Browse publications by year: 2019

  1. Balaji G, Sriharsha Y, Sharma D
    Malays Orthop J, 2019 Jul;13(2):49-51.
    PMID: 31467653 DOI: 10.5704/MOJ.1907.010
    A 58-year old female patient presented to us with a three months' old fracture of the neck of femur. She underwent bipolar hemiarthroplasty. In the immediate postoperative period, she developed deep vein thrombosis for which she was started on anticoagulant therapy. Patient had persistent discharge from the wound since then and underwent regular dressings. On the eighth post-op day, she developed sciatic nerve palsy secondary to wound haematoma. The haematoma was decompressed immediately and she had a dramatic improvement in pain but her neurological deficit persisted. The wound healed completely without any complications. At three months follow up, she had recovered completely with grade 5/5 power in ankle and foot and full sensory recovery in the sciatic nerve distribution. She was ambulating comfortably with a walker. At final follow up around 20 months post-operation, she was pain-free and walking without any support. The wound had healed completely.
    MeSH terms: Ankle; Ankle Joint; Anticoagulants; Bandages; Female; Follow-Up Studies; Foot; Hematoma; Humans; Middle Aged; Pain; Sciatic Nerve; Walking; Venous Thrombosis; Sciatic Neuropathy; Hemiarthroplasty
  2. Sahdi H, Rasit AH, Khoo CS, Bojeng A, Nur-Alyana BA
    Malays Orthop J, 2019 Jul;13(2):52-55.
    PMID: 31467654 DOI: 10.5704/MOJ.1907.011
    Congenital humeroradial synostosis can occur as an isolated clinical entity or as part of a syndrome. Bilateral elbow fixed flexion deformity is very incapacitating and challenging to treat. Here we present the case of a boy with fixed flexion deformity of both elbows due bilateral humeroradial synostosis. Other characteristic features of multiple synostoses syndrome were also present in this child, his elder brother and mother. We elected to improve the position of the right elbow by adapting the modified French osteotomy described by Bellemore et al.
    MeSH terms: Child; Elbow; Elbow Joint; Female; Humans; Humerus; Male; Mothers; Osteotomy; Radius; Synostosis; Siblings
  3. Khaw YC, Faisham WI
    Malays Orthop J, 2019 Jul;13(2):56-58.
    PMID: 31467655 DOI: 10.5704/MOJ.1907.012
    Scapular abscess is a rare clinical diagnosis. This is a report of an atypical case of extensive intramuscular scapular abscess involving the anterior and posterior aspects of the scapula with extension into the axillary region following minor trauma in a young healthy adolescent, describing a single posterolateral approach to the scapula to evacuate the abscess. Following surgical drainage and antibiotic treatment, patient recovered without any complication.
    MeSH terms: Abscess; Adolescent; Anti-Bacterial Agents; Axilla; Drainage; Humans; Scapula
  4. Joseph CM, Rama-Prasad YS, Boopalan P, Jepegnanam TS
    Malays Orthop J, 2019 Jul;13(2):59-62.
    PMID: 31467656 DOI: 10.5704/MOJ.1907.013
    This is the first report of a long-term follow-up of an open bicondylar Hoffa with patella fracture. It is interesting to note the radiological changes of osteoarthritis 15 years after global intra-articular injury of the distal femur. The good clinical outcome is possibly due to the integrity of the knee ligaments and reconstruction of the extensor mechanism in addition to stable anatomical reduction and fixation.
    MeSH terms: Femur; Follow-Up Studies; Knee Injuries; Ligaments; Osteoarthritis; Patella; Radiography; Fractures, Bone
  5. Soo CI, Kho SS, Ng BH, Tie ST
    Respirol Case Rep, 2019 Nov;7(8):e00482.
    PMID: 31467678 DOI: 10.1002/rcr2.482
    Endobronchial ultrasound (EBUS) is indispensable when it comes to evaluation of mediastinal lesion and staging of lung cancer. The incorporation of endoscopic ultrasound using an echobronchoscope (EUS-B) further extends this capability to the paraoesophageal and subdiaphragmatic structures. When combined, EBUS with EUS-B increases the diagnostic yield. Both procedures can be done in a single session and by a single operator; this translates into an overall reduction in the healthcare cost.
