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1.
Oecologia ; 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38842684

ABSTRACT

Researchers often use trace element concentrations, including strontium-calcium ratios (Sr/Ca), to reconstruct paleodiets. While most commonly used as a proxy for meat consumption, a more appropriate application may be to differentiate frugivory from folivory. Sr/Ca ratios in animal tissue reflect the Sr/Ca ratios of the highest calcium components of that animal's diet. Because plants have much higher concentrations of calcium than meat, meat consumption signals are often overwhelmed by the variation in Sr/Ca ratios coming from different plant parts. This study uses faunal and plant data from Kibale National Park, a protected forest in southwestern Uganda home to numerous primate species (for example, common chimpanzees and baboons), to assess the reliability of Sr/Ca ratios to differentiate between primate dietary groups. We find that leaves consistently have higher strontium and calcium concentrations than fruits and that this is mirrored in higher Sr/Ca ratios in folivorous primates compared to frugivorous primates. Plant species differ widely in both their overall Sr/Ca ratios and the differences between their fruit and leaf Sr/Ca ratios, but this variation does not overwhelm the dietary signal separating frugivores and folivores. Furthermore, this research demonstrates that non-destructive and portable X-ray florescence (XRF) methods are an effective means of gathering Sr/Ca data from plant and faunal material, increasing the opportunities to apply such methods to fossil material in the future.

2.
Proc Biol Sci ; 290(1993): 20221897, 2023 Feb 22.
Article in English | MEDLINE | ID: mdl-36809801

ABSTRACT

The recent collapse of predatory sunflower sea stars (Pycnopodia helianthoides) owing to sea star wasting disease (SSWD) is hypothesized to have contributed to proliferation of sea urchin barrens and losses of kelp forests on the North American west coast. We used experiments and a model to test whether restored Pycnopodia populations may help recover kelp forests through their consumption of nutritionally poor purple sea urchins (Strongylocentrotus purpuratus) typical of barrens. Pycnopodia consumed 0.68 S. purpuratus d-1, and our model and sensitivity analysis shows that the magnitude of recent Pycnopodia declines is consistent with urchin proliferation after modest sea urchin recruitment, and even small Pycnopodia recoveries could generally lead to lower densities of sea urchins that are consistent with kelp-urchin coexistence. Pycnopodia seem unable to chemically distinguish starved from fed urchins and indeed have higher predation rates on starved urchins owing to shorter handling times. These results highlight the importance of Pycnopodia in regulating purple sea urchin populations and maintaining healthy kelp forests through top-down control. The recovery of this important predator to densities commonly found prior to SSWD, whether through natural means or human-assisted reintroductions, may therefore be a key step in kelp forest restoration at ecologically significant scales.


Subject(s)
Asteraceae , Helianthus , Kelp , Strongylocentrotus purpuratus , Animals , Humans , Food Chain , Starfish , Predatory Behavior , Forests , Sea Urchins/physiology , Ecosystem
3.
Biol Bull ; 239(3): 183-188, 2020 12.
Article in English | MEDLINE | ID: mdl-33347796

ABSTRACT

AbstractFor many historical and contemporary experimental studies in marine biology, seawater carbonate chemistry remains a ghost factor, an uncontrolled, unmeasured, and often dynamic variable affecting experimental organisms or the treatments to which investigators subject them. We highlight how environmental variability, such as seasonal upwelling and biological respiration, drive variation in seawater carbonate chemistry that can influence laboratory experiments in unintended ways and introduce a signal consistent with ocean acidification. As the impacts of carbonate chemistry on biochemical pathways that underlie growth, development, reproduction, and behavior become better understood, the hidden effects of this previously overlooked variable need to be acknowledged. Here we bring this emerging challenge to the attention of the wider community of experimental biologists who rely on access to organisms and water from marine and estuarine laboratories and who may benefit from explicit considerations of a growing literature on the pervasive effects of aquatic carbonate chemistry changes.


