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1.
Nature ; 629(8010): 201-210, 2024 May.
Article in English | MEDLINE | ID: mdl-38600376

ABSTRACT

Chimeric antigen receptor (CAR) T cell therapy has transformed the treatment of haematological malignancies such as acute lymphoblastic leukaemia, B cell lymphoma and multiple myeloma1-4, but the efficacy of CAR T cell therapy in solid tumours has been limited5. This is owing to a number of factors, including the immunosuppressive tumour microenvironment that gives rise to poorly persisting and metabolically dysfunctional T cells. Analysis of anti-CD19 CAR T cells used clinically has shown that positive treatment outcomes are associated with a more 'stem-like' phenotype and increased mitochondrial mass6-8. We therefore sought to identify transcription factors that could enhance CAR T cell fitness and efficacy against solid tumours. Here we show that overexpression of FOXO1 promotes a stem-like phenotype in CAR T cells derived from either healthy human donors or patients, which correlates with improved mitochondrial fitness, persistence and therapeutic efficacy in vivo. This work thus reveals an engineering approach to genetically enforce a favourable metabolic phenotype that has high translational potential to improve the efficacy of CAR T cells against solid tumours.


Subject(s)
Forkhead Box Protein O1 , Immunotherapy, Adoptive , Neoplasms , Receptors, Chimeric Antigen , Stem Cells , T-Lymphocytes , Humans , Mice , Cell Line, Tumor , Forkhead Box Protein O1/metabolism , Forkhead Box Protein O1/genetics , Mitochondria/metabolism , Phenotype , Receptors, Chimeric Antigen/immunology , Receptors, Chimeric Antigen/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/cytology , Tumor Microenvironment/immunology , Stem Cells/cytology , Stem Cells/immunology , Stem Cells/metabolism , Neoplasms/immunology , Neoplasms/pathology , Neoplasms/therapy
2.
Cancer Epidemiol ; 79: 102184, 2022 08.
Article in English | MEDLINE | ID: mdl-35580366

ABSTRACT

BACKGROUND: This is the first evaluation study to assess the demographic characteristics of the colorectal cancer (CRC) cases detected in the prevalent round of the population-based Colorectal Cancer Screening Programme (CRCSP) in Hong Kong and to explore the effectiveness of the programme on the stage distribution of CRC. METHODS: This study covered the period between 28 September 2016 and 31 December 2018. Information on CRC diagnosis, age and stage at diagnosis were retrieved and reviewed by the Hong Kong Cancer Registry (HKCaR). The CRC detection rate among CRCSP-screened participants and incidence rate among the Hong Kong general population were calculated respectively. The odds ratio (OR) was calculated to measure the strength of association and quantify the effect of CRCSP on stage shift between CRCSP-detected CRC cases and an age-matched cohort of CRC cases diagnosed outside the programme. RESULTS: The CRC detection rate among participants of the CRCSP during the study period was 736.0/100,000, whereas the overall CRC incidence rate among general population of similar age groups was 393.7/100,000. For all ages and both sexes, the OR of stage I CRCSP-detected CRC compared to the CRC from the age-matched cohort was 3.91 (95%CI=3.41-4.48) and the OR dropped to 0.54 (95%CI=0.41-0.70) at stage IV. Meanwhile, the overall OR of CRCSP-detected CRC compared to CRC from the age-matched cohort dropped from 2.24 (95%CI=1.97-2.56) to 1.62 (95%CI=1.40-1.87) with increasing age. CONCLUSION: The present study has demonstrated the initial impact of the CRCSP on shifting the stage at diagnosis towards earlier stage. The benefit of stage-shift was similar for all ages from 60 to 77 in both sexes and seems to increase with younger age. Given the stage-dependent survival outcomes, this stage-shift could lead to a reduction in CRC-associated mortality in Hong Kong in future.


