Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Oecologia ; 199(2): 453-470, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35689680

ABSTRACT

Among ectotherms, rare species are expected to have a narrower thermal niche breadth and reduced acclimation capacity and thus be more vulnerable to global warming than their common relatives. To assess these hypotheses, we experimentally quantified the thermal sensitivity of seven common, uncommon, and rare species of temperate marine annelids of the genus Ophryotrocha to assess their vulnerability to ocean warming. We measured the upper and lower limits of physiological thermal tolerance, survival, and reproductive performance of each species along a temperature gradient (18, 24, and 30 °C). We then combined this information to produce curves of each species' fundamental thermal niche by including trait plasticity. Each thermal curve was then expressed as a habitat suitability index (HSI) and projected for the Mediterranean Sea and temperate Atlantic Ocean under a present day (1970-2000), mid- (2050-2059) and late- (2090-2099) 21st Century scenario for two climate change scenarios (RCP2.6 and RCP8.5). Rare and uncommon species showed a reduced upper thermal tolerance compared to common species, and the niche breadth and acclimation capacity were comparable among groups. The simulations predicted an overall increase in the HSI for all species and identified potential hotspots of HSI decline for uncommon and rare species along the warm boundaries of their potential distribution, though they failed to project the higher sensitivity of these species into a greater vulnerability to ocean warming. In the discussion, we provide some caveats on the implications of our results for conservation efforts.


Subject(s)
Climate Change , Global Warming , Acclimatization , Ecosystem , Oceans and Seas , Temperature
2.
J Fish Biol ; 92(3): 790-803, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29537084

ABSTRACT

This paper aims to highlight the risk of climate change on coupled marine human and natural systems and explore possible solutions to reduce such risk. Specifically, it explores some of the key responses of marine fish stocks and fisheries to climate change and their implications for human society. It highlights the importance of mitigating carbon emission and achieving the Paris Agreement in reducing climate risk on marine fish stocks and fisheries. Finally, it discusses potential opportunities for helping fisheries to reduce climate threats, through local adaptation. A research direction in fish biology and ecology is proposed that would help support the development of these potential solutions.


Subject(s)
Climate Change , Conservation of Natural Resources/methods , Fisheries , Animals , Conservation of Natural Resources/legislation & jurisprudence , Ecosystem , Fishes/physiology , Humans , Oceans and Seas
3.
Science ; 349(6243): aac4722, 2015 Jul 03.
Article in English | MEDLINE | ID: mdl-26138982

ABSTRACT

The ocean moderates anthropogenic climate change at the cost of profound alterations of its physics, chemistry, ecology, and services. Here, we evaluate and compare the risks of impacts on marine and coastal ecosystems­and the goods and services they provide­for growing cumulative carbon emissions under two contrasting emissions scenarios. The current emissions trajectory would rapidly and significantly alter many ecosystems and the associated services on which humans heavily depend. A reduced emissions scenario­consistent with the Copenhagen Accord's goal of a global temperature increase of less than 2°C­is much more favorable to the ocean but still substantially alters important marine ecosystems and associated goods and services. The management options to address ocean impacts narrow as the ocean warms and acidifies. Consequently, any new climate regime that fails to minimize ocean impacts would be incomplete and inadequate.


Subject(s)
Aquatic Organisms , Carbon Dioxide , Ecosystem , Global Warming , Greenhouse Effect , Animals , Aquaculture , Health , Humans , Oceans and Seas , Risk , Travel
4.
Ann Oncol ; 25(7): 1391-1397, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24728036

ABSTRACT

BACKGROUND: Mantle cell lymphoma (MCL) is aggressive, and relapsed/refractory disease has poor outcomes. PATIENTS AND METHODS: Thirty-nine patients (men = 34, women = 5) at 64 (41-82) years of age with relapsed/refractory MCL, ineligible for high-dose chemotherapy and had received 2 (1-5) prior regimens, were treated with a continuous oral regimen, comprising oral arsenic trioxide (oral-As2O3), chlorambucil and ascorbic acid. RESULTS: Overall response rate was 49% (complete response, CR = 28%; partial response, PR = 21%). Only grade 1/2 toxicities were observed (hematologic: 56%, hepatic: 8%). Response was maintained in 11 patients (CR = 8; PR = 3), after a median of 24 (2-108) months. Independent prognostic factors for response were increased lactate dehydrogenase (P = 0.04) and unfavorable MCL international prognostic index (P = 0.04). At a median follow-up of 21 (1-118) months, the median progression-free survival (PFS) was 16 months, and overall survival (OS) 38 months. Independent prognostic factors for PFS were female gender (P = 0.002), and Eastern Cooperative Oncology Group (ECOG) performance score of 2 (P = 0.009). Independent prognostic factors for OS were female gender (P < 0.001), ECOG performance score of 2 (P = 0.03), non-response (P < 0.001), and disease progression after initial response (P = 0.05). CONCLUSION: An oral regimen of oral-As2O3, chlorambucil and ascorbic acid was active with minimal toxicity in relapsed/refractory MCL, achieving durable responses in ∼30% of cases.


Subject(s)
Arsenicals/therapeutic use , Lymphoma, Mantle-Cell/drug therapy , Oxides/therapeutic use , Salvage Therapy , Administration, Oral , Adult , Aged , Aged, 80 and over , Arsenic Trioxide , Arsenicals/administration & dosage , Humans , Lymphoma, Mantle-Cell/diagnostic imaging , Middle Aged , Oxides/administration & dosage , Positron-Emission Tomography , Recurrence , Survival Analysis
5.
Intern Med J ; 43(5): 541-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23279203

ABSTRACT

BACKGROUND: Invasive fungal disease (IFD) is an important problem complicating the therapy of haematologic patients. AIM: This study aimed to provide data on the epidemiology of IFD in an Asian teaching hospital, as well as the prescription practice of antifungal drugs. METHOD: We conducted a retrospective review of 275 haematologic patients who were prescribed antifungal drugs in a 4-year period (2007-2010), of whom 130 (47%) had undergone haematopoietic stem cell transplantation. RESULTS: Antifungal prophylaxis with either fluconazole or itraconazole was given in 214 patients (78%). There were 414 prescriptions of antifungal drugs (including liposomal amphotericin B, voriconazole, caspofungin, micafungin, anidulafungin), of which 361 prescriptions were empirical. There were 14 patients with proven IFD, 11 of whom had breakthrough infection while on itraconazole prophylaxis. Interestingly, seven of these cases were due to infection by itraconazole-sensitive candida. CONCLUSION: These results provide important epidemiologic data necessary for the formulation of strategies for prevention and treatment of IFD in Asian patients.


Subject(s)
Antifungal Agents/therapeutic use , Hematologic Diseases/drug therapy , Hematologic Diseases/epidemiology , Hospitals, Teaching/trends , Mycoses/drug therapy , Mycoses/epidemiology , Adult , Aged , Aged, 80 and over , Asia/epidemiology , Female , Hospitals, Teaching/methods , Hospitals, University/trends , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
6.
Philos Trans R Soc Lond B Biol Sci ; 367(1596): 1746-56, 2012 Jun 19.
Article in English | MEDLINE | ID: mdl-22566680

ABSTRACT

Physiological studies focus on the responses of cells, tissues and individuals to stressors, usually in laboratory situations. Conservation and management, on the other hand, focus on populations. The field of conservation physiology addresses the question of how abiotic drivers of physiological responses at the level of the individual alter requirements for successful conservation and management of populations. To achieve this, impacts of physiological effects at the individual level need to be scaled to impacts on population dynamics, which requires consideration of ecology. Successfully realizing the potential of conservation physiology requires interdisciplinary studies incorporating physiology and ecology, and requires that a constructive dialogue develops between these traditionally disparate fields. To encourage this dialogue, we consider the increasingly explicit incorporation of physiology into ecological models applied to marine fish conservation and management. Conservation physiology is further challenged as the physiology of an individual revealed under laboratory conditions is unlikely to reflect realized responses to the complex variable stressors to which it is exposed in the wild. Telemetry technology offers the capability to record an animal's behaviour while simultaneously recording environmental variables to which it is exposed. We consider how the emerging insights from telemetry can strengthen the incorporation of physiology into ecology.


Subject(s)
Behavior, Animal , Conservation of Natural Resources/methods , Fishes/physiology , Telemetry/methods , Adaptation, Physiological , Animals , Climate Change , Ecosystem , Fishes/metabolism , Marine Biology/methods , Models, Biological , Oxygen/metabolism , Population Dynamics , Temperature
7.
Hong Kong Med J ; 17(4): 261-6, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21813892

ABSTRACT

OBJECTIVE: To provide a synopsis of current thalassaemia major patient care in Hong Kong. DESIGN: Retrospective study. SETTING: All haematology units of the Hospital Authority in Hong Kong. PATIENTS: All patients with thalassaemia major with regular transfusion. RESULTS: To date, there were 363 thalassaemia major patients under the care of the Hospital Authority. Prenatal diagnosis has helped to reduce the number of indigenous new cases, but in recent years immigrant cases are appearing. The patients have a mean age of 23 (range, 1-52) years, and 78% of them are adults. In 2009, they received 18 782 units of blood. This accounted for 9.5% of all blood consumption from the Hong Kong Red Cross. In the past, cardiac iron overload was the major cause of death (65%) and few patients survived beyond the age of 45 years. The availability of cardiac iron assessment by magnetic resonance imaging (T2 MRI) to direct the use of oral deferiprone chelation has reduced the prevalence of heart failure and cardiac haemosiderosis, which should reduce mortality and improve life expectancy. CONCLUSION: The future for thalassaemia care in Hong Kong is bright. With better transfusion and chelation, it should be possible to avoid growth and endocrine deficiencies in younger patients.


Subject(s)
Thalassemia/therapy , Adolescent , Adult , Child , Child, Preschool , Erythrocyte Transfusion , Hong Kong , Humans , Infant , Iron Overload/etiology , Middle Aged , Osteoporosis/etiology , Retrospective Studies , Thalassemia/complications , Thalassemia/mortality
9.
Gut ; 54(11): 1597-603, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16000641

ABSTRACT

BACKGROUND: The hepatic outcome of hepatitis B surface antigen (HBsAg) positive patients undergoing chemotherapy after withdrawal of pre-emptive lamivudine is unknown. AIMS: To examine the occurrence of hepatitis B virus (HBV) reactivation after withdrawal of pre-emptive lamivudine. METHODS: Pre-emptive lamivudine was started one week before initiation of chemotherapy in 46 consecutive HBsAg positive patients and continued for the entire duration of chemotherapy. Pre-emptive lamivudine was stopped at a median 3.1 (range 3.0-3.4) months after completion of chemotherapy. Patients were longitudinally followed up after withdrawal of pre-emptive lamivudine. RESULTS: Median time of follow up after withdrawal of lamivudine was 25.7 (range 5.7-75.7) months. Eleven of the 46 patients (23.9%) developed HBV reactivation after withdrawal of pre-emptive lamivudine. Eight of the 16 patients with high pre-chemotherapy HBV DNA (> or =10(4) copies/ml) compared with three of the 30 patients with low pre-chemotherapy HBV DNA (<10(4) copies/ml) developed HBV reactivation (50.0% v 10.0%, respectively; p<0.001). Hepatitis B e antigen positive patients were also more likely to develop HBV reactivation (5/11 (45.5%) v 6/35 (17.1%), respectively; p = 0.041). A high pre-chemotherapy HBV DNA (> or =10(4) copies/ml) was the most important risk factor for HBV reactivation after withdrawal of pre-emptive lamivudine on Cox proportional hazards analysis (relative risk 16.13, (95% confidence interval 2.99-87.01; p = 0.001). CONCLUSIONS: HBV reactivation is more likely to occur in patients with high pre-chemotherapy HBV DNA after withdrawal of pre-emptive lamivudine. A more prolonged course of antiviral therapy may be necessary in these patients after completion of chemotherapy in order to reduce post-chemotherapy HBV reactivation.


Subject(s)
Hematologic Neoplasms/drug therapy , Hepatitis B virus/physiology , Hepatitis B/prevention & control , Lamivudine/therapeutic use , Virus Activation/drug effects , Adult , Aged , Antineoplastic Agents/adverse effects , Antiviral Agents/therapeutic use , DNA, Viral/analysis , Female , Follow-Up Studies , Hematologic Neoplasms/complications , Hepatitis B/immunology , Hepatitis B/virology , Hepatitis B Surface Antigens/blood , Hepatitis B virus/isolation & purification , Humans , Immunocompromised Host , Male , Middle Aged
10.
Aliment Pharmacol Ther ; 19(11): 1153-8, 2004 Jun 01.
Article in English | MEDLINE | ID: mdl-15153168

ABSTRACT

BACKGROUND: An increasing proportion of the general population across the Western World now survives to an advanced age. However, there is limited data on the outcome of therapeutic endoscopic retrograde cholangiopancreatography in patients above 90 years of age with severe acute cholangitis. AIM: To determine the relative frequency of postendoscopic retrograde cholangiopancreatography complication in this group of patients. METHODS: The postendoscopic retrograde cholangiopancreatography complications related outcome of 64 patients aged 90 years and above (Group 1) with severe acute cholangitis were retrospectively compared with 165 patients under the age of 90 years (Group 2). RESULTS: The postendoscopic retrograde cholangiopancreatography complication rate was 4.7% (three patients) in Group 1 and 7.3% (12 patients) in Group 2. There was no significant difference in the postendoscopic retrograde cholangiopancreatography complication rate between the two groups (P = 0.567). The relative frequency of 30-day mortality was 7.8% (five patients) in Group 1 and 4.2% (seven patients) in Group 2 (P = 0.227). CONCLUSION: Urgent biliary decompression with endoscopic retrograde cholangiopancreatography in patients 90 years of age and older with severe acute cholangitis is a safe and effective procedure in the hands of highly skilled endoscopists and is not associated with increased morbidity or mortality even in this group of high risk patients.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde/methods , Cholangitis/therapy , Acute Disease , Cholangiopancreatography, Endoscopic Retrograde/mortality , Cholangitis/mortality , Emergencies , Female , Humans , Male , Retreatment , Retrospective Studies , Treatment Outcome
11.
Endoscopy ; 36(3): 206-11, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14986217

ABSTRACT

BACKGROUND AND STUDY AIM: Endoscopic sphincterotomy (ES) or cholecystectomy can prevent recurrent acute pancreatitis (RAP) in patients with gallstone-related pancreatitis. However, it is unknown whether cholecystectomy after ES offers additional benefit in preventing RAP in these patients. This is a retrospective study to assess whether cholecystectomy can decrease the incidence of RAP in patients with gallstone-related pancreatitis. PATIENTS AND METHODS: Records from 139 patients with gallstone-related pancreatitis were analyzed. Of these, 58 patients had gallbladder stones with concomitant common bile duct (CBD) stones and 81 patients had gallbladder stones without CBD stones. Of the 58 patients who had both gallbladder and CBD stones, 37 (63.8 %) did not undergo cholecystectomy after ES (group 1) and 21 patients (36.2 %) did undergo cholecystectomy after ES (group 2). Of the 81 patients who had gallbladder stones but who did not have CBD stones, 54 (66.7 %) did not undergo cholecystectomy (group 3) and 27 (33.3 %) did undergo cholecystectomy (group 4). RESULTS: At the time of analysis, three patients (8.1 %) in group 1 and three patients (14.3 %) in group 2 developed RAP. There was no significant difference in the estimated probability of occurrence of RAP over time between group 1 and group 2 ( P = 0.41). However, there was a significantly higher probability of patients developing RAP over time in group 3 compared with group 4 (6/54 vs. 0/27 respectively, P = 0.04). CONCLUSION: In patients with gallbladder stones without CBD stones, cholecystectomy can decrease the incidence of RAP. In patients with both gallbladder and CBD stones, however, the risk of RAP was not further reduced by cholecystectomy after ES and complete removal of CBD stones.


Subject(s)
Cholecystectomy/methods , Choledocholithiasis/surgery , Pancreatitis/prevention & control , Sphincterotomy, Endoscopic/methods , Aged , Aged, 80 and over , Choledocholithiasis/complications , Female , Humans , Incidence , Male , Middle Aged , Pancreatitis/etiology , Recurrence , Retrospective Studies
12.
Respir Physiol Neurobiol ; 130(2): 169-79, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12380007

ABSTRACT

Pulmonary surfactant is crucial to maintain the proper functioning of the respiration system. Certain types of blood proteins (e.g. albumin) were found to inhibit the activity of pulmonary surfactant. Axisymmetric Drop Shape Analysis (ADSA) was used to study the effect of dextran to restore the activity of an albumin-inhibited pulmonary surfactant. It was found that dextran could effectively restore surface tension properties of the inhibited surfactant in vitro. Furthermore, dextran improved the performance of pulmonary surfactants when albumin was absent. It was found that when a surfactant film was under high compression (e.g. above 70% surface area reduction), the presence of dextran increased film stability, so that the film could sustain high surface pressures without being collapsing.


Subject(s)
Albumins/pharmacology , Dextrans/pharmacology , Pulmonary Surfactants/pharmacology , Dose-Response Relationship, Drug , Pulmonary Surfactants/chemistry , Surface Properties/drug effects , Surface Tension/drug effects , Time Factors
13.
Accid Emerg Nurs ; 10(1): 10-6, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11998578

ABSTRACT

This paper describes the redesign of the triage process in an Emergency Department with the purpose of improving the patient flow and thus increasing patient satisfaction through the reduction of the overall length of stay. The process, Advance Triage, allows the triage nurse to initiate diagnostic protocols for frequently occurring medical problems based on physician-approved algorithms. With staff and physician involvement and medical specialist approval, nine Advance Triage algorithms were developed-abdominal pain, eye trauma, chest pain, gynaecological symptoms, substance abuse, orthopaedic trauma, minor trauma, paediatric fever and paediatric emergent. A comprehensive educational program was provided to the triage nurses and Advance Triage was initiated. A process was established at one year to evaluate the effectiveness of the Advance Triage System. The average length of stay was found to be 46 min less for all patients who were advance triaged with the greatest time-saving of 76 min for patients in the 'Urgent' category. The most significant saving was realized in the patient's length of stay (LOS) after the Emergency Physician assessed them because diagnostic results, available during the initial patient assessment, allowed treatment decisions to be made at that time. Advance Triage utilizes patient waiting time efficiently and increases the nurses' and physicians' job satisfaction.


Subject(s)
Emergency Nursing/methods , Triage/methods , Algorithms , Canada , Clinical Protocols , Emergency Nursing/education , Humans , Program Development/methods , Program Evaluation , Staff Development/methods
14.
Parasitol Res ; 84(9): 741-5, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9766903

ABSTRACT

Bacteriome in the lantern bug Pyrops candelaria harbored a-, t-, and companion bacteroids. The a- and t-bacteroids were irregular bodies, whereas the companion bacteroids were rod-shaped and easily distinguished from the others. The a- and t-bacteroids were enveloped by three membranes and the companion bacteroids, by two membranes. The cytoplasm of the a-bacteroid contained electron-dense bodies.


Subject(s)
Bacteria/cytology , Bacteria/isolation & purification , Insecta/microbiology , Animals , Bacteria/ultrastructure , Microscopy, Electron , Ribosomes/ultrastructure
15.
Parasitol Res ; 83(5): 499-503, 1997.
Article in English | MEDLINE | ID: mdl-9197400

ABSTRACT

The ultrastructure of alpha-bacteroids in relation to the fat-body cells of the lantern bug Pyrops candelaria was described. The fat-body-cell cytoplasm contained numerous mitochondria, rough endoplasmic reticula, vacuoles, and storage granules. Its nucleus had scattered chromatin materials. The alpha-bacteroid was enveloped by three membrane layers, namely, the plasma membrane, the cell wall, and the membrane envelope. Its cytoplasm contained amorphous dense bodies. The bacteroid reproduced by binary fission. Tracheoles were also found among fat-body cells.


Subject(s)
Bacteria/ultrastructure , Fat Body/microbiology , Insecta/microbiology , Symbiosis , Animals , Microscopy, Electron
SELECTION OF CITATIONS
SEARCH DETAIL
...