PubMed Health⌕ Search

Biomedical subjects

C A Anderson

Publications and source records attributed to C A Anderson.

At least 19 recordsLinked to original sources
PubMed2006

Tumorigenicity assessments of Per.C6 cells and of an Ad5-vectored HIV-1 vaccine produced on this continuous cell line.

PER.C6, a cell line derived from human embryonic retinal cells transformed with the Adenovirus Type 5 (Ad5) E1A and E1B genes, is used to produce E1-deleted Ad5 vectors such as the MRKAd5 HIV-1 gag vaccine. While whole, live PER.C6 cells are capable of growing as tumours when transplanted subcutaneously into immunodeficient nude mice at a high dosage, the process for vaccine production includes filtration steps and other methods which effectively preclude contamination by intact viable substrate cells. However, because of the neoplastic nature of this cell line, we carried out a series of investigations to assess the tumorigenic risk posed by residuals from the cell substrate in a vaccine. To address concerns about transmission of oncogenic DNA, we demonstrated that purified PER.C6 cellular DNA does not induce tumours in newborn hamsters or nude mice. To address concerns about other potential residuals, including hypothetical adventitious tumour viruses, we demonstrated that a PER.C6 cell lysate and a MRKAd5 HIV-1 gag vaccine produced on PER.C6 cells do not induce tumours in newborn hamsters or newborn rats. These results, in conjunction with the wide panel of viral safety tests performed on these cells, support the safety of the PER.C6 as a cell substrate for vaccine production.

AIDS Vaccines↗
PubMed2004

Automated distal coronary bypass with a novel magnetic coupler (MVP system).

OBJECTIVE: We sought to assess the feasibility of performing sutureless distal coronary artery bypass anastomoses with a novel magnetic coupling device. METHODS: From May 2000 to April 2001, single-vessel side-to-side coronary artery bypass grafting on a beating heart was performed in 39 domestic white pigs (35-60 kg) without the use of mechanical stabilization, shunts, or perfusion bridges. Animals were divided into 2 groups. Seventeen pigs underwent right internal thoracic artery to right coronary artery bypass grafting through a median sternotomy (group 1) with a novel magnetic vascular positioning system (MVP system; Ventrica, Inc, Fremont, Calif). Twenty-two pigs underwent left internal thoracic artery to left anterior descending artery grafting with the MVP anastomotic device through a left anterior minithoracotomy (group 2). This system consists of 2 pairs of elliptical magnetic implants and a deployment device. One pair of magnets forms the anastomotic docking port within the graft; the other pair forms an identical anastomotic docking port within the target vessel. The anastomosis is created when the 2 docking ports magnetically couple. Anastomotic patency was evaluated by means of angiography during the first postoperative week and at 1 month. Histologic studies were performed at different time points as late as 6 months. RESULTS: Right internal thoracic artery to right coronary artery anastomoses and left internal thoracic artery to left anterior descending artery anastomoses were successfully performed with the system in all animals. The self-adherent and self-aligning properties of the implants allowed for immediate and secure approximation of the arteries (total anastomotic time between 2-3 minutes). Anastomoses were constructed without a stabilization platform. Five nondevice-related deaths occurred postoperatively. One-week angiography, performed in 35 surviving animals, showed a patent graft and anastomosis in all cases. The patency rate at 1 month was 97% (33/34). Histologic studies as late as 6 months demonstrated neointimal coverage of the magnets without any significant luminal obstruction. Histology also confirmed the presence of viable tissue between magnets. CONCLUSION: The MVP anastomotic system uses magnetic force to create rapid and secure distal coronary artery anastomoses, which might facilitate minimally invasive and totally endoscopic coronary artery bypass surgery.

Anastomosis, Surgical↗
PubMed2004

Anal condyloma: a comparison between HIV positive and negative patients.

HIV positive and negative patients with anal condylomata were compared to determine an association with squamous cell neoplasia, its disease progression, and response to treatment. From 1992 to 2003, 61 patients were diagnosed with anal condylomata by anal biopsy. Thirty-four patients were HIV+ and 27 patients were considered HIV-. Upon retrospective chart review, details on disease progression, development of malignancy, and subsequent treatment were collected. Sixty-one per cent of HIV+ patients had a neoplastic process in contrast to 25 per cent of HIV- patients (P = 0.005). Five patients demonstrated disease progression, of which four were HIV+. Three HIV+ patients were treated for invasive carcinoma with excision and standard chemoradiation therapy. Two patients with T3 lesions developed recurrence and died. Eighteen HIV+ patients had noninvasive carcinoma and were treated with local excision without recurrence at mean follow-up of 28 months. HIV+ patients were shown to have more condylomata harboring squamous cell neoplasia than HIV- patients. Noninvasive carcinoma can be treated effectively with local excision, independent of HIV status; however, long-term follow-up is needed. Chemoradiation therapy in patients who are relatively healthy and have stage I disease may be successful. The role for chemoradiation in AIDS patients with stage III disease remains unclear.

