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1.
J Acoust Soc Am ; 154(5): 2828-2842, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37930177

ABSTRACT

Anthropogenic noise is globally increasing in aquatic ecosystems, and there is concern that it may have adverse consequences in many fish species, yet the effects of noise in field settings are not well understood. Concern over the applicability of laboratory-conducted bioacoustic experiments has led to a call for, and a recent increase in, field-based studies, but the results have been mixed, perhaps due to the wide variety of techniques used and species studied. Previous reviews have explored the behavioral, physiological, and/or anatomical costs of fish exposed to anthropogenic noise, but few, if any, have focused on the field techniques and sound sources themselves. This review, therefore, aims to summarize, quantify, and interpret field-based literature, highlight novel approaches, and provide recommendations for future research into the effects of noise on fish.


Subject(s)
Ecosystem , Noise , Animals , Noise/adverse effects , Sound , Fishes/physiology , Behavior, Animal/physiology
2.
Nat Commun ; 13(1): 6641, 2022 11 04.
Article in English | MEDLINE | ID: mdl-36333299

ABSTRACT

Determining the mechanisms by which genes are switched on and off during development is a key aim of current biomedical research. Gene transcription has been widely observed to occur in a discontinuous fashion, with short bursts of activity interspersed with periods of inactivity. It is currently not known if or how this dynamic behaviour changes as mammalian cells differentiate. To investigate this, using an on-microscope analysis, we monitored mouse α-globin transcription in live cells throughout erythropoiesis. We find that changes in the overall levels of α-globin transcription are most closely associated with changes in the fraction of time a gene spends in the active transcriptional state. We identify differences in the patterns of transcriptional bursting throughout differentiation, with maximal transcriptional activity occurring in the mid-phase of differentiation. Early in differentiation, we observe increased fluctuation in transcriptional activity whereas at the peak of gene expression, in early erythroblasts, transcription is relatively stable. Later during differentiation as α-globin expression declines, we again observe more variability in transcription within individual cells. We propose that the observed changes in transcriptional behaviour may reflect changes in the stability of active transcriptional compartments as gene expression is regulated during differentiation.


Subject(s)
Erythroblasts , Erythropoiesis , Mice , Animals , Erythroblasts/metabolism , Cell Differentiation/genetics , Erythropoiesis/genetics , Chromatin/metabolism , alpha-Globins/genetics , alpha-Globins/metabolism , Transcription, Genetic , Globins/genetics , Mammals/genetics
3.
Blood ; 135(22): 1921-1922, 2020 05 28.
Article in English | MEDLINE | ID: mdl-32463887
4.
West Indian Med J ; 65(1): 18-26, 2015 Sep 22.
Article in English | MEDLINE | ID: mdl-26901597

ABSTRACT

OBJECTIVES: To review the history of newborn screening for sickle cell disease with especial reference to Jamaica. METHODS: A summary was done of the history, the development of associated laboratory technology and the implementation of newborn screening for sickle cell disease in Jamaica. RESULTS: Screening was initiated at Victoria Jubilee Hospital, Kingston from 1973-1981, reactivated in 1995 and extended to the University Hospital of the West Indies in 1997 and to Spanish Town Hospital in 1998. From August 2008, there was a progressive recruitment of 12 hospitals in the south and west of Jamaica which has raised the frequency of islandwide newborn coverage from 25% in 1973 to 81%. The results of this extended programme in southwest Jamaica are presented. Dried blood spots collected from the umbilical cord proved stable, cheap and efficient; mean sample collection rates were 98%, maternal contamination occurred in < 1% and caused diagnostic confusion in < 0.1%. By March 31, 2015, a total of 54 566 births have been screened, detecting 161 with homozygous sickle cell (SS) disease, 125 with sickle cell-haemoglobin C (SC) disease and 36 with sickle cell-beta thalassaemia. Of the 327 babies with clinically significant sickle cell syndromes, all except five who died within seven days of birth were confirmed by four to six weeks and recruited to local sickle cell clinics. CONCLUSION: Early detection of sickle cell disease and recruitment to clinics is known to reduce its morbidity and mortality. The methods currently detailed provide an effective and economic model of newborn screening which may be of value elsewhere.

6.
Bone Joint J ; 96-B(7): 936-42, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24986948

ABSTRACT

Inherent disadvantages of reverse shoulder arthroplasty designs based on the Grammont concept have raised a renewed interest in less-medialised designs and techniques. The aim of this study was to evaluate the outcome of reverse shoulder arthroplasty (RSA) with the fully-constrained, less-medialised, Bayley-Walker prosthesis performed for the treatment of rotator-cuff-deficient shoulders with glenohumeral arthritis. A total of 97 arthroplasties in 92 patients (53 women and 44 men, mean age 67 years (standard deviation (sd) 10, (49 to 85)) were retrospectively reviewed at a mean follow-up of 50 months ((sd 25) (24 to 96)). The mean Oxford shoulder score and subjective shoulder value improved from 47 (sd 9) and 24 points (sd 18) respectively before surgery to 28 (sd 11) and 61 (sd 24) points after surgery (p < 0.001). The mean pain at rest decreased from 5.3 (sd 2.8) to 1.5 (sd 2.3) (p < 0.001). The mean active forward elevation and external rotation increased from 42(°)(sd 30) and 9(°) (sd 15) respectively pre-operatively to 78(°) (sd 39) and 24(°) (sd 17) post-operatively (p < 0.001). A total of 20 patients required further surgery for complications; 13 required revision of components. No patient developed scapular notching. The Bayley-Walker prosthesis provides reliable pain relief and reasonable functional improvement for patients with symptomatic cuff-deficient shoulders. Compared with other designs of RSA, it offers a modest improvement in forward elevation, but restores external rotation to some extent and prevents scapular notching. A longer follow-up is required to assess the survival of the prosthesis and the clinical performance over time.


Subject(s)
Arthroplasty, Replacement/methods , Joint Prosthesis , Prosthesis Design , Shoulder Joint/surgery , Aged , Aged, 80 and over , Arthritis/surgery , Female , Humans , Male , Middle Aged , Pain Measurement , Prosthesis Failure , Radiography , Recovery of Function , Rotator Cuff/physiopathology , Shoulder Joint/diagnostic imaging , Shoulder Joint/physiopathology
7.
Pak J Biol Sci ; 17(7): 898-904, 2014 Jul.
Article in English | MEDLINE | ID: mdl-26035938

ABSTRACT

This third year work was carried on at Khon Kaen University during the 2008-2009 to investigate dry matter yields of grass, grass plus legumes, grown on Korat soil series (Oxic Paleustults). The experiment consisted of twelve-treatment combinations of a 3x4 factorial arranged in a Randomized Complete Block Design (RCBD) with four replications. The results showed that Dry Matter Yields (DMY) of Ruzi and Guinea grass were similar with mean values of 6,585 and 6,130 kg ha(-1) whilst Napier gave the lowest (884 kg ha(-1)). With grass plus legume, grass species and production methods gave highly significant dry matter yields where Guinea and Ruzi gave dry matter yields of 7,165 and 7,181 kg ha(-1), respectively and Napier was the least (2,790 kg ha(-1)). The production methods with the use of cattle manure gave the highest DMY (grass alone) of 10,267 kg ha(-1) followed by Wynn and Verano with values of 6,064 and 3,623 kg ha(-1), respectively. Guinea plus cattle manure gave the highest DMY of 14,599 kg ha(-1) whilst Ruzi gave 12,977 kg ha(-1). Guinea plus Wynn gave DMY of 7,082 kg ha(-1). Ruzi plus Verano gave DMY of 6,501 kg ha(-1). Forage qualities of crude protein were highest with those grown with grass plus legumes. Some prospects in improving production were discussed.


Subject(s)
Animal Feed , Poaceae , Climate , Thailand
8.
J Phys Chem A ; 117(46): 12026-34, 2013 Nov 21.
Article in English | MEDLINE | ID: mdl-23898915

