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1.
Med J Malaysia ; 76(6): 930-932, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34806689

ABSTRACT

Functional neurological disorder (FND) is a rare neuropsychiatric illness that commonly presents to the medical setting as opposed to the psychiatric setting. FND is characterised by signs and symptoms affecting the voluntary motor or sensory function that cannot be explained by a specific neurological or general medical condition. FND in pregnancy and postpartum is rare. We report here a case of FND in a 32-year-old woman who presented with multiple medical problems during her perinatal period. She exhibited 'la belle indifference', history of vague unexplained medical symptomatology while all relevant investigations were normal. There were longstanding psychosocial and interpersonal difficulties with significant distress including multiple personal, marital, and family issues which stemmed from her childhood. This left her feeling inadequate as a mother to her infant. The diagnosis of FND was finalised by the multidisciplinary team consisting of a neurologist, physicians, and psychiatrists, based on longitudinal assessment. Psychological intervention for the patient included psychoeducation, supportive psychotherapy, stress management, and parental intervention. The key point in our management of the patient was the delivery of the diagnosis to help her understand the illness and treatment plan. For this patient, functional and psychological recovery is achievable with a good therapeutic alliance, early diagnosis of the illness, and the acceptance of her diagnosis.


Subject(s)
Conversion Disorder , Adult , Child , Conversion Disorder/diagnosis , Conversion Disorder/psychology , Female , Humans , Marriage , Pregnancy
2.
Anal Biochem ; 544: 98-107, 2018 03 01.
Article in English | MEDLINE | ID: mdl-29305096

ABSTRACT

With the emergence of multi- and extensive-drug (MDR/XDR) resistant Mycobacterium tuberculosis (M. tb), tuberculosis (TB) persists as one of the world's leading causes of death. Recently, isothermal DNA amplification methods received much attention due to their ease of translation onto portable point-of-care (POC) devices for TB diagnosis. In this study, we aimed to devise a simple yet robust detection method for M. tb. Amongst the numerous up-and-coming isothermal techniques, Recombinase Polymerase Amplification (RPA) was chosen for a real-time detection of TB with or without MDR. In our platform, real-time RPA (RT-RPA) was integrated on a lab-on-a-disc (LOAD) with on-board power to maintain temperature for DNA amplification. Sputa collected from healthy volunteers were spiked with respective target M. tb samples for testing. A limit of detection of 102 colony-forming unit per millilitre in 15 min was achieved, making early detection and differentiation of M. tb strains highly feasible in extreme POC settings. Our RT-RPA LOAD platform has also been successfully applied in the differentiation of MDR-TB from H37Ra, an attenuated TB strain. In summary, a quantitative RT-RPA on LOAD assay with a high level of sensitivity was developed as a foundation for further developments in medical bedside and POC diagnostics.


Subject(s)
Automation , Lab-On-A-Chip Devices , Mycobacterium tuberculosis/genetics , Nucleic Acid Amplification Techniques , Polymerase Chain Reaction , Tuberculosis, Multidrug-Resistant/genetics , Healthy Volunteers , Humans , Point-of-Care Testing , Time Factors
3.
Eye (Lond) ; 31(3): 475-480, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27858935

ABSTRACT

PurposeAutosomal-dominant optic atrophy (ADOA), often associated with mutations in the OPA1 gene (chromosome 3q28-q29) is rarely reported in Asia. Our aim was to identify and describe this condition in an Asian population in Singapore.Patients and methodsPreliminary cross-sectional study at the Singapore National Eye Centre, including patients with clinical suspicion of ADOA, who subsequently underwent genetic testing by direct sequencing of the OPA1 gene.ResultsAmong 12 patients (10 families) with clinically suspected ADOA, 7 patients (5 families) from 3 different ethnic origins (Chinese, Indian, and Malay) carried a heterozygous pathogenic variant in the OPA1 gene. The OPA1 mutations were located on exons 8, 9, 11, and 17: c.869G>A (p.Arg290Glu), c.892A>G (p.Ser298Gly), c.1140G>A (splicing mutation), and c.1669C>T (p.Arg557*), respectively. One splicing mutation (c.871-1G>A) was identified in intron 8. We also identified a novel mutation causing optic atrophy and deafness (c.892A>G (p.Ser298Gly)). Among the phenotypic features, colour pupillometry disclosed a dissociation between low vision and preserved pupillary light reflex in ADOA.ConclusionWe report the first cases of genetically confirmed OPA1-related ADOA from Singapore, including a novel mutation causing 'ADOA plus' syndrome. Further epidemiological studies are needed in order to determine the prevalence of ADOA in South-East Asia.


