Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
1.
R Soc Open Sci ; 6(12): 191763, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31903217

ABSTRACT

The peeling of small-diameter rubberwood logs from the current short-rotation practices undoubtedly will produce lower grade veneers compared to the veneers from conventional planting rotation. Hence, this raises the question of the properties of the produced laminated veneer lumber (LVL) from veneers peeled from small-diameter rubberwood logs using the spindleless lathe technology. Different thicknesses of rubberwood veneers was peeled from rubberwood logs with diameter less than 20 cm using a spindleless lathe. Three-layer LVLs were prepared using phenol formaldehyde (PF) adhesive and hot pressed at different temperatures. During the peeling of veneer, lathe checks as deep as 30-60% of the veneer thickness are formed. Owing to deeper lathe check on 3 mm rubberwood veneer, higher pressing temperature significantly increased the gluebond shear strength of the PF-bonded LVL. In addition, lathe check frequency was also shown to influence the bond strength. The presence of higher lathe check frequency on 2 mm veneer increased the wettability, thus facilitating optimum penetration of adhesive for stronger bonding. These findings stress the importance of measuring and considering the lathe check depth and frequency during the lamination process to get a better understanding of bonding quality in veneer-based products.

2.
Int J Tuberc Lung Dis ; 22(1): 65-72, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29297428

ABSTRACT

OBJECTIVE: To investigate the prevalence of bacterial co-infection and its effect on early mortality among hospitalised human immunodeficiency virus (HIV) negative pulmonary tuberculosis (PTB) patients in Manila, the Philippines. DESIGN: A prospective observational study was conducted at a national infectious disease hospital. HIV-negative PTB patients aged 13 years hospitalised from November to December 2011 and from December 2012 to May 2013 were enrolled. Sputum samples were tested for Mycobacterium tuberculosis and six respiratory bacterial pathogens using polymerase chain reaction (PCR). RESULTS: Of 466 patients, 228 (48.9%) were TB-PCR-positive. Overall, bacterial pathogens in purulent sputum were detected in 135 (29.0%) patients: Haemophilus influenzae was the most common bacterium (21.2%), followed by Streptococcus pneumoniae (7.9%). The prevalence of bacterial co-infection did not differ between TB-PCR-positive and -negative patients. A total of 92 (19.7%) patients died within 2 weeks. Bacterial co-infection was significantly associated with an increased risk of 2-week mortality among TB-PCR-positive patients (adjusted risk ratio [aRR] 1.67, 95%CI 1.03-2.72). This association was also observed but did not reach statistical significance among TB-PCR-negative patients (aRR1.7, 95%CI 0.95-3.02). CONCLUSION: Bacterial co-infection is common and contributes to an increased risk of early mortality among HIV-negative PTB patients.


Subject(s)
Bacterial Infections/epidemiology , Mycobacterium tuberculosis/isolation & purification , Tuberculosis, Pulmonary/epidemiology , Adolescent , Adult , Bacterial Infections/microbiology , Coinfection , Female , Hospitalization , Humans , Male , Middle Aged , Philippines/epidemiology , Polymerase Chain Reaction , Prevalence , Prospective Studies , Sputum/microbiology , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/mortality , Young Adult
3.
Environ Entomol ; 44(5): 1367-74, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26314017

ABSTRACT

The lower termite, Coptotermes curvignathus, is one of the most prominent plantation pests that feed upon, digest, and receive nourishment from exclusive lignocellulose diets. The objective of this study was to examine the utilization of sole carbon sources by isolated culturable aerobic bacteria among communities from the gut and foraging pathway of C. curvignathus. We study the bacteria occurrence from the gut of C. curvignathus and its surrounding feeding area by comparing the obtained phenotypic fingerprint with Biolog's extensive species library. A total of 24 bacteria have been identified mainly from the family Enterobacteriaceae from the identification of Biolog Gen III. Overall, the bacteria species in the termite gut differ from those of foraging pathway within a location, except Acintobacter baumannii, which was the only bacteria species found in both habitats. Although termites from a different study area do not have the same species of bacteria in the gut, they do have a bacterial community with similar role in degrading certain carbon sources. Sugars were preferential in termite gut isolates, while nitrogen carbon sources were preferential in foraging pathway isolates. The preferential use of specific carbon sources by these two bacterial communities reflects the role of bacteria for regulation of carbon metabolism in the termite gut and foraging pathway.