Subject(s)
Laboratories , Seawater , Carbon Dioxide , Carbonates/analysis , Hydrogen-Ion Concentration , Oceans and Seas
4.
Dis Aquat Organ ; 135(2): 89-95, 2019 Jul 25.
Article in English | MEDLINE | ID: mdl-31342910

ABSTRACT

Negative consequences of parasites and disease on hosts are usually better understood than their multifaceted ecosystem effects. The pathogen Labyrinthula zosterae (Lz) causes eelgrass wasting disease but has relatives that produce large quantities of nutritionally valuable long-chain polyunsaturated fatty acids (LCPUFA) such as docosahexaenoic acid (DHA). Here we quantify the fatty acids (FA) of Lz cultured on artificial media, eelgrass-based media, and eelgrass segments to investigate whether Lz may similarly produce LCPUFA. We also assess whether field-collected lesions show similar FA patterns to laboratory-inoculated eelgrass. We find that Lz produces DHA as its dominant FA along with other essential FA on both artificial and eelgrass-based media. DHA content was greater in both laboratory-inoculated and field-collected diseased eelgrass relative to their respective controls. If Lz's production scales in situ, it may present an unrecognized source of LCPUFA in eelgrass ecosystems.


Subject(s)
Stramenopiles , Animals , Ecosystem , Fatty Acids, Essential
5.
Conserv Physiol ; 7(1): coz011, 2019.
Article in English | MEDLINE | ID: mdl-31110763

ABSTRACT

A strength of physiological ecology is its incorporation of aspects of both species' ecology and physiology; this holistic approach is needed to address current and future anthropogenic stressors affecting elasmobranch fishes that range from overexploitation to the effects of climate change. For example, physiology is one of several key determinants of an organism's ecological niche (along with evolutionary constraints and ecological interactions). The fundamental role of physiology in niche determination led to the development of the field of physiological ecology. This approach considers physiological mechanisms in the context of the environment to understand mechanistic variations that beget ecological trends. Physiological ecology, as an integrative discipline, has recently experienced a resurgence with respect to conservation applications, largely in conjunction with technological advances that extended physiological work from the lab into the natural world. This is of critical importance for species such as elasmobranchs (sharks, skates and rays), which are an especially understudied and threatened group of vertebrates. In 2017, at the American Elasmobranch Society meeting in Austin, Texas, the symposium entitled `Applications of Physiological Ecology in Elasmobranch Research' provided a platform for researchers to showcase work in which ecological questions were examined through a physiological lens. Here, we highlight the research presented at this symposium, which emphasized the strength of linking physiological tools with ecological questions. We also demonstrate the applicability of using physiological ecology research as a method to approach conservation issues, and advocate for a more available framework whereby results are more easily accessible for their implementation into management practices.

6.
Environ Entomol ; 45(6): 1371-1378, 2016 12.
Article in English | MEDLINE | ID: mdl-28028083

ABSTRACT

From 2010 through 2013, adult emergence and seasonality of Laricobius nigrinus Fender, an introduced predatory species native to western North America, as well as hybridization with the native species Laricobius rubidus (LeConte), were evaluated using emergence traps and beat-sheet sampling in areas of previous release against hemlock woolly adelgid, Adelges tsugae Annand. The shortest emergence period of adult L. nigrinus was 7 wk beginning 22 October 2010, and the longest emergence was 15 wk beginning 17 October 2012. Native L. rubidus also were collected from emergence traps placed on the ground surface and beat-sheet samples all 3 yr, with emergence of L. rubidus initiating later than L. nigrinus each season. Seasonality of both Laricobius species was similar across a 44-mo study period. Adult L. nigrinus were present from October through April, and larvae of Laricobius spp. were collected from February to May. The average number of L. nigrinus from emergence traps was significantly greater than the average number of beetles collected from beat-sheet samples in 2010, while the converse was observed during 2012. Hybridization between L. nigrinus and L. rubidus was documented from 10.75% of specimens collected during 2010 and 2011, indicating periodic interbreeding between the introduced and native species. These findings suggest emergence trapping may be a useful method to assess establishment, population densities, and seasonality of Laricobius species in areas of release to enhance their use in management of A. tsuage.


Subject(s)
Coleoptera/physiology , Food Chain , Hemiptera , Seasons , Animals , Coleoptera/genetics , Coleoptera/growth & development , Hemiptera/physiology , Hybridization, Genetic , Larva/growth & development , Larva/physiology , Population Dynamics , Pupa/growth & development , Pupa/physiology , Tennessee
7.
J Virol Methods ; 203: 107-11, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24704349

ABSTRACT

Immunosuppression following solid organ transplantation reduces T cell-mediated immune control of Epstein-Barr Virus (EBV), which may then drive development of post-transplant lymphoproliferative disease. Serology plays a key role in determination of risk of outgrowth of such lesions following transplantation. The study compared the VIDAS(®) (bioMérieux) and LIAISON(®) (DiaSorin) enzyme immunoassays (EIAs) and immunofluorescence assays (IFA; MBL-Bion) in the kidney transplantation setting. Sera from 100 live kidney donors [51 males; age range 20-82 years (mean 51.2 years)] and 100 cadaveric kidney recipients [70 males; age range 17-77 years (mean 51.0 years)] were tested. Overall proportional agreement ranged from 96% to 100% for VIDAS(®) and LIAISON(®). Sensitivity ranged from 91% to 100% and 92% to 100% for VIDAS(®)/IFA and LIAISON(®)/IFA, respectively. The VIDAS(®) and LIAISON(®) approaches gave similar results. Such automated random access EIAs are well suited to busy clinical virology laboratories and rapid determination of donor and recipient EBV serostatus prior to transplantation.


Subject(s)
Antibodies, Viral/blood , Epstein-Barr Virus Infections/diagnosis , Herpesvirus 4, Human/immunology , Kidney Transplantation , Adolescent , Adult , Aged , Aged, 80 and over , Automation, Laboratory/methods , Enzyme-Linked Immunosorbent Assay/methods , Female , Fluorescent Antibody Technique/methods , Humans , Male , Middle Aged , Sensitivity and Specificity , Serologic Tests/methods , Young Adult
8.
J Hosp Infect ; 75(4): 282-6, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20635470

ABSTRACT

A UK-wide audit of the laboratory diagnosis of Clostridium difficile infection (CDI) was undertaken by the Association of Clinical Pathologists and the Royal College of Pathologists, in conjunction with Keele University. A postal questionnaire was sent out to all Consultant Microbiologists, with eighty responses available for analysis. There was considerable variation in laboratory practices. In particular, only 56% of laboratories gave guidance on follow-up testing of toxin-negative samples, 68% provided a 7 day per week diagnostic service and 66% would routinely communicate positive inpatient toxin results to ward nursing or just medical staff. To ensure a consistent approach to the diagnosis of CDI, laboratories require more detailed and prescriptive guidance than is currently available.


Subject(s)
Clinical Laboratory Techniques , Clostridioides difficile/isolation & purification , Clostridium Infections/diagnosis , Medical Audit , Clostridium Infections/microbiology , Humans , State Medicine , Surveys and Questionnaires , United Kingdom
9.
J Clin Pathol ; 63(3): 262-3, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19858530

ABSTRACT

Platelet transfusions have the highest incidence of post-transfusion sepsis compared with any other blood products. Recent reports suggest that platelet-related bacteraemia occurs at a frequency of approximately 50 times greater than that for red blood cells. The source is usually skin contaminants from the donor and several organisms have been implicated, the commonest of which are coagulase-negative staphylococci. This report describes a case of serious Staphylococcus aureus sepsis following platelet transfusion, and discusses relevant methods to detect and prevent bacterial contamination of blood products.


Subject(s)
Bacteremia/microbiology , Cross Infection/transmission , Platelet Transfusion/adverse effects , Staphylococcal Infections/transmission , Adult , Blood Platelets/microbiology , Humans , Male , Myelodysplastic Syndromes/therapy
10.
Appetite ; 52(2): 307-12, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19056439

ABSTRACT

The purpose of this study was to investigate the intra-familial relationships between parental reports of feeding practices used with siblings in the same family, and to evaluate whether differences in feeding practices are related to differences in siblings' eating behaviours. Eighty parents of two sibling children completed measures assessing their feeding practices and child eating behaviours. Parents reported using greater restrictive feeding practices with children who were fussier and desired to drink more than their sibling. Parents reported using more pressure to eat with siblings who were slower to eat, were fussier, emotionally under-ate, enjoyed food less, were less responsive to food, and were more responsive to internal satiety cues. Restriction and pressure to eat appear to be part of the non-shared environment which sibling children experience differently. These feeding practices may be used differently for children in the same family in response to child eating behaviours or other specific characteristics.


Subject(s)
Feeding Behavior , Parent-Child Relations , Psychology, Child , Siblings/psychology , Attitude , Body Weight , Child , Child, Preschool , Choice Behavior , Emotions , Energy Intake , England , Feeding and Eating Disorders/psychology , Female , Humans , Male , Overweight/psychology , Satiety Response , Stress, Psychological , Surveys and Questionnaires
12.
J Antimicrob Chemother ; 62(1): 5-34, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18445577

ABSTRACT

These evidence-based guidelines have been produced after a systematic literature review of a range of issues involving prevention, diagnosis and treatment of hospital-acquired pneumonia (HAP). Prevention is structured into sections addressing general issues, equipment, patient procedures and the environment, whereas in treatment, the structure addresses the use of antimicrobials in prevention and treatment, adjunctive therapies and the application of clinical protocols. The sections dealing with diagnosis are presented against the clinical, radiological and microbiological diagnosis of HAP. Recommendations are also made upon the role of invasive sampling and quantitative microbiology of respiratory secretions in directing antibiotic therapy in HAP/ventilator-associated pneumonia.


Subject(s)
Cross Infection/drug therapy , Cross Infection/prevention & control , Pneumonia, Bacterial/drug therapy , Pneumonia, Bacterial/prevention & control , Anti-Bacterial Agents/therapeutic use , Cross Infection/diagnosis , Humans , Infection Control/methods , Pneumonia, Bacterial/diagnosis , United Kingdom
13.
J Clin Pathol ; 61(6): 773-4, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18326014

ABSTRACT

A rare case of soft tissue infection due to Salmonella Michigan in an immunocompromised child is reported. The same organism was isolated from a tortoise kept in the home. Immunocompromised patients are especially susceptible to reptile-associated salmonellosis and should be advised appropriately.


Subject(s)
Immunocompromised Host , Opportunistic Infections/microbiology , Salmonella Infections/diagnosis , Salmonella enterica , Soft Tissue Infections/microbiology , Animals , Animals, Domestic/microbiology , Child , Humans , Male , Opportunistic Infections/veterinary , Soft Tissue Infections/veterinary , Turtles/microbiology , Zoonoses/transmission
14.
J Clin Pathol ; 61(1): 140-1, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17675537

ABSTRACT

Gram stain of a positive blood culture is the clinician's first indication of a possible causative infective organism and a guide to suitable antimicrobial therapy prior to cultural and phenotypic identification with susceptibility test results. Occasionally interpretation of a Gram stain can be difficult; if there is a low bacterial load, no organisms may be seen. Such a case is reported, where a positive blood culture taken from the Hickman line of an immunocompromised patient flagged as positive at 5 days' incubation, but no organisms were seen on Gram film. On subculture, a slow growing Gram-positive bacillus was isolated which was initially misidentified and reported as a "diphtheroid" species. The actual identity of this organism and further isolates was later elucidated as Mycobacterium mucogenicum, a rapidly growing non-tuberculous mycobacterium.


