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1.
Ultraschall Med ; 37(1): 63-7, 2016 Feb.
Article in English | MEDLINE | ID: mdl-25140495

ABSTRACT

PURPOSE: Ultrasound is a well-established imaging modality in the assessment of malignant cervical lymphadenopathy. With the use of Doppler ultrasound, intranodal vascularity can be evaluated. However, the major limitation of ultrasound is operator dependency. Therefore, this study aimed to evaluate and compare the diagnostic accuracy and reliability of the subjective grading and computer-aided approach in assessing intranodal vascularity for the differentiation of benign and malignant lymph nodes. MATERIALS AND METHODS: The present study retrospectively assessed 99 power Doppler ultrasound images of cervical lymph nodes and evaluated the degree of intranodal vascularity using qualitative subjective grading (QSG) and quantitative computer-aided (QCA) methods. The diagnostic accuracy of the two methods in distinguishing metastatic and reactive nodes and their inter- and intra-rater reliability in assessing intranodal vascularity were evaluated and compared. RESULTS: The results showed that the QCA method was more accurate than the QSG method with a significantly higher sensitivity (67.8 % and 61.9 %, respectively, p < 0.05) and specificity (73.3 % and 57.3 %, respectively, p < 0.05). Using the intranodal vascularity index as determined by the QCA approach, the optimum cut-off to differentiate metastatic and reactive cervical lymph nodes was 32 %. The QCA method showed higher inter- and intra-rater reliability than the QSG method. CONCLUSION: In the assessment of the degree of intranodal vascularity, the QCA method was more accurate and reliable than the QSG method in distinguishing metastatic and reactive lymph nodes.


Subject(s)
Image Interpretation, Computer-Assisted/methods , Lymph Nodes/blood supply , Lymphadenopathy/diagnostic imaging , Lymphatic Metastasis/diagnostic imaging , Neoplasm Grading , Otorhinolaryngologic Neoplasms/blood supply , Otorhinolaryngologic Neoplasms/diagnostic imaging , Ultrasonography, Doppler , Biopsy, Fine-Needle , Blood Flow Velocity , Clinical Competence , Diagnosis, Differential , Lymph Nodes/pathology , Lymphatic Metastasis/pathology , Neck/diagnostic imaging , Observer Variation , Otorhinolaryngologic Neoplasms/pathology , Reproducibility of Results , Retrospective Studies
2.
Eur J Gynaecol Oncol ; 37(5): 747-749, 2016.
Article in English | MEDLINE | ID: mdl-29787026

ABSTRACT

Abdominal wall mass is not uncommon in clinic, but it is very rare that germ cell tumors (GCTs) arise in the abdominal wall. The authors review the case of a 34-year-old female with abdominal wall mixed malignant GCT composed of embryonal carcinoma and teratoma and combine the relative literature to explain why GCTs originate from anterior abdominal wall.


Subject(s)
Abdominal Neoplasms/pathology , Abdominal Wall/pathology , Neoplasms, Germ Cell and Embryonal/pathology , Adult , Female , Humans
3.
Int J Clin Pract ; 69(12): 1473-85, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26299643

ABSTRACT

BACKGROUND: An increased risk for ischaemic stroke has been reported in young hyperthyroidism patients independent of atrial fibrillation (AF). However, whether the use of antithyroid drugs in hyperthyroidism patients can reduce the occurrence of ischaemic stroke remains unclear. METHODS: A total of 36,510 newly diagnosed hyperthyroidism patients during 2003-2006 were identified from the Taiwan National Health Insurance Research database. Each patient was individually tracked for 5 years from their index date (beginning the antithyroid drugs) to identify those who suffered from new episode of ischaemic stroke. Medication possession ratio (MPR) was used to represent the antithyroid drug compliance. The association between the MPR and the risk of stroke was examined. RESULTS: The stroke incidence rates for hyperthyroidism patients with age < 45 years and age ≥ 45 years were 0.42 and 3.76 per 1000 person-years, respectively. The patients aged < 45 years with MPR < 0.2 (adjusted hazard ratio, HR, 2.30; 95% CI, 1.13-4.70; p = 0.02) and 0.2 ≤ MPR < 0.4 (adjusted HR, 2.24; 95% CI, 1.06-4.72; p = 0.035) had a significantly increased risk of ischaemic stroke as compared to those with ≥ 0.6. In patients of the age ≥ 45 years, only the patients with MPR < 0.2 (adjusted HR, 1.44; 95% CI, 1.03-2.01; p = 0.036) had a significantly higher risk of ischaemic stroke as compared to those with MPR ≥ 0.6. In hyperthyroidism patients without AF, good antithyroid drugs compliance also reduced the incidence of stroke significantly (adjusted HR, range: 1.52-1.61; p = 0.02); but not in hyperthyroidism with AF. CONCLUSION: Hyperthyroidism patients with good antithyroid drug compliance had a lower risk of ischaemic stroke than patients with poor compliance.


Subject(s)
Antithyroid Agents/therapeutic use , Hyperthyroidism/drug therapy , Medication Adherence , Stroke/epidemiology , Adult , Aged , Female , Humans , Hyperthyroidism/complications , Incidence , Male , Middle Aged , Proportional Hazards Models , Risk Factors , Stroke/etiology , Taiwan/epidemiology , Young Adult
4.
J Appl Microbiol ; 118(4): 826-38, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25641229

ABSTRACT

AIM: The goal of this study was to investigate the synergic effects between magnolol and azoles, and the potential antifungal mechanisms. METHODS AND RESULTS: Microdilution checkerboard, time-kill and agar diffusion assay were employed to evaluate the synergic effects between magnolol and fluconazole (FLC). Magnolol significantly decreased the efflux of rhodamine 123 (Rh123), leading to greater intracellular accumulation of Rh123 in Candida albicans cells. Compared to the Candida drug resistance (cdr) 2 or multidrug resistance (mdr) 1 deletion mutant, the growth of cdr1 strain was most sensitive to magnolol exposure. In the presence of magnolol, MDR1 overexpressing cells were sensitive to FLC, whereas CDR1 and CDR2 overexpressing cells displayed tolerance to FLC. Magnolol treatment correlated with up-regulation of transporter and ergosterol biosynthesis pathway genes, analyzed by real-time reverse transcription-polymerase chain reaction. The ergosterol content of C. albicansSC5314 was significantly decreased after magnolol exposure. CONCLUSIONS: Magnolol synergizes with azoles for targeting of C. albicans by inducing a higher intracellular content of antifungals, by tapping into the competitive effect of ABC transporter Cdr1p substrates, and enhancing the effect by targeting of the ergosterol biosynthesis pathway. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provide the first evidence that magnolol may function as a Cdr1p substrate and as an inhibitor of ergosterol biosynthesis. This function can thus be exploited in combination with azoles to reverse multidrug resistance of C. albicans strains.


Subject(s)
Antifungal Agents/pharmacology , Azoles/pharmacology , Biphenyl Compounds/pharmacology , Candida albicans/drug effects , Lignans/pharmacology , Candida albicans/genetics , Candida albicans/metabolism , Drug Synergism , Ergosterol/biosynthesis , Fluconazole/pharmacology , Fungal Proteins/genetics , Fungal Proteins/metabolism , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Up-Regulation/drug effects
5.
Prog Neuropsychopharmacol Biol Psychiatry ; 34(6): 1098-103, 2010 Aug 16.
Article in English | MEDLINE | ID: mdl-20541579

ABSTRACT

Weight gain induced by atypical antipsychotics causes a serious health concern in the treatment of schizophrenic patients. In the present study chronic treatment of female Wistar rats with olanzapine caused weight gain, but limited effect on food intake. A dramatic drug-induced morphological change of the subcutaneous adipose tissue was observed, i.e. development of a pinkish coloration with the appearance of a "fish egg"-like texture. Histological examination revealed a massive increase in the proliferation of undifferentiated adipocytes. Such proliferation was detected as early as the third day after olanzapine treatment. The changes progressed in a time- and dose-dependent manner. The proliferation of adipose tissue was detected in rats treated with olanzapine independent of increases in weight gain. Protein profiles of the adipose tissue were also altered by olanzapine. These results suggest that olanzapine-induced weight gain may be not solely due to an effect on behavioural satiety. The potential involvement of adipose neuronal input and proliferation are discussed.