Subject(s)
GTP Phosphohydrolases/genetics , Genetic Predisposition to Disease , Mutation , Optic Atrophy, Autosomal Dominant/genetics , Adult , Aged , Asian People , Cross-Sectional Studies , DNA Mutational Analysis , Female , Humans , Male , Middle Aged , Optic Atrophy, Autosomal Dominant/ethnology , Singapore , Visual Acuity
4.
Biosens Bioelectron ; 93: 212-219, 2017 07 15.
Article in English | MEDLINE | ID: mdl-27660018

ABSTRACT

Sepsis by bacterial infection causes high mortality in patients in intensive care unit (ICU). Rapid identification of bacterial infection is essential to ensure early appropriate administration of antibiotics to save lives of patients, yet the present benchtop molecular diagnosis is time-consuming and labor-intensive, which limits the treatment efficiency especially when the number of samples to be tested is extensive. Therefore, we hereby report a microfluidic platform lab-on-a-disc (LOAD) to provide a sample-to-answer solution. Our LOAD customized design of microfluidic channels allows automation to mimic sequential analytical steps in benchtop environment. It relies on a simple but controllable centrifugation force for the actuation of samples and reagents. Our LOAD system performs three major functions, namely DNA extraction, isothermal DNA amplification and real-time signal detection, in a predefined sequence. The disc is self-contained for conducting sample heating with chemical lysis buffer and silica microbeads are employed for DNA extraction from clinical specimens. Molecular diagnosis of specific target bacteria DNA sequences is then performed using a real-time loop-mediated isothermal amplification (RT-LAMP) with SYTO-9 as the signal reporter. Our LOAD system capable of bacterial identification of Mycobacterium tuberculosis (TB) and Acinetobacter baumanii (Ab) with the detection limits 103cfu/mL TB in sputum and 102cfu/mL Ab in blood within 2h after sample loading. The reported LOAD based on an integrated approach should address the growing needs for rapid point-of-care medical diagnosis in ICU.


Subject(s)
Acinetobacter baumannii/isolation & purification , Biosensing Techniques , DNA, Bacterial/isolation & purification , Mycobacterium tuberculosis/isolation & purification , Sepsis/microbiology , Acinetobacter baumannii/pathogenicity , DNA, Bacterial/chemistry , Humans , Microfluidic Analytical Techniques , Mycobacterium tuberculosis/pathogenicity , Organic Chemicals/chemistry , Sepsis/diagnosis
5.
J Thromb Haemost ; 14(12): 2509-2523, 2016 12.
Article in English | MEDLINE | ID: mdl-27797450

ABSTRACT

Essentials Current antifibrinolytics - aminocaproic acid and tranexamic acid-can cause seizures or renal injury. KD1L17R -KT , aprotinin and tranexamic acid were tested in a modified mouse tail-amputation model. S2'-subsite variations between human and mouse factor XIa result in vastly different inhibition profiles. KD1L17R -KT reduces blood loss and D-dimer levels in mouse with unobserved seizures or renal injury. SUMMARY: Background Using tissue factor pathway inhibitor (TFPI)-2 Kunitz domain1 (KD1), we obtained a bifunctional antifibrinolytic molecule (KD1L17R -KT ) with C-terminal lysine (kringle domain binding) and P2'-residue arginine (improved specificity towards plasmin). KD1L17R -KT strongly inhibited human plasmin (hPm), with no inhibition of human kallikrein (hKLK) or factor XIa (hXIa). Furthermore, KD1L17R -KT reduced blood loss comparable to aprotinin in a mouse liver-laceration model of organ hemorrhage. However, effectiveness of these antifibrinolytic agents in a model of hemorrhage mimicking extremity trauma and their inhibition efficiencies for mouse enzymes (mPm, mKLK or mXIa) remain to be determined. Objective To determine potential differences in inhibition constants of various antifibrinolytic agents against mouse and human enzymes and test their effectiveness in a modified mouse tail-amputation hemorrhage model. Methods/Results Unexpectedly, mXIa was inhibited with ~ 17-fold increased affinity by aprotinin (Ki ~ 20 nm) and with measurable affinity for KD1L17R -KT (Ki ~ 3 µm); in contrast, KD1WT -VT inhibited hXIa or mXIa with similar affinity. Compared with hPm, mPm had ~ 3-fold reduced affinity, whereas species specificity for hKLK and mKLK was comparable for each inhibitor. S2'-subsite variations largely accounted for the observed differences. KD1L17R -KT and aprotinin were more effective than KD1WT -VT or tranexamic acid in inhibiting tPA-induced mouse plasma clot lysis. Further, KD1L17R -KT was more effective than KD1WT -VT and was comparable to aprotinin and tranexamic acid in reducing blood loss and D-dimer levels in the mouse tail-amputation model. Conclusions Inhibitor potencies differ between antifibrinolytic agents against human and mouse enzymes. KD1L17R -KT is effective in reducing blood loss in a tail-amputation model that mimics extremity injury.


Subject(s)
Factor XIa/genetics , Fibrinolysin/genetics , Glycoproteins/chemistry , Kallikreins/genetics , Animals , Antifibrinolytic Agents , Aprotinin/chemistry , Cattle , Fibrin Fibrinogen Degradation Products/chemistry , Fibrinolysis , Glycoproteins/genetics , Hemorrhage , Humans , Leucine/chemistry , Liver/metabolism , Mice , Models, Molecular , Mutation , Peptide Hydrolases/chemistry , Protein Domains , Seizures , Species Specificity , Tranexamic Acid/chemistry , Trypsin/chemistry
6.
Eur Ann Otorhinolaryngol Head Neck Dis ; 133 Suppl 1: S25-30, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27267231

ABSTRACT

OBJECTIVES: The Children Using Hearing Devices Quality of Life Questionnaire (CuHDQOL) is a new parent-administered hearing-specific questionnaire for children fitted with hearing devices. The aim of this study was to assess outcomes for hearing-impaired children in Singapore using this measure, as well as to examine its applicability for use in a clinical setting. MATERIALS AND METHODS: The CuHDQOL has 26 items, uses a recall period of 1 month, and is divided into three sections: parental perspectives and expectations (eight items), impact on the family (eight items) and hearing-related quality of life (QOL) of the child (10 items). Responses are made on a 5-point Likert scale, and transformed to a score from 0-100. Twenty-two parents of children with hearing aids and 14 parents of children with cochlear implants completed the CuHDQOL. RESULTS: The mean total CuHDQOL scores was 62/100 for the children using hearing aids and 53/100 for children with cochlear implants. Scores for the children using hearing aids were higher across all subscales, with a linear regression showing this to be significant for the parental perspectives and expectations subscale (B=-10.58, P=0.041). Analyses of Variance showed that both the 'Parent Perspective and Expectations' and the 'Hearing-related QOL' subscales were significantly higher than the 'Impact on Family' subscale for both groups (P≤0.003). CONCLUSIONS: The CuHDQOL was found to be a simple, efficient questionnaire that could easily be incorporated into clinical practice to provide a more holistic evaluation of a child's outcomes post intervention, and/or to monitor their progress over time.


Subject(s)
Cochlear Implants , Hearing Aids , Parents , Quality of Life , Child, Preschool , Hearing Loss/therapy , Humans , Infant , Linear Models , Singapore , Surveys and Questionnaires
7.
Oncogene ; 35(25): 3303-13, 2016 06 23.
Article in English | MEDLINE | ID: mdl-26455318

ABSTRACT

Despite abundant data supporting c-Src as a metastasis-promoting oncogene, activating mutations of c-Src are rare. This suggests that trans-interacting proteins may have a critical role in regulating c-Src activation. Here, we first report the discovery of Src homology 3 (SH3) domain-binding glutamic acid-rich-like protein (SH3BGRL), a novel c-Src activator in mice. Ectopic expression of murine SH3BGRL (mSH3BGRL) strongly promoted both tumor cell invasion and lung metastasis. Molecularly, mSH3BGRL specifically bound the inactive form of c-Src phosphorylated at Tyr527, promoting Tyr416 phosphorylation of c-Src and subsequent FAK-mediated activation of ERK and AKT signaling pathways. Targeting endogenous c-Src alone was sufficient to abolish mSH3BGRL-induced cancer metastasis in vivo. Unexpectedly, human SH3BGRL (hSH3BGRL) in turn suppressed tumorigenesis and metastasis in nature. We attempted site-specific reversion of hSH3BGRL amino-acid sequence to mSH3BGRL and found V108A substitution sufficient to restore SH3BGRL function as a c-Src activator and metastasis promoter. Notably, the somatic mutation R76C of hSH3BGRL can similarly act as hSH3BGRL-V108A and mSH3BGRL in tumorigenesis and metastasis. Our results uncover an evolutionarily controversial role of SH3BGRL in driving tumor metastasis through c-Src activation, and suggests that hSH3BGRL mutation status could be relevant to cancer diagnosis and therapy.


Subject(s)
Neoplasms/genetics , Oncogenes/genetics , Proteins/genetics , Tumor Suppressor Proteins/genetics , Amino Acid Sequence , Animals , Blotting, Western , CHO Cells , Cell Line, Tumor , Cell Movement/genetics , Cricetinae , Cricetulus , Humans , MCF-7 Cells , Mice, Nude , Mutation , Neoplasm Metastasis , Neoplasms/metabolism , Neoplasms/pathology , Protein Binding , Proteins/metabolism , Proto-Oncogene Proteins pp60(c-src)/genetics , Proto-Oncogene Proteins pp60(c-src)/metabolism , RNA Interference , Sequence Homology, Amino Acid , Signal Transduction/genetics , Transplantation, Heterologous
8.
Heredity (Edinb) ; 116(3): 295-303, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26696137

ABSTRACT

Owing to the reduction of population density and/or the environmental changes it induces, selective logging could affect the demography, reproductive biology and evolutionary potential of forest trees. This is particularly relevant in tropical forests where natural population densities can be low and isolated trees may be subject to outcross pollen limitation and/or produce low-quality selfed seeds that exhibit inbreeding depression. Comparing reproductive biology processes and genetic diversity of populations at different densities can provide indirect evidence of the potential impacts of logging. Here, we analysed patterns of genetic diversity, mating system and gene flow in three Central African populations of the self-compatible legume timber species Erythrophleum suaveolens with contrasting densities (0.11, 0.68 and 1.72 adults per ha). The comparison of inbreeding levels among cohorts suggests that selfing is detrimental as inbred individuals are eliminated between seedling and adult stages. Levels of genetic diversity, selfing rates (∼16%) and patterns of spatial genetic structure (Sp ∼0.006) were similar in all three populations. However, the extent of gene dispersal differed markedly among populations: the average distance of pollen dispersal increased with decreasing density (from 200 m in the high-density population to 1000 m in the low-density one). Overall, our results suggest that the reproductive biology and genetic diversity of the species are not affected by current logging practices. However, further investigations need to be conducted in low-density populations to evaluate (1) whether pollen limitation may reduce seed production and (2) the regeneration potential of the species.


Subject(s)
Fabaceae/genetics , Gene Flow , Genetic Variation , Genetics, Population , Pollination , Trees/genetics , Africa , Forestry , Inbreeding , Models, Genetic , Population Density , Rainforest
9.
Doc Ophthalmol ; 131(3): 189-96, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26471028

ABSTRACT

PURPOSE: To assess clinical value of visual electrophysiology in identifying causes of visual dysfunction in patients referred from neuro-ophthalmology clinics. METHODS: A review of 410 subjects (aged 0.3-88 years) referred for visual electrophysiology from neuro-ophthalmologists between 2009 and 2013 was performed. Subjects were divided into those with unexplained poor vision, visual field defects, visual symptoms or other reasons (e.g. monitoring for drug toxicity or known conditions). Subjects underwent pattern, full-field and multifocal electroretinography (ERG) and pattern visual evoked potential (VEP) tests. Flash and multifocal VEP were included where indicated. RESULTS: Most subjects referred for poor vision (n = 158) had electrophysiology findings suggestive of retinopathy (37 %) or post-retinal pathology (34 %). Those with poorer vision (worse than 6/24) were more likely to have abnormal recordings (86 vs. 62 %, p = 0.002). Among subjects with unexplained visual field defects (n = 102), findings of retinopathy, post-retinal pathology and normal recordings were noted in 31, 24 and 28 %, respectively. Most subjects with other visual symptoms (n = 97) had normal findings (69 %). The multifocal ERG was most sensitive for detecting retinopathy (96 %) and maculopathy (95 %), while pattern VEP was most sensitive for post-retinal pathology (94 %). An indeterminate result was noted in 9 %. CONCLUSION: Electrophysiology was effective in differentiating between retinopathy, post-retinal pathology and normality in 91 % of subjects. Pre-testing provisional diagnoses of retinopathy and post-retinal pathology were revised in 30 and 42 %, respectively, after electrophysiology. Appreciation of characteristics of each test, correlation with the clinical picture and interpretation of results in totality are required to localize the site of pathology.


Subject(s)
Electroretinography/methods , Evoked Potentials, Visual , Optic Disk/physiopathology , Optic Nerve Diseases/diagnosis , Retinal Diseases/diagnosis , Vision Disorders/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Electrophysiology , Female , Humans , Infant , Male , Middle Aged , Optic Nerve Diseases/physiopathology , Retinal Diseases/physiopathology , Retinal Ganglion Cells/physiology , Retrospective Studies , Vision Disorders/physiopathology , Visual Fields/physiology
10.
J Anim Sci ; 92(11): 4964-71, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25349345

ABSTRACT

Fructan supplementation of a commercially available canned cat food was evaluated using senior (≥ 9 yr) cats to assess nitrogen (N) partitioning in excreta and stool metabolite and microbiota concentrations. Oligofructose (OF) or SynergyC (OF+IN) were added to the diet individually at 1% (dry weight basis). Cats were acclimated to the control diet for 7 d and then were randomly assigned to 1 of 3 treatment groups for 21 d (n = 6). Feces and urine were collected on d 22 through 28. No differences were observed in food intake; fecal output, DM percentage, score, pH, or short- or branched-chain fatty acids, fecal and urinary ammonia output, urinary felinine concentrations, or N retention. Supplemental OF+IN tended to decrease N digestibility (P = 0.102) and Bifidobacteria spp. (P = 0.073) and decrease fecal indole (P < 0.05), tyramine (P < 0.05), and Escherichia coli (P < 0.05) concentrations. Both fructan-supplemented treatments decreased (P < 0.05) fecal histamine concentrations. The tendency to a lower apparent N digestibility was likely due to increased colonic microbial protein synthesis of fructan-supplemented cats. Fructan supplementation may benefit senior cats as it modulates stool odor-forming compounds and decreases some protein catabolites and pathogenic gut microbiota concentrations without affecting N retention.


