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1.
Synthesis (Stuttg) ; 55(17): 2639-2647, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37790600

ABSTRACT

This short review summarizes our laboratory's development of benzylboronic esters as nucleophiles. Activation of the benzylboronic ester is achieved by irreversible coordination of an alkyllithium Lewis base to form a nucleophilic benzylboronate. This boronate was found to react with aldehydes, imines, ketones and alkyl bromides. A copper catalyst was employed in reactions of the boronate with epoxides and aziridines.

3.
Trials ; 23(1): 175, 2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35197100

ABSTRACT

BACKGROUND: The national opioid crisis has disproportionately burdened rural White populations and American Indian/Alaska Native (AI/AN) populations. Therefore, Cherokee Nation and Emory University public health scientists have designed an opioid prevention trial to be conducted in rural communities in the Cherokee Nation (northeast Oklahoma) with AI and other (mostly White) adolescents and young adults. Our goal is to implement and evaluate a theory-based, integrated multi-level community intervention designed to prevent the onset and escalation of opioid and other drug misuse. Two distinct intervention approaches-community organizing, as implemented in our established Communities Mobilizing for Change and Action (CMCA) intervention protocol, and universal school-based brief intervention and referral, as implemented in our established Connect intervention protocol-will be integrated with skill-based training for adults to strengthen social support for youth and also with strategic media. Furthermore, we will test systems for sustained implementation within existing organizational structures of the Cherokee Nation and local schools and communities. This study protocol describes the cluster randomized trial, designed to measure implementation and evaluate the effectiveness on primary and secondary outcomes. METHODS: Using a cluster randomized controlled design and constrained randomization, this trial will allocate 20 high schools and surrounding communities to either an intervention or delayed-intervention comparison condition. With a proposed sample of 20 high schools, all enrolled 10th grade students in fall 2021 (ages 15 to 17) will be eligible for participation. During the trial, we will (1) implement interventions through the Cherokee Nation and measure implementation processes and fidelity, (2) measure opioid and other drug use and secondary outcomes every 6 months among a cohort of high school students followed over 3 years through their transition out of high school, (3) test via a cluster randomized trial the effect of the integrated CMCA-Connect intervention, and (4) analyze implementation costs. Primary outcomes include the number of days during the past 30 days of (1) any alcohol use, (2) heavy alcohol use (defined as having at least four, among young women, or five, among young men, standard alcoholic drinks within a couple of hours), (3) any marijuana use, and (4) prescription opioid misuse (defined as "without a doctor's prescription or differently than how a doctor or medical provider told you to use it"). DISCUSSION: This trial will expand upon previous research advancing the scientific evidence regarding prevention of opioid and other drug misuse during the critical developmental period of late adolescent transition to young adulthood among a sample of American Indian and other youth living within the Cherokee Nation reservation. TRIAL REGISTRATION: ClinicalTrials.gov NCT04839978 . Registered on April 9, 2021. Version 4, January 26, 2022.


Subject(s)
Drug Misuse , Opioid-Related Disorders , Adolescent , Adult , Alcohol Drinking/prevention & control , Female , Humans , Male , Opioid-Related Disorders/diagnosis , Opioid-Related Disorders/epidemiology , Opioid-Related Disorders/prevention & control , Randomized Controlled Trials as Topic , Schools , Students , Young Adult
4.
BMC Med Inform Decis Mak ; 21(1): 8, 2021 01 06.
Article in English | MEDLINE | ID: mdl-33407427