  6. Wong WF, Chambers JP, Gupta R, Arulanandam BP
    J Pathog, 2019;2019:8604958.
    PMID: 31467721 DOI: 10.1155/2019/8604958
    The increasing number of new cases of Chlamydia infection worldwide may be attributed to the pathogen's ability to evade various host immune responses. Summarized here are means of evasion utilized by Chlamydia enabling survival in a hostile host environment. The pathogen's persistence involves a myriad of molecular interactions manifested in a variety of ways, e.g., formation of membranous intracytoplasmic inclusions and cytokine-induced amino acid synthesis, paralysis of phagocytic neutrophils, evasion of phagocytosis, inhibition of host cell apoptosis, suppression of antigen presentation, and induced expression of a check point inhibitor of programmed host cell death. Future studies could focus on the targeting of these molecules associated with immune evasion, thus limiting the spread and tissue damage caused by this pathogen.
    MeSH terms: Amino Acids; Chlamydia; Chlamydia Infections; Neutrophils; Phagocytes; Phagocytosis; Cytokines; Cell Death; Apoptosis; Antigen Presentation; Immune Evasion
  7. Zakaria ZA, Abdul Rahim MH, Roosli RAJ, Mohd Sani MH, Marmaya NH, Omar MH, et al.
    Biomed Res Int, 2019;2019:6593125.
    PMID: 31467905 DOI: 10.1155/2019/6593125
    Methanolic extract of Clinacanthus nutans Lindau leaves (MECN) has been reported to exert antinociceptive activity. The present study aimed to elucidate the possible antinociceptive mechanisms of a lipid-soluble fraction of MECN, which was obtained after sequential extraction in petroleum ether. The petroleum ether fraction of C. nutans (PECN), administered orally to mice, was (i) subjected to capsaicin-, glutamate-, phorbol 12-myristate 13-acetate-, bradykinin-induced nociception model; (ii) prechallenged (intraperitoneal (i.p.)) with 0.15 mg/kg yohimbine, 1 mg/kg pindolol, 3 mg/kg caffeine, 0.2 mg/kg haloperidol, or 10 mg/kg atropine, which were the respective antagonist of α 2-adrenergic, β-adrenergic, adenosinergic, dopaminergic, or muscarinic receptors; and (iii) prechallenged (i.p.) with 10 mg/kg glibenclamide, 0.04 mg/kg apamin, 0.02 mg/kg charybdotoxin, or 4 mg/kg tetraethylammonium chloride, which were the respective inhibitor of ATP sensitive-, small conductance Ca2+-activated-, large conductance Ca2+-activated-, or nonselective voltage-activated-K+ channel. Results obtained demonstrated that PECN (100, 250, and 500 mg/kg) significantly (P<0.05) inhibited all models of nociception described earlier. The antinociceptive activity of 500 mg/kg PECN was significantly (P<0.05) attenuated when prechallenged with all antagonists or K+ channel blockers. However, only pretreatment with apamin and charybdotoxin caused full inhibition of PECN-induced antinociception. The rest of the K+ channel blockers and all antagonists caused only partial inhibition of PECN antinociception, respectively. Analyses on PECN's phytoconstituents revealed the presence of antinociceptive-bearing bioactive compounds of volatile (i.e., derivatives of γ-tocopherol, α-tocopherol, and lupeol) and nonvolatile (i.e., cinnamic acid) nature. In conclusion, PECN exerts a non-opioid-mediated antinociceptive activity involving mainly activation of adenosinergic and cholinergic receptors or small- and large-conductance Ca2+-activated-K+ channels.
    MeSH terms: Methanol/chemistry; Alkanes/chemistry; Analgesics/pharmacology*; Analgesics/chemistry; Animals; Bradykinin/toxicity; Capsaicin/toxicity; Humans; Plant Extracts/pharmacology*; Plant Extracts/chemistry; Tetradecanoylphorbol Acetate/analogs & derivatives; Tetradecanoylphorbol Acetate/toxicity; Potassium Channels/genetics; Plant Leaves/chemistry; Glutamic Acid/toxicity; Analgesics, Non-Narcotic/pharmacology; Analgesics, Non-Narcotic/chemistry; Acanthaceae/chemistry*; Mice; Nociceptive Pain/chemically induced; Nociceptive Pain/drug therapy*; Nociceptive Pain/pathology