Subject(s)
Colorectal Neoplasms , Early Detection of Cancer , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/prevention & control , Female , Humans , Incidence , Male , Mass Screening , Registries
3.
Int J Chron Obstruct Pulmon Dis ; 15: 2015-2024, 2020.
Article in English | MEDLINE | ID: mdl-32904701

ABSTRACT

Background: Oxidative stress (OS) has been implicated in the development of pulmonary hypertension (PH) and ventricular hypertrophy. Xanthine oxidase is a well-recognised source of reactive oxygen species, which lead to OS. The aim of this proof of concept study was to assess whether allopurinol (xanthine oxidase inhibitor) would reduce right ventricular mass (RVM) in patients with PH-associated chronic lung disease (PH-CLD). Methods: We conducted a randomised, double-blind, parallel-group, placebo-controlled trial in patients with PH-CLD (93% COPD, 7% IPF) who were randomly assigned to receive allopurinol or placebo for 12 months. The primary outcome was the mean change in RVM, as assessed by cardiac magnetic resonance imaging (CMRI). Secondary outcomes included quality of life (QOL), spirometry and six-minute walk test (6MWT). Results: Seventy-one patients were recruited: mean age 71 years, mean pulmonary arterial pressure 30 mm Hg, FEV1 60% and resting SpO2 96%. After 12 months, there was no significant difference in the change in RVM from baseline (allopurinol 1.85g vs placebo 0.97g with mean difference 0.88g, CI -4.77 to 3.01, p =0.7). There were also no significant changes in other cardiac parameters measured on MRI, in QOL, spirometry and 6MWT. Subgroup analysis showed that allopurinol significantly reduced RVM compared to placebo with -6.16g vs 0.75g and mean difference 6.92g (CI 1.14 to 12.69, p = 0.02) in COPD patients with more severe airflow limitation. Conclusion: Allopurinol had no overall impact on patients with PH-CLD but had potential benefit in COPD patients with more severe airflow limitation.


Subject(s)
Hypertension, Pulmonary , Pulmonary Disease, Chronic Obstructive , Aged , Allopurinol/adverse effects , Double-Blind Method , Humans , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/drug therapy , Hypertension, Pulmonary/etiology , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/drug therapy , Quality of Life , Walk Test
5.
J Lipid Res ; 60(1): 85-97, 2019 01.
Article in English | MEDLINE | ID: mdl-30416103

ABSTRACT

Bile acid imbalance causes progressive familial intrahepatic cholestasis type 2 (PFIC2) or type 3 (PFIC3), severe liver diseases associated with genetic defects in the biliary bile acid transporter bile salt export pump (BSEP; ABCB11) or phosphatidylcholine transporter multidrug resistance protein 3 (MDR3; ABCB4), respectively. Mdr2-/- mice (a PFIC3 model) develop progressive cholangitis, ductular proliferation, periportal fibrosis, and hepatocellular carcinoma (HCC) because the nonmicelle-bound bile acids in the bile of these mice are toxic. We asked whether the highly hydrophilic bile acids generated by Bsep-/- mice could protect Mdr2-/- mice from progressive liver damage. We generated double-KO (DKO: Bsep-/- and Mdr2-/- ) mice. Their bile acid composition resembles that of Bsep-/- mice, with increased hydrophilic muricholic acids, tetrahydroxylated bile acids (THBAs), and reduced hydrophobic cholic acid. These mice lack the liver pathology of their Mdr2-/- littermates. The livers of DKO mice have gene expression profiles very similar to Bsep-/- mice, with 4,410 of 6,134 gene expression changes associated with the Mdr2-/- mutation being suppressed. Feeding with THBAs partially alleviates liver damage in the Mdr2-/- mice. Hydrophilic changes to biliary bile acid composition, including introduction of THBA, can prevent the progressive liver pathology associated with the Mdr2-/- (PFIC3) mutation.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B/deficiency , Bile Acids and Salts/pharmacology , Biliary Tract/metabolism , Cytoprotection/drug effects , Hydrophobic and Hydrophilic Interactions , Liver/injuries , Phospholipids/metabolism , ATP Binding Cassette Transporter, Subfamily B/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 11/deficiency , ATP Binding Cassette Transporter, Subfamily B, Member 11/genetics , Animals , Bile Acids and Salts/chemistry , Biliary Tract/drug effects , Gene Knockout Techniques , Hydroxylation , Liver/cytology , Liver/drug effects , Liver/metabolism , Male , Mice , Mutation , ATP-Binding Cassette Sub-Family B Member 4
6.
ACS Chem Biol ; 9(10): 2412-20, 2014 Oct 17.
Article in English | MEDLINE | ID: mdl-25101481

ABSTRACT

Because RNA lacks strong intrinsic fluorescence, it has proven challenging to track RNA molecules in real time. To address this problem and to allow the purification of fluorescently tagged RNA complexes, we have selected a high affinity RNA aptamer called RNA Mango. This aptamer binds a series of thiazole orange (fluorophore) derivatives with nanomolar affinity, while increasing fluorophore fluorescence by up to 1,100-fold. Visualization of RNA Mango by single-molecule fluorescence microscopy, together with injection and imaging of RNA Mango/fluorophore complex in C. elegans gonads demonstrates the potential for live-cell RNA imaging with this system. By inserting RNA Mango into a stem loop of the bacterial 6S RNA and biotinylating the fluorophore, we demonstrate that the aptamer can be used to simultaneously fluorescently label and purify biologically important RNAs. The high affinity and fluorescent properties of RNA Mango are therefore expected to simplify the study of RNA complexes.


Subject(s)
Aptamers, Nucleotide/metabolism , Caenorhabditis elegans/genetics , Fluorescent Dyes/chemistry , Microscopy, Fluorescence , RNA, Bacterial/chemistry , RNA, Untranslated/chemistry , RNA/isolation & purification , RNA/metabolism , Animals , Aptamers, Nucleotide/chemistry , Benzothiazoles/chemistry , Biotin/metabolism , Caenorhabditis elegans/metabolism , Gonads/metabolism , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/metabolism , Mangifera/chemistry , Quinolines/chemistry , RNA/chemistry , RNA, Bacterial/metabolism , RNA, Untranslated/metabolism , Spinacia oleracea/chemistry
7.
Cancer Res ; 74(9): 2412-21, 2014 May 01.
Article in English | MEDLINE | ID: mdl-24556719

ABSTRACT

Tumor-induced immunosuppression remains one of the major obstacles to many potentially effective cancer therapies and vaccines. Host interleukin (IL)-23 suppresses the immune response during tumor initiation, growth, and metastases, and neutralization of IL-23 causes IL-12-dependent antitumor effects. Here, we report that combining agonistic anti-CD40 monoclonal antibodies (mAb) to drive IL-12 production and anti-IL-23 mAbs to counter the tumor promoting effects of IL-23 has greater antitumor activity than either agent alone. This increased antitumor efficacy was observed in several experimental and spontaneous lung metastases models as well as in models of de novo carcinogenesis. The combination effects were dependent on host IL-12, perforin, IFN-γ, natural killer, and/or T cells and independent of host B cells and IFN-αß sensitivity. Interestingly, in the experimental lung metastases tumor models, we observed that intracellular IL-23 production was specifically restricted to MHC-II(hi)CD11c(+)CD11b(+) cells. Furthermore, an increase in proportion of these IL-23-producing cells was detected only in tumor models where IL-23 neutralization was therapeutic. Overall, these data suggest the clinical potential of using anti-CD40 (push) and anti-IL-23 mAbs (pull) to tip the IL-12/23 balance in established tumors.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , CD40 Antigens/immunology , Interleukin-23/immunology , Lung Neoplasms/drug therapy , Melanoma, Experimental/drug therapy , Animals , Antibodies, Monoclonal/administration & dosage , Antineoplastic Agents/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , CD40 Antigens/metabolism , Cell Line, Tumor , Drug Screening Assays, Antitumor , Female , Fibrosarcoma/drug therapy , Interleukin-12/metabolism , Interleukin-23/metabolism , Lung Neoplasms/secondary , Male , Melanoma, Experimental/pathology , Methylcholanthrene , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Neoplasm Transplantation , Pore Forming Cytotoxic Proteins/metabolism
8.
Appl Opt ; 49(9): 1539-48, 2010 Mar 20.
Article in English | MEDLINE | ID: mdl-20300148