Subject(s)
Catheterization, Central Venous/instrumentation , Immunocompromised Host , Mycobacterium Infections/diagnosis , Opportunistic Infections/diagnosis , Adolescent , Catheters, Indwelling , Diagnosis, Differential , Diphtheria/diagnosis , Equipment Contamination , Humans , Male , Mycobacterium Infections/immunology , Opportunistic Infections/immunology
15.
Oncogene ; 27(18): 2594-601, 2008 Apr 17.
Article in English | MEDLINE | ID: mdl-17968311

ABSTRACT

The fgf-2 gene encodes low molecular weight (LMW, 18 kDa) and high molecular weight (HMW, 22-24 kDa) forms that originate from alternative translation of a single mRNA and exhibit diverse biological functions. HMW fibroblast growth factor-2 (FGF-2) inhibits cell migration and induces cell transformation or growth arrest in a cell type- and dose-dependent fashion. Conversely, LMW FGF-2 upregulates both cell proliferation and migration in most cell types. Although transcriptional and translational regulation of HMW and LMW FGF-2 has been extensively investigated, little is known about post-translational control of their relative expression. Here we report that thrombin, a key coagulation factor and inflammatory mediator, cleaves HMW FGF-2 into an LMW FGF-2-like form that stimulates endothelial cell migration and proliferation. The effect of thrombin on these cell functions requires HMW FGF-2 cleavage. This post-translational control mechanism adds a novel level of complexity to the regulation of FGF-2, and links the activities of thrombin and FGF-2 in patho-physiological processes in which both molecules are expressed.


Subject(s)
Cell Movement/physiology , Cell Proliferation , Endothelial Cells/metabolism , Fibroblast Growth Factor 2/metabolism , Inflammation Mediators/metabolism , Protein Processing, Post-Translational/physiology , Thrombin/metabolism , Animals , Cell Movement/drug effects , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Endothelial Cells/cytology , Fibroblast Growth Factor 2/pharmacology , Humans , Inflammation Mediators/pharmacology , Mice , Molecular Weight , Thrombin/pharmacology , Transcription, Genetic/physiology
16.
J Psychiatr Ment Health Nurs ; 14(7): 705-12, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17880665

ABSTRACT

Admission to a mental health inpatient setting is one important aspect of care which requires collaborative working between Community Mental Health Teams (CMHTs) and ward staff. However, links are not always formalized. The failure of effective gatekeeping coupled with inconsistent admission and discharge practices further complicates the situation for all those involved. A number of local changes, for example, adoption of a centralized bed bureau, together with policy changes, initiated a nurse-led practice development project. It was predicted that by creating a framework for more formalized communication between the different disciplines admission and discharge processes would be improved, thus enhancing service users' satisfaction and empowering all staff participating in the process. During the project, 132 service users were notified as potentially requiring admission. Admissions were avoided and diverted for 22 of them. The quality of the communication and information shared between the CMHTs and ward staff was significantly improved. Accessing inpatient beds, at times still remained problematic, as beds could only remain ring-fenced on 65% of occasions. This initiative, conducted within a 'real world setting', showed that it is possible to improve admission and discharge practices by creating a framework for a formalized communication process between disciplines.


Subject(s)
Mental Disorders/epidemiology , Mental Disorders/therapy , Mental Health Services , Motivation , Nurses , Patient Admission/statistics & numerical data , Adult , Female , Humans , Male , Prospective Studies , Workforce
17.
Clin Genet ; 72(4): 288-95, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17850623

ABSTRACT

Mitral valve prolapse (MVP) is a very common clinical condition that refers to a systolic billowing of one or both mitral valve leaflets into the left atrium. Improvements of echocardiographic techniques and new insights in mitral valve anatomy and physiology have rendered the diagnosis of this condition more accurate and reliable. MVP can be sporadic or familial, demonstrating autosomal dominant and X-linked inheritance. Three different loci on chromosomes 16, 11 and 13 have been found to be linked to MVP, but no specific gene has been described. Another locus on chromosome X was found to cosegregate with a rare form of MVP called 'X-linked myxomatous valvular dystrophy'. MVP is more frequent in patients with connective tissue disorders including Marfan syndrome, Ehlers-Danlos and osteogenesis imperfecta. The purpose of this review is to describe previous studies on the genetics and prevalence of MVP. The report warrants the need for further genetically based studies on this common, albeit not fully understood, clinical entity.


Subject(s)
Genetic Predisposition to Disease , Mitral Valve Prolapse/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Chromosomes, Human, X/genetics , Echocardiography/methods , Female , Humans , Male , Middle Aged , Mitral Valve Prolapse/diagnosis , Mitral Valve Prolapse/epidemiology , Reproducibility of Results
18.
Bone Marrow Transplant ; 40(6): 529-33, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17637688

ABSTRACT

Pulmonary infection, often insidious, is frequent in primary immunodeficiency (PID) and acquired immunodeficiency. Pulmonary complications are serious obstacles to success of haematopoietic SCT (HSCT) for these conditions. Bronchoalveolar lavage (BAL) permits identification of lower respiratory tract pathogens that may direct specific treatment and influence prognosis. There are no reports about the utility of pre-HSCT BAL for immunodeficient patients. We prospectively studied the value of 'routine' BAL before commencing transplantation in patients undergoing HSCT for severe immunological disease. Routine non-bronchoscopic BAL was performed under general anaesthetic, a few days before commencing pre-HSCT cytoreductive chemotherapy. Patients were categorized as symptomatic or asymptomatic with respect to pulmonary disease or infection. Samples were sent for microbiological processing. Complications arising from the procedure, pathogens isolated and treatments instituted were recorded. Results were available from 69/75 patients transplanted during the study period; 26 (38%) had pathogens identified (six asymptomatic patients), 10 (14.5%) developed complications post-procedure (two asymptomatic patients)-all recovered, 21 had management changes. There was no statistically significant difference in the number of positive isolates from severe combined or other immunodeficient patients, or of symptomatic or asymptomatic patients. Routine non-bronchoscopic BAL is safe in immunodeficient patients about to undergo HSCT, and leads to management changes.


Subject(s)
Autoimmune Diseases/therapy , Bronchoalveolar Lavage , Hematopoietic Stem Cell Transplantation , Pneumocystis carinii/isolation & purification , Pneumonia, Pneumocystis/diagnosis , Severe Combined Immunodeficiency/therapy , Adolescent , Anesthesia, General , Autoimmune Diseases/complications , Bronchoalveolar Lavage Fluid/microbiology , Child , Child, Preschool , Humans , Infant , Infant, Newborn , Pneumonia, Bacterial/complications , Pneumonia, Bacterial/diagnosis , Pneumonia, Bacterial/immunology , Pneumonia, Pneumocystis/complications , Pneumonia, Pneumocystis/immunology , Prognosis , Prospective Studies , Severe Combined Immunodeficiency/complications
19.
J Clin Pathol ; 59(2): 113-20, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16443724

ABSTRACT

This second best practice review examines five series of common primary care questions in laboratory medicine: (1) laboratory testing for allergy, (2) diagnosis and monitoring of menopause, (3) the use of urine cytology, (4) the usefulness of the erythrocyte sedimentation rate, and (5) the investigation of possible urinary tract infection. The review is presented in a question-answer format. The recommendations represent a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents, and evidence based medicine reviews, supplemented by MEDLINE EMBASE searches to identify relevant primary research documents. They are standards but form a guide to be set in the clinical context. Most are consensus rather than evidence based. They will be updated periodically to take account of new information.


Subject(s)
Pathology, Clinical/methods , Primary Health Care/methods , Blood Sedimentation , Evidence-Based Medicine , Female , Humans , Hypersensitivity/diagnosis , Menopause , Patient Selection , Urinalysis , Urinary Tract Infections/diagnosis
20.
J Clin Pathol ; 58(12): 1339-41, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16311362

ABSTRACT

A previously healthy 11 year old boy died unexpectedly after a rapid course of progressive pneumonia. Postmortem microbiology and histopathology suggested an underlying diagnosis of chronic granulomatous disease. This was confirmed by neutrophil oxidative burst and gene mutation analysis of other family members, one of whom benefited from early bone marrow transplantation.


Subject(s)
Granulomatous Disease, Chronic/diagnosis , Burkholderia Infections/complications , Burkholderia cepacia , Child , Child, Preschool , Chronic Disease , Fatal Outcome , Granulomatous Disease, Chronic/complications , Granulomatous Disease, Chronic/genetics , Humans , Male , Opportunistic Infections/complications , Pneumonia, Bacterial/complications
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