Subject(s)
Bacteria/isolation & purification , Bacteria/metabolism , Carbon/metabolism , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/metabolism , Isoptera/microbiology , Animals , Bacteria/classification , Ecosystem , Enterobacteriaceae/classification , Gastrointestinal Tract/microbiology , Lignin/metabolism , Malaysia , Nitrogen/metabolism , Symbiosis
5.
Hong Kong Med J ; 17(4): 301-5, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21813899

ABSTRACT

OBJECTIVE: To evaluate the anatomical and functional outcomes following laparoscopic sacrocolpopexy in a local unit. DESIGN: Retrospective case series. SETTING: A regional hospital in Hong Kong. PATIENTS: All women who underwent laparoscopic sacrocolpopexy for symptomatic uterine or post-hysterectomy prolapse from January 2003 to December 2008. MAIN OUTCOME MEASURES: Anatomical outcomes, functional outcomes including complications. RESULTS: A total of 31 patients were recruited. The success rate in treating apical vaginal wall prolapse was 100%. There were no recurrences of vault prolapse (defined as stage II or higher). Approximately 19% of women had anterior vaginal wall prolapse and 23% had urinary stress incontinence postoperatively; 6% had a second operation because of anterior vaginal wall prolapse. The rates of dyspareunia and constipation were low. The mean hospital stay was 4 (range, 2-11) days. Two patients sustained bladder injuries and one rectal injury resulting in a rectovaginal fistula. For three patients the procedure was converted to a laparotomy. CONCLUSIONS: Laparoscopic sacrocolpopexy is feasible in our population and has a high success rate for treating apical vaginal wall prolapse. The incidence of complications was acceptable.


Subject(s)
Gynecologic Surgical Procedures/methods , Hysterectomy/adverse effects , Laparoscopy/methods , Postoperative Complications/surgery , Uterine Prolapse/surgery , Vagina/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Retrospective Studies , Sacrum/surgery , Treatment Outcome
6.
Percept Mot Skills ; 96(3 Pt 1): 1027-39, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12831286

ABSTRACT

Validation of the proportional duration model was attempted using very fast single-joint repetitive horizontal abductive-adductive movements of the stretched upper extremity with minimal cognitive input. Participants drew oscillating horizontal lines during 20 sec. over relatively short distances as quickly as possible without visual feedback. Spatial, temporal, and kinetic parameters were analysed. The amplitude and the time spent accelerating, decelerating, and reversing in both directions of each experimental line were recorded and related to the centre of gravity of the upper extremity. The accelerations of the centre of mass of the upper extremity were calculated and used to calculate the forces involved. The ratios of durations were compared and intercorrelated for the two fastest, two average, and two slowest cycles from each participant. Results exhibited significant standard deviations and variability of temporal and kinetic parameters within individual trials. The number of significant coefficients of correlation within individual trials was small despite the controlling influence of the same generalised motor program. The proportional duration model did not hold for our data. Peripheral factors (probably the length-tension relationship rule for skeletal muscles and viscosity of muscle) may be important in this type of action.


Subject(s)
Hand , Models, Biological , Movement , Periodicity , Biomechanical Phenomena , Body Mass Index , Humans , Psychomotor Performance , Time Factors
7.
Mol Biol Cell ; 11(9): 3219-32, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10982412