Subject(s)
Cats/metabolism , Feces/microbiology , Fructans/pharmacology , Microbiota , Nitrogen/metabolism , Ammonia/metabolism , Animals , Bifidobacterium/isolation & purification , Dietary Supplements , Eating/drug effects , Eating/physiology , Escherichia coli/isolation & purification , Feces/chemistry , Female , Fructans/administration & dosage , Intestinal Elimination/drug effects , Intestinal Elimination/physiology , Male , Nitrogen/analysis
11.
Sci Rep ; 3: 2874, 2013 Oct 07.
Article in English | MEDLINE | ID: mdl-24096686

ABSTRACT

We illustrate the important trade-off between far-field scattering effects, which have the potential to provide increased optical path length over broad bands, and parasitic absorption due to the excitation of localized surface plasmon resonances in metal nanoparticle arrays. Via detailed comparison of photocurrent enhancements given by Au, Ag and Al nanostructures on thin-film GaAs devices we reveal that parasitic losses can be mitigated through a careful choice of scattering medium. Absorption at the plasmon resonance in Au and Ag structures occurs in the visible spectrum, impairing device performance. In contrast, exploiting Al nanoparticle arrays results in a blue shift of the resonance, enabling the first demonstration of truly broadband plasmon enhanced photocurrent and a 22% integrated efficiency enhancement.

12.
Gene Ther ; 19(8): 872-6, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22551777

ABSTRACT

Patients with X-linked severe combined immunodeficiency (SCID-X1) were successfully cured following gene therapy with a gamma-retroviral vector (gRV) expressing the common gamma chain of the interleukin-2 receptor (IL2RG). However, 5 of 20 patients developed leukemia from activation of cellular proto-oncogenes by viral enhancers in the long-terminal repeats (LTR) of the integrated vector. These events prompted the design of a gRV vector with self-inactivating (SIN) LTRs to enhance vector safety. Herein we report on the production of a clinical-grade SIN IL2RG gRV pseudotyped with the Gibbon Ape Leukemia Virus envelope for a new gene therapy trial for SCID-X1, and highlight variables that were found to be critical for transfection-based large-scale SIN gRV production. Successful clinical production required careful selection of culture medium without pre-added glutamine, reduced exposure of packaging cells to cell-dissociation enzyme, and presence of cations in wash buffer. The clinical vector was high titer; transduced 68-70% normal human CD34(+) cells, as determined by colony-forming unit assays and by xenotransplantation in immunodeficient NOD.CB17-Prkdc(scid)/J (nonobese diabetic/severe combined immunodeficiency (NOD/SCID)) and NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ (NOD/SCID gamma (NSG))) mice; and resulted in the production of T cells in vitro from human SCID-X1 CD34(+) cells. The vector was certified and released for the treatment of SCID-X1 in a multi-center international phase I/II trial.


Subject(s)
Genetic Vectors , Interleukin Receptor Common gamma Subunit/genetics , Retroviridae/genetics , X-Linked Combined Immunodeficiency Diseases/therapy , Animals , Gene Transfer Techniques , Humans , Leukemia Virus, Gibbon Ape/genetics , Mice , Mice, Inbred NOD , Mice, SCID , Terminal Repeat Sequences , Transduction, Genetic
13.
Anal Chem ; 84(10): 4383-95, 2012 May 15.
Article in English | MEDLINE | ID: mdl-22509742

ABSTRACT

Top-down mass spectrometry has been used to investigate structural diversity within some abundant salivary protein families. In this study, we report the identification of two isoforms of protein II-2 which differed in mass by less than 1 Da, the determination of a sequence for protein IB8a that was best satisfied by including a mutation and a covalent modification in the C-terminal part, and the assignment of a sequence of a previously unreported protein of mass 10433 Da. The final characterization of Peptide P-J was achieved, and the discovery of a truncated form of this peptide was reported. The first sequence assignment was done at low resolution using a hybrid quadrupole time-of-flight instrument to quickly identify and characterize proteins, and data acquisition was switched to Fourier-transform ion cyclotron resonance (FTICR) for proteins that required additional sequence coverage and certainty of assignment. High-resolution and high mass accuracy mass spectrometry on a FTICR-mass spectrometry (MS) instrument combined with electron-capture dissociation (ECD) provided the most informative data sets, with the more frequent presence of "unique" ions that unambiguously define the primary structure. A mixture of predictable and unusual post-translational modifications in the protein sequence precluded the use of shotgun-annotated databases at this stage, requiring manual iterations of sequence refinement in many cases. This led us to propose guidelines for an iterative processing workflow of MS and MSMS data sets that allow researchers to completely assign the identity and the structure of a protein.


Subject(s)
Proteins/chemistry , Proteome , Saliva/metabolism , Spectrometry, Mass, Electrospray Ionization , Amino Acid Sequence , Chromatography, High Pressure Liquid , Histatins/chemistry , Humans , Molecular Sequence Data
14.
Arch Toxicol ; 86(5): 741-52, 2012 May.
Article in English | MEDLINE | ID: mdl-22349056

ABSTRACT

Polyphyllin D (PD) is a potent anticancer agent isolated from a traditional medicinal herb Paris polyphylla that has been used in China for many years to treat cancer. PD is not a substrate of p-glycoprotein, and it can bypass the multi-drug resistance in cancer cell line R-HepG2. However, the effect of PD on the induction of cell death in human erythrocytes remains unknown. Given that PD is a small molecule that can depolarize the mitochondrial membrane potential and release apoptosis-inducing factor (AIF) in isolated mitochondria, we hypothesized that the apoptogenic effect of PD in human erythrocytes devoid of mitochondria would be minimal. This study therefore tried to evaluate the in vitro effect of PD on hemolysis and apoptosis in human erythrocytes. Apoptosis in human red blood cells (RBCs), also known as eryptosis or erythroptosis, after PD treatment was determined by flow cytometry and confocal microscopy for the phosphatidyl-serine externalization and other apoptosis feature events. False to our prediction, PD caused hemolysis and eryptosis/erythroptosis in human RBCs. Mechanistically, elevation in the cytosolic Ca²âº ion level seems to be a key but not the only mediator in the PD-mediated eryptosis/erythroptosis because depletion of the external Ca²âº could not eliminate the PD effect. Also, PD was able to permeabilize the membrane of RBC ghosts in a way similar to digitonin. Taken together, we report here for the first time the toxicity of PD in human RBCs as well as its underlying mechanism for the hemolysis and eryptosis/erythroptosis.


Subject(s)
Apoptosis/drug effects , Cell Membrane Permeability/drug effects , Diosgenin/analogs & derivatives , Erythrocytes/drug effects , Calcium/metabolism , Caspase 3/metabolism , Cell Size/drug effects , Cells, Cultured , Cytosol/drug effects , Cytosol/metabolism , Diosgenin/pharmacology , Diosgenin/toxicity , Erythrocytes/metabolism , Erythrocytes/pathology , Humans , Mitochondrial Membranes/drug effects , Saponins
15.
Gene Ther ; 19(3): 246-54, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21753795

ABSTRACT

The need for γ-retroviral (gRV) vectors with a self-inactivating (SIN) design for clinical application has prompted a shift in methodology of vector manufacturing from the traditional use of stable producer lines to transient transfection-based techniques. Herein, we set out to define and optimize a scalable manufacturing process for the production of gRV vectors using transfection in a closed-system bioreactor in compliance with current good manufacturing practices (cGMP). The process was based on transient transfection of 293T cells on Fibra-Cel disks in the Wave Bioreactor. Cells were harvested from tissue culture flasks and transferred to the bioreactor containing Fibra-Cel in the presence of vector plasmid, packaging plasmids and calcium-phosphate in Dulbecco's modified Eagle's medium and 10% fetal bovine serum. Virus supernatant was harvested at 10-14 h intervals. Using optimized procedures, a total of five ecotropic cGMP-grade gRV vectors were produced (9 liters each) with titers up to 3.6 × 10(7) infectious units per milliliter on 3T3 cells. One GMP preparation of vector-like particles was also produced. These results describe an optimized process for the generation of SIN viral vectors by transfection using a disposable platform that allows for the generation of clinical-grade viral vectors without the need for cleaning validation in a cost-effective manner.


Subject(s)
Bioreactors , Gammaretrovirus/genetics , Genetic Vectors/isolation & purification , Genetic Vectors/standards , Transfection/methods , Animals , Batch Cell Culture Techniques/methods , Batch Cell Culture Techniques/standards , Biotechnology , Cell Line , Gammaretrovirus/isolation & purification , Humans , Mice , Quality Control
16.
J Dent Res ; 89(10): 1016-23, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20739693

ABSTRACT

The protein compositions, or the proteomes, found in human salivary and plasma fluids are compared. From recent experimental work by many laboratories, a catalogue of 2290 proteins found in whole saliva has been compiled. This list of salivary proteins is compared with the 2698 proteins found in plasma. Approximately 27% of the whole-saliva proteins are found in plasma. However, despite this apparent low degree of overlap, the distribution found across Gene Ontological categories, such as molecular function, biological processes, and cellular components, shows significant similarities. Moreover, nearly 40% of the proteins that have been suggested to be candidate markers for diseases such as cancer, cardiovascular disease, and stroke can be found in whole saliva. These comparisons and correlations should encourage researchers to consider the use of saliva to discover new protein markers of disease and as a diagnostic non-proximal fluid to detect early signs of disease throughout the body.


Subject(s)
Blood Proteins/analysis , Proteome/analysis , Salivary Proteins and Peptides/analysis , Biomarkers/analysis , Biomarkers, Tumor/analysis , Cardiovascular Diseases/metabolism , Early Diagnosis , Humans , Plasma , Stroke/metabolism
17.
Neurocrit Care ; 12(3): 324-36, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20225002

ABSTRACT

BACKGROUND: To examine if the metabolic distress after traumatic brain injury (TBI) is associated with a unique proteome. METHODS: Patients with severe TBI prospectively underwent cerebral microdialysis for the initial 96 h after injury. Hourly sampling of metabolism was performed and patients were categorized as having normal or abnormal metabolism as evidenced by the lactate/pyruvate ratio (LPR) threshold of 40. The microdialysate was frozen for proteomic batch processing retrospectively. We employed two different routes of proteomic techniques utilizing mass spectrometry (MS) and categorized as diagnostic and biomarker identification approaches. The diagnostic approach was aimed at finding a signature of MS peaks which can differentiate these two groups. We did this by enriching for intact peptides followed by MALDI-MS analysis. For the biomarker identification approach, we applied classical bottom-up (trypsin digestion followed by LC-MS/MS) proteomic methodologies. RESULTS: Five patients were studied, 3 of whom had abnormal metabolism and 2 who had normal metabolism. By comparison, the abnormal group had higher LPR (1609 +/- 3691 vs. 15.5 +/- 6.8, P < 0.001), higher glutamate (157 +/- 84 vs. 1.8 +/- 1.4 microM, P < 0.001), and lower glucose (0.27 +/- 0.35 vs. 1.8 +/- 1.1 mmol/l, P < 0.001). The abnormal group demonstrated 13 unique proteins as compared with the normal group in the microdialysate. These proteins consisted of cytoarchitectural proteins, as well as blood breakdown proteins, and a few mitochondrial proteins. A unique as yet to be characterized peptide was found at m/z (mass/charge) 4733.5, which may represent a novel biomarker of metabolic distress. CONCLUSION: Metabolic distress after TBI is associated with a differential proteome that indicates cellular destruction during the acute phase of illness. This suggests that metabolic distress has immediate cellular consequences after TBI.


Subject(s)
Brain Injuries/physiopathology , Brain/physiopathology , Energy Metabolism/physiology , Microdialysis/instrumentation , Monitoring, Physiologic/instrumentation , Proteomics , Signal Processing, Computer-Assisted/instrumentation , Blood Glucose/metabolism , Brain Ischemia/diagnosis , Brain Ischemia/physiopathology , Cerebral Hemorrhage, Traumatic/diagnosis , Cerebral Hemorrhage, Traumatic/physiopathology , Extracellular Fluid/physiology , Follow-Up Studies , Frontal Lobe/physiopathology , Glasgow Coma Scale , Humans , Hypoglycemia/diagnosis , Hypoglycemia/physiopathology , Intracranial Pressure/physiology , Lactic Acid/blood , Magnetic Resonance Imaging , Pyruvic Acid/blood , Reference Values , Tandem Mass Spectrometry/instrumentation , Temporal Lobe/physiopathology , Tomography, X-Ray Computed
18.
Br J Nutr ; 101 Suppl 1: S1-45, 2009 May.
Article in English | MEDLINE | ID: mdl-19586558

ABSTRACT

Inflammation is a stereotypical physiological response to infections and tissue injury; it initiates pathogen killing as well as tissue repair processes and helps to restore homeostasis at infected or damaged sites. Acute inflammatory reactions are usually self-limiting and resolve rapidly, due to the involvement of negative feedback mechanisms. Thus, regulated inflammatory responses are essential to remain healthy and maintain homeostasis. However, inflammatory responses that fail to regulate themselves can become chronic and contribute to the perpetuation and progression of disease. Characteristics typical of chronic inflammatory responses underlying the pathophysiology of several disorders include loss of barrier function, responsiveness to a normally benign stimulus, infiltration of inflammatory cells into compartments where they are not normally found in such high numbers, and overproduction of oxidants, cytokines, chemokines, eicosanoids and matrix metalloproteinases. The levels of these mediators amplify the inflammatory response, are destructive and contribute to the clinical symptoms. Various dietary components including long chain omega-3 fatty acids, antioxidant vitamins, plant flavonoids, prebiotics and probiotics have the potential to modulate predisposition to chronic inflammatory conditions and may have a role in their therapy. These components act through a variety of mechanisms including decreasing inflammatory mediator production through effects on cell signaling and gene expression (omega-3 fatty acids, vitamin E, plant flavonoids), reducing the production of damaging oxidants (vitamin E and other antioxidants), and promoting gut barrier function and anti-inflammatory responses (prebiotics and probiotics). However, in general really strong evidence of benefit to human health through anti-inflammatory actions is lacking for most of these dietary components. Thus, further studies addressing efficacy in humans linked to studies providing greater understanding of the mechanisms of action involved are required.


