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Featured researches published by R. James Swanson.


Urology | 1987

New method of evaluating sperm morphology with predictive value for human in vitro fertilization

Thinus F. Kruger; Anibal A. Acosta; Kathryn F. Simmons; R. James Swanson; James F. Matta; Lucinda L. Veeck; Mahmood Morshedi; Santiago Brugo

A prospective study was planned to evaluate sperm morphology as a parameter to predict the fertilization outcome in an in vitro fertilization program. Couples applying to in vitro fertilization were admitted into this project when the sperm concentration was greater than 20 million per mL and motility greater than 30 per cent. Based on new strict criteria for evaluating normal sperm morphology, patients were divided prospectively into 2 groups. In group I (25 patients) normal sperm morphology was less than 14 per cent, and in group II (71 patients) normal sperm morphology was greater than 14 per cent, using a threshold established previously. Multiple regression analysis was used to evaluate different parameters: concentration, motility, and morphology against the dependent variables, fertilization, and cleavage. The only factor which was significantly correlated with fertilization and cleavage was normal sperm morphology (P less than 0.0001). The fertilization rate (per oocyte) and the cleavage rate were 49.4 per cent and 47.6 per cent in group I and 88.3 per cent and 87 per cent in group II (P less than 0.0001). The ongoing pregnancy rate per laparoscopy and per embryo transfer was 4 per cent and 5.5 per cent, respectively, in group I and 18.3 per cent and 18.5 per cent, respectively, in group II (no significant difference). This study demonstrates the value of analyzing sperm morphology using the criteria recommended in terms of predicting fertilization and perhaps pregnancy outcome. Patients can be better counseled and the probability of fertilization or no fertilization can be more accurately established. Furthermore a trend is shown in the pregnancy rate that may indicate the importance of the male genome in establishing a pregnancy.


International Journal of Cancer | 2009

A new pulsed electric field therapy for melanoma disrupts the tumor's blood supply and causes complete remission without recurrence

Richard Nuccitelli; Xinhua Chen; Andrei G. Pakhomov; Wallace H. Baldwin; Saleh Sheikh; Jennifer L. Pomicter; Wei Ren; Christopher Osgood; R. James Swanson; Juergen F. Kolb; Stephen J. Beebe; Karl H. Schoenbach

We have discovered a new, ultrafast therapy for treating skin cancer that is extremely effective with a total electric field exposure time of only 180 μsec. The application of 300 high‐voltage (40 kV/cm), ultrashort (300 nsec) electrical pulses to murine melanomas in vivo triggers both necrosis and apoptosis, resulting in complete tumor remission within an average of 47 days in the 17 animals treated. None of these melanomas recurred during a 4‐month period after the initial melanoma had disappeared. These pulses generate small, long‐lasting, rectifying nanopores in the plasma membrane of exposed cells, resulting in increased membrane permeability to small molecules and ions, as well as an increase in intracellular Ca2+, DNA fragmentation, disruption of the tumors blood supply and the initiation of apoptosis. Apoptosis was indicated by a 3‐fold increase in Bad labeling and a 72% decrease in Bcl‐2 labeling. In addition, microvessel density within the treated tumors fell by 93%. This new therapy utilizing nanosecond pulsed electric fields has the advantages of highly localized targeting of tumor cells and a total exposure time of only 180 μsec. These pulses penetrate into the interior of every tumor cell and initiate DNA fragmentation and apoptosis while at the same time reducing blood flow to the tumor. This new physical tumor therapy is drug free, highly localized, uses low energy, has no significant side effects and results in very little scarring.


Pigment Cell & Melanoma Research | 2010

Apoptosis initiation and angiogenesis inhibition: melanoma targets for nanosecond pulsed electric fields

Xinhua Chen; Juergen F. Kolb; R. James Swanson; Karl H. Schoenbach; Stephen J. Beebe

Many effective anti‐cancer strategies target apoptosis and angiogenesis mechanisms. Applications of non‐ionizing, nanosecond pulsed electric fields (nsPEFs) induce apoptosis in vitro and eliminate cancer in vivo; however in vivo mechanisms require closer analysis. These studies investigate nsPEF‐induced apoptosis and anti‐angiogenesis examined by fluorescent microscopy, immunoblots, and morphology. Six hours after treatment with one hundred 300 ns pulses at 40 kV/cm, cells transiently expressed active caspases indicating that caspase‐mediated mechanisms. Three hours after treatment transient peaks in Histone 2AX phosphorylation coincided with terminal deoxynucleotidyl transferase dUTP nick end labeling positive cells and pyknotic nuclei, suggesting caspase‐independent mechanisms on nuclei/DNA. Large DNA fragments, but not 180 bp fragmentation ladders, were observed, suggesting incomplete apoptosis. Nevertheless, tumor weight and volume decreased and tumors disappeared. One week after treatment, vessel numbers, vascular endothelial growth factor (VEGF), platelet derived endothelial cell growth factor (PD‐ECGF), CD31, CD35 and CD105 were decreased, indicating anti‐angiogenesis. The nsPEFs activate multiple melanoma therapeutic targets, which is consistent with successes of nsPEF applications for tumor treatment in vivo as a new cancer therapeutic modality.


Biochemical and Biophysical Research Communications | 2007

Ultrashort electric pulse induced changes in cellular dielectric properties

Allen L. Garner; George Chen; Nianyong Chen; V. Sridhara; Juergen F. Kolb; R. James Swanson; Stephen J. Beebe; R. P. Joshi; Karl H. Schoenbach

The interaction of nanosecond duration pulsed electric fields (nsPEFs) with biological cells, and the models describing this behavior, depend critically on the electrical properties of the cells being pulsed. Here, we used time domain dielectric spectroscopy to measure the dielectric properties of Jurkat cells, a malignant human T-cell line, before and after exposure to five 10ns, 150kV/cm electrical pulses. The cytoplasm and nucleoplasm conductivities decreased dramatically following pulsing, corresponding to previously observed rises in cell suspension conductivity. This suggests that electropermeabilization occurred, resulting in ion transport from the cells interior to the exterior. A delayed decrease in cell membrane conductivity after the nsPEFs possibly suggests long-term ion channel damage or use dependence due to repeated membrane charging and discharging. This data could be used in models describing the phenomena at work.


PLOS ONE | 2013

Age-associated metabolic and morphologic changes in mitochondria of individual mouse and hamster oocytes.

Fatma Simsek-Duran; Fang Li; Wentia Ford; R. James Swanson; Howard W. Jones; Frank J. Castora

Background In human oocytes, as in other mammalian ova, there is a significant variation in the pregnancy potential, with approximately 20% of oocyte-sperm meetings resulting in pregnancies. This frequency of successful fertilization decreases as the oocytes age. This low proportion of fruitful couplings appears to be influenced by changes in mitochondrial structure and function. In this study, we have examined mitochondrial biogenesis in both hamster (Mesocricetus auratus ) and mouse (Mus musculus) ova as models for understanding the effects of aging on mitochondrial structure and energy production within the mammalian oocyte. Methodology/Principal Findings Individual metaphase II oocytes from a total of 25 young and old mice and hamsters were collected from ovarian follicles after hormone stimulation and prepared for biochemical or structural analysis. Adenosine triphosphate levels and mitochondrial DNA number were determined within individual oocytes from young and old animals. In aged hamsters, oocyte adenosine triphosphate levels and mitochondrial DNA molecules were reduced 35.4% and 51.8%, respectively. Reductions of 38.4% and 44% in adenosine triphosphate and mitochondrial genomes, respectively, were also seen in aged mouse oocytes. Transmission electron microscopic (TEM) analysis showed that aged rodent oocytes had significant alterations in mitochondrial and cytoplasmic lamellae structure. Conclusions/Significance In both mice and hamsters, decreased adenosine triphosphate in aged oocytes is correlated with a similar decrease in mtDNA molecules and number of mitochondria. Mitochondria in mice and hamsters undergo significant morphological change with aging including mitochondrial vacuolization, cristae alterations, and changes in cytoplasmic lamellae.


Biology of Reproduction | 2002

In Vivo Effect of Leukemia Inhibitory Factor (LIF) and an Anti-LIF Polyclonal Antibody on Murine Embryo and Fetal Development Following Exposure at the Time of Transcervical Blastocyst Transfer

Michael H. Mitchell; R. James Swanson; Sergio Oehninger

Abstract Leukemia inhibitory factor (LIF) enhances in vitro murine preimplantation development in a time- and dose-dependent fashion. Knockout experiments have demonstrated that endometrial LIF is essential for in vivo murine implantation. We assessed the impact of LIF and an anti-LIF polyclonal antibody (pab) on in vivo development and developed a novel and successful nonsurgical method of embryo transfer for this species, a transcervical blastocyst transfer technique. The objectives of this study were to evaluate the effects of LIF and the anti-LIF pab on 1) implantation, resorption, pregnancy, and viability rates and 2) the overall structural and skeletal development. Two-cell embryos were recovered from superovulated mated donors, cultured to the expanded blastocyst stage, and transferred transcervically into pseudopregnant recipients. Exposure to 5000 U/ml LIF resulted in significant increases in implantation, pregnancy, and viability rates compared with controls. A similar dose of pab produced overall inhibitory effects with a significant decrease in implantation rate. Paradoxically, lower pab doses resulted in significantly increased viability rates. Exposure to LIF had no effect on fetoplacental development. However, pab treatments had variable but significant negative effects on placental length, ossification of the exoccipital bone, and vertebral space width compared with controls. Exposure of murine blastocysts to LIF at the time of transcervical transfer resulted in pronounced positive effects on implantation and pregnancy rates without affecting fetal development. A similar pab dose dramatically reduced implantation and pregnancy rates; at high and low doses, pab produced deleterious effects on placental and skeletal development.


Melanoma Research | 2009

Histopathology of normal skin and melanomas after nanosecond pulsed electric field treatment

Xinhua Chen; R. James Swanson; Juergen F. Kolb; Richard Nuccitelli; Karl H. Schoenbach

Nanosecond pulsed electric fields (nsPEFs) can affect the intracellular structures of cells in vitro. This study shows the direct effects of nsPEFs on tumor growth, tumor volume, and histological characteristics of normal skin and B16-F10 melanoma in SKH-1 mice. A melanoma model was set up by injecting B16-F10 into female SKH-1 mice. After a 100-pulse treatment with an nsPEF (40-kV/cm field strength; 300-ns duration; 30-ns rise time; 2-Hz repetition rate), tumor growth and histology were studied using transillumination, light microscopy with hematoxylin and eosin stain and transmission electron microscopy. Melanin and iron within the melanoma tumor were also detected with specific stains. After nsPEF treatment, tumor development was inhibited with decreased volumes post-nsPEF treatment compared with control tumors (P<0.05). The nsPEF-treated tumor volume was reduced significantly compared with the control group (P<0.01). Hematoxylin and eosin stain and transmission electron microscopy showed morphological changes and nuclear shrinkage in the tumor. Fontana–Masson stain indicates that nsPEF can externalize the melanin. Iron stain suggested nsPEF caused slight hemorrhage in the treated tissue. Histology confirmed that repeated applications of nsPEF disrupted the vascular network. nsPEF treatment can significantly disrupt the vasculature, reduce subcutaneous murine melanoma development, and produce tumor cell contraction and nuclear shrinkage while concurrently, but not permanently, damaging peripheral healthy skin tissue in the treated area, which we attribute to the highly localized electric fields surrounding the needle electrodes.


American Journal of Reproductive Immunology | 1981

An Indirect Enzyme‐Linked Immunosorbent Assay (ELISA) for the Detection and Quantitation of Antisperm Antibodies

Steven B. Ackekman; J. W. E. Wortham; R. James Swanson

ABSTRACT: Several recent comparative investigations using various assays to detect and quantitate levels of antibody to human spermatozoa have produced widely varying results. In an attempt to reduce test variability, an indirect enzyme‐linked immunosorbent assay (ELISA) was devised to measure antisperm antibodies. A standardized protocol was adapted employing sperm adsorption to polystyrene microtiter plates, at a density of 105 sperm per well, serum and enzyme‐conjugate incubation conditions at 37°C for 60 min, and three ten‐minute washes between incubations using phosphate‐buffered saline containing Tween‐20. Using antihuman sperm antisera generated in rabbits, the ELISA was shown to yield significantly detectable antibody at dilutions of 1/16,384. The ELISA demonstrated approximately 89% reproducibility (ie, 100% minus the coefficient of variation) for an “intraassay” study wherein 300 determinations were performed on the same day on sperm from ten donors. However, when sperm from one donor were used in 30 determinations during ten assays over a six‐month period, “interassay” reproducibility was approximately 51%. The ELISA was compared with macroagglutination, microagglutination, and immobilization tests, using rabbit antisperm serum and human sera from vasectomized males. Results of this study indicated that the ELISA was more sensitive, less subjective, and easier to perform than these other commonly used techniques.


Journal of Dermatological Treatment | 2011

Histopathological follow-up by tissue micro-array in a survival study after melanoma treated by nanosecond pulsed electric fields (nsPEF)

Xinhua Chen; Xinmei Chen; R. James Swanson; Karl H. Schoenbach; Shengyong Yin; Shusen Zheng

Abstract A recent study has shown that nanosecond pulsed electric fields (nsPEF) can affect the intracellular structures of melanoma within weeks. nsPEF is a non-drug, non-thermal treatment using ultrashort, intense pulsed electric fields with nanosecond durations. In the current study we followed up melanoma histopathology and metastasis with tissue micro-array 5 months post-nsPEF. After nsPEF treatment, tumor growth, tumor histology, metastasis, peri-tumor vessel and micro-vessel density were examined for the effect of nsPEF treatment on melanoma in vivo. The 17 nsPEF-treated mice were tumor-free for 169 days, significantly longer than those 19 control mice bearing melanoma without nsPEF. Histopathology follow-up showed that melanoma did not recur to the primary injection place after complete elimination. Compared with the control tumor, nsPEF-treated tumors present decreased micro-vessel density in a time-course manner in this survival study. Treatment with nsPEF caused continuous histopathological changes in melanomas, eliminated melanoma without recurrence at the primary site and prolonged animal survival time by inhibiting tumor blood supply and leading to tumor infarction. Thus, nsPEF could be applied in a non-ionizing therapeutic approach, without other agents, to locally treat tumors within a defined boundary.


Oncotarget | 2017

Nano-pulse stimulation (NPS) ablate tumors and inhibit lung metastasis on both canine spontaneous osteosarcoma and murine transplanted hepatocellular carcinoma with high metastatic potential

Xinhua Chen; Yiling Chen; Jianwen Jiang; Liming Wu; Shengyong Yin; Xudong Miao; R. James Swanson; Shusen Zheng

Background Nanosecond pulsed electric field (nsPEF), which is also termed as nano-pulse stimulation (NPS), has the potential of stimulating immune responses toward cancer cells. The current study investigates its local and systemic antitumor efficacy in vivo in late stage tumors with lung metastasis. Method The 12 canines with spontaneous osteosarcomas and 12 nude mice transplanted with human hepatocellular carcinoma were divided randomly and were given NPS treatment, surgery or no treatment control. Nanosecond pulsed electric field was delivered with puncture electrodes at 40 kV/cm with 500 pulses at 1 Hz. The survival time, tumor volume, serum alkaline phosphatase (ALP), joint capsule damage and lung metastasis were followed up. The efficacy was compared with control. Results Nanosecond pulsed electric field reduced primary tumor volume and extended the survival significantly compared to the control group (P<0.05). Inhibition of serum alkaline phosphatase and lung metastasis without joint deformity or thermal damage were also observed. Conclusion Locally applied nanosecond pulsed electric field is a novel non-thermal ablation method. It can ablate the primary tumor and decrease lung metastasis as a palliative therapy for late stage tumor.

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Xinhua Chen

Old Dominion University

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R. P. Joshi

Old Dominion University

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Sergio Oehninger

Eastern Virginia Medical School

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