ABSTRACT

Podocalyxin is a major membrane protein of the glomerular epithelium and is thought to be involved in maintenance of the architecture of the foot processes and filtration slits characteristic of this unique epithelium by virtue of its high negative charge. However, until now there has been no direct evidence for podocalyxin's function. Podocalyxin is a type 1 transmembrane sialoprotein with an N-terminal mucin-like domain. To assess its function, we cloned rat podocalyxin and examined the effects of its expression on the cell adhesion properties of stably transfected Chinese hamster ovary (CHO)-K1 and Madin-Darby canine kidney (MDCK) cells and inducible ecdysone receptor-expressing (EcR)-CHO cells. In a cell aggregation assay, CHO-K1 cells expressing high levels of podocalyxin showed complete inhibition of cell aggregation, and MDCK transfectants showed greatly reduced aggregation ( approximately 60-80%) compared with parental cells. In EcR-CHO cells, the expression level of podocalyxin induced by increasing levels of ecdysone analogue correlated closely with the antiadhesion effect. The inhibitory effect of podocalyxin was reversed by treatment of the cells with Arthrobacter ureafaciens sialidase, indicating that sialic acid is required for inhibition of cell adhesion. Overexpression of podocalyxin also affected transepithelial resistance and the distribution of junctional proteins in MDCK cells by an unknown mechanism that may involve interaction with the actin cytoskeleton. These results provide direct evidence that podocalyxin functions as an antiadhesin that maintains an open filtration pathway between neighboring foot processes in the glomerular epithelium by charge repulsion.


Subject(s)
Cell Adhesion/physiology , Intercellular Junctions/physiology , Sialoglycoproteins/physiology , Amino Acid Sequence , Animals , Arthrobacter/enzymology , CHO Cells , Cell Aggregation/physiology , Cell Line , Chickens , Cloning, Molecular , Cricetinae , Dogs , Glycosylation , Humans , Kidney , Molecular Sequence Data , Neuraminidase/metabolism , Phosphorylation , Rabbits , Rats , Receptors, Steroid/genetics , Receptors, Steroid/physiology , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid , Sialoglycoproteins/chemistry , Sialoglycoproteins/genetics , Transfection
8.
Am J Physiol ; 275(1): G56-62, 1998 07.
Article in English | MEDLINE | ID: mdl-9655684

ABSTRACT

The carboxy-terminal region of many guanine nucleotide-binding protein (G protein)-coupled receptors contains important regulatory sequences such as an NP(x)2-3Y motif, a site of fatty acid acylation, and serine- and threonine-rich domains. The type A CCK receptor contains all of these, yet their significance has not been examined. We have, therefore, constructed a series of receptor site mutants and truncations that interfere with each of these motifs and expressed each in Chinese hamster ovary cells where they were studied for radioligand binding, cell signaling, receptor internalization, and intracellular trafficking. Each construct was synthesized and transported appropriately to the cell surface, where CCK bound with high affinity, elicited an inositol 1,4, 5-trisphosphate response, and resulted in internalization and normal trafficking. Thus modification or elimination of each of these established sequence motifs had no substantial effect on any of these parameters of receptor and cellular function. However, an additional construct that truncated the carboxy terminus, eliminating an additional 15-amino-acid segment devoid of any currently recognized sequence motifs, resulted in a marked change in receptor trafficking, with all other parameters of receptor function normal. This mutant receptor construct was delayed at the stage of early endosomes, delaying its progress to the lysosome-enriched perinuclear compartment from the rapid time course followed by wild-type receptor and all of the other constructs. It is proposed that this region of the CCK receptor tail contains a new motif important for intracellular receptor trafficking.


Subject(s)
Protein Conformation , Receptors, Cholecystokinin/chemistry , Receptors, Cholecystokinin/physiology , Amino Acid Sequence , Amino Acid Substitution , Animals , CHO Cells , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Cholecystokinin/pharmacology , Cricetinae , GTP-Binding Proteins/metabolism , Inositol 1,4,5-Trisphosphate/metabolism , Models, Molecular , Molecular Sequence Data , Mutagenesis, Site-Directed , Point Mutation , Rats , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Deletion , Signal Transduction , Sincalide/pharmacology , Transfection
9.
Nihon Geka Gakkai Zasshi ; 99(4): 203-7, 1998 Apr.
Article in Japanese | MEDLINE | ID: mdl-9642686

ABSTRACT

Intraoperative hepatic ultrasonography provides a great deal of information about tumor location and vascular anatomy in the liver, and is an indispensable procedure for hepatic resection. However, an accurate three-dimensional understanding of ultrasound (US) images depends on the operator's skill and experience, as the original display is two dimensional. We developed a new three-dimensional US (3D-US) image processing method by application of the intensity projection method to US. The minimum and maximum intensity projection can display the arrangement of blood vessels (hepatic veins and portal veins) and hyperechoic regions, respectively. The intensity projection from several points of view can reconstruct 3D imaging by cine-display. Moving a probe manually, images are taken and processed on a real-time basis (in about 10 seconds). 3D-US was used in 24 patients undergoing hepatic resection, and allowed easy visualization of the tumors and vascular anatomy. It is considered to be an efficient and safe navigation system in liver surgery.


Subject(s)
Hepatectomy/methods , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Monitoring, Intraoperative/methods , Ultrasonography, Interventional/methods , Aged , Carcinoma, Hepatocellular/surgery , Hepatic Veins/diagnostic imaging , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Male , Portal Vein/diagnostic imaging
10.
Korean J Intern Med ; 12(2): 193-200, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9439155

ABSTRACT

OBJECTIVES: This study was undertaken to examine the effect of oxidant on lipid peroxidation and lethal cell injury in rat liver slices. METHODS: t-Butylhydroperoxide (t-BHP) was employed as a model of an oxidant. The lipid peroxidation and lethal cell injury were estimated by measuring the formation of malondialdehyde (MDA) and lactate dehydrogenase (LDH) release, respectively. RESULTS: t-BHP increased lipid peroxidation and LDH release in a dose-dependent manner over concentrations of 0.5-10 mM. t-BHP-induced lipid peroxidation was completely prevented by an antioxidant, N,N-diphenyl-p-phenylenediamine (DPPD), but LDH release was partially decreased. Both t-BHP-induced lipid peroxidation and LDH release were significantly protected by iron chelator, deferoxamine, sulfhydryl reducing agent, dithiothreitol and glutathione. Ca2+ channel blockers, verapamil, diltiazem and nifedipine exerted a significant protective effect against t-BHP-induced lipid peroxidation and LDH release. By contrast, addition of external Ca2+ chelator, ethylene glycol bis(b-aminoethyl ether)-N,N-tetraacetic acid (EGTA) did not alter t-BHP-induced lipid peroxidation, whereas t-BHP-induced lethal cell injury was significantly prevented. Phospholipase A2 (PLA2) inhibitors, mepacrine and butacaine produced a partial protective effect. CONCLUSIONS: These results suggest that t-BHP induces cell injury by lipid peroxidation-dependent and -independent mechanisms which can be partially prevented by Ca2+ channel blockers and PLA2 inhibitors.


Subject(s)
Calcium Channel Blockers/pharmacology , Calcium/metabolism , Enzyme Inhibitors/pharmacology , Lipid Peroxidation/drug effects , Liver/drug effects , Phospholipases A/antagonists & inhibitors , Animals , In Vitro Techniques , L-Lactate Dehydrogenase/metabolism , Liver/metabolism , Male , Peroxides/toxicity , Phospholipases A2 , Rats , Rats, Sprague-Dawley , tert-Butylhydroperoxide
11.
Anal Biochem ; 247(2): 210-5, 1997 May 01.
Article in English | MEDLINE | ID: mdl-9177679

ABSTRACT

Receptor regulation is a key component of the phenomenon of desensitization in response to agonist stimulation which protects cells from overstimulation. Receptor internalization is one part of this response, often quantified by the portion of saturable ligand binding which becomes resistant to acidic washes. It is now clear that this can include receptor in multiple distinct cellular compartments. We have developed a morphological technique involving dual fluorescent probes to delineate the plasmalemma and the ligand-occupied receptor using confocal microscopy, with analysis involving three-dimensional reconstruction and quantitation of receptor movement through each compartment. When a radioiodinated cholecystokinin (CCK) analogue occupied its receptor on the CHO-CCKR cell line, it became progressively more resistant to dissociation with acidic medium. Quantitation of receptor internalization in these cells over time using this dynamic morphological technique correlated with the acid-resistant receptor fraction, and provided the additional information of the cellular compartments traversed. This technique will have multiple applications to explore the cell-specific handling of this and other ligand-occupied receptors.


