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D W Wong

Publications and source records attributed to D W Wong.

At least 37 records · Page 2Linked to original sources
PubMed1995

Collagen induces cytokine production by synovial fluid mononuclear cells in rheumatoid arthritis.

Synovial fluid (SF) mononuclear cells (MNC) from 13 patients with rheumatoid arthritis (RA) and 12 patients with other arthritic diseases (OD) including osteoarthritis (OA), gout and spondyloarthritis (SA) were cultured in the presence of collagen types I and II or lipopolysaccharide (LPS) for 24 h. Interleukin-1 (IL-1), IL-6 and tumor necrosis factor-alpha (TNF-alpha) in the SF and culture supernatants were assayed using ELISA. The results showed that one-half of the RA patients with high SF monocyte count had high SF IL-6 levels that coincided with the high spontaneous release of IL-6 by SF MNC. In the other RA patients with lower SF monocyte count, type II collagen induced significantly higher IL-1 beta than the medium control levels by SF MNC (P < 0.01) or that of the other diseases (P < 0.01). Similarly, type II collagen-induced IL-6 and TNF-alpha production rose significantly (P < 0.01) from SF MNC of RA but less from OD (P < 0.05). In addition, type I collagen could also induce IL-1, IL-6 and TNF-alpha in these samples from RA and OD patients but was less potent than type II collagen. Our results indicate that collagen-induced cytokines may be important in the pathogenesis of the disease.

Arthritis, Rheumatoid↗
PubMed1995

Detection of acute infection/inflammation with Tc-99m labeled intact polyvalent human IgG.

Intact polyvalent human immune globulin (IgG) labeled with Tc-99m by a mild chemical method was investigated with animals infected with either S. aureus or E. coli in the thigh muscle. Focal infection was clearly visualized by Tc-99m IgG scintigraphy within 1 h postinjection. Tc-99m IgG appeared to be concentrated in the liver, spleen, kidneys and urinary bladder. It cleared rapidly via the kidneys resulting minimal of tissue background activity and high infection-to-normal organ ratios. At 24 h postinjection, the ratios of infectious lesion to blood, normal muscle and bone averaged 10:1, 23:1, and 24:1 for S. aureus infection vs 4:1, 9:1 and 9:1 for E. coli infection, respectively. Tc-99m labeled IgG also concentrated in terpentine-induced aseptic inflammatory lesion with a target-to-blood ratio of 4:1, bone 6:1 and normal muscle about 10:1. These findings suggest potential value of Tc-99m IgG as an imaging agent for the early detection of focal infection and inflammation.

Animals↗
PubMed1991

Expression of the transglutaminase gene in Escherichia coli.

1. The cDNA gene coding for the enzyme transglutiminase (EC 2.3.2.13) was cloned into the pUC18 oriented for expression from the lac promoter. 2. DNA sequencing of the 5' end showed that the cDNA was missing the sequence coding of the N-terminal 30 amino acids. 3. The truncated gene was then cloned into pKK233-2, and the recombinant product was produced in Escherichia coli. 4. A gene construct coding for the complete protein was generated by inserting an oligonucleotide for the missing 30 amino acids into the Eco RI site of the pUC18 clone. 5. A consensus Shine-Dalgarno sequence and translational start codon were positioned at the 5' end of the linker. 6. Immunoblotting experiments of E. coli JM105(pUC18-TGase) indicated the expression of the transglutaminase gene. 7. The cell lysate as well as the partially purified transglutaminase showed no detectable enzyme activity.

Amino Acid Sequence↗
PubMed1990

Expression of recombinant bovine beta-lactoglobulin in Escherichia coli.

Bovine beta-lactoglobulin A was expressed in Escherichia coli in its mature form. The gene was constructed using a cDNA clone which coded for amino acid residues Leu-11 to Ile-162 and a synthetic oligonucleotide coding for the initial 10 amino acids preceded by a translational start. The met-beta-lactoglobulin was expressed using a tac promoter vector, pTTQ18, and accounted for approximately 15% of the total cellular protein. The recombinant met-beta-lactoglobulin migrated with the same molecular weight as native beta-lactoglobulin A on SDS-PAGE. The majority of the met-beta-lactoglobulin produced was found in an insoluble form but could be solubilized using guanidine-HCl. The renatured preparation was greater than 80% pure and migrated similarly to purified beta-lactoglobulin A under nondenaturing conditions.

Amino Acid Sequence↗
PubMed1989

In vivo assessment of 111In-labeled hematoporphyrin derivative in breast tumor-bearing animals.

The biological behavior of 111In-labeled HPD has been investigated in tumor-bearing animals. Mice mammary adenocarcinomas and 7,12-dimethylbenz(a)anthracine induced breast tumors in Sprague-Dawley female rats were clearly visualized by 111In-HPD nuclear scintigraphy. Optimal scans were obtained after a 48 h delay. In normal and tumor-bearing animals, the highest uptake of 111In-HPD 72 h post-injection was found in the liver, the spleen and the kidneys. Depending on the size and the extent of necrosis, the uptake of 111In-HPD by malignant breast tumors varied from 2.5% injected dose (ID) (range 0.14-5.3% ID) in mice to 1% (range 0.22-8.1% ID) in rats. Benign breast tumor uptake of 111In-HPD was less than 1% ID. No significant amount of the radiopharmaceutical was found in pulmonary abscesses and abdominal cysts (less than 0.1% ID). Scintigrams of these infectious or inflammatory lesions were normal. Malignant tumor to blood, heart and lung ratios averaged 50:1, 10:1 and 3:1 respectively. Tumor to brain ratio ranged from 72 to 444:1.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1989

Scintigraphic detection of atherosclerotic plaques in rabbits with 111In-labeled hematoporphyrin derivative.

The efficacy of 111In-labeled hematoporphyrin derivative (HPD) in localizing and detecting atheromas had been investigated with 10 atherogenic New Zealand white rabbits. Atherosclerotic plaques surgically induced in the abdominal aorta showed selective uptake of 111In-HPD over normal blood vessels averaging 0.01% ID/g tissue (range 0.003-0.023% ID/g). Normal aorta and thoracic artery concentrated an average of 0.0026% ID/g which is less than the mean blood activity of 0.0034% ID/mL. Statistical analysis demonstrated significant difference in the uptake of 111In-HPD by the atherosclerotic plaque segments as compared to normal abdominal aorta (P = 0.0023) and normal thoracic artery (P = 0.0012). In hypercholesteremic rabbits, the mean plaque segment to normal blood vessels ratio was 4:1 (range 2 to 9:1) sufficiently high to permit plaque delineation in the scintigram. Although 111In-HPD showed promise as a plaque imaging agent, further investigation with large animal models such as primates is needed to confirm current findings.

Animals↗
PubMed1988

Nonlinkage of the T cell receptor alpha, beta, and gamma genes to systemic lupus erythematosus in multiplex families.

To test the possibility that T cell antigen receptor (TcR) genes are linked to the genes involved in the pathogenesis of systemic lupus erythematosus (SLE), genomic DNA restriction fragment length polymorphisms were studied, using the Southern blot technique, in 5 families with multiple members with SLE, 14 unrelated SLE patients, and 14 normal controls. Polymorphic patterns were detected with probes for all 3 TcR chains, but there was no significant difference in the distribution of the restriction fragment length polymorphism pattern among the patients, the relatives, and the controls. Furthermore, in the families with at least 2 individuals with the disease, each of the 3 TcR chain genes did not cosegregate with the disease. We conclude that TcR alpha, beta, and gamma chain genes are not likely to be linked to genes related to SLE.

DNA↗
PubMed1988

Cis-acting sequences that modulate atrial natriuretic factor gene expression.

Nucleotide sequences necessary to direct transcription of the gene encoding atrial natriuretic factor (ANF) in neonatal and fetal hearts have been defined by using expression of the prokaryotic marker gene chloramphenicol acetyltransferase (CAT) as a functional assay. Hybrid ANF-CAT genes were introduced into primary cultured cardiocytes by electroporation. A 3.4-kilobase (kb) fragment containing sequences on the 5' side of the ANF gene promoted significant CAT activity in atrial but not ventricular cardiocytes derived from 1-day-old rats. Deletion analysis of putative regulatory regions demonstrated that 2.4 kb of 5' ANF sequences were sufficient for high-level atrial transcription, whereas hybrid genes containing less than 700 base pairs of ANF sequences promoted less CAT activity. Cardiocytes derived from embryonic ventricles expressed the 3.4-kb ANF-CAT hybrid gene at levels comparable to atrial cells, suggesting that the nucleotide sequences controlling developmental regulation of ANF expression are contained in this 5' region. Nucleotide sequence analysis of this 3.6-kb region identified segments that may contribute to the regulated expression of the ANF gene.

Acetyltransferases↗
PubMed1988

Predicting rehabilitation outcomes from clinical and statistical data: a probability model.

This research was focused on the feasibility of a Markov Chain probability model for predicting rehabilitation outcome. A combination of clinical ratings from counselors and statistical data from client files was used to predict 'successful' and 'unsuccessful' outcomes. Predictions were made at three separate time periods: Time 1, during the first week after initial interview; Time 2, during the fourth week after initial interview; and Time 3, during the thirteenth week after initial interview. The final outcome was determined at the end of six months. The research sample consisted of seventy-one clients from two private rehabilitation agencies, all of whom suffered from work-related injuries or illnesses. The results of this research indicate that a Markov Chain probability model is quite feasible for predicting rehabilitation outcomes. In addition, it was observed that the predictions generally followed a progression over time toward stronger and more accurate predictions for both 'success' and 'failure'. With only one exception, occurring at Time 1, the clinical ratings from the counselors were shown to be stronger predictors than the statistical data from case files. This finding is inconsistent with previous studies. It is suggested that a model such as this can serve to alert counselors to the possible need for different or more innovative strategies for service to clients who show a poor probability for success.

Accidents, Occupational↗
PubMed1987

A rapid and efficient physiologic chemical method of labeling plasma proteins with indium-111.

A rapid physiologic chemical method had been developed for labeling plasma proteins with 111In. Human serum albumin, IgG, fibrinogen, transferrin, lactoferrin and the enzyme bovine thrombin had been successfully labeled with exceptionally high labeling yields of greater than 98%. In vitro bioassays confirmed that 111In-fibrinogen and 111In-thrombin retained 96-99% of their biochemical activities after labeling with the radionuclide. All radiolabeled proteins were stable at 2-8 degrees C in excess of 3 week periods without elution of the "label" or any significant loss of biological activity.

Blood Proteins↗
PubMed1987

Conversion of 111In-oxine to 111In trichloride by acid hydrolysis.

The lipophilic complex 111In-oxine was converted back to 111InCl3 by acid hydrolysis with 0.1 N HCl. Greater than 99% of the starting material was converted to 111InCl3 with a purity of 99.6%. Unlabeled oxine was completely removed by chloroform extraction. Current experimental data suggest that 111In-oxine is unstable in weak acidic medium.

Hydrochloric Acid↗
PubMed1984

Lymphoma of the heart.

A case of malignant lymphoma involving the heart is reported. The patient presented with symptoms of cardiac decompensation. The echocardiographic findings of an echogenic mass arising from the pulmonary valve as well as demonstration of soft tissue density diffusely infiltrating the heart and mediastinum was confirmed by computer tomography and angiography. Although the findings on the noninvasive studies were highly indicative of tumor involvement, the temporal association of the symptoms to a motor vehicle accident lead to the erroneous diagnosis of intracardiac and mediastinal hematoma.

Diagnosis, Differential↗
PubMed1984

A simple and efficient method of labeling hematoporphyrin derivative with 111In.

Hematoporphyrin derivative (HPD) has been successfully labeled with 111In by a simple and efficient chemical process. Greater than 96% of the radionuclide is firmly bound to HPD as demonstrated by ITLC and acid precipitation radioanalyses. The radiopharmaceutical is stable at room temperature in excess of two weeks without any significant amount of dissociation of the label from the radioactive parent compound.

Hematoporphyrin Derivative↗
PubMed1984

Aortic dissection: CT and angiographic comparisons.

Computed tomography and aortography were compared in a retrospective study of 35 patients with aortic dissection of type A (n = 17) and type B (n = 18). Based on classical diagnostic criteria such as evidence of two channels, intimal flaps and displaced intimal calcification, computed tomography was able to confirm the presence and type of aortic dissection in 32 patients. Dynamic computed tomography was used in 20 cases. When bolus technique was applied appropriately (16/20), computed tomography clearly differentiated the two channels and identified each by its time density characteristics. In 5 of the 35 patients included, the aortographic diagnosis was equivocal because no definite second channel was identified. In these, CT was helpful to confirm the diagnosis showing the presence of an intimal flap, displaced intimal calcification and clot in the false channel. It was noted that classical signs of differentiation of the true and false channels by their relationship to intimal calcification and by the anatomic relationship of the two identified channels to each other at different levels of the aorta are not without exceptions. It is concluded that dynamic computed tomography represents a valuable alternative to aortography and is preferred in chronic dissection and follow-up examinations and for the initial workup of patients with a mediastinal mass. However, when a roadmap of the aortic branches is required prior to surgical intervention, aortography remains the procedure of choice.

Adult↗
PubMed1983

In vivo assessment of 99mTc-labeled hematoporphyrin derivative in tumor-bearing animals.

The efficacy of 99mTc-labeled hematoporphyrin derivative in localizing neoplasms has been investigated with tumor-bearing animal models. Spontaneous mammary adenocarcinomas of outbred CFW strain Swiss-Webster white mice and chemical carcinogen induced breast tumors in female Sprague-Dawley white rats were clearly visualized in the scintigrams. Mice tissue distribution data demonstrate favourable tumor to organ ratios sufficiently high to permit tumor detection. [99mTc]HPD appears promising as a tumor imaging agent.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Imaging endocarditis with Tc-99m-labeled antibody--an experimental study: concise communication.

The sensitivity and specificity of Tc-99m-labeled antibacterial antibody (Tc-99m Ab) for detecting bacterial endocarditis were evaluated in an experimental model. Rabbit-produced antistaphylococcal antibody was extracted using Rivanol and chemically labeled with Tc-99m. This Tc-99m Ab was injected intravenously in New Zealand rabbits 24 hr after producing Staphylococcus aureus endocarditis of the aortic valve. Imaging and tissue analyses were performed on the following day. All 11 animals developed S. aureus aortic-valve vegetations and showed increased uptake of Tc-99m Ab at the aortic valve, 118 times higher than at the uninfected tricuspid valve. Although high hepatic radioactivity and anatomic uncertainties interfered with in vivo delineation of these lesions, images of the excised hearts showed all affected valves. Two rabbits inoculated with Escherichia coli did not develop endocarditis and had little uptake of Tc-99m Ab, while six rabbits with enterococcal endocarditis had no uptake of the Tc-99m Ab in their vegetations. The findings suggest potential value of Tc-99m Ab on the rapid diagnosis of endocarditis.

Animals↗