Subject(s)
Inflammation/physiopathology , Nutritional Physiological Phenomena/physiology , Arthritis, Rheumatoid/diet therapy , Arthritis, Rheumatoid/physiopathology , Cardiovascular Diseases/diet therapy , Cardiovascular Diseases/physiopathology , Celiac Disease/diet therapy , Celiac Disease/physiopathology , Humans , Inflammation/diet therapy , Inflammatory Bowel Diseases/diet therapy , Inflammatory Bowel Diseases/physiopathology , Obesity/diet therapy , Obesity/physiopathology , Respiratory Hypersensitivity/diet therapy , Respiratory Hypersensitivity/physiopathology , Skin Diseases/diet therapy , Skin Diseases/physiopathology
19.
J Appl Microbiol ; 106(3): 932-40, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19191975

ABSTRACT

AIMS: To search for nondigestible but fermentable (NDF) carbohydrates and prebiotics with a potency to promote the growth of selected bacteria in vitro. METHODS AND RESULTS: The growth of three reference bacteria strains Bacillus subtilis LMG 7135(T), Carnobacterium piscicola LMG 9839, Lactobacillus plantarum LMG 9211 and one candidate probiotic bacteria Lactobacillus delbrueckii subsp. lactis was investigated over a minimum period of 48 h in the presence of beta-glucan, xylo-oligosaccharide, arabinoxylo-oligosaccharide, inulin, oligofructose and glucose. Besides the capability to grow on inulin and oligofructose containing media, a distinct high growth in beta-glucan based substrates and a low growth in (arabino)xylooligosaccharide containing media were evident for most bacteria tested. With the exception of B. subtilis and L. plantarum, other bacteria grew equally well or even better on different substrates than on glucose. The fermentation of studied carbohydrates by these micro-organisms was dominated by the production of acetic acid as the main short chain fatty acid. CONCLUSIONS: Selected bacteria are able to ferment and grow on NDF and prebiotic carbohydrates but in a substrate dependent manner. SIGNIFICANCE AND IMPACT OF THE STUDY: This study delivers a first screening of which NDF or prebiotic carbohydrates are the most promising for aquaculture feed supplementations.


Subject(s)
Bacteria/growth & development , Carbohydrate Metabolism , Prebiotics , Probiotics , Acetic Acid/metabolism , Animals , Bacillus subtilis/growth & development , Bacteria/metabolism , Bacteriological Techniques , Carnobacterium/growth & development , Colony Count, Microbial , Culture Media , Fishes/microbiology , Glucose/metabolism , Inulin/metabolism , Lactobacillus/growth & development , Oligosaccharides/metabolism , beta-Glucans/metabolism
20.
J Biomed Mater Res A ; 84(4): 980-7, 2008 Mar 15.
Article in English | MEDLINE | ID: mdl-17647238

ABSTRACT

The ability to undergo predictable and controlled degradation allows biopolymers to release prescribed dosages of drugs locally over a sustained period. However, the bulk or homogeneous degradation of some of these polymers like poly(L-lactide) (PLLA) and poly(lactide-co-glycolide) (PLGA) work against a better controlled release of the drugs. Inducing the polymers to undergo surface erosion or layer-by-layer degradation could provide a better process of controlled drug release from the polymers. This study has demonstrated that surface erosion degradation of PLGA is possible with the use of a multilayer film system, with PPdlLGA [plasticized poly(D,L-lactide-co-glycolide) (PdlLGA)] as the surface layers and poly(L-lactide-co-glycolide) as the center layer. The use of the more hydrophilic PPdlLGA as the surface layer resulted in a faster degradation of the surface layers compared to the center layer, thus giving a surface erosion degradation effect. The rate of surface degradation could also be controlled with electron beam (e-beam) radiation, where e-beam irradiation was shown to alter the degradation time and onset of polymer mass loss. It was also shown that the more highly irradiated PPdlLGA surface layers had an earlier onset of mass loss, which resulted in a faster reduction in overall film thickness. The ability to control the rate of film thickness reduction with different radiation dose promises a better controlled release of drugs from this multilayer PLGA film system.


Subject(s)
Biocompatible Materials/chemistry , Biotechnology/methods , Drug Carriers , Drug Delivery Systems , Electrons , Hydrolysis , Lactic Acid/chemistry , Microscopy, Electron, Scanning , Microspheres , Molecular Weight , Oxygen/chemistry , Polyglactin 910/chemistry , Polyglycolic Acid/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer , Polymers/chemistry , Surface Properties , Temperature
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