellery, ears, nose, mouth and hair and wearing theatre clothing in an occlusive manner.

PATIENTS AND METHODS

Posters explaining this practice were placed at eye level in the scrub area of orthopaedic theatres and adoption of these techniques was observed covertly before and after.

RESULTS

Eighty-two personnel were audited before the poster was erected and 90 afterwards. Only 2 of 12 observed standards were adhered to 100% of the time.

CONCLUSIONS

Education by posters did not significantly improve adherence to protocols. Compliance with protocols was worse amongst non-scrubbed theatre personnel.
Removing Symptomatic Gallstones at their First Emergency Presentation
Authors: Anwar Hanny A , Ahmed Qamar A , Bradpiece Howard A
Published: June 2008

INTRODUCTION

Early operations for symptomatic gallstones are gaining favour as the complication rate is thought to be lower and it reduces the overall morbidity. This study was performed to clarify how frequently early operations were being performed and what benefits resulted.

PATIENTS AND METHODS

Case notes of 171 patients who underwent laparoscopic cholecystectomy at Princess Alexandra Hospital Harlow were retrospectively reviewed. They were grouped according to their initial diagnosis (cholelithiasis, acute cholecystitis) and the delay to surgery (early, interval). Forty-one cases were excluded as they either had incomplete notes or the initial diagnosis was a different manifestation of gallstones such as pancreatitis. Those receiving interval operations were then grouped according to the mode of their initial presentation. A total of 130 case notes were analysed.

RESULTS

The delay for an interval operation was 3–6 months compared with less than 2 weeks for early operations. Of patients with acute cholecystitis, 43% had early operations but only 12% of patients with cholelithiasis. Waiting for interval operations was associated with multiple re-admissions equivalent to an average of one extra presentation to accident and emergency per patient. This was particularly marked if the initial presentation was to accident and emergency rather than out-patients (P = 0.003). Complication rates were also higher in the interval group.

CONCLUSIONS

Early cholecystectomy on the next available list is likely to reduce morbidity and the long-term in-patient burden so should be recommended for all patients presenting as an emergency with symptomatic gallstones.
Non-Attendance at the Colorectal Clinic: A Prospective Audit
Authors: Corfield Lorraine , Schizas Alexis , Williams Andrew , Noorani A
Published: June 2008

INTRODUCTION

Non-attendance in the out-patient department has financial costs for the NHS and clinical implications to the non-attender and those awaiting an appointment. The aim of this audit was to quantify the percentage of non-attenders at colorectal clinics in a UK teaching hospital, assess which factors affected attendance, establish why individuals fail to attend and to implement appropriate change.

PATIENTS AND METHODS

The number of ‘did-not-attend’ patients was recorded initially for 686 appointments. Non-attenders were contacted by post or telephone to ask why this was so. The study was then repeated following telephone reminders to 391 patients due to attend clinic. The ‘did-not-attend’ rates in the two limbs of the completed audit cycle were then compared.

RESULTS

The initial study revealed a ‘did-not-attend’ rate of 21%, with significantly more males than females failing to attend (males, 28.6%; females, 16.9%; P = 0.001). The ‘did-not-attend’ rate was not significantly affected by the day of the week, time of appointment or by the weather. There were 51.7% responses to either the postal or telephone questionnaire regarding non-attendance. Of these, 27.7% did not receive an appointment letter or received it after the appointment. Hospital administration problems were cited as accounting for 34.2% of ‘did-not-attends’. In the post-intervention limb, 87 patients (22%) replied to the reminder telephone call, of whom 9 (10%) cancelled their appointment and 78 (90%) confirmed that they would attend. The ‘did-not-attend’ rate fell to 19.7% although this was not a significant reduction.