ABSTRACT

BACKGROUND: The patient ranking process for donor lung allocation in the United States is carried out by a classification-based, computerized algorithm, known as the match system. Experts have suggested that a continuous, points-based allocation framework would better serve waiting list candidates by removing hard boundaries and increasing transparency into the relative importance of factors used to prioritize candidates. We applied discrete choice modeling to match run data to determine the feasibility of approximating current lung allocation policy by one or more composite scores. Our study aimed to demystify the points-based approach to organ allocation policy; quantify the relative importance of factors used in current policy; and provide a viable policy option that adapts the current, classification-based system to the continuous allocation framework. METHODS: Rank ordered logistic regression models were estimated using 6466 match runs for 5913 adult donors and 534 match runs for 488 pediatric donors from 2018. Four primary attributes are used to rank candidates and were included in the models: (1) medical priority, (2) candidate age, (3) candidate's transplant center proximity to the donor hospital, and (4) blood type compatibility with the donor. RESULTS: Two composite scores were developed, one for adult and one for pediatric donor allocation. Candidate rankings based on the composite scores were highly correlated with current policy rankings (Kendall's Tau ~ 0.80, Spearman correlation > 90%), indicating both scores strongly reflect current policy. In both models, candidates are ranked higher if they have higher medical priority, are registered at a transplant center closer to the donor hospital, or have an identical blood type to the donor. Proximity was the most important attribute. Under a points-based scoring system, candidates in further away zones are sometimes ranked higher than more proximal candidates compared to current policy. CONCLUSIONS: Revealed preference analysis of lung allocation match runs produced composite scores that capture the essence of current policy while removing rigid boundaries of the current classification-based system. A carefully crafted, continuous version of lung allocation policy has the potential to make better use of the limited supply of donor lungs in a manner consistent with the priorities of the transplant community.


Subject(s)
Tissue and Organ Procurement , Adult , Child , Humans , Lung , Policy , Tissue Donors , United States , Waiting Lists
5.
Lab Anim ; 53(4): 383-393, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30126336

ABSTRACT

The turquoise killifish Nothobranchius furzeri is an increasingly popular model species for comparative vertebrate research, and the basic physiology including responses to stressful stimuli are of primary interest. We exposed adult killifish to a single or repeated periods of acute confinement followed by analysis of tissue cortisol and plasma cortisol concentrations. Individuals were also sampled for messenger RNA (mRNA) expression of corticotropin-releasing hormone (CRH), mineralocorticoid receptor (MR), and glucocorticoid receptor (GR) in the brain to examine the effects of repeated stress events on constitutive expression of these important stress axis components. Following a single 30-minute confinement stress, male plasma cortisol significantly differed from baseline (p = 0.04). Both male and female whole-body cortisol were significantly increased (p = 0.004 and p = 0.04, respectively) at 15 and 30 minutes poststress. Despite obvious dimorphic behavior and morphology, cortisol concentrations did not differ between the sexes. Exposure to daily repeated confinement for one week altered the cortisol response in both sexes. Time 0, 15, and 60 minutes poststress cortisol concentrations were depressed in repeatedly stressed males (p ≤ 0.05), and times 0, 30 and 120 minutes poststress cortisol concentrations were depressed in repeatedly stressed females (p ≤ 0.05). Constitutive expression of CRH, MR, and GR mRNA in the brain following one week of repeated stress events did not differ among treatments or sexes. This study introduces the first description of hypothalamic-pituitary-interrenal axis activity in this important model species. Reduced cortisol production in repeatedly stressed adult killifish suggests acclimation to repeated stressors. Furthermore, acclimation was rapid, and plasma cortisol concentrations altered significantly in as little as one week.


Subject(s)
Acclimatization , Cyprinodontiformes/physiology , Hydrocortisone/metabolism , Animals , Cyprinodontiformes/genetics , Female , Fish Proteins/genetics , Fish Proteins/metabolism , Gene Expression Profiling , Hydrocortisone/blood , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Random Allocation , Sex Factors , Stress, Physiological
6.
Am J Public Health ; 108(2): 259-261, 2018 02.
Article in English | MEDLINE | ID: mdl-29267057

ABSTRACT

OBJECTIVES: To evaluate effects of 2 alcohol prevention interventions-Communities Mobilizing for Change on Alcohol (CMCA), a community organizing intervention designed to reduce youth alcohol access, and CONNECT, an individual-level screening and brief intervention approach-on other drug use outcomes. METHODS: We conducted a community intervention trial with quarterly surveys over 3 years (2012-2015) of high school students living within the jurisdictional service area of the Cherokee Nation in Oklahoma. We used generalized estimating equations and linear probability models to examine intervention spillover effects on other drug use. RESULTS: We found significant reductions in drug use other than alcohol attributable to CMCA and CONNECT. CMCA was associated with a 35% reduction in chewing tobacco use, a 39% reduction in marijuana use, and a 48% reduction in prescription drug misuse. CONNECT was associated with a 26% reduction in marijuana use and a 31% reduction in prescription drug misuse. CONCLUSIONS: Nonalcohol drug use was consistently reduced as a result of 2 theoretically and operationally distinct alcohol prevention strategies. Evaluations of alcohol prevention efforts should continue to include other drug use to understand the broader effects of such interventions.


Subject(s)
Alcohol Drinking/prevention & control , Community-Based Participatory Research , Indians, North American/statistics & numerical data , Adolescent , Alcohol Drinking/trends , Female , Humans , Male , Marijuana Smoking/prevention & control , Oklahoma , Prescription Drug Misuse/prevention & control , Tobacco Products , United States
7.
Addiction ; 113(4): 647-655, 2018 04.
Article in English | MEDLINE | ID: mdl-29178239

ABSTRACT

AIMS: We evaluated the effects of a community organizing intervention, Communities Mobilizing for Change on Alcohol (CMCA), on the propensity of retail alcohol outlets to sell alcohol to young buyers without age identification and on alcohol acquisition behaviors of underage youth. DESIGN: Random assignment of community to treatment (n = 3) or control (n = 2). Student surveys were conducted four times per year for 3 years; the cohort was in 9th and 10th grades in the 2012-13 academic year. Alcohol purchase attempts were conducted every 4 weeks at alcohol retailers in each community (31 repeated waves). SETTING: The Cherokee Nation, located in northeastern Oklahoma, USA. PARTICIPANTS: A total of 1399 high school students (50% male; 45% American Indian) and 113 stores licensed to sell alcohol across five study communities. INTERVENTION: Local community organizers formed independent citizen action teams to advance policies, procedures and practices of local institutions in ways to reduce youth access to alcohol and foster community norms opposed to teen drinking. MEASUREMENTS: Perceptions regarding police enforcement and perceived difficulty of and self-reported actual acquisition of alcohol from parents, adults, peers and stores. FINDINGS: Alcohol purchases by young-appearing buyers declined significantly, an 18 [95% confidence interval (CI) = 3, 33] percentage-point reduction over the intervention period. Student survey results show statistically significant differences in the trajectory of perceived police enforcement, increasing 7 (4, 10) percentage points, alcohol acquisition from parents, decreasing 4 (0.1, 8) percentage points, acquisition from 21+ adults, decreasing 6 (0.04, 11) percentage points, from < 21 peers decreasing 8 (3, 13) percentage points and acquisition from stores decreasing 5 (1, 9) percentage points. CONCLUSIONS: A community organizing intervention, Communities Mobilizing for Change on Alcohol (CMCA), is effective in reducing the availability of alcohol to underage youth in the United states. Furthermore, results indicate that the previously reported significant effects of CMCA on teen drinking operate, at least in part, through effects on alcohol access.


Subject(s)
Community Participation , Indians, North American , Underage Drinking/prevention & control , Adolescent , Alcoholic Beverages/supply & distribution , Female , Humans , Male , Oklahoma
8.
Am J Public Health ; 107(3): 453-459, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28103073

ABSTRACT

OBJECTIVES: To evaluate the effectiveness of a multilevel intervention designed to prevent underage alcohol use among youths living in the Cherokee Nation. METHODS: We randomly assigned 6 communities to a control, Communities Mobilizing for Change on Alcohol (CMCA; a community-organizing intervention targeting alcohol access) only, CONNECT (a school-based universal screening and brief intervention) only, or a combined condition. We collected quarterly surveys 2012-2015 from students starting in 9th and 10th grades and ending in 11th and 12th grades. Response rates ranged from 83% to 90%; 46% of students were American Indian (of which 80% were Cherokee) and 46% were White only. RESULTS: Students exposed to CMCA, CONNECT, and both showed a significant reduction in the probability over time of 30-day alcohol use (25%, 22%, and 12% reduction, respectively) and heavy episodic drinking (24%, 19%, and 13% reduction) compared with students in the control condition, with variation in magnitude of effects over the 2.5-year intervention period. CONCLUSIONS: CMCA and CONNECT are effective interventions for reducing alcohol use among American Indian and other youths living in rural communities. Challenges remain for sustaining intervention effects.


Subject(s)
Alcohol Drinking/prevention & control , Indians, North American , White People , Adolescent , Community-Based Participatory Research , Female , Humans , Male , Risk Factors , United States
9.
AIDS Rev ; 18(3): 151-157, 2016.
Article in English | MEDLINE | ID: mdl-27438575

ABSTRACT

There is evidence that the transmission and acute phase of HIV infection triggers an immune response capable of controlling HIV subverted by the process of virus integration, essential to the replicative cycle of retroviruses. We review here two aspects that deserve consideration in light of recent developments concerning HIV transmission and vaccine development: vaccines directed against transmitted/founder viruses, and a reconsideration of inactivation as a viable means to obtain a preventive HIV vaccine. Since 80% of sexually transmitted HIV infections are caused by a single transmitted/founder variant, it is appropriate to target transmitted/founder viruses for vaccine development. Transmitted/founder virus transmission is subject to strong natural selection based on conserved signatures present in all forms of transmitted/founder HIV viruses. This provides an opportunity to pursue inactivation methods of vaccine development that allow antigenic preservation of HIV transmitted/founder viruses. The presentation to the immune system of an inactivated but antigenically preserved transmitted/founder virus should allow the development of an effective immune response against transmitted/founder viruses. This could be the base for an inactivated transmitted/founder virus HIV vaccine. We have devised a method of inactivation of HIV reverse transcriptase through the use of a novel photo-labeling procedure based on the use of photo-labeled analogs of antiretroviral compounds with specific affinity for HIV reverse transcriptase. We believe this method fulfills the required conditions for an effective preventive vaccine development: inactivation and antigenic preservation.


Subject(s)
AIDS Vaccines/immunology , HIV Infections/immunology , HIV Infections/prevention & control , HIV-1/genetics , HIV-1/immunology , Humans , Vaccines, Synthetic/immunology , Virus Inactivation
11.
Thromb Haemost ; 109(6): 1158-69, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23571406

ABSTRACT

Previously, we presented the electrolytic inferior vena cava (IVC) model (EIM) during acute venous thrombosis (VT). Here, we present our evaluation of the EIM for chronic VT time points in order to determine whether this model allows for the study of thrombus resolution. C57BL/6 mice (n=191) were utilised. In this model a copper-wire, inserted into a 25-gauge needle, is placed in the distal IVC and another subcutaneously. An electrical current (250 µAmp/15 minutes) activates the endothelial cells, inducing thrombogenesis. Ultrasound, thrombus weight (TW), vein wall leukocyte counts, vein wall thickness/fibrosis scoring, thrombus area and soluble P-selectin (sP-sel) were performed at baseline, days 1, 2, 4, 6, 9, 11 and 14, post EIM. A correlation between TW and sP-sel was also determined. A thrombus formed in each mouse undergoing EIM. Blood flow was documented by ultrasound at all time points. IVC thrombus size increased up to day 2 and then decreased over time, as shown by ultrasound, TW, and sP-sel levels. TW and sP-sel showed a strong positive correlation (r=0.48, p<0.0002). Vein wall neutrophils were the most common cell type present in acute VT (up to day 2) with monocytes becoming the most prevalent in chronic VT (from day 6 to day 14). Thrombus resolution was demonstrated by ultrasound, TW and thrombus area. In conclusion, the EIM produces a non-occlusive and consistent IVC thrombus, in the presence of constant blood flow, allowing for the study of VT at both acute and chronic time points. Thrombus resolution was demonstrated by all modalities utilised in this study.


Subject(s)
Disease Models, Animal , Thrombosis/pathology , Thrombosis/therapy , Vena Cava, Inferior/pathology , Animals , Blood Flow Velocity , Copper/chemistry , Electric Stimulation , Inflammation , Leukocytes/cytology , Male , Mice , Mice, Inbred C57BL , Monocytes/cytology , P-Selectin/blood , Phlebography , Time Factors , Venous Thrombosis
12.
Appl Opt ; 50(20): 3703-10, 2011 Jul 10.
Article in English | MEDLINE | ID: mdl-21743584

ABSTRACT

An etched calcite square-wave retarder is designed, fabricated, and demonstrated as an illuminator for an interlaced polarization computer-generated hologram (PCGH). The calcite square-wave retarder enables alternating columns of orthogonal linear polarizations to illuminate the interlaced PCGH. Together, these components produce a speckled, tangentially polarized PCGH diffraction pattern with a measured ratio of polarization of 84% and a degree of linear polarization of 0.81. An experimental alignment tolerance analysis is also reported.

13.
Opt Lett ; 35(20): 3423-5, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20967087

ABSTRACT

An interlaced polarization computer-generated hologram (PCGH) is designed to produce specific irradiance and polarization states in the image plane. The PCGH produces a tangentially polarized annular pattern with correlated speckle, which is achieved by a novel application of the diffuser optimization method. Alternating columns of orthogonal linear polarizations illuminate an interlaced PCGH, producing a ratio of polarization of 88% measured on a fabricated sample. The demonstrated technique can be applied to designs for arbitrary irradiance and polarization states in the image plane.

14.
Am Fam Physician ; 81(9): 1111-7, 2010 May 01.
Article in English | MEDLINE | ID: mdl-20433127

ABSTRACT

Pelvic organ prolapse, or genital prolapse, is the descent of one or more of the pelvic structures (bladder, uterus, vagina) from the normal anatomic location toward or through the vaginal opening. Women of all ages may be affected, although pelvic organ prolapse is more common in older women. The cause is a loss of pelvic support from multiple factors, including direct injury to the levator ani, as well as neurologic injury from stretching of the pudendal nerves that may occur with vaginal childbirth. Previous hysterectomy for pelvic organ prolapse; ethnicity; and an increase in intra-abdominal pressure from chronic coughing, straining with constipation, or repeated heavy lifting may contribute. Most patients with pelvic organ prolapse are asymptomatic. A sense of bulging or protrusion in the vagina is the most specific symptom. Evaluation includes a systematic pelvic examination. Management options for women with symptomatic prolapse include observation, pelvic floor muscle training, mechanical support (pessaries), and surgery. Pessary use should be considered before surgery in women who have symptomatic prolapse. Most women can be fitted with a pessary regardless of the stage or site of predominant prolapse. Surgical procedures are obliterative or reconstructive.


Subject(s)
Health Behavior , Health Knowledge, Attitudes, Practice , Pelvic Organ Prolapse/therapy , Women's Health , Exercise , Female , Humans , Muscle Contraction , Patient Education as Topic , Pessaries
15.
Article in English | MEDLINE | ID: mdl-14530844

ABSTRACT

A 62-year-old homemaker underwent an uneventful TVT (tension-free vaginal tape) procedure. Eleven days postoperatively she presented to the Emergency Department with agonizing low abdominal pain, elbow pain, fever, and drainage from her suprapubic puncture sites. Her evaluation was consistent with a diagnosis of necrotizing fasciitis and she was started on antibiotics and taken to surgery for exploration and debridement, where the diagnosis was confirmed. This is the first report of necrotizing fasciitis following TVT placement.


Subject(s)
Fasciitis, Necrotizing/etiology , Fasciitis, Necrotizing/therapy , Plastic Surgery Procedures/adverse effects , Urinary Incontinence, Stress/surgery , Anti-Bacterial Agents , Combined Modality Therapy , Debridement/methods , Drug Therapy, Combination/therapeutic use , Fasciitis, Necrotizing/diagnosis , Female , Follow-Up Studies , Humans , Middle Aged , Postoperative Complications , Plastic Surgery Procedures/methods , Risk Assessment , Severity of Illness Index , Surgical Mesh , Treatment Outcome , Urinary Incontinence, Stress/diagnosis
16.
Mov Disord ; 18(7): 764-72, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12815655

ABSTRACT

A lower prevalence of Parkinson's disease (PD) has been reported for Chinese populations, but it is unclear whether this observation reflects a lower disease risk or is an artifact of case finding. We ascertained the prevalence of PD in elderly residents of an area that was a composite of 27 urban and rural communities of Greater Beijing, China. A team of university neurologists went door-to-door throughout the study area, examining 5,743 residents (at age 55 years or older) and made preliminary determinations of which residents had PD or other types of parkinsonism. Final determinations were made after follow-up and reevaluation of those persons who were either deemed to have parkinsonism or were suspected of having the condition (n = 144; median follow-up = 40 months). Based on stringent diagnostic criteria, 110 persons were identified to have parkinsonism, of whom 64 (58%) had PD. The prevalence of PD increased with advancing age and was about 1% overall and for each gender. In rural communities, 22 persons had PD, but 20 persons (91%) were first diagnosed for this condition by the study neurologists. The prevalence figures obtained in this study are similar to some of the highest prevalence figures reported in the West.


Subject(s)
Parkinson Disease/epidemiology , Rural Population/statistics & numerical data , Urban Population/statistics & numerical data , Aged , Aged, 80 and over , China/epidemiology , Cross-Cultural Comparison , Cross-Sectional Studies , Female , Health Surveys , Humans , Incidence , Male , Middle Aged , Neurologic Examination , Parkinson Disease/diagnosis , Parkinsonian Disorders/diagnosis , Parkinsonian Disorders/epidemiology
17.
Am J Vet Res ; 63(5): 738-43, 2002 May.
Article in English | MEDLINE | ID: mdl-12013477

ABSTRACT

OBJECTIVE: To describe the ultrasonographic and quantitative histologic effect of injecting 2% iodine in almond oil (IAO) and ethanolamine oleate (EO) in the medial and middle patellar ligaments of horses and to determine whether a difference in response exists between IAO and EO treatment. ANIMALS: 10 healthy horses. PROCEDURE: In 5 horses, the medial and middle patellar ligaments of 1 limb were injected with EO, whereas IAO was injected in the medial and middle patellar ligaments of another 5 horses. Ultrasonographic evaluation was performed on the experimental and control limb before injection of IAO and EO and prior to euthanasia to determine cross-sectional area and evaluate fiber pattern. The patellar ligaments were harvested 2 weeks after injection and examined histologically to evaluate the inflammatory response, fibroplasia, and chondroid metaplasia. RESULTS: Injection of the patellar ligaments with IAO resulted in a greater increase in cross-sectional area on ultrasonography than EO. Both agents caused a decrease in echogenicity of the ligament. Histologically, significantly greater infiltration of inflammatory cells and fibroplasia developed after injection with IAO, compared with EO. Both agents resulted in significantly greater fibroplasia relative to control specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Injection of the medial and middle patellar ligaments with IAO induces more severe inflammation and fibroplasia than EO. Maturation of the inflammatory and fibrous response may contribute to resolution or attenuation of upward fixation of the patella by subsequent stiffening of the ligaments.


Subject(s)
Horses/anatomy & histology , Iodine/therapeutic use , Oleic Acids/therapeutic use , Patellar Ligament/cytology , Patellar Ligament/drug effects , Sclerosing Solutions/therapeutic use , Animals , Iodine/adverse effects , Male , Oleic Acids/adverse effects , Patellar Ligament/diagnostic imaging , Patellar Ligament/metabolism , Random Allocation , Sclerosing Solutions/adverse effects , Ultrasonography
18.
Protein Expr Purif ; 21(3): 367-77, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11281710

ABSTRACT

Stromal-cell-derived factor-1 (SDF-1alpha) is an 8-kDa chemokine that is constitutively expressed in bone-marrow-derived stromal cells and has been identified as a ligand for the CXCR4 receptor. We produced the chemokine recombinantly as methionine-SDF-1alpha in Escherichia coli without the leader peptide sequence. The protein was denatured, refolded, and further purified by reversed-phase HPLC. SDF-1alpha was shown to be >95% pure as judged by SDS-PAGE. The final yield of purified and refolded SDF-1alpha was 1-2 mg per gram of wet cell paste. The refolded protein is a ligand for the CXCR4 receptor and has been used to block HIV-mediated cell fusion and downmodulates the CXCR4 receptor. Our ability to purify hundreds of milligrams of refolded protein allowed us to conduct detailed studies of the biophysical properties of the protein. We have used a combination of biophysical techniques to study the solution properties of SDF-1alpha. The average mass of SDF-1alpha, as determined by static light scattering, gave us the first indications that the chemokine may self-associate. Further investigation with sedimentation velocity ultracentrifugation confirmed the existence of two species. The measured s(20, W) values defined two masses corresponding to monomer and dimer. Finally, sedimentation equilibrium ultracentrifugation and dynamic light scattering yielded a composite value of 150 +/- 30 microM for the dimerization constant. We conclude that SDF-1alpha exists in a monomer-dimer equilibrium.


Subject(s)
Anti-HIV Agents/chemistry , Anti-HIV Agents/isolation & purification , Chemokines, CXC/chemistry , Chemokines, CXC/isolation & purification , Anti-HIV Agents/metabolism , Chemokine CXCL12 , Chemokines, CXC/genetics , Chemokines, CXC/metabolism , Chromatography, Gel , Chromatography, High Pressure Liquid , Circular Dichroism , Dimerization , Humans , Light , Molecular Weight , Protein Denaturation , Protein Folding , Protein Renaturation , Protein Sorting Signals , Protein Structure, Quaternary , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Scattering, Radiation , Sequence Analysis, Protein , Solutions , Thermodynamics , Ultracentrifugation
19.
J Virol ; 75(2): 903-9, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11134303

ABSTRACT

Our group and others have recently demonstrated the ability of recombinant baculoviruses to transduce mammalian cells at high frequency. To further characterize the use of baculovirus as a mammalian gene delivery system, we examined the status of transduced DNA stably maintained in Chinese hamster ovary (CHO) cells. Four independent clones carrying two introduced markers, the genes for neomycin resistance (Neo) and green fluorescent protein (GFP), were selected. PCR analysis, Southern blotting, and DNA sequencing showed that discrete portions of the 148-kb baculovirus DNA were present as single-copy fragments ranging in size from 5 to 18 kb. Integration into the CHO cell genome was confirmed by fluorescent in situ hybridization (FISH) analysis. For one clone, the left and right viral/chromosomal junctions were determined by DNA sequencing of inverse PCR products. Similarly, for a different clone, the left viral/chromosomal junction was determined; however, the right junction sequence revealed the joining to another viral fragment by a short homology (microhomology), a hallmark of illegitimate recombination. The random viral breakpoints and the lack of homology between the virus and flanking chromosomal sequences are also suggestive of an illegitimate integration mechanism. To examine the long-term stability of reporter gene expression, all four clones were grown continuously for 36 passages in either the presence or absence of selection for Neo. Periodic assays over a 5-month period showed no loss of GFP expression for at least two of the clones. This report represents the first detailed analysis of baculovirus integrants within mammalian cells. The potential advantages of the baculovirus system for the stable integration of genetic material into mammalian genomes are discussed.


Subject(s)
Baculoviridae/genetics , DNA, Recombinant/genetics , Genetic Vectors , Transduction, Genetic , Virus Integration , Animals , Base Sequence , Blotting, Southern , CHO Cells , Cricetinae , Genes, Reporter , Green Fluorescent Proteins , In Situ Hybridization, Fluorescence , Luminescent Proteins/biosynthesis , Luminescent Proteins/genetics , Molecular Sequence Data , Polymerase Chain Reaction/methods , Recombinant Proteins/biosynthesis , Sequence Analysis, DNA
20.
Hybridoma ; 19(4): 297-302, 2000 Aug.
Article in English | MEDLINE | ID: mdl-11001402

ABSTRACT

Class-switched, affinity-matured murine monoclonal antibody (MAb) producing cell lines reactive with PED/PEA-15 were generated and isolated in less than 4 weeks following polynucleotide immunizations using only 5 microg of DNA in conjunction with the Powderject gene gun. Somatic fusions of peripheral lymph node cells were performed 13 days after initiating delivery of DNA encoding the target antigen. The data presented demonstrates the rapid production, identification, and characterization of class-switched, affinity-matured MAbs that bind PED/PEA-15. The reported strategy enabled the rapid development of MAbs that are useful in enzyme-linked immunoadsorbent assay (ELISA), Western blotting, and immunoprecipitations.


Subject(s)
Antibodies, Antinuclear/biosynthesis , Antibodies, Monoclonal/biosynthesis , Antibody Affinity/immunology , DNA/immunology , Histocompatibility Antigens Class I/genetics , Phosphoproteins/genetics , Animals , Antibodies, Antinuclear/immunology , Antibodies, Monoclonal/immunology , Antibody Specificity/immunology , Apoptosis Regulatory Proteins , Blotting, Western , DNA Primers/chemistry , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Histocompatibility Antigens Class I/immunology , Humans , Immunization/methods , Intracellular Signaling Peptides and Proteins , Mice , Phosphoproteins/immunology , Polymerase Chain Reaction , Recombinant Fusion Proteins
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