ABSTRACT

The electrical Ca test was used to measure H2O vapor transmission through polyethylene naphthalate (PEN) polymer with a thickness of 200 µm. On the basis of the time required for the normalized conductance of the Ca film to reach zero, the H2O vapor transmission rate was determined versus H2O flux, temperature, and saturation of the PEN polymer with H2O. The H2O vapor transmission rate was proportional to the H2O flux and only weakly dependent on temperature at constant H2O flux. The transmission coefficient, Γ, for H2O through the PEN polymer at 70 °C was Γ âˆ¼ 3.2 × 10(-10). The corresponding water vapor transmission rate (WVTR) at 70 °C/80% RH was 0.65 g/(m(2) day). The temperature dependence of the H2O vapor transmission rate through PEN at constant H2O flux yielded an activation barrier of E = 12.4 kJ/mol. There was no observable reservoir effect for H2O in the PEN polymer. The H2O vapor transmission rates for initially dry or H2O-saturated PEN polymer substrates were nearly identical at various temperatures. Although the time required for the normalized conductance of the Ca film to reach zero was inversely proportional to the H2O flux, the Ca film conductance did not decrease linearly versus H2O exposure. The Ca film conductance changed very little during initial H2O exposure. This behavior may be caused by the nonlinear oxidation kinetics of the Ca film.

9.
Biol Lett ; 9(4): 20130163, 2013 Aug 23.
Article in English | MEDLINE | ID: mdl-23697639

ABSTRACT

The New Zealand bigeye, Pempheris adspersa, is a nocturnal planktivore and has recently been found to be an active sound producer. The rostral end of the swim bladder lies adjacent to Baudelot's ligament which spans between the bulla and the cleithrum bone of the pectoral girdle. The aim of this study was to use the auditory evoked potential technique to physiologically test the possibility that this structure provides an enhanced sensitivity to sound pressure in the bigeye. At 100 Hz, bigeye had hearing sensitivity similar to that of goldfish (species with a mechanical connection between the swim bladder and the inner ear mediated by the Weberian ossicles) and were much more sensitive than other teleosts without ancillary hearing structures. Severing Baudelot's ligament bilaterally resulted in a marked decrease in hearing sensitivity, as did swim bladder puncture or lateral line blockage. These results show that bigeye have an enhanced sensitivity to sound pressure and provide experimental evidence that the functional basis of this sensitivity represents a novel hearing specialization in fish involving the swim bladder, Baudelot's ligament and the lateral line.


Subject(s)
Air Sacs/physiology , Auditory Perception , Evoked Potentials, Auditory , Hearing , Perciformes/physiology , Air Sacs/anatomy & histology , Air Sacs/diagnostic imaging , Animals , Magnetic Resonance Imaging , New Zealand , Perciformes/anatomy & histology , Pressure , Sound , X-Ray Microtomography
10.
J Exp Biol ; 216(Pt 8): 1484-90, 2013 Apr 15.
Article in English | MEDLINE | ID: mdl-23264489

ABSTRACT

In the underwater environment, sound propagates both as a pressure wave and as particle displacement, with particle displacement dominating close to the source (the nearfield). At the receptor level, both the fish ear and the neuromast hair cells act as displacement detectors and both are potentially stimulated by the particle motion component of sound sources, especially in the nearfield. A now common way to test 'hearing' in fish involves auditory evoked potentials (AEPs), with recordings made from electrodes implanted near the auditory brainstem. These AEP recordings are typically conducted in enclosed acoustic environments with the fish well within the nearfield, especially for lower frequencies. We tested the contribution of neuromast hair cells to AEP by first testing intact goldfish (Carassius auratus), then ablating their neuromasts with streptomycin sulphate--disabling superficial and canal neuromasts--and retesting the same goldfish. We performed a similar experiment where only the superficial neuromasts were physically ablated. At 100 and 200 Hz, there was a 10-15 dB increase in threshold after streptomycin treatment but no significant difference at higher frequencies. There was no difference in threshold in control fish or in fish that only had superficial neuromasts removed, indicating that the differential responses were driven by canal neuromasts. Taken together, these results indicate that AEP results at lower frequencies should be interpreted as multimodal responses, rather than as 'hearing'. The results also suggest that in natural situations both the ear and lateral line likely play an integrative role in detecting and localising many types of 'acoustic' stimuli.


Subject(s)
Evoked Potentials, Auditory , Goldfish/physiology , Hair Cells, Auditory/physiology , Acoustic Stimulation , Animals , Auditory Threshold/drug effects , Evoked Potentials, Auditory/drug effects , Hair Cells, Auditory/drug effects , Hearing , Protein Synthesis Inhibitors/metabolism , Streptomycin/metabolism
11.
West Indian med. j ; 61(7): 684-691, Oct. 2012. tab
Article in English | LILACS | ID: lil-672985

ABSTRACT

OBJECTIVE: To compare the haematological and clinical features of homozygous sickle cell (SS) disease in Bantu and Benin haplotypes in a cross-sectional study of 115 Ugandan patients attending the Sickle Cell Clinic at Mulago Hospital, Kampala, Uganda, with 311 patients in the Jamaican Cohort Study. METHODS: This involved comparison of clinical features and haematology with special reference to genetic determinants of severity including fetal haemoglobin levels, beta-globin haplotype and alpha thalassaemia status. RESULTS: The Bantu haplotype accounted for 94% of HbS chromosomes in Ugandan patients and the Benin haplotype for 76% of HbS chromosomes in Jamaica. Ugandan patients were marginally more likely to have alpha thalassaemia, had similar total haemoglobin and fetal haemoglobin levels but had higher reticulocyte counts and total bilirubin levels consistent with greater haemolysis. Ugandan patients had less leg ulceration and priapism, but the mode of clinical presentation, prevalence of dactylitis, features of bone pain and degree of delay in sexual development, assessed by menarche, were similar in the groups. In Ugandan patients, a history of anaemic episodes was common but these were poorly documented. CONCLUSION: The haematological and clinical features of the Bantu haplotype in Uganda were broadly similar to the Benin haplotype in Jamaica except for less leg ulceration and priapism and possibly greater haemolysis among Ugandan subjects. Anaemic episodes in Uganda were treated empirically by transfusion often without a clear diagnosis; better documentation including reticulocyte counts and observations on spleen size is necessary to evolve appropriate models of care.


OBJETIVO: Comparar los rasgos clínicos de la anemia de células falciformes homocigóticas (SS) en los haplotipos Bantú y Benin en un estudio transversal de 115 pacientes ugandeses que asisten a la Clínica de la anemia de células falciformes en el Hospital de Mulago, Kampala, Uganda, con 311 pacientes en un estudio de cohorte jamaicano. MÉTODOS: El estudio conllevó la comparación de los rasgos clínicos y hematológicos con referencia especial a los determinantes genéticos de la severidad, incluyendo los niveles de la hemoglobina fetal, haplotipos del gen de la globina beta, y el estado de la alfa talasemia. RESULTADOS: El haplotipo Bantú dio cuenta del 94% de los cromosomas HbS en los pacientes ugandeses, en tanto que los haplotipos Benin dieron cuenta del 76% de los cromosomas de HbS en Jamaica. Los pacientes de Uganda presentaron una probabilidad marginalmente mayor de alfa talasemia, tenían niveles similares de hemoglobina total y hemoglobina fetal, pero en cambio presentaban conteos más altos de reticulocitos así como niveles mayores de bilirrubina total, en correspondencia con una mayor hemólisis. Los pacientes ugandeses presentaban menor ulceración de las piernas y priapismo, pero el modo de presentación clínica, la prevalencia de dactilitis, los rasgos de dolor óseo, y el grado de retraso en el desarrollo sexual, evaluado por la menarquia, fueron similares en todos los grupos. Los pacientes de Uganda se caracterizaron comúnmente por una historia de episodios de anemia, pobremente documentados. CONCLUSIÓN: Los rasgos clínicos y hematológicos del haplotipo Bantú en Uganda fueron considerablemente similares al haplotipo Benin en Jamaica, salvo por una menor presencia de ulceración de las piernas y priapismo, así como posiblemente mayor hemólisis entre los sujetos de Uganda. Los episodios de anemia en Uganda fueron tratados empíricamente mediante transfusión, a menudo sin un diagnóstico claro. Se necesita una mejor documentación - incluyendo conteos de reticulocitos - así como observaciones del tamaño del bazo, a fin de desarrollar modelos de cuidado apropiados.


Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Young Adult , Anemia, Sickle Cell/genetics , Hemoglobin, Sickle/genetics , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/physiopathology , Bilirubin/blood , Cohort Studies , Cross-Sectional Studies , Fetal Hemoglobin/analysis , Haplotypes , Hemoglobin, Sickle/classification , Homozygote , Jamaica , Musculoskeletal Pain/etiology , Priapism/etiology , Puberty, Delayed/etiology , Reticulocytes/cytology , Skin Ulcer/etiology , Splenomegaly/diagnosis , Splenomegaly/epidemiology , Uganda , alpha-Thalassemia/complications , beta-Globins/classification , beta-Globins/genetics
12.
J Bone Joint Surg Br ; 94(10): 1382-9, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23015565

ABSTRACT

There is little information about the management of peri-prosthetic fracture of the humerus after total shoulder replacement (TSR). This is a retrospective review of 22 patients who underwent a revision of their original shoulder replacement for peri-prosthetic fracture of the humerus with bone loss and/or loose components. There were 20 women and two men with a mean age of 75 years (61 to 90) and a mean follow-up 42 months (12 to 91): 16 of these had undergone a previous revision TSR. Of the 22 patients, 12 were treated with a long-stemmed humeral component that bypassed the fracture. All their fractures united after a mean of 27 weeks (13 to 94). Eight patients underwent resection of the proximal humerus with endoprosthetic replacement to the level of the fracture. Two patients were managed with a clam-shell prosthesis that retained the original components. The mean Oxford shoulder score (OSS) of the original TSRs before peri-prosthetic fracture was 33 (14 to 48). The mean OSS after revision for fracture was 25 (9 to 31). Kaplan-Meier survival using re-intervention for any reason as the endpoint was 91% (95% confidence interval (CI) 68 to 98) and 60% (95% CI 30 to 80) at one and five years, respectively. There were two revisions for dislocation of the humeral head, one open reduction for modular humeral component dissociation, one internal fixation for nonunion, one trimming of a prominent screw and one re-cementation for aseptic loosening complicated by infection, ultimately requiring excision arthroplasty. Two patients sustained nerve palsies. Revision TSR after a peri-prosthetic humeral fracture associated with bone loss and/or loose components is a salvage procedure that can provide a stable platform for elbow and hand function. Good rates of union can be achieved using a stem that bypasses the fracture. There is a high rate of complications and function is not as good as with the original replacement.


Subject(s)
Arthroplasty, Replacement/adverse effects , Humeral Fractures/surgery , Shoulder Joint/surgery , Aged , Aged, 80 and over , Bone Resorption/etiology , Female , Humans , Humeral Fractures/etiology , Male , Middle Aged , Prosthesis Failure , Reoperation , Retrospective Studies
13.
J Bone Joint Surg Br ; 94(9): 1253-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22933499

ABSTRACT

Scapulothoracic fusion (STF) for painful winging of the scapula in neuromuscular disorders can provide effective pain relief and functional improvement, but there is little information comparing outcomes between patients with dystrophic and non-dystrophic conditions. We performed a retrospective review of 42 STFs in 34 patients with dystrophic and non-dystrophic conditions using a multifilament trans-scapular, subcostal cable technique supported by a dorsal one-third semi-tubular plate. There were 16 males and 18 females with a mean age of 30 years (15 to 75) and a mean follow-up of 5.0 years (2.0 to 10.6). The mean Oxford shoulder score improved from 20 (4 to 39) to 31 (4 to 48). Patients with non-dystrophic conditions had lower overall functional scores but achieved greater improvements following STF. The mean active forward elevation increased from 59° (20° to 90°) to 97° (30° to 150°), and abduction from 51° (10° to 90°) to 83° (30° to 130°) with a greater range of movement achieved in the dystrophic group. Revision fusion for nonunion was undertaken in five patients at a mean time of 17 months (7 to 31) and two required revision for fracture. There were three pneumothoraces, two rib fractures, three pleural effusions and six nonunions. The main risk factors for nonunion were smoking, age and previous shoulder girdle surgery. STF is a salvage procedure that can provide good patient satisfaction in 82% of patients with both dystrophic and non-dystrophic pathologies, but there was a relatively high failure rate (26%) when poor outcomes were analysed. Overall function was better in patients with dystrophic conditions which correlated with better range of movement; however, patients with non-dystrophic conditions achieved greater functional improvement.


Subject(s)
Neuromuscular Diseases/complications , Scapula/abnormalities , Scapula/surgery , Shoulder Joint/surgery , Spinal Diseases/surgery , Spinal Fusion/methods , Thoracic Vertebrae/surgery , Activities of Daily Living , Adolescent , Adult , Aged , Female , Follow-Up Studies , Fractures, Ununited/etiology , Gait , Humans , Male , Middle Aged , Pain, Postoperative/epidemiology , Pain, Postoperative/prevention & control , Patient Satisfaction , Postoperative Complications/etiology , Posture , Range of Motion, Articular , Reoperation , Retrospective Studies , Risk Factors , Salvage Therapy , Shoulder Joint/physiopathology , Spinal Diseases/etiology , Spinal Fusion/adverse effects , Spine/physiopathology , Treatment Outcome , Young Adult
14.
West Indian Med J ; 61(7): 684-91, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23620965

ABSTRACT

OBJECTIVE: To compare the haematological and clinical features of homozygous sickle cell (SS) disease in Bantu and Benin haplotypes in a cross-sectional study of 115 Ugandan patients attending the Sickle Cell Clinic at Mulago Hospital, Kampala, Uganda, with 311 patients in the Jamaican Cohort Study METHODS: This involved comparison of clinical features and haematology with special reference to genetic determinants of severity including fetal haemoglobin levels, beta-globin haplotype and alpha thalassaemia status. RESULTS: The Bantu haplotype accounted for 94% of HbS chromosomes in Ugandan patients and the Benin haplotype for 76% of HbS chromosomes in Jamaica. Ugandan patients were marginally more likely to have alpha thalassaemia, had similar total haemoglobin and fetal haemoglobin levels but had higher reticulocyte counts and total bilirubin levels consistent with greater haemolysis. Ugandan patients had less leg ulceration and priapism, but the mode of clinical presentation, prevalence of dactylitis, features of bone pain and degree of delay in sexual development, assessed by menarche, were similar in the groups. In Ugandan patients, a history of anaemic episodes was common but these were poorly documented. CONCLUSION: The haematological and clinical features of the Bantu haplotype in Uganda were broadly similar to the Benin haplotype in Jamaica except for less leg ulceration and priapism and possibly greater haemolysis among Ugandan subjects. Anaemic episodes in Uganda were treated empirically by transfusion often without a clear diagnosis; better documentation including reticulocyte counts and observations on spleen size is necessary to evolve appropriate models of care.


Subject(s)
Anemia, Sickle Cell/genetics , Hemoglobin, Sickle/genetics , Adolescent , Adult , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/physiopathology , Bilirubin/blood , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Female , Fetal Hemoglobin/analysis , Haplotypes , Hemoglobin, Sickle/classification , Homozygote , Humans , Infant , Jamaica , Male , Middle Aged , Musculoskeletal Pain/etiology , Priapism/etiology , Puberty, Delayed/etiology , Reticulocytes/cytology , Skin Ulcer/etiology , Splenomegaly/diagnosis , Splenomegaly/epidemiology , Uganda , Young Adult , alpha-Thalassemia/complications , beta-Globins/classification , beta-Globins/genetics
15.
J Fish Biol ; 77(7): 1488-504, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21078014

ABSTRACT

The auditory abilities of the round goby Neogobius melanostomus were quantified using auditory evoked potential recordings, using tone bursts and conspecific call stimuli. Fish were tested over a range of sizes to assess effects of growth on hearing ability. Tests were also run with and without background noise to assess the potential effects of masking in a natural setting. Neogobius melanostomus detected tone bursts from 100 to 600 Hz with no clear best frequency in the pressure domain but were most sensitive to 100 Hz tone stimuli when examined in terms of particle acceleration. Responses to a portion of the N. melanostomus call occurred at a significantly lower threshold than responses to pure tone stimulation. There was no effect of size on N. melanostomus hearing ability, perhaps due to growth of the otolith keeping pace with growth of the auditory epithelium. Neogobius melanostomus were masked by both ambient noise and white noise, but not until sound pressure levels were relatively high, having a 5-10 dB threshold shift at noise levels of 150 dB re 1 µPa and higher but not at lower noise levels.


Subject(s)
Acoustic Stimulation/veterinary , Auditory Perception/physiology , Evoked Potentials, Auditory/physiology , Noise , Perciformes/physiology , Animals , Auditory Threshold/physiology , Body Size
16.
Comp Biochem Physiol B Biochem Mol Biol ; 154(1): 121-33, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19470409

ABSTRACT

Growth hormone (GH) transgenesis results in increased growth, feed intake and consequent metabolic rates in fish, and alters the utilization of dietary and stored carbohydrates, lipid and protein. However, the manner in which GH transgenesis differentially alters these energy sources in fish has not been well explored. We examined the effects of GH transgenesis and dietary carbohydrate, lipid and protein levels on metabolic enzyme activity in coho salmon (Oncorhynchus kisutch). In white muscle, increased activities of glycolytic enzymes and decreased activities of lipolytic enzymes in transgenic fish indicate a sparing of lipids through the preferential use of carbohydrates for energy production. In liver, transgenic fish showed increased activity of lipid synthesis enzymes and a shift in amino acid metabolism from catabolic to synthetic roles, suggesting a larger emphasis on anabolic pathways in transgenic fish to support accelerated growth. Unlike nontransgenic fish, transgenic fish fed a diet high in carbohydrates maintained growth rates, had increased capacity for lipid synthesis, and increased potential for biosynthetic roles of amino acids. GH transgenesis influences metabolic reactions in coho salmon by emphasizing carbohydrate degradation for energy production and lipid synthesis, and increasing utilization of lipids and proteins for synthetic roles necessary to maintain accelerated growth.


Subject(s)
Carbohydrate Metabolism/genetics , Energy Metabolism/genetics , Fish Proteins/metabolism , Growth Hormone/genetics , Growth Hormone/metabolism , Lipid Metabolism/genetics , Oncorhynchus kisutch/genetics , Oncorhynchus kisutch/metabolism , Animal Feed , Animals , Animals, Genetically Modified , Carbohydrate Metabolism/drug effects , Carbohydrates/biosynthesis , Dietary Carbohydrates/pharmacology , Dietary Proteins/pharmacology , Gene Transfer Techniques , Intestines/enzymology , Lipid Metabolism/drug effects , Lipids/biosynthesis , Liver/enzymology , Muscles/enzymology , Transgenes/genetics
17.
Cell Mol Life Sci ; 66(7): 1154-62, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19020805

ABSTRACT

Recent work in the alpha thalassaemia field has started to provide some indication of the mechanisms involved in the very high frequency of the different forms of alpha thalassaemia among the populations of tropical countries, and, at the same time, is starting to define at least some of the mechanisms for its remarkable phenotypic heterogeneity. These diseases continue to provide extremely valuable models for the better understanding of the regulation of the alpha globin genes, and for human molecular pathology in general. The much less common disorders, ATR-16 and ATR-X are also providing valuable information about the spectrum of molecular lesions associated with different forms of mental retardation and about the molecular mechanisms involved in their varying phenotypes.


Subject(s)
alpha-Thalassemia/genetics , Genetic Variation , Genetics, Population , Genotype , Hemoglobins/genetics , Humans , Mental Retardation, X-Linked/genetics , Neural Tube Defects/genetics , Phenotype , Tropical Medicine , alpha-Globins/genetics , alpha-Thalassemia/epidemiology
18.
Int J Lab Hematol ; 31(6): 585-96, 2009 Dec.
Article in English | MEDLINE | ID: mdl-18644042

ABSTRACT

Earlier reports on homozygous sickle cell (SS) disease have been biased by severely affected cases. The Jamaican clinic which seeks to avoid such bias has 102 patients surviving beyond 60 years. The objective of this study was to examine the features of elderly cases and assess factors determining survival and the behaviour of this disease with advancing age. A retrospective review of all cases and prospective assessment in survivors was conducted at The Sickle Cell Clinic at the University of the West Indies, Kingston, Jamaica previously operated by the MRC Laboratories. All patients with SS disease born prior to December 31, 1943 who would, by January 2004, have passed their 60th birthday were traced and their current status ascertained. The molecular and clinical features were assessed and observations on the clinical behaviour of the disease and of haematology and biochemistry are presented. Of the 102 patients, 58 had died, four had emigrated and 40 were alive, resident in Jamaica and aged 60-87 years. Survival was associated with female gender and higher foetal haemoglobin but not with alpha-thalassaemia or beta-globin haplotype. A tendency to familial clustering among elderly survivors did not reach statistical significance. Painful crises ameliorated with age and there was a benign course in pregnancy. Mean haemoglobin levels fell with age and were generally associated with rising creatinine levels indicating the importance of renal failure. Elderly survivors present some features of intrinsic mildness but also manifest age-related amelioration of painful crises and falling haemoglobin levels from progressive renal damage.


Subject(s)
Anemia, Sickle Cell , Aged , Aged, 80 and over , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/mortality , Female , Fetal Hemoglobin , Homozygote , Humans , Jamaica/epidemiology , Longitudinal Studies , Male , Pregnancy , Pregnancy Complications, Hematologic , Retrospective Studies , beta-Globins/genetics
19.
Environ Sci Technol ; 41(2): 437-43, 2007 Jan 15.
Article in English | MEDLINE | ID: mdl-17310704

ABSTRACT

This study compared the flesh quality of farmed and wild sources of British Columbia (BC) salmon with respect to concentrations of polychlorinated biphenyl compounds, polychlorinated dibenzodioxins/dibenzofurans and their associated toxic equivalents, total mercury (THg), methylmercury (MeHg), and selected fatty acids of known importance for human health viz., omega-3 (n-3) highly unsaturated fatty acids (n-3 HUFAs) and (n-6) fatty acids. Skinned fillets from known sources of farmed Atlantic, coho, and chinook salmon (n = 110) and wild coho, chinook, chum, sockeye, and pink salmon (n = 91) were examined. Atlantic salmon contained higher PCB concentrations (means, 28-38 ng/g) than farmed coho or chinook salmon, and levels in these latter species were similar to those in wild counterparts (means, 2.8-13.7 ng/g). PCB levels in Atlantic salmon flesh were, nevertheless, 53-71-fold less than the level of concern for human consumption of fish, i.e., 2000 ng/g as established by Health Canada and the U.S. Food and Drug Administration (US-FDA). Similarly, THg and MeHg levels in all samples were well below the Health Canada guideline (0.5 microg/g) and the US-FDA action level (1.0 microg/g). On average, THg in farmed salmon (0.021 microg/g) was similar to or lower than wild salmon (0.013-0.077 microg/g). Atlantic salmon were a richer source (mean, 2.34 g/100 g fillet) of n-3 HUFAs than the other farmed and wild sources of salmon examined (means, 0.39-1.17 g/100 g). The present findings support the recommended weekly consumption guidelines for oily fish species (includes all BC salmon sources) for cardio-protective benefits as made by the American Heart Association and the UK Food Standards Agency.


Subject(s)
Benzofurans/analysis , Dioxins/analysis , Environmental Monitoring/statistics & numerical data , Fatty Acids/analysis , Mercury Compounds/analysis , Polychlorinated Biphenyls/analysis , Salmon/metabolism , Water Pollutants, Chemical/analysis , Animals , Aquaculture , British Columbia , Muscle, Skeletal/chemistry
20.
Br J Nurs ; 15(18): 1012-6, 2006.
Article in English | MEDLINE | ID: mdl-17077774

ABSTRACT

Temperature is a vital sign which can be measured using various types of clinical thermometers. Pulmonary artery temperature is considered the 'gold standard', but this measurement is not usually clinically practical. There is currently no consensus for optimal alternative site or equipment. This research compares 178 simultaneous measurements from 5 clinical areas, using two types of thermometers: tympanic and no-touch temporal. No-touch thermometers were all set to oral equivalent. Tympanic thermometers were adjusted to either oral (n=105) or core (n=73) equivalent. Maximum acceptable difference was identified as 1oC. Two data sets (oral/core; oral/oral) were analysed using Bland-Altman method on Excel programmes, comparing all thermometers and separating oral and core-equivalent tympanics. The two thermometers were found not to be equivalent. As a simple comparison between two thermometers, this research cannot identify which thermometer is more accurate.


Subject(s)
Temporal Arteries , Thermography/instrumentation , Thermometers/standards , Tympanic Membrane , Bias , Body Temperature , Calibration , Catheterization, Swan-Ganz , Clinical Nursing Research , Confidence Intervals , Confounding Factors, Epidemiologic , Evidence-Based Medicine , Humans , Mouth , Nursing Assessment , Reference Values , Thermography/standards
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