CONCLUSIONS

Telephoning patients before their appointments is labour intensive and did not significantly improve the ‘didnot-attend’ rate. Although hospital administration errors account for a significant number of the ‘did-not-attends’, patients also have a responsibility to notify the hospital if they are unable to attend.
Does Limiting Long-Term Follow-Up for Breast Cancer Allow All Referrals to be Seen in 2 Weeks?
Authors: Potter S , Govindarajulu S , Shere M , Braddon F , Turner J , Sahu AK , Cawthorn SJ
Published: June 2008

INTRODUCTION

The UK National Institute for Health and Clinical Excellence (NICE) recommends that breast cancer follow-up should be limited to 2–3 years stating this will ‘release resources’ making it ‘possible for all women with breast symptoms to be seen within 2 weeks’. In 2000, breast cancer follow-up services in North Bristol were redesigned to reflect evidence-based best practice. The aim of this paper is to assess the impact of this policy on numbers of follow-ups, clinic capacity and waiting times.

PATIENTS AND METHODS

Data regarding the numbers of new and follow-up patients seen in breast clinic between January 2000 and December 2005 were collected from the hospital Patient Administration System. New patients were categorised as either ‘routine’ or ‘urgent’ according to ‘2-week wait’ rule guidelines. Median waiting times were calculated for each group and nominal appointment times assigned in an attempt to assess the effect of any changes on clinic capacity.

RESULTS

The number of follow-ups decreased by 33% as a result of the new policy. Numbers of referrals over the same period, however, increased by 14%. Routine referrals declined, but there was a 27% increase in ‘2-week wait’ patients. Waiting times for routine appointments initially decreased in response to reduced follow-up, but then rose as the number of ‘2-week wait’ referrals increased.

CONCLUSIONS

Reducing long-term follow-up is a simple and effective method of increasing clinic capacity but its effects are inadequate and transient in the face of increasing service demand. Additional innovative and creative strategies will be required if all breast patients are to be seen within 2 weeks.
Geology and mineralogy of late miocene clayey sediments in the southeastern part of the Central Anatolian Volcanic Province, Turkey
Authors: Gürel Ali , Kadir Selahattin
Published: June 2008

Late Miocene clayey sediments were deposited in lake-margin and shallow-lake environments of the southeastern Central Anatolian Volcanic Province (CAVP). Yellow to red mudstone, alternating with thin beds of conglomerate and sandstone in the Mustafapaşa Formation, is overlain by altered white Cemilköy ignimbrite. Grain size fines upward in each sequence (conglomerate, sandstone, and mudstone). The occurrence of reddish coloration upward, ripple marks, desiccation cracks, plant rootlets and remnants, and the development of initial-stage paleosols in association with smectite reveal that the area underwent alternating periods of siliciclastic and volcaniclastic sediment supply (wet) and drying. Micromorphologically, the development of spongy smectite in mudstone of the Mustafapaşa Formation and vermiform kaolinite in the Cemilköy ignimbrite on resorbed detrital feldspar and devitrified glass reveals in situ precipitation driven by dissolution and precipitation mechanisms. In addition, alteration of these sediments may have resulted in the depletion of soluble alkaline elements, such as Ca, Na, and K, from the ignimbrite downward into the Mustafapaşa Formation. Alternatively, the leaching of these elements — due to the hydrologically open system of the lake environment — may have resulted in the enhancement of Al+Fe/Si-favored precipitation of kaolinite in an acidic environmental condition, namely, of the altered Cemilköy ignimbrite at the top of the profile of the Mustafapaşa Formation, and of smectite in an alkaline setting within lower-level sediments where carbonate minerals were lacking. The coexistence of smectite with accessory illite indicates that illitization occurred via release of K and Al during excess desorption of feldspar. Large Ni and Co values in mudstone samples, and Fe oxidized and partly chloritized pyroxene and hornblende, indicate that the basin was also affected by ophiolite-related supply.
Na-bearing white micas from Triassic rocks of the transition between the Maláguide and Alpujárride complexes (Betic Cordillera, Spain)
Authors: Ruiz Cruz Maria Dolores
Published: June 2008

The structural significance of micas with Na-K intermediate composition, and their chemical and structural evolution at increasing metamorphic grade have been investigated in Triassic rocks from the transition between the Maláguide and Alpujárride complexes (Internal zones of the Betic Cordillera, Spain). Micas were studied by X-ray diffraction (XRD) and by scanning and transmission electron microscopy (SEM/TEM). Three samples, belonging to the late diagenesis and to the low and medium anchizone, were selected for this study. Na-bearing mica appears as submicroscopic packets intergrown in parallel with K-mica, becoming more compositionally uniform with increasing grade. The diagenetic sample contains illite, minor paragonite, and two main populations of intermediate Na-K micas, with average compositions Ms60Prg40 and Ms35Prg65, respectively, where Ms represents muscovite and Prg, paragonite. The lattice-fringe images of mica packets with intermediate compositions suggest the presence of random mixed-layered paragonite-muscovite. Under low anchizonal conditions the amount of discrete paragonite increases and the Na-K intermediate mica has a mean composition of Ms40Prg60. The TEM images suggest that the packets with intermediate composition are solid solutions of paragonite and illite. Micas with Na-K intermediate composition are lacking in the sample with the highest metamorphic grade. In this sample, paragonite and muscovite coexist with mica, with composition intermediate between paragonite and margarite. The lattice-fringe images of these Na-Ca-bearing packets suggest that they consist of irregularly shaped domains enriched either in Na or in Ca.

Our data indicate that Na+K-bearing micas have several origins: detrital stacks of K- and Na-bearing micas coexist with authigenic phases, formed from dickite in the diagenetic, coarse-grained samples, and perhaps from smectite-bearing mixed-layers or detrital illite, in the fine-grained rocks. The changes observed at increasing metamorphic grade can be related to the influence of the lithology, the metamorphic grade, and the different geological settings. Intermediate Na-Ca mica appears to have grown from paragonite, with calcite as the source of Ca.
Early clay diagenesis in Gulf Coast sediments: New insights from XRD profile modeling
Authors: McCarty Douglas K. , Sakharov Boris A. , Drits Victor A.
Published: June 2008

Samples from different depths in the Oligocene Frio formation (offshore Gulf of Mexico) were studied by X-ray diffraction (XRD), thermal analyses, and scanning electron microscopy. The experimental XRD patterns recorded from oriented and ethylene glycol (EG) solvated clay fractions of the samples were similar to those typical of random, mixed-layered illite-smectite (R0 I-S). The experimental XRD patterns recorded in air-dried (AD) and EG states were simulated using three different models. One of them corresponds to R0 I-S for which thickness and content of the interstratified layers were determined by the Środoń technique. The second model is represented by a single homogeneous I-S in which illite and smectite layers are interstratified with a tendency to segregation. The expandability of the segregated I-S model varies from 48% to 75% without any rational relationship between the smectite layer content and depth.

The third model assumes that the clay fraction is a physical mixture of smectite and an R0 I-S. In this model the I-S contains 65% illite and 35% smectite layers independent of depth, whereas the smectite content varies from 28% to 63%. This model has consistently smaller profile factors, Rp, for both EG and AD XRD scans compared with the Rp values determined for the other two models.

The mineralogical association, volcanic origin, narrow stratigraphic interval (427 m), and low maximum temperature (42°C) of the studied Frio Formation are considered. These features are completely consistent with the two-phase model and so the segregation model must be rejected. An authigenic origin of the pure smectite and an alternative detrital or authigenic origin of the R0 I-S are discussed.
Log selfsimilarity of continuous soil Particle-size distributions estimated using random multiplicative cascades
Authors: Martín Miguel Ángel , García-Gutiérrez Carlos
Published: June 2008

Particle-size distribution (PSD) is a fundamental soil property usually reported as discrete clay, silt, and sand percentages. Models and methods to effectively generate a continuous PSD from such poor descriptions using another property would be extremely useful to predict and understand in fragmented distributions, which are ubiquitous in nature. Power laws for soil PSDs imply scale invariance (or selfsimilarity), a property which has proven useful in PSD description. This work is based on two novel ideas in modeling PSDs: (1) the concept of selfsimilarity in PSDs; and (2) mathematical tools to calculate fractal distributions for specific soil PSDs using few actual texture data. Based on these ideas, a random, multiplicative cascade model was developed that relies on a regularity of scale invariance called ‘log-selfsimilarity.’ The model allows the estimation of intermediate particle size values from common texture data. Using equivalent inputs, this new modeling approach was checked using soil data and shown to provide greatly improved results in comparison to the selfsimilar model for soil PSD data. The Kolmogorov-Smirnov D-statistic for the log-selfsimilar model was smaller than the selfsimilar model in 92.94% of cases. The average error was 0.74 times that of the selfsimilar model. The proposed method allows measurement of a heterogeneity index, H, defined using Hölder exponents, which facilitates quantitative characterization of soil textural classes. The average H value ranged from 0.381 for silt texture to 0.838 for sandy loam texture, with a variance of <0.034 for all textural classes. The index can also be used to distinguish textures within the same textural class. These results strongly suggest that the model and its parameters might be useful in estimating other soil physical properties and in developing new soil PSD pedotransfer functions. This modeling approach, along with its potential applications, might be extended to fine-grained mineral and material studies.
Perceived responsibility for change as an outcome predictor in cognitive‐behavioural group therapy
Authors: Delsignore Aba , Carraro Giovanni , Mathier Fabienne , Znoj Hansjörg , Schnyder Ulrich
Published: June 2008

Purpose

The study of control beliefs in psychotherapy research has been neglected in the past years. Based on the evidence that some patients do not benefit enough from therapy because of inadequate expectancies regarding the responsibility and the mechanisms of therapeutic change, assessing control beliefs specific to the psychotherapy context and linking them to therapy outcome can help highlighting this specific aspect and reactivating a neglected field of clinical research.

Method

Using a new validated instrument (Questionnaire on Control Expectancies in Psychotherapy, TBK), this study investigated whether and how perceived responsibility for change predicts favourable response to group cognitive‐behavioural therapy in a sample of 49 outpatients with social anxiety disorder (SAD). Patient engagement and therapy‐related self‐efficacy were assessed as possible process variables.

Results

Among therapy‐related control beliefs, low powerful others expectancies (towards the therapist) were found to be the strongest predictor for clinical improvement at follow‐up. At a process level, analyses of mediation showed that powerful others expectancies predicted therapy engagement, which then influenced the degree of clinical improvement on social anxiety levels and global symptoms. The association between therapy‐specific internality and outcome was confirmed for social anxiety at follow‐up and was partially mediated by therapy‐related self‐efficacy.

Conclusions

Findings confirm that therapy‐related control beliefs predict psychotherapy process (patient engagement and therapy‐specific self‐efficacy) and outcome in cognitive‐behavioural group therapy for SAD. Implications for clinicians and for future research are discussed.
Low rates of PTSD in men attending childbirth: A preliminary study
Authors: Bradley Rachel , Slade Pauline , Leviston Angela
Published: June 2008

Objectives

To investigate whether men experience symptoms of post‐traumatic stress disorder (PTSD) after attending their partner's labour and delivery and the prevalence and predictors of symptoms of PTSD, anxiety, and depression.

Design

This quantitative study involved a large sample, within‐participants design with questionnaires completed at recruitment and six weeks follow‐up.

Methods

Within 72 hours of attending their partner giving birth, 199 men provided demographic details and completed questions about their partner's pregnancy, labour and delivery. Six weeks later they completed a second questionnaire booklet containing measures of symptoms of post‐traumatic stress, anxiety, and depression.

Results

No men reported symptoms at significant levels on all three dimensions of PTSD (intrusions, avoidance, and hyperarousal) although 12% reported clinically significant symptoms on at least one dimension. The dimension with the highest frequency was hyperarousal. Linear regression indicated more PTSD symptoms were predicted by trait anxiety, fewer children, the pregnancy being unplanned, being present at actual delivery, and feeling less confident about coping, less prepared, and more distressed during the process of childbirth. Prevalence of clinically significant symptoms of depression and anxiety was 8 and 7%, respectively, and was predicted by higher trait anxiety.

Conclusions

In this sample there was little evidence for the full constellation of PTSD in men attending their partner giving birth. Using a trauma perspective in this context may not be supported. Those symptoms most commonly reported could be viewed primarily as anxiety and were linked with less previous experience of attending childbirth. Attendance at actual delivery was a key predictor of symptoms.
Referential delusions of communication and reality discrimination deficits in psychosis
Authors: Bucci Sandra , Startup Mike , Wynn Paula , Heathcote Andrew , Baker Amanda , Lewin Terry J.
Published: June 2008

Background

There appear to be two kinds of delusion of reference, which vary independently: delusions of observation and delusions of communication. It has been suggested that delusions of communication might derive from an impairment in reality discrimination, though the impairment would be centred on non‐verbal channels in delusions of communication as opposed to verbal channels in auditory hallucinations.

Method

Patients (N = 64) with acute psychotic symptoms were recruited according to a 2 × 2 design: presence versus absence of delusions of communication crossed with presence versus absence of auditory hallucinations. They were presented with 100 brief video clips in which an actor either made a well‐known gesture or an incidental movement, with the clips being obscured by visual noise. For each clip, the patients indicated how confident they were that a gesture was portrayed.

Results

According to a signal detection analysis, all groups showed adequate sensitivity and the groups did not differ in sensitivity, but patients with delusions of communication showed a bias to report gestures which was not shown by patients with hallucinations. A control group of healthy volunteers (N = 57) showed significantly greater sensitivity than the patients and a more conservative bias than patients with delusions of communication.

Conclusions

A bias to report gestures is not part of a general tendency to externalize one's own thoughts but may be the result of a reality discrimination deficit that is specific to delusions of communication. A possible theoretical explanation for such a deficit is discussed.
Cytochrome b5 Expression in Gonadectomy-induced Adrenocortical Neoplasms of the Domestic Ferret (Mustela putorius furo)
Authors: Wagner S. , Kiupel M. , Peterson R. A. , Heikinheimo M. , Wilson D. B.
Published: June 2008

Whereas the adrenal glands of healthy ferrets produce only limited amounts of androgenic steroids, adrenocortical neoplasms that arise in neutered ferrets typically secrete androgens or their derivative, estrogen. The 17,20-lyase activity of cytochrome P450 17α-hydroxylase/17,20-lyase (P450c17) must increase to permit androgen biosynthesis in neoplastic adrenal tissue. We screened ferret adrenocortical tumor specimens for expression of cytochrome b5 (cyt b5), an allosteric regulator that selectively enhances the 17,20-lyase activity of P450c17. Cyt b5 immunoreactivity was evident in 24 of 25 (96%) adrenocortical adenomas/carcinomas from ferrets with signs of ectopic sex steroid production. Normal adrenocortical cells lacked cyt b5, which may account for the low production of adrenal androgens in healthy ferrets. Other markers characteristic of gonadal somatic cells, such as luteinizing hormone receptor, aromatase, and GATA4, were coexpressed with cyt b5 in some of the tumors. We concluded that cyt b5 is upregulated during gonadectomy-induced adrenocortical neoplasia and is a marker of androgen synthetic potential in these tumors.
A Histopathologic and Immunohistochemical Review of Archived UK Caprine Scrapie Cases
Authors: Dustan B. H. , Spencer Y. I. , Casalone C. , Brownlie J. , Simmons M. M.
Published: June 2008

In 2005, a prion disease identified in a goat from France was reported to be consistent with disease from the bovine spongiform encephalopathy (BSE) agent. Subsequent retrospective examination of UK goat scrapie cases led to the identification of one potentially similar, but as yet unconfirmed, case from Scotland. These findings strengthened concerns that small ruminant populations exposed to the BSE agent have become infected. The lack of data relating specifically to scrapie in goats has been contributory to past assumptions that, in general, sheep and goats respond similarly to prion infections. In this study, brain material from 22 archived caprine scrapie cases from the UK was reviewed by histopathology and by immunohistochemical examination for accumulations of disease-specific prion protein (PrPSc) to provide additional data on the lesions of caprine scrapie and to identify any BSE-like features. The vacuolar change observed in the goats was characteristic of transmissible spongiform encephalopathies in general. PrPSc immunohistochemical morphologic forms described in scrapie and experimental BSE infections of sheep were demonstrable in the goats, but these were generally more extensive and variable in PrPSc accumulation. None of the cases examined showed a PrPSc immunohistochemical pattern indicative of BSE.
Complementary Distributions of Amyloid-β and Neprilysin in the Brains of Dogs and Cats
Authors: Takeuchi Y. , Uetsuka K. , Murayama M. , Kikuta F. , Takashima A. , Doi K. , Nakayama H.
Published: June 2008

Neprilysin is an amyloid-β-degrading enzyme localized in the brain parenchyma. The involvement of neprilysin in the pathogenesis of Alzheimer's disease has recently received much attention. We examined the localization of neprilysin and amyloid-β, as well as the activity of neprilysin, in the brains of dogs and cats of various ages to clarify the relationship between neprilysin activity and amyloid-β deposition. The distribution of neprilysin was almost identical in dogs and cats, being high in the striatum, globus pallidus, and substantia nigra, but very low in the cerebral cortex. The white matter and hippocampus were negative. Neprilysin activity in the brain regions in dogs and cats was ranked from high to low as follows: thalamus/striatum > cerebral cortex > hippocampus > white matter. Amyloid-β deposition was first detected at 7 and 10 years of age in dogs and cats, respectively, and both the quantity and frequency of deposition increased with age. In both species, amyloid-β deposition appeared in the cerebral cortex and the hippocampus. In summary, the localization of neprilysin and neprilysin activity, and that of amyloid-β, were complementary in the brains of dogs and cats.
End-Stage Kidney Disease Probably due to Reflux Nephropathy with Segmental Hypoplasia (Ask-Upmark Kidney) in Young Boxer Dogs in Norway. A Retrospective Study
Authors: Kolbjørnsen Ø. , Heggelund M. , Jansen J. H.
Published: June 2008

This paper is a retrospective morphologic study of 7 young Boxer dogs, showing end-stage kidney lesions compatible with chronic pyelonephritis with severe segmental cortical atrophy and fibrosis, associated with chronic tubulointerstitial inflammation of varying degree. Azotemia was observed in 6 of the 7 cases. The gross kidney lesions were as follows: bilateral small kidneys with numerous segmental cortical scars causing depression of the renal cortical surface. Histologic examination revealed salient atrophy of nephrons, including paucity of glomeruli, glomerulocystic lesions, colloid-filled tubular microcysts, and a conspicuously increased occurrence of arteries with narrowed lumina caused by intimal thickening. These segmental abnormalities were accompanied by pronounced interstitial fibrosis. All but 1 dog showed salient tubulointerstitial lympho-plasmacytic infiltration, which in 3 cases also included diffuse infiltration of polymorphonuclear neutrophilic leukocyte (PMN)-cells and occurrence of tubular PMN-casts. Morphologic signs of abnormal metanephric differentiation (renal dysplasia) were observed in all cases in the form of atypical tubules or asynchronous nephronic development (immature glomeruli) or both. However, other morphologic primary dysplastic features were absent. Based on the morphologic features, it is concluded that the end-stage kidney disease in these young Boxer dogs was the result of chronic atrophic nonobstructive pyelonephritis, most probably caused by vesico-ureteral reflux, compatible with reflux nephropathy causing segmental hypoplasia (Ask-Upmark kidney) in man. It is proposed that atypical tubular epithelium in the form of adenomatoid proliferation of collecting duct epithelial cells should be considered an acquired compensatory lesion, rather than the result of disorganized metanephric development.
Hyalinizing Pancreatic Adenocarcinoma in Six Dogs
Authors: Dennis M. M. , O'Brien T. D. , Wayne T. , Kiupel M. , Williams M. , Powers B. E.
Published: June 2008