Subject(s)
Adipocytes/drug effects , Benzodiazepines/pharmacology , Cell Proliferation/drug effects , Subcutaneous Fat/drug effects , Adipocytes/cytology , Adiposity/drug effects , Analysis of Variance , Animals , Antipsychotic Agents/pharmacology , Dose-Response Relationship, Drug , Eating/drug effects , Female , Olanzapine , Rats , Rats, Wistar , Subcutaneous Fat/cytology
6.
East Asian Arch Psychiatry ; 20(4): 155-62, 2010 Dec.
Article in English | MEDLINE | ID: mdl-22348923

ABSTRACT

OBJECTIVES: To explore the preparedness of medical students towards advance directives and related end-of-life issues, and to examine background factors such as knowledge, attitudes, and experience concerning advance directives and related end-of-life issues. METHODS: In 2007, 448 medical students in years 3 to 5 were surveyed at the Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong. Their knowledge, attitudes, and experiences of advance directives and related end-of-life issues, and their self-perceived preparedness to discuss these matters with patients were evaluated. RESULTS: A total of 220 (49%) of the eligible students responded, of whom 79% supported the use of advance directives. Only 65 (30%) students were certain of what advance directives meant and 198 (90%) students felt that their knowledge of advance directives was inadequate. Also, 197 (90%) students felt unprepared about advance directives and end-of-life issues. Factors associated with positive attitude towards advance directives included religion and knowledge. No factors were found to be associated with self-perceived preparedness towards advance directives or end-of-life issues. CONCLUSIONS: Most of the medical students surveyed demonstrated a positive attitude towards advance directives and recognised the importance of advance directives. However, they felt that they were unprepared and lacking in knowledge and experience of advance directives and end-of-life issues. Wider range and more depth of education is needed to better equip medical students for future practice.

8.
J Environ Sci (China) ; 21(8): 1148-52, 2009.
Article in English | MEDLINE | ID: mdl-19862931

ABSTRACT

This is the first detailed characterization of the airborne bacterial profiles in indoor environments. Two restaurants were selected for this study. Fifteen genera of bacteria were isolated from each restaurant and identified by three different bacterial identification systems including MIDI, Biolog and Riboprinter. The dominant bacteria of both restaurants were Gram-positive bacteria in which Micrococcus and Bacillus species were the most abundant. Most bacteria identified were representative species of skin and respiratory tract of human, and soil. Although the bacterial levels in these two restaurants were below the limit of the Hong Kong Indoor Air Quality Objective (HKIAQO) Level 1 standard (i.e., < 500 cfu/m3), the majority of these bacteria were opportunistic pathogens. These results suggested that the identity of airborne bacteria should also be included in the IAQ to ensure there is a safety guideline for the public.


Subject(s)
Air Microbiology , Air Pollution, Indoor/analysis , Bacteria/isolation & purification , Environmental Monitoring , Restaurants , Humans
9.
Phytomedicine ; 16(5): 426-36, 2009 May.
Article in English | MEDLINE | ID: mdl-19109000

ABSTRACT

In this study, we evaluated the pharmacological effects of Ganoderma lucidum (G. lucidum) (water-extract) (0.003, 0.03 and 0.3g/kg, 4-week oral gavage) consumption using the lean (+db/+m) and the obese/diabetic (+db/+db) mice. Different physiological parameters (plasma glucose and insulin levels, lipoproteins-cholesterol levels, phosphoenolpyruvate carboxykinase (PEPCK), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG CoA reductase) and isolated aorta relaxation of both species were measured and compared. G. lucidum (0.03 and 0.3g/kg) lowered the serum glucose level in +db/+db mice after the first week of treatment whereas a reduction was observed in +db/+m mice only fed with 0.3g/kg of G. lucidum at the fourth week. A higher hepatic PEPCK gene expression was found in +db/+db mice. G. lucidum (0.03 and 0.3g/kg) markedly reduced the PEPCK expression in +db/+db mice whereas the expression of PEPCK was attenuated in +db/+m mice (0.3g/kg G. lucidum). HMG CoA reductase protein expression (in both hepatic and extra-hepatic organs) and the serum insulin level were not altered by G. lucidum. These data demonstrate that G. lucidum consumption can provide beneficial effects in treating type 2 diabetes mellitus (T2DM) by lowering the serum glucose levels through the suppression of the hepatic PEPCK gene expression.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/therapeutic use , Phytotherapy , Plant Extracts/therapeutic use , Protein Serine-Threonine Kinases/metabolism , Reishi , Abdominal Fat/drug effects , Animals , Antioxidants/pharmacology , Antioxidants/therapeutic use , Body Weight/drug effects , Cholesterol/blood , Diabetes Mellitus, Experimental/blood , Energy Intake/drug effects , Hydroxymethylglutaryl CoA Reductases/metabolism , Hypoglycemic Agents/pharmacology , Insulin/blood , Lipolysis/drug effects , Lipoproteins/blood , Mice , Obesity/drug therapy , Plant Extracts/pharmacology , Vasodilation/drug effects
10.
Inflammopharmacology ; 16(5): 201-7, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18815744

ABSTRACT

Chinese medicated diet is an everyday practice in China. In this study, 16 commonly used soup making tonic Chinese medicinal herbs were selected for antioxidative capacities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP), and the total phenolic contents of these herbal extracts were measured by the Folin-Ciocalteu method. It confirmed that drinking tonic soups could supplement total antioxidants intake. Amongst the tested herbal extracts, extracts of Canarium album Raeusch., Flos caryophylli and Fructus amomi were found to have the highest antioxidative activities in both DPPH and FRAP assays. Their antioxidative activities were comparable to ascorbic acid and butylated hydroxytoluene. Thus, these herbs are safe and inexpensive sources of natural antioxidants. A significant relationship between the antioxidative effects and total phenolic contents were found, indicating phenolic compounds are the major contributor of antioxidative capacities of these herbs. In addition, a strong correlation between DPPH assay and FRAP assay implied that antioxidants in these herbs were capable of scavenging free radicals and reducing oxidants.


Subject(s)
Antioxidants/pharmacology , Flavonoids/pharmacology , Phenols/pharmacology , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , China , Flavonoids/analysis , Free Radical Scavengers/pharmacology , Phenols/analysis , Polyphenols
11.
Neuropathol Appl Neurobiol ; 34(2): 194-204, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17971074

ABSTRACT

Semicarbazide-sensitive amine oxidase (SSAO) catalyses the oxidative deamination of a variety of endogenous substrates, such as methylamine and aminoacetone, to produce highly reactive aldehydes, which are capable of inducing protein cross-linkage, beta amyloid (Abeta) aggregation and advanced glycation end-product formation. In the brain, SSAO is exclusively located on the blood vessels. Deposits of Abeta, the hallmark of Alzheimer's disease (AD), are closely associated with cerebral blood vessels, that is, cerebral amyloid angiopathy (CAA). In the present study, we examined whether SSAO-mediated deamination contributes to CAA in AD. We employed immunohistochemistry to examine the colocalization of SSAO and Abeta in post mortem brains of AD patients. To assess the role of SSAO-mediated deamination in the deposition of Abeta on blood vessel walls, we developed an in vitro blood vessel model using sections of human umbilical cord. We found a strong expression of SSAO colocalized with Abeta deposits on the blood vessels in AD brains. We also demonstrated that SSAO-mediated deamination increases the deposition of Abeta onto blood vessel walls. Our results support the hypothesis that cerebral vascular SSAO-catalysed deamination contributes to CAA in AD brains.


Subject(s)
Alzheimer Disease/enzymology , Amine Oxidase (Copper-Containing)/metabolism , Amyloid beta-Peptides/metabolism , Cerebral Amyloid Angiopathy/enzymology , Aged , Aged, 80 and over , Blood Vessels/enzymology , Brain/blood supply , Brain/metabolism , Brain/pathology , Female , Humans , Immunohistochemistry , Male , Umbilical Cord
12.
J Neural Transm (Vienna) ; 114(6): 835-9, 2007.
Article in English | MEDLINE | ID: mdl-17401529

ABSTRACT

Formaldehyde and methylglyoxal are generated via deamination from methylamine and aminoacetone respectively catalyzed by semicarbazide-sensitive amine oxidase (SSAO). Malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are end products of lipid peroxidation due to oxidative stress. These aldehydes are capable of inducing protein cross-linkage. Elevated levels of aldehydes were found in Alzheimer's disease (AD). These reactive metabolites may potentially play important roles in beta-amyloid (Abeta) aggregation related to the pathology of AD. In the present study thioflavin-T (ThT) fluorometry, an immuno-dot-blot assay and atomic force microscopy (AFM) were employed to reveal the effect of aldehydes on Abeta aggregation in vitro. The target on Abeta for interaction with formaldehyde was identified. The results support the involvement of endogenous aldehydes in amyloid deposition related to AD.


Subject(s)
Aldehydes/metabolism , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Oxidative Stress/physiology , Plaque, Amyloid/metabolism , Alzheimer Disease/physiopathology , Animals , Deamination , Formaldehyde/metabolism , Humans , Malondialdehyde/metabolism , Pyruvaldehyde/metabolism
13.
Bioresour Technol ; 98(8): 1690-3, 2007 May.
Article in English | MEDLINE | ID: mdl-16844370

ABSTRACT

Polyhydroxyalkanoates (PHAs) production was carried out under various C:N ratios. A ratio of 100 resulted best polymer yield. C-source was an important factor in synthesis. For example, as the ratio of valeric acid (C5) to butyric acid (C4) in N-free medium was increased, the mole fraction of HV in the copolymer increased. When soy waste was used as a C-source a copolymer, a high HV mole fraction (HB:HV, 75:25) was produced while when malt waste was used, a much lower HV mole fraction (HB:HV, 90:10) was generated. It was concluded that activated sludge bacteria could be induced to produce PHAs using food wastes as C-sources and this could be the basis for production of biodegradable plastics.


Subject(s)
Alcaligenes/metabolism , Bioreactors , Fermentation , Polymers/metabolism , Refuse Disposal/methods , Alcaligenes/physiology , Biosynthetic Pathways/physiology , Carbon/metabolism , Chromatography, Gas , Hong Kong , Nitrogen/metabolism
14.
Appl Biochem Biotechnol ; 121-124: 289-301, 2005.
Article in English | MEDLINE | ID: mdl-15917607

ABSTRACT

Accumulation of poly hydroxyalkanoate (PHA) from excess activated sludge (EAS) was monitored and controlled via the oxidation-reduction potential (ORP) adjusting process. The ORP was adjusted and controlled by only regulating the gas-flow rate pumped into the cultural broth in which sodium acetate (C2) and propionate (C3) were used as carbon sources. Productivity of PHA and the PHA compositions at various C2 to C3 ratios were also investigated. When ORP was maintained at +30 mV, 35% (w/w) of PHA of cell dry weight obtained when C2 was used as sole carbon source. The PHA copolymer, poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), accumulated by EAS with different 3-hydroxyvalarate (3HV) molar fractions ranged from 8% to 78.0% when C2 and C3 was used as sole carbon source, By using ORP to monitor and control the fermentation process instead DO meter, the ORP system provided more precise control to the PHA accumulation process from EAS under low dissolved oxygen (DO) concentrations. Adjusting the C2 to C3 ratios in the media could control the composition such as the 3HV/3HB ratios of the PHBV. Furthermore, it might be an effective way to adjust the 3HV molar fractions in PHBV by controlling the DO concentration via the ORP monitoring system. The 3HV molar fractions in the PHBV declined with increasing ORP from -30 mV to +100 mV by adjusting the gas-flow rate (i.e. the DO concentration). It is concluded that the DO plays a very important role in the synthesis of 3HV subunits in PHBV co-polymer from the EAS. Therefore, a hypothetic metabolic model for PHA synthesis from EAS was proposed to try to explain the results in this study.


Subject(s)
Acetates/metabolism , Bacteria, Anaerobic/metabolism , Cell Culture Techniques/methods , Hydroxybutyrates/metabolism , Oxygen/metabolism , Polyesters/metabolism , Propionates/metabolism , Sewage/microbiology , Bacteria, Anaerobic/growth & development , Bioreactors/microbiology , Carbon/metabolism , Hydroxybutyrates/isolation & purification , Industrial Waste/prevention & control , Oxidation-Reduction , Pilot Projects , Polyesters/isolation & purification , Refuse Disposal/methods
15.
Neuroscience ; 133(2): 405-11, 2005.
Article in English | MEDLINE | ID: mdl-15878643

ABSTRACT

Glial cells interact with neurons and play important roles in the development, differentiation, maintenance and repair of the nervous system. Human neuroblastoma cells (SH-SY5Y) became dramatically resistant to neurotoxin 6-hydroxydopamine (6-OHDA), when co-cultured with mouse astrocytes. In order to further delineate the molecular mechanism involved in the neuroprotection in this selective cell-cell interaction, we assessed the activation of two signal pathways, namely, the MAP kinases (extracellular signal-regulated kinases, ERK1/2) and phosphoinositide 3-kinase (PI3-K)/Akt signal pathways in response to 6-OHDA insult and subsequent neuronal survival. Western blot revealed that 6-OHDA significantly increased the phosphorylation of ERK1/2 and Akt in mono-cultured SH-SY5Y cells. However, the increase in ERK1/2 in SH-SY5Y cells after co-cultured with astrocytes occurred as early as 3 h after 6-OHDA treatment in oppose to the increase after 12 h in monocultures. The phosphorylation of Akt in the co-cultured SH-SY5Y cells was much pronounced 3 h after 6-OHDA treatment compared with that in the mono-cultured cells. The anti-apoptotic protein bcl-2 was also increased in the co-cultured SH-SY5Y cells 3 h after treatment with 6-OHDA. Selective inhibitor of PI3-K/Akt signal pathway blocked the acquired resistance to 6-OHDA in SH-SY5Y cells following interaction with astrocytes. Inhibition of ERK1/2 signal pathway did not affect the cell survival. Our data suggest that PI3-K/Akt signal pathway, but not ERK1/2, is involved the acquired resistance in SH-SY5Y cells following cell-cell interaction with astrocytes against the neurotoxic 6-OHDA insult.


Subject(s)
Astrocytes/physiology , Cell Communication/drug effects , Mitogen-Activated Protein Kinases/metabolism , Oxidopamine/toxicity , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Signal Transduction/drug effects , Adrenergic Agents/toxicity , Blotting, Western/methods , Cell Communication/physiology , Cell Line, Tumor , Cell Survival/drug effects , Coculture Techniques/methods , Drug Interactions , Enzyme Inhibitors/pharmacology , Humans , Neuroblastoma , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt , Proto-Oncogene Proteins c-bcl-2/metabolism , Signal Transduction/physiology , Time Factors
16.
Water Res ; 37(3): 561-8, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12688690

ABSTRACT

A gram-negative bacterium Pseudomonas putida 5-x with high Cu2+ accumulating capability was isolated from electroplating effluent in Kwun Tong, Hong Kong. The pretreated cells without superficial layer-capsule, isolated cell envelopes and the separated peptidoglycan layer materials were obtained from fresh P. putida 5-x cells, their Cu2+ adsorption capacities and properties were compared with that of the fresh cells. Pretreatment by 0.1 mol L(-1) HCl enhanced Cu2+ adsorption capacity due to the degradation of cell superficial layer-capsule of P. putida 5-x cells. Isolated cell envelopes possessed five times more Cu2+ adsorption capacity than that of fresh intact cell. The Cu2+ adsorption of separated peptidoglycan layer materials indicated that the peptidoglycan layer only played 10-15% part of the Cu2+ adsorption capacity, and implied other cell surface components such as outer membrane or inner membrane might play an important role in such high Cu2+ binding of the cell envelopes. The adsorption process of fresh cells, pretreated cells and cell envelopes of P. putida 5-x could be described with Freundlich isotherm, while the adsorption of Cu2+ by separated peptidoglycan layer materials was better described with Langmuir isotherm.


Subject(s)
Copper/pharmacokinetics , Pseudomonas putida/physiology , Water Pollutants/pharmacokinetics , Water Purification/methods , Adsorption , Electroplating , Industrial Waste , Temperature
17.
Article in English | MEDLINE | ID: mdl-12680580

ABSTRACT

Ni2+ and Cu2+ are the major heavy metal ions in electroplating wastewater of Hong Kong. In the present study, Pseudomonas putida 5-x cell biomass was used to remove Ni2+ from electroplating effluent. Ni2+ adsorption capacity of P. putida 5-x cell biomass cultured in sulphate-limiting medium was found to be minimum in early logarithmic growth phase, and maximum of 28.1 mg g(-1) in late stationary growth phase. Pretreated cells by 0.1 mol L(-1) HCl could greatly enhance the Ni2+ adsorption capacity of cell biomass from 28.1 to 36.7 mg g(-1) and had no significant effect on biomass loss. The adsorption process of P. putida 5-x fresh cells and pretreated cell all could be expressed with Freundlich isotherm. TEM analyses indicated that acidic pretreatment degraded the superficial layer-capsule outside of the fresh cell to improve the adsorption capacity of cell to Ni2+. The Ni2+ bound by P. putida 5-x cell biomass could be efficiently recovered using 0.1 mol L(-1) HCl, and the cell biomass could be reused at least five cycles for Ni2+ removal and recovery with 93% above removal efficiency and 98% above recovery rate. Owing to the Cu2+ presented in electroplating wastewater inhibiting Ni2+ adsorption process by P. putida 5-x cell biomass, two-stage biosorption processes should be designed to remove and recover Cu2+ and Ni2+ sequentially from electroplating effluent.


Subject(s)
Nickel/isolation & purification , Pseudomonas putida/physiology , Waste Disposal, Fluid , Water Purification/methods , Adsorption , Biodegradation, Environmental , Biomass , Electroplating , Nickel/chemistry
18.
Diabetologia ; 45(9): 1255-62, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12242458

ABSTRACT

AIMS/HYPOTHESIS: Semicarbazide-sensitive amine oxidase has been recognised to be a potential risk factor in vascular disorders associated with diabetic complications and to be related to mortality in patients suffering from heart disease. This enzyme, associated with the vascular system, catalyses the deamination of methylamine and aminoacetone, and also acts as an adhesion molecule related to leucocyte trafficking and inflammation. The deaminated products include the toxic aldehydes, formaldehyde and methylglyoxal, respectively, hydrogen peroxide and ammonia. MATERIALS AND METHODS: In this study, the KKAy mouse, a strain possessing features closely resembling those of Type II (non-insulin-dependent) diabetes mellitus has been used to substantiate the hypothesis. Vascular lesions were induced via chronic feeding of a high cholesterol diet. RESULTS: Both MDL-72974A, a selective mechanism-based semicarbazide-sensitive amine oxidase inhibitor and aminoguanidine effectively inhibited aorta semicarbazide-sensitive amine oxidase activity, and caused a substantial increase in urinary methylamine, and a decrease in formaldehyde and methylgloxal levels. Inhibition of semicarbazide-sensitive amine oxidase also reduced oxidative stress, as shown by a reduction of malondialdehyde excretion. Both MDL-72974A and aminoguanidine reduced albuminuria, proteinuria and the number of atherosclerotic lesions in animals fed with a cholesterol diet over a period of treatment for 16 weeks. CONCLUSION/INTERPRETATION: Increased semicarbazide-sensitive amine oxidase-mediated deamination could be involved in the cascade of atherogenesis related to diabetic complications.


Subject(s)
Albuminuria/physiopathology , Amine Oxidase (Copper-Containing)/metabolism , Arteriosclerosis/physiopathology , Cholesterol, Dietary , Diabetes Mellitus, Type 2/physiopathology , Diabetic Angiopathies/physiopathology , Albuminuria/epidemiology , Allyl Compounds/pharmacology , Amine Oxidase (Copper-Containing)/antagonists & inhibitors , Amines/metabolism , Animals , Arteriosclerosis/urine , Butylamines/pharmacology , Diabetes Mellitus, Type 2/urine , Diabetic Angiopathies/urine , Diet, Atherogenic , Disease Models, Animal , Enzyme Inhibitors/pharmacology , Female , Guanidines/pharmacology , Methylamines/urine , Mice , Mice, Inbred Strains
19.
J Neurosci ; 21(24): 9867-76, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11739594

ABSTRACT

Cannabis (i.e., marijuana and cannabinoids) is the most commonly used illicit drug in developed countries, and the lifetime prevalence of marijuana dependence is the highest of all illicit drugs in the United States. To provide clues for finding effective pharmacological treatment for cannabis-dependent patients, we examined the effects and possible mechanism of lithium administration on the cannabinoid withdrawal syndrome in rats. A systemic injection of the mood stabilizer lithium, at serum levels that were clinically relevant, prevented the cannabinoid withdrawal syndrome. The effects of lithium were accompanied by expression of the cellular activation marker Fos proteins within most oxytocin-immunoreactive neurons and a significant increase in oxytocin mRNA expression in the hypothalamic paraventricular and supraoptic nuclei. Lithium also produced a significant elevation of oxytocin levels in the peripheral blood. We suggest that the effects of lithium against the cannabinoid withdrawal syndrome are mediated by oxytocinergic neuronal activation and subsequent release and action of oxytocin within the CNS. In support of our hypothesis, we found that the effects of lithium against the cannabinoid withdrawal syndrome were antagonized by systemic preapplication of an oxytocin antagonist and mimicked by systemic or intracerebroventricular injection of oxytocin. These results demonstrate that oxytocinergic neuronal activation plays a critical role in the action of lithium against the cannabinoid withdrawal syndrome in rats, thus providing a potentially novel strategy for the treatment of cannabis dependence in humans.


Subject(s)
Brain/drug effects , Cannabinoids/adverse effects , Lithium/pharmacology , Substance Withdrawal Syndrome/prevention & control , Animals , Behavior, Animal/drug effects , Brain/cytology , Brain/metabolism , Camphanes/pharmacology , Cannabinoids/pharmacology , Densitometry , Dose-Response Relationship, Drug , Dronabinol/adverse effects , Dronabinol/analogs & derivatives , Dronabinol/pharmacology , Immunohistochemistry , In Situ Hybridization , Lithium/blood , Male , Morpholines/metabolism , Morpholines/pharmacokinetics , Neurons/drug effects , Neurons/metabolism , Oxytocin/pharmacology , Piperazines/pharmacology , Proto-Oncogene Proteins c-fos/metabolism , Pyrazoles/metabolism , Pyrazoles/pharmacokinetics , Radioimmunoassay , Rats , Rats, Long-Evans , Receptors, Cannabinoid , Receptors, Drug/metabolism , Receptors, Oxytocin/antagonists & inhibitors , Substance Withdrawal Syndrome/blood , Substance Withdrawal Syndrome/etiology
20.
J Diabetes Complications ; 15(5): 250-6, 2001.
Article in English | MEDLINE | ID: mdl-11522499

ABSTRACT

Plasma activity of the enzyme semicarbazide-sensitive amine oxidase (SSAO) is high in diabetes. Production of angiotoxic substances (an aldehyde, hydrogen peroxide, and ammonia) in vessel walls is catalysed by SSAO, suggesting a role for SSAO in the development of complications of diabetes. The objective of the present study was to follow up plasma SSAO activity (measured radiometrically), HbA(1c) (using ion exchange chromatography), and retinopathy (by fundus photography) after 2.8 years, in 34 patients with Type 2 diabetes. We also measured urinary levels of an SSAO substrate, methylamine, by fluorometric high-performance liquid chromatography (HPLC). As at baseline, plasma SSAO activity was now higher in subjects with retinopathy (mean 19.5) than in subjects without retinopathy (mean 16.0), 95% confidence interval (CI) for difference 0.6-6.3 nmol benzylamine ml(-1) plasma h(-1). SSAO activity had not changed significantly since baseline, mean difference -1.65 and 95% CI for difference -3.76 to 0.46 nmol benzylamine ml(-1) plasma h(-1). Mean HbA(1c) level remained higher for patients with retinopathy (now 7.9%) compared to those without retinopathy (6.1%), 95% CI for difference 0.6-3.0%. Comparing baseline and the present study, retinopathy was nonproliferative; level had worsened for five and improved for two patients. Urinary methylamine/creatinine ratio was lower in the group of patients with retinopathy (mean 0.99) than in those without retinopathy (mean 1.78), 95% CI for difference 0.1-1.5 microg mg(-1). The results of the present study are compatible with a role for SSAO in the development of diabetic retinopathy.


Subject(s)
Amine Oxidase (Copper-Containing)/blood , Diabetes Mellitus, Type 2/blood , Diabetic Retinopathy/blood , Diabetic Retinopathy/pathology , Aged , Creatinine/blood , Creatinine/urine , Diabetes Mellitus, Type 2/urine , Diabetic Retinopathy/urine , Female , Follow-Up Studies , Fundus Oculi , Glycated Hemoglobin/analysis , Humans , Male , Methylamines/urine , Middle Aged , Photography
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