Subject(s)
Receptors, Cholecystokinin/metabolism , Animals , Biological Transport, Active , CHO Cells , Cricetinae , Fluorescent Dyes , Image Processing, Computer-Assisted , Kinetics , Microscopy, Confocal , Radioligand Assay , Rats , Receptors, Cholecystokinin/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
12.
Ann Acad Med Singap ; 25(5): 679-82, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8924004

ABSTRACT

Clinical experience of arthroscopy in 12 temporomandibular joints with a clinical diagnosis of closed lock was described. There were 10 patients and all were females with a mean age of 31.2 years (range 20 to 59 years). The antero-lateral approach was used for entry into 11 joints. The clinical findings were adhesions (64%), fibrillation (64%), anterior displacement of disc (36%) and scuffing of the articular surface of the glenoid fossa (9%). Two of the joints that had arthrocentesis prior to arthroscopy did not show any different findings from the rest. Of the 8 patients who had pre-arthroscopy pain, 7 patients (88%) had reduction of the symptom. Three patients (38%) had complete resolution of pain. The range of mouth opening (measured as maximal incisor opening) increased in all patients two weeks following arthroscopy. The average change in maximal incisor opening was 40.3% with a range of 22% to 85%. The mean follow-up was 34 months (range 4 to 68 months).


Subject(s)
Arthroscopy , Postoperative Complications/physiopathology , Temporomandibular Joint Dysfunction Syndrome/surgery , Adult , Arthroscopes , Arthroscopy/methods , Female , Follow-Up Studies , Humans , Middle Aged , Range of Motion, Articular , Singapore , Temporomandibular Joint Dysfunction Syndrome/diagnosis
13.
Zhonghua Nei Ke Za Zhi ; 34(8): 540-4, 1995 Aug.
Article in Chinese | MEDLINE | ID: mdl-8697914

ABSTRACT

Two hundred and three cases of PNH diagnosed (according to the National Unified Diagnosed Criteria, 1987) and treated from 1949 to 1992 in Peking Union Medical Hospital were analyzed retrospectively in an attempt to investigate the factors leading to delayed diagnosis. The presenting manifestation was anemia in 56.7% of the patients. Next was hemorrhage (24.6%). Hemoglobinuria was seen only in 12.8% of the cases at the onset. Ham test was persistently negative in 10.4% of the patients. Only one third of all the cases was correctly diagnosed as PNH within one year after onset. Aplastic anemia or anemia of unknown cause was first diagnosed in 60.1% of cases. The heterogeneity of the manifestations and the lack of sensitive and also specific laboratory tests were the factors leading to delayed diagnosis, but negligence of PNH in differential diagnosis seem to be a major the main cause. Constant awareness of the possibility and careful follow-up accompanied with repeated laboratory examinations in a suspected case are crucial for early diagnosis of PNH.


Subject(s)
Hemoglobinuria, Paroxysmal/diagnosis , Adult , Aged , Anemia/diagnosis , Diagnostic Errors , Female , Humans , Male , Middle Aged , Retrospective Studies
14.
Proc Natl Acad Sci U S A ; 91(17): 7990-4, 1994 Aug 16.
Article in English | MEDLINE | ID: mdl-11607491

ABSTRACT

Models of sympatric speciation for phytophagous insects posit a central role for host plant-associated mating as a premating isolating mechanism in lieu of geographic barriers to gene flow. Here, by means of three mark-and-recapture studies, we confirm that host fidelity (i.e., the tendency of an insect to reproduce on the same host species that it used in earlier life-history stages) restricts gene flow between sympatric apple- and hawthorn-infesting races of Rhagoletis pomonella (Diptera: Tephritidae) to approximately 6% per generation. Genetically based differences in host preference, adult eclosion under the "correct" host species, and allochronic isolation contribute to host fidelity in various degrees in the races. The results verify that host-associated adaptation can produce reproductive isolation as a correlated character (a key premise of sympatric speciation). The study also represents one of the few or perhaps only example in animals where the intra-specific isolating effects of specific phenotypes have been quantified in nature.

SELECTION OF CITATIONS
SEARCH DETAIL
...