Exocrine pancreatic carcinoma is a particularly malignant neoplasm of the dog. Clinical and pathologic findings of an unusual variant of exocrine pancreatic neoplasia termed hyalinizing pancreatic adenocarcinoma were evaluated in 6 dogs. On microscopic examination, neoplasms were composed of tubules and acini of epithelial cells, with bright eosinophilic granular apical cytoplasm. Tubular lumina and tumor stroma contained abundant hyaline material that resembled amyloid. The hyaline material was not congophilic, and tumor cells and hyaline material were immunohistochemically negative for amyloid A, immunoglobulin light chains (κ and λ), amylin (islet amyloid polypeptide), laminin, and α1-antitrypsin. Two patients survived longer than 15 months after diagnosis; one of these dogs was untreated and had grossly evident metastasis at the time of diagnosis. The deaths of the other 4 dogs occurred as a result of poor recovery after partial pancreatectomy or in association with other concurrent life-threatening conditions. Two dogs were diagnosed with panniculitis, a condition rarely associated with pancreatic disease. Further evaluation is needed to determine the composition and biologic significance of intratumor hyaline material. Studies that associate exocrine pancreatic carcinoma grade and histologic subtype with prognostic outcomes in the dog are warranted such that appropriate therapy can be elected.
Immunohistochemical Characterization of a Pulmonary Large-Cell Carcinoma in a Dog
Authors: Buendia A. J. , Sánchez J. , Martinez C. M. , Navarro J. A.
Published: June 2008

Primary pulmonary tumors are less common in dogs than secondary (metastatic) tumors. Most primary tumors are malignant and of epithelial origin. Pulmonary large-cell carcinoma is considered extremely rare in domestic animals, and some of the few reported cases actually may have been cases of malignant pulmonary histiocytosis. An 8-year-old female Wire Fox Terrier with diffuse alveolar pattern radiographically was euthanatized when it failed to respond to antibiotic therapy. Histologically, pulmonary alveolar spaces contained clusters of large round anaplastic cells with ample eosinophilic cytoplasm and large irregularly shaped nuclei with prominent nucleoli. Immunohistochemistry was used to distinguish large-cell carcinoma from malignant pulmonary histiocytosis. Tumor cells had strong immunoreactivity for cytokeratin, consistent with epithelial origin. However, a substantial percentage of the neoplastic cells co-expressed vimentin and MHC-II. The type II alveolar epithelial cell was considered the cell of origin of the neoplasm based on the presence of lamellar bodies in some neoplastic cells and immunoreactivity for surfactant protein A and thyroid transcription factor-1.
Metritis, Valvular Endocarditis, and Septicemia by Actinobacillus equuli in a Gilt in the United States
Authors: Ramos-Vara J. A. , Wu C. C. , Mitsui I. , Lin T. L. , Miller M. A.
Published: June 2008

A 1-year-old pregnant Yorkshire gilt was found dead with no previous clinical signs. Gross findings included metritis, splenomegaly, and valvular endocarditis. Bacterial endocarditis (in the mitral and tricuspid valves) and metritis with dissemination to multiple organs was diagnosed by using histologic examination. Gram-negative coccobacillary organisms present in the valvular lesions were characterized as Actinobacillus equuli by using polymerase chain reaction examination on formalin-fixed, paraffin-embedded tissues (FFPE). A. equuli is rarely reported as a cause of septicemia in pigs in Europe. A. equuli in pigs in the United States has been reported only twice and not, to our knowledge, in the last 30 years. This is the first time that molecular techniques have been used to characterize this organism in FFPE porcine tissues.