  8. Karim MKA, Sabarudin A, Muhammad NA, Ng KH
    Radiol Phys Technol, 2019 Dec;12(4):374-381.
    PMID: 31468370 DOI: 10.1007/s12194-019-00532-8
    This study aimed to evaluate effective dose and size-specific dose estimate (SSDE) of computed tomography angiography (CTA) examination using an anthropomorphic phantom. We included three CTA examination protocols to evaluate the intra- and extra-cranial arteries, pulmonary artery (CTPA), and abdominal vessels. Patient SSDEs were measured retrospectively to estimate patient dose, relative to the bodyweight of the patient and volume CT dose index (CTDIvol). Our findings revealed that the highest dose was absorbed by the left lobe of the thyroid gland during intra-/extra-cranial CTA and CTPA, that is, 14.11 ± 0.24 mGy and 16.20 ± 3.95 mGy, respectively. However, the highest absorbed dose in abdominal/pelvic CTA was the gonads (8.98 ± 0.30 mGy), while other radiosensitive organs in intra- and extra-cranial CTA, CTPA, and abdominal/pelvic CTA did not demonstrate significant differences between organs/structures with p value 0.88, 0.11, and 0.54, respectively. The estimated effective dose in intra-/extra-cranial CTA was lower in patients (0.80 ± 0.60 mSv) than in the phantom (0.83 mSv), but it was the opposite for CTPA, with the effective dose being higher in patients (7.54 ± 3.09 mSv) than in the phantom (6.68 mSv). Similar to the effective dose, only CTPA SSDEs were significantly higher in men than in women (19.74 ± 4.79 mGy versus 7.9 mGy). Effective dose and SSDE are clinically relevant parameters that can help estimate a more accurate patient dose based on a patient's size.
    MeSH terms: Abdomen/blood supply; Adult; Female; Humans; Lung/blood supply; Male; Pelvis/blood supply; Radiation Dosage*; Retrospective Studies; Skull/blood supply; Phantoms, Imaging*; Computed Tomography Angiography/instrumentation*
  9. Liang T, Qu Q, Chang Y, Gopinath SCB, Liu XT
    Biotechnol Appl Biochem, 2019 Nov;66(6):939-944.
    PMID: 31468573 DOI: 10.1002/bab.1808
    Ovarian cancer starts in the ovaries in its earlier stages and then spreads to the pelvis, uterus, and abdominal region. The success of an ovarian cancer treatment depends on the stage of the cancer and the diagnostic system. Squamous cell carcinoma antigen (SCC-Ag) is one of the most efficient cancer biomarkers, and elevated levels of SCC-Ag in ovarian cancer cells have been used to identify ovarian cancer. Carbon is a potential material for biosensing applications due to its thermal, electrical, and physical properties. Multiwalled carbon nanotubes (MWCNTs) are carbon-based materials that can be used here to detect SCC-Ag. Anti-SCC-Ag antibody was immobilized on the amine-modified MWCNT dielectric sensing surface to detect SCC-Ag. The uniformity of the surface structure was measured with a 3D nanoprofiler, and the results confirmed the detection of SCC-Ag at ∼80 pM. The specific detection of SCC-Ag was confirmed with two control proteins (factor IX and human serum albumin), and the system did not show biofouling. This experimental set-up with MWCNTs a dielectric sensing surface can lead to the detection of ovarian cancer in its initial stages.
    MeSH terms: Amines; Antigens, Neoplasm; Factor IX; Female; Humans; Ovarian Neoplasms; Pelvis; Biomarkers, Tumor; Uterus; Serpins; Nanotubes, Carbon; Biofouling
  10. Arunasalam N
    Nurse Res, 2019 Jun 12;27(2):38-41.
    PMID: 31468887 DOI: 10.7748/nr.2019.e1605
    BACKGROUND: A study was conducted with Malaysian nurses who had studied on an Australian or UK transnational higher education post-registration top-up nursing degree programmes taught by 'flying faculty'.

    AIM: To reflect on the transcription, analysis, interpretation and translation of data in this cross-cultural study.

    DISCUSSION: The findings of this study show how these nurses developed personally and professionally despite challenges, which enabled them to attain a western degree.

    CONCLUSION: Some important aspects of cross-cultural research need to be considered when conducting studies and presenting their findings, as cultural values continue to affect society.

    IMPLICATIONS FOR PRACTICE: The discussion provided will assist novice researchers, nurse research and clinical practice and reviewers of scientific articles when conducting cross-cultural research.

    MeSH terms: Australia; Culture*; Education, Nursing*; Education, Nursing, Continuing*; Great Britain; Humans; Interviews as Topic*; Malaysia; Translating*; Nursing Education Research*; Qualitative Research
  11. Hall DA, Plack CJ
    Hear Res, 2019 10;382:107778.
    PMID: 31470340 DOI: 10.1016/j.heares.2019.107778
    MeSH terms: Animals; Auditory Perception*; Hearing*; Humans; Species Specificity; Persons With Hearing Impairments/psychology; Persons With Hearing Impairments/rehabilitation*; Models, Animal; Hearing Loss/physiopathology; Hearing Loss/psychology; Hearing Loss/rehabilitation*
  12. Abdulwanis Mohamed Z, Mohamed Eliaser E, Mazzon E, Rollin P, Cheng Lian Ee G, Abdull Razis AF
    Molecules, 2019 Aug 27;24(17).
    PMID: 31461914 DOI: 10.3390/molecules24173109
    Plant natural compounds have great potential as alternative medicines for preventing and treating diseases. Melicope lunu-ankenda is one Melicope species (family Rutaceae), which is widely used in traditional medicine, consumed as a salad and a food seasoning. Consumption of different parts of this plant has been reported to exert different biological activities such as antioxidant and anti-inflammatory qualities, resulting in a protective effect against several health disorders including neurodegenerative diseases. Various secondary metabolites such as phenolic acid derivatives, flavonoids, coumarins and alkaloids, isolated from the M. lunu-ankenda plant, were demonstrated to have neuroprotective activities and also exert many other beneficial biological effects. A number of studies have revealed different neuroprotective mechanisms for these secondary metabolites. This review summarizes the most significant and recent studies for neuroprotective activity of M. lunu-ankenda major secondary metabolites in neurodegenerative diseases.
    MeSH terms: Animals; Anti-Inflammatory Agents/pharmacology; Anti-Inflammatory Agents/chemistry; Antioxidants/pharmacology; Antioxidants/chemistry; Humans; Medicine, Traditional; Molecular Structure; Neuroprotective Agents/pharmacology; Neuroprotective Agents/chemistry; Rutaceae/chemistry*; Phytochemicals/pharmacology*; Phytochemicals/chemistry; Secondary Metabolism*
  13. Reshidan NH, Abd Muid S, Mamikutty N
    BMC Complement Altern Med, 2019 Aug 28;19(1):232.
    PMID: 31462242 DOI: 10.1186/s12906-019-2627-0
    BACKGROUND: Metabolic syndrome is a non-communicable disease inclusive of risk factors such as central obesity, hypertension, hyperglycaemia and dyslipidaemia. In this present study, we investigated the ability of Pandanus amaryllifolius (PA) leaf water extract to reverse the cluster of diseases in an established rat model induced by fructose in drinking water.

    METHODS: Thirty healthy adult male Wistar rats (150-180 g) were randomly divided into three groups which included control (C; n = 6), PA extract (PAE; n = 6) and Metabolic Syndrome (MetS; n = 18). Food and fluid were given ad libitum for 8 weeks. These groups differed in fluid intake whereby rats received tap water, 10% of PA leaf water extracts and 20% of fructose in drinking water in group C, PAE and MetS, respectively. After 8 weeks, the MetS group was further subdivided into three subgroups namely MetS1 (n = 6), MetS2 (n = 6) and MetS3 (n = 6). The C, PAE and MetS1 were sacrificed. MetS1 group was sacrificed as the control for metabolic syndrome. MetS2 and MetS3 groups were treated with only tap water and 10% of PA leaf water extract respectively for another 8 weeks. The parameters for physiological and metabolic changes such as obesity, hypertension, hyperglycaemia, dyslipidaemia, and inflammatory biomarkers (NFκβ p65, TNFα, leptin and adiponectin) were measured.

    RESULTS: The intake of 20% of fructose in drinking water induced full blown of metabolic syndrome symptoms, including obesity, hypertension, dyslipidaemia and hyperglycaemia in male Wistar rats. Subsequently, treatment with PA leaf water extract improved obesity parameters including BMI, abdominal adipose tissue deposition and adipocytes size, systolic and diastolic blood pressures, fasting plasma glucose, triglycerides, high density lipoprotein with neutral effects on inflammatory biomarkers.

    CONCLUSIONS: Administration of PA in metabolic syndrome rat model attenuates most of the metabolic syndrome symptoms as well as improves obesity. Therefore, PA which is rich in total flavonoids and total phenolic acids can be suggested as a useful dietary supplement to improve metabolic syndrome components induces by fructose.

    MeSH terms: Animals; Blood Glucose/drug effects; Blood Pressure/drug effects; Disease Models, Animal; Fructose/adverse effects*; Lipids/blood; Male; Plant Extracts/pharmacology*; Plant Extracts/chemistry; Rats, Wistar; Plant Leaves/chemistry; Pandanaceae/chemistry*; Abdominal Fat/drug effects; Rats
  14. Nwozichi CU, Marcial DE, Farotimi AA, Escabarte ABS, Madu AM
    PMID: 31463326 DOI: 10.4103/jehp.jehp_240_18
    BACKGROUND: The integration of information and communication technology (ICT) in education has been a major agenda of the Association of Southeast Asian Nations and its adoption has been found effective in nursing education.

    OBJECTIVE: This study aims to identify and review existing literature on ICT integration in nursing education within the context of Southeast Asia and to identify the themes of these studies, ICT tools of concern and the research methods adopted.

    METHODOLOGY: A systematic review of six eligible literatures was conducted with thematic analysis. The data for this systematic review of literature are from published studies based on the formulated research question. Electronic databases of Medline, Scopus, PubMed, CINAHL, Mendeley, and Google Scholar were searched and literatures retrieved and screened for eligibility. No date limit was considered in the literature search. This systematic review utilized the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

    RESULTS: The studies originated from the Philippines (n = 3), Malaysia (n = 2), and Singapore (n = 1). One study originated from both the Philippines and Thailand. Four themes emerged from the thematic analysis which include: (1) use of ICT to enhance teaching and learning in nursing, (2) challenges with ICT integration in nursing education, (3) attitude and perceptions toward ICT integration in nursing education, and (4) suggestions for improvement. The most important ICT tools were computers, projectors, and internet. Majority of the studies were descriptive quantitative studies.

    CONCLUSION: Despite increasing concern on the use of ICT in Southeast Asia, ICT integration in nursing education has not been given significant attention. Governments of the Southeast Asian countries should provide sufficient support for ICT integration in the various nursing institutions. Institutional administrators are encouraged to key into the ICT trend and render their support when and where necessary.

    MeSH terms: Asia, Southeastern; Attention; Education, Nursing; Government; Malaysia; Philippines; Singapore; Thailand; MEDLINE; Internet; PubMed
  15. Narayanan SN, Jetti R, Kesari KK, Kumar RS, Nayak SB, Bhat PG
    Environ Sci Pollut Res Int, 2019 Oct;26(30):30693-30710.
    PMID: 31463749 DOI: 10.1007/s11356-019-06278-5
    The primary objective of mobile phone technology is to achieve communication with any person at any place and time. In the modern era, it is impossible to ignore the usefulness of mobile phone technology in cases of emergency as many lives have been saved. However, the biological effects they may have on humans and other animals have been largely ignored and not been evaluated comprehensively. One of the reasons for this is the speedy uncontrollable growth of this technology which has surpassed our researching ability. Initiated with the first generation, the mobile telephony currently reaches to its fifth generation without being screened extensively for any biological effects that they may have on humans or on other animals. Mounting evidences suggest possible non-thermal biological effects of radiofrequency electromagnetic radiation (RF-EMR) on brain and behavior. Behavioral studies have particularly concentrated on the effects of RF-EMR on learning, memory, anxiety, and locomotion. The literature analysis on behavioral effects of RF-EMR demonstrates complex picture with conflicting observations. Nonetheless, numerous reports suggest a possible behavioral effect of RF-EMR. The scientific findings about this issue are presented in the current review. The possible neural and molecular mechanisms for the behavioral effects have been proposed in the light of available evidences from the literature.
    MeSH terms: Animals; Anxiety/etiology*; Blood-Brain Barrier/radiation effects; Brain/physiopathology; Brain/radiation effects*; Electromagnetic Fields/adverse effects*; Humans; Learning/radiation effects; Locomotion/radiation effects; Memory/radiation effects*; Radio Waves*; Cell Phones*; Electromagnetic Radiation
  16. Drewnowski A, Tappy L, Forde CG, McCrickerd K, Tee ES, Chan P, et al.
    Asia Pac J Clin Nutr, 2019;28(3):645-663.
    PMID: 31464412 DOI: 10.6133/apjcn.201909_28(3).0025
    BACKGROUND AND OBJECTIVES: Rising obesity in Southeast Asia, one consequence of economic growth, has been linked to a rising consumption of energy from added sugars. This symposium, organized by ILSI Southeast Asia, explored regional issues related to dietary sugars and health and identified ways in which these issues could be addressed by regional regulatory agencies, food producers, and the consumer.