Adolescent↗
PubMed2001

Results of laparoscopically assisted colon resection for carcinoma.

BACKGROUND: Surgical resection is the primary treatment for colorectal carcinoma. Laparoscopically assisted colon resection technically is feasible for both benign and malignant disease. However, the role of laparoscopically assisted colon resection for carcinoma is controversial. METHODS: We prospectively studied our first 100 patients with colorectal carcinoma who successfully underwent laparoscopically assisted colon resection for the carcinoma. RESULTS: The pathologic stages were Dukes' categories A-16, B-52, C-25, and D-7. Operative mortality and morbidity were 2% and 22%, respectively. During a mean follow-up period of 40.3 months, recurrence by stage was zero patients with stage A disease, five patients with stage B disease, nine patients with stage C disease. Thirteen of these patients died as a result of their disease. At this writing, 60 patients are alive without evidence of disease, and 23 have completed the study disease free after more than 60 months. The 5-year survival probabilities by stage were 100% for stage A, 76.8% for stage B, and 51.7% for stage C. CONCLUSIONS: Laparoscopically assisted colectomy for cancer can be performed safely. The recurrence rate after laparoscopically assisted resection appears to be at least as good as after open resection. Results from ongoing prospective, randomized trials are needed to confirm these findings.

Adult↗
PubMed2001

A dissociation between symbolic number knowledge and analogue magnitude information.

Semantic understanding of numbers and related concepts can be dissociated from rote knowledge of arithmetic facts. However, distinctions among different kinds of semantic representations related to numbers have not been fully explored. Working with numbers and arithmetic requires representing semantic information that is both analogue (e.g., the approximate magnitude of a number) and symbolic (e.g., what / means). In this article, the authors describe a patient (MC) who exhibits a dissociation between tasks that require symbolic number knowledge (e.g., knowledge of arithmetic symbols including numbers, knowledge of concepts related to numbers such as rounding) and tasks that require an analogue magnitude representation (e.g., comparing size or frequency). MC is impaired on a variety of tasks that require symbolic number knowledge, but her ability to represent and process analogue magnitude information is intact. Her deficit in symbolic number knowledge extends to a variety of concepts related to numbers (e.g., decimal points, Roman numerals, what a quartet is) but not to any other semantic categories that we have tested. These findings suggest that symbolic number knowledge is a functionally independent component of the number processing system, that it is category specific, and that it is anatomically and functionally distinct from magnitude representations.

Aged↗
PubMed2001

Is it time to pull the plug on the hostile versus instrumental aggression dichotomy?

Psychologists have often categorized human aggression as hostile or instrumental. Hostile aggression is "hot," impulsive behavior that is motivated by a desire to hurt someone; instrumental aggression is "cold," premeditated behavior used as a means to some other end. This dichotomy was useful to the early development of aggression theories and continues to capture important features of nonhuman aggression, but it has outlived its usefulness as a descriptor of fundamentally different kinds of human aggression. It is confounded with the automatic-controlled information-processing dichotomy, and it fails to consider aggressive acts with multiple motives. Knowledge structure models of aggression easily handle these problems. Taking extreme measures to preserve the hostile-instrumental dichotomy will delay further advances in understanding and controlling human aggression. Therefore, this seems a proper time to "pull the plug" and allow the hostile-instrumental aggression dichotomy a dignified death.

Aggression↗
PubMed2001

Effects of violent video games on aggressive behavior, aggressive cognition, aggressive affect, physiological arousal, and prosocial behavior: a meta-analytic review of the scientific literature.

Research on exposure to television and movie violence suggests that playing violent video games will increase aggressive behavior. A metaanalytic review of the video-game research literature reveals that violent video games increase aggressive behavior in children and young adults. Experimental and nonexperimental studies with males and females in laboratory and field settings support this conclusion. Analyses also reveal that exposure to violent video games increases physiological arousal and aggression-related thoughts and feelings. Playing violent video games also decreases prosocial behavior.

Adolescent↗
PubMed2000

A specialist toxicity database (TRACE) is more effective than its larger, commercially available counterparts.