ABSTRACT

By using the least-squares fitting approach, the calibration procedure for fringe projection profilometry becomes more flexible and easier, since neither the measurement of system geometric parameters nor precise control of plane moving is required. With consideration of camera lens distortion, we propose a modified least-squares calibration method for fringe projection profilometry. In this method, camera lens distortion is involved in the mathematical description of the system for least-squares fitting to reduce its influence. Both simulation and experimental results are shown to verify the validity and ease of use of this modified calibration method.

9.
J Endod ; 35(3): 393-6, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19249602

ABSTRACT

This study evaluated in vitro effectiveness of 17% EDTA with and without ultrasonics on smear layer removal. One hundred and five extracted premolars randomly divided into seven groups were instrumented with different final irrigating protocols: group A (Sal3US), saline for 3 minutes with ultrasonics; groups B (Na3) and C (Na3US), 1% sodium hypochlorite for 3 minutes without and with ultrasonics, respectively; groups D (ED3) and E (ED3US), 17% EDTA for 3 minutes without and with ultrasonics, respectively; and groups F (ED1) and G (ED1US), 17% EDTA for 1 minute without and with ultrasonics, respectively. Specimens were examined under scanning electron microscope and scored for smear layer and debris removal. Statistical analysis showed that groups with EDTA and ultrasonic irrigation, groups E (ED3US) and G (ED1US), had significantly more specimens with complete smear layer and debris removal. There was no significant difference between groups E (ED3US) and G (ED1US). A 1-minute application of combined use of EDTA and ultrasonics is efficient for smear layer and debris removal in the apical region of the root canal.


Subject(s)
Edetic Acid , Root Canal Irrigants , Root Canal Preparation/methods , Smear Layer , Bicuspid , Chelating Agents , Humans , Sodium Hypochlorite , Tooth Apex , Ultrasonic Therapy/instrumentation
10.
J Food Prot ; 64(8): 1220-5, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11510664

ABSTRACT

Fusarium graminearum, Fusarium culmorum, and Fusarium avenaceum, isolated from Fusarium-damaged wheat harvested in western Canada, were cultured and evaluated for mycotoxin production. Extracts of the culture media were assayed for trichothecenes by gas chromatography-mass spectrometry and for moniliformin by liquid chromatography. Deoxynivalenol (DON) was found in 28 of 42 isolates of F. graminearum and 42 of 42 isolates of F. culmorum at levels ranging from 0.5 to 25.0 microg/g. 15-AcetylDON was found in 28 of 42 isolates of F. graminearum at levels ranging from 1.0 to 7.1 microg/g. 3-AcetylDON was found in 41 of 42 isolates of F. culmorum at levels ranging from 0.8 to 13.0 microg/g. Several other trichothecenes were assayed but not detected in the culture medium. Moniliformin was present in 40 of 42 isolates of F. avenaceum at levels ranging from 1.3 to 138.1 microg/g, but was not present in any of the isolates of F. graminearum or F. culmorum.


Subject(s)
Cyclobutanes/metabolism , Food Contamination , Fusarium/metabolism , Trichothecenes/biosynthesis , Triticum/microbiology , Chromatography, Liquid , Cyclobutanes/analysis , Food Microbiology , Fusarium/pathogenicity , Gas Chromatography-Mass Spectrometry , Trichothecenes/analysis , Trichothecenes/toxicity
11.
IEEE Trans Neural Syst Rehabil Eng ; 9(1): 31-41, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11482361

ABSTRACT

In the clinical setting, parkinsonian rigidity is assessed using subjective rating scales such as that of the Unified Parkinson's Disease Rating System (UPDRS). However, such scales are susceptible to problems of sensitivity and reliability. Here, we evaluate the reliability and validity of a device designed to quantify parkinsonian rigidity at the elbow and the wrist. The method essentially quantifies the clinical examination and employs small sensors to monitor forces and angular displacements imposed by the clinician onto the limb segment distal to the joint being evaluated. Force and displacement data are used to calculate elastic and viscous stiffnesses and their vectorial sum, mechanical impedance. Interexaminer agreement of measures of mechanical impedance in subjects with Parkinson's disease was comparable to that of clinical UPDRS scores. Examiners tended to overrate rigidity on the UPDRS scale during reinforcement manoeuvres. Mechanical impedance was nonlinearly related to UPDRS ratings of rigidity at the elbow and wrist; characterization of such relationships allows interpretation of impedance measurements in terms of the clinical rating scales.


Subject(s)
Muscle Rigidity/physiopathology , Parkinson Disease/physiopathology , Severity of Illness Index , Biomechanical Phenomena , Elbow/physiopathology , Humans , Mathematical Computing , Models, Biological , Movement/physiology , Reproducibility of Results , Wrist/physiopathology
12.
Mov Disord ; 12(1): 24-32, 1997 Jan.
Article in English | MEDLINE | ID: mdl-8990050

ABSTRACT

Clinical assessment of rigidity in parkinsonian patients is largely qualitative. The reliability and validity of the assessments are sometimes in doubt. Several "engineering" methods of quantifying rigidity have been described, but none has been adopted into general clinical practice. A possible reason is that these methods differ in crucial aspects from the clinical exam. We therefore tackled the problem by monitoring the clinical exam itself, using small sensors to measure the forces and displacements applied. Limb impedance (Z) was computed using parameter identification methods and compared to raters' verbalized ratings of rigidity based on a 5-point scale: the Unified Parkinson's Disease Rating System. The qualitative and quantitative estimates of impedance covaried over a fourfold range, depending on the forces imposed and the subject's motor set. Raters differed by up to 1 full point in their mean qualitative ratings and sometimes disagreed on whether levodopa reduced rigidity. This was not due to any significant differences in the overall range of rigidity they evoked, but rather to the way they scored this range [the ratio of mean rating to mean impedance (R/Z) varied between raters and subjects]. On the other hand, the R/Z ratio was reproducible over separate sets of ratings and may therefore serve to convert measured impedance into a standardized rating. Our results indicate that the current clinical exam may be too abbreviated to detect the sometimes quite small reductions in rigidity after levodopa. We conclude that a device that conveniently quantifies the clinical assessment of rigidity is now available and will lead to more standardized protocols for rating rigidity in the near future.


Subject(s)
Muscle Rigidity/diagnosis , Neurologic Examination/statistics & numerical data , Parkinson Disease/diagnosis , Antiparkinson Agents/adverse effects , Antiparkinson Agents/therapeutic use , Humans , Levodopa/adverse effects , Levodopa/therapeutic use , Muscle Rigidity/chemically induced , Neurologic Examination/drug effects , Neurologic Examination/instrumentation , Parkinson Disease/drug therapy , Reproducibility of Results , Transducers
13.
Am J Hypertens ; 9(1): 61-9, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8834708

ABSTRACT

The present study was designed to evaluate the effect of chronic treatment with losartan, an AT1 angiotensin II receptor antagonist, and enalaprilat, an angiotensin converting enzyme inhibitor, on the presynaptic modulation of [3H]-norepinephrine release from isolated atria of spontaneously hypertensive rats (SHR) and their respective control, the Wistar-Kyoto rats (WKY). The rats received either losartan (5 mg/kg/day) or enalaprilat (1 mg/kg/day) for 12 days by means of osmotic minipumps. The atria were isolated and incubated with [3H]-norepinephrine and the release of radioactivity was used as an index of norepinephrine release. The experimental protocol consisted of two electrical stimulations and the drugs were administered 20 min before the second stimulation. The modulatory action of angiotensin II (0.01 and 1 mumol/L), the alpha 2-adrenoceptor agonist, oxymetazoline (1 mumol/L), the alpha 2-adrenoceptor antagonist, idazoxan (1 mumol/L) and the beta 2-adrenoceptor agonist fenoterol (1 mumol/L) were tested. The results show that losartan or enalaprilat both similarly reduced the blood pressure in SHR. However, only the chronic losartan treatment, and not enalaprilat, abolished the facilitatory effect of exogenously administered angiotensin II on the release of radioactivity. The prejunctional alpha 2- and beta 2-adrenoceptor modulatory mechanisms were not altered by either chronic treatments. Similarly, the facilitatory effect of angiotensin II was blocked by acute administration of losartan but not by enalaprilat. Finally, the facilitatory action of bradykinin on the release of radioactivity was unchanged by chronic enalaprilat treatment. These results confirm the presence of facilitatory AT1 angiotensin II receptors on sympathetic nerve terminals of rat atria. These results also confirm that sympathetic nerve terminal blockade by losartan or the blockade of endogenous angiotensin II formation by enalaprilat are likely to participate in the antihypertensive action of AT1 angiotensin II receptor antagonists and angiotensin converting enzyme.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/pharmacology , Antihypertensive Agents/pharmacology , Biphenyl Compounds/pharmacology , Enalaprilat/pharmacology , Heart Atria/metabolism , Imidazoles/pharmacology , Norepinephrine/metabolism , Tetrazoles/pharmacology , Animals , Blood Pressure/drug effects , Body Weight/drug effects , Bradykinin/pharmacology , Losartan , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Renin-Angiotensin System/drug effects
14.
J Physiol ; 488 ( Pt 1): 249-58, 1995 Oct 01.
Article in English | MEDLINE | ID: mdl-8568661

ABSTRACT

1. A reversal in the sign of a cutaneous reflex during walking was recently described in the human. Such reversals were most clearly seen in muscles that were active in two parts of the step cycle, such as the tibialis anterior (TA). The current study determined whether the reversal resulted from differential activation of a single group of motor units. 2. Single motor units were recorded from the TA muscle of healthy human subjects while they walked on a treadmill with a splint that limited motion of the ankle joint. The majority of motor units from which recordings were made (43 out of 46) were active in both the swing phase and the transition from swing to stance, indicating that the two bursts of activity from the TA muscle do not represent the activity of two separate populations of motor units. 3. The firing behavior of three motor units was observed during walking steps when stimuli were applied to the posterior tibial nerve during either the swing phase or the transition from swing to stance. The post-stimulus time histograms indicated that the same motor unit was excited during the swing phase, and inhibited during the transition from swing to stance. 4. The results support the hypothesis that there are parallel excitatory and inhibitory pathways from cutaneous afferents to single motoneurones of the TA muscle. A shift in balance between the two pathways as a function of the step cycle most probably generates the reflex reversal observed.


Subject(s)
Muscle, Skeletal/physiology , Reflex/physiology , Walking/physiology , Electromyography , Evoked Potentials/physiology , Humans , Leg/physiology , Motor Neurons/physiology , Muscle Fibers, Skeletal/physiology , Muscle, Skeletal/cytology , Muscle, Skeletal/innervation , Splints , Time Factors
15.
Biol Cybern ; 70(5): 435-41, 1994.
Article in English | MEDLINE | ID: mdl-8186304

ABSTRACT

Rapid sensory adaptation in the cockroach tactile spine neuron has previously been associated with a labile threshold for action potentials, which changes with the membrane potential by a process involving two time constants. A feed-forward, variable-threshold model has previously been used to account for the frequency response function of the neuron when stimulated with small-signal, white-noise currents. Here, we used a range of accurately controlled steps of extracellular current to stimulate the neuron. The same model was able to predict the individual step responses and could also fit the entire set of step responses from a single neuron if an initial, saturating, static nonlinearity was included. These results indicate that the two-time-constant, variable-threshold model can account for most of the rapidly adapting behavior of the tactile spine neuron.


Subject(s)
Cockroaches/physiology , Neurons, Afferent/physiology , Neurons/physiology , Animals , Electric Conductivity , Electric Stimulation , Female , In Vitro Techniques , Male , Membrane Potentials , Models, Neurological
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