    METHODS AND STUDY DESIGN: Papers on the following topics were presented: 1) current scientific evidence on the effects of sugars and non-caloric sweeteners on body weight, health, and eating behaviors; 2) innovations by food producers to reduce sugar consumption in the region; 3) regional dietary surveillance of sugar consumption and suggestions for consumer guidance. A panel discussion explored effective approaches to promote healthy eating in the region.

    RESULTS: Excessive consumption of energy in the form of added sugars can have adverse consequences on diet quality, lipid profiles, and health. There is a need for better surveillance of total and added sugars intakes in selected Southeast Asian countries. Among feasible alternatives to corn sweeteners (high fructose corn syrup) and cane sugar are indigenous sweeteners with low glycemic index (e.g., coconut sap sugar). Their health benefits should be examined and regional sugar consumption tracked in detail. Product reformulation to develop palatable lower calorie alternatives that are accepted by consumers continues to be a challenge for industry and regulatory agencies.

    CONCLUSIONS: Public-private collaborations to develop healthy products and effective communication strategies can facilitate consumer acceptance and adoption of healthier foods.

    MeSH terms: Asia; Beverages; Dietary Carbohydrates*; Food Analysis*; Food Labeling*; Humans; Obesity; Sweetening Agents*
  17. Lee SWH, Mak VSL, Tang YW
    Br J Clin Pharmacol, 2019 12;85(12):2668-2688.
    PMID: 31465121 DOI: 10.1111/bcp.14101
    AIMS: Pharmacists have been contributing to the care of residents in nursing homes and play a significant role in ensuring quality use of medicine. However, the changing role of pharmacist in nursing homes and their impact on residents is relatively unknown.

    METHODS: Six electronic databases were searched from inception until November 2018 for articles published in English examining the services offered by pharmacists in nursing homes. Studies were included if it examined the impact of interventions by pharmacists to improve the quality use of medicine in nursing homes.

    RESULTS: Fifty-two studies (30 376 residents) were included in the current review. Thirteen studies were randomised controlled studies, while the remainder were either pre-post, retrospective or case-control studies where pharmacists provided services such as clinical medication review in collaboration with other healthcare professionals as well as staff education. Pooled analysis found that pharmacist-led services reduced the mean number of falls (-0.50; 95% confidence interval: -0.79 to -0.21) among residents in nursing homes. Mixed results were noted on the impact of pharmacists' services on mortality, hospitalisation and admission rates among residents. The potential financial savings of such services have not been formally evaluated by any studies thus far. The strength of evidence was moderate for the outcomes of mortality and number of fallers.

    CONCLUSION: Pharmacists contribute substantially to patient care in nursing homes, ensuring quality use of medication, resulting in reduced fall rates. Further studies with rigorous design are needed to measure the impact of pharmacist services on the economic benefits and other patient health outcomes.

    MeSH terms: Accidental Falls/prevention & control; Accidental Falls/statistics & numerical data; Aged; Aged, 80 and over; Health Services for the Aged/organization & administration*; Hospitalization/statistics & numerical data; Humans; Nursing Homes/organization & administration*; Pharmaceutical Services/organization & administration; Pharmaceutical Services/standards; Pharmacists*; Professional Role*; Drug-Related Side Effects and Adverse Reactions/epidemiology; Drug-Related Side Effects and Adverse Reactions/prevention & control
  18. Soper FM, MacKenzie RA, Sharma S, Cole TG, Litton CM, Sparks JP
    Glob Chang Biol, 2019 Aug 29.
    PMID: 31465581 DOI: 10.1111/gcb.14813
    Mangrove forests play an important role in climate change adaptation and mitigation by maintaining coastline elevations relative to sea level rise, protecting coastal infrastructure from storm damage and storing substantial quantities of carbon (C) in live and detrital pools. Determining the efficacy of mangroves in achieving climate goals can be complicated by difficulty in quantifying C inputs (i.e., differentiating newer inputs from younger trees from older residual C pools), and mitigation assessments rarely consider potential offsets to CO2 storage by methane (CH4 ) production in mangrove sediments. The establishment of non-native Rhizophora mangle along Hawaiian coastlines over the last century offers an opportunity to examine the role mangroves play in climate mitigation and adaptation both globally and locally as novel ecosystems. We quantified total ecosystem C storage, sedimentation, accretion, sediment organic C burial and CH4 emissions from ~70 year old R. mangle stands and adjacent uninvaded mudflats. Ecosystem C stocks of mangrove stands exceeded mudflats by 434 ± 33 Mg C ha-1 , and mangrove establishment increased average coastal accretion by 460%. Sediment organic C burial increased 10-fold (to 4.5 Mg C ha-1 yr-1 ), double the global mean for old growth mangrove forests, suggesting that C accumulation from younger trees may occur faster than previously thought, with implications for mangrove restoration. Simulations indicate that increased CH4 emissions from sediments offset ecosystem CO2 storage by only 2-4%, equivalent to 30-60 Mg CO2 -eq ha-1 over mangrove lifetime (100-year sustained global warming potential). Results highlight the importance of mangroves as novel systems that can rapidly accumulate C, have a net positive atmospheric greenhouse gas removal effect, and support shoreline accretion rates that outpace current sea level rise. Sequestration potential of novel mangrove forests should be taken into account when considering their removal or management, especially in the context of climate mitigation goals.
    MeSH terms: Acclimatization; Burial; Carbon; Carbon Dioxide; Goals; Hawaii; Maintenance; Methane; Trees; Ecosystem; Rhizophoraceae; Wetlands; Climate Change; Global Warming
  19. Ait Abderrahim L, Taïbi K, Abderrahim NA, Alomery AM, Abdellah F, Alhazmi AS, et al.
    Toxicon, 2019 Aug 26;169:38-44.
    PMID: 31465783 DOI: 10.1016/j.toxicon.2019.08.005
    Microcystin Leucine-Arginine (MC-LR) is a toxin produced by the cyanobacteria Microcystis aeruginosa. It is the most encountered and toxic type of cyanotoxins. Oxidative stress was shown to play a role in the pathogenesis of microcystin LR by the induction of intracellular reactive oxygen species (ROS) formation that oxidize and damage cellular macromolecules. In the present study we examined the effect of acute MC-LR dose on the cardiac muscle of BALB/c mice. Afterwards, melatonin and N-acetyl cysteine (NAC) were assayed and evaluated as potential protective and antioxidant agents against damages generated by MC-LR. For this purpose, thirty mice were assigned into six groups of five mice each. The effect of MC-LR was first compared to the control group supplied with distilled water, then compared to the other groups supplied with melatonin and NAC. The experiment lasted 10 days after which animals were euthanized. Biomarkers of toxicity such as alkaline phosphatase activity, lipid peroxidation, protein carbonyl content, reduced glutathione content, serum lactate dehydrogenase and serum sorbitol dehydrogenase were assayed. Results showed that toxin treated mice have experienced significant oxidative damage in their myocardial tissue as revealed by noticeable levels of oxidative stress biomarkers and by the reduction in alkaline phosphatase activity. Whereas, melatonin and NAC treated mice manifested lesser oxidative damages. Our findings suggest a potential therapeutic use of melatonin and N-acetyl cysteine as antioxidant protective agents against oxidative damage induced by MC-LR.
    MeSH terms: Acetylcysteine; Cyanobacteria; Alkaline Phosphatase; Animals; Antioxidants; Arginine; Glutathione; L-Iditol 2-Dehydrogenase; Leucine; Melatonin; Mice, Inbred BALB C; Myocardium; Oxidation-Reduction; Lipid Peroxidation; Biomarkers; Reactive Oxygen Species; Oxidative Stress; Control Groups; Lactate Dehydrogenases; Microcystis; Protein Carbonylation; Mice; Microcystins
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