The retrieval precision and recall of a specialist bibliographic toxicity database (TRACE) and a range of widely available bibliographic databases used to identify toxicity papers were compared. The analysis indicated that the larger size and resources of the major bibliographic databases did not, for a series of test queries, assure superior retrieval of relevant papers. The specialist database, in which document selection and indexing is undertaken by the same expert toxicologists who use the database in their day-to-day work, achieved markedly better retrieval, using simpler search strategies, than the other databases. Specialist databases may offer a valuable alternative to the existing major bibliographic databases. The concept of relevance, as used to determine the effectiveness of bibliographic databases, is discussed.

Data Collection↗
PubMed2000

Video games and aggressive thoughts, feelings, and behavior in the laboratory and in life.

Two studies examined violent video game effects on aggression-related variables. Study 1 found that real-life violent video game play was positively related to aggressive behavior and delinquency. The relation was stronger for individuals who are characteristically aggressive and for men. Academic achievement was negatively related to overall amount of time spent playing video games. In Study 2, laboratory exposure to a graphically violent video game increased aggressive thoughts and behavior. In both studies, men had a more hostile view of the world than did women. The results from both studies are consistent with the General Affective Aggression Model, which predicts that exposure to violent video games will increase aggressive behavior in both the short term (e.g., laboratory aggression) and the long term (e.g., delinquency).

Adult↗
PubMed2000

Widespread countervailing genomic responses induced by chemotherapy or radiation as a cause of therapeutic failure.

If chemotherapy or ionizing radiation induce widespread genomic responses tending to circumvent or antagonize their ability to kill malignant cells, an additional cause for therapeutic failure would be suggested. There is evidence that some agents evoke extensive countervailing genomic activity, the nature and extent of which can be assessed with the use of 'gene chips'.

Antineoplastic Agents↗
PubMed2000

Seromuscular enteric pedicles and prosthetic aortic graft complications in a porcine abdominal trauma model. An experimental study.

BACKGROUND/AIMS: Abdominal vascular trauma may require prosthetic grafting despite peritoneal contamination by concurrent visceral injury. This study tested the use of vascularized, seromuscular enteric pedicles (VSEP) against the development of vascular prosthetic complications, in a porcine abdominal trauma model. METHODS: Eight pigs underwent aortic transection and reconstruction with a Dacron interposition graft (DIG). A standard bacterial inoculum soaked the DIG in situ. An enteric segment was isolated on its mesenteric pedicle, and the mucosa stripped. This VSEP was wrapped around the DIG and oversewn. Animals received antibiotics for 5 days. Endpoints were 2-week survival, or evidence of sepsis. The animals underwent explantation of the DIG, VSEP, and native aorta for the purposes of histological, and microbiological analyses, and scanning electron microscopy (SEM). Outcome measures were graft infection, graft thrombosis, tissue incorporation, and anastomotic integrity. RESULTS: Two pigs were excluded for perioperative death. All study group animals (n = 6), survived 2 weeks. Infection and thrombosis were found in 0/6 (0%). Incorporation and anastomotic integrity were evident in 6/6 (100%). VSEP had intact blood supplies. SEM demonstrated viable muscle, microcirculation, and fibroplasia in VSEP. CONCLUSION: We conclude that VSEP may help prevent prosthetic graft complications in the contaminated setting.

Abdominal Injuries↗
PubMed1999

One and one-half syndrome with supranuclear facial weakness: magnetic resonance imaging localization.

OBJECTIVE: To provide clinicoanatomical correlation for a small pontine tegmental ischemic stroke producing the one and one-half syndrome associated with supranuclear facial weakness. DESIGN: Case report. SETTING: Tertiary care center. PATIENT: A 70-year-old man developed left-sided facial weakness sparing the forehead, a left internuclear ophthalmoplegia, and a complete left horizontal gaze palsy immediately after percutaneous transluminal coronary angioplasty. Magnetic resonance imaging demonstrated a small lesion in the left paramedian aspect of the dorsal pontine tegmentum. MAIN OUTCOME AND RESULTS: Electromyographic findings were consistent with supranuclear facial involvement. The patient had nearly complete recovery after 1 year. CONCLUSIONS: To our knowledge, this is the first report of supranuclear facial weakness in association with the one and one-half syndrome. The location of the lesion provides evidence of the existence of corticofugal fibers that extend to the facial nucleus in the dorsal paramedian pontine tegmentum.

Aged↗
PubMed1998

Social evaluation influence on cardiovascular response to a fixed behavioral challenge: effects across a range of difficulty levels.

Participants performed five memory tasks--ranging in difficulty from very low to very high--under public or private conditions. The publicity and difficulty variables interacted to determine systolic pressure and heart rate responses during performance. Where performance was public, responsiveness on the parameters increased with difficulty to a point and then dropped; where performance was private, responsiveness was relatively low at all difficulty levels. Diastolic pressure responses were configured similarly, although in that case the interaction was not reliable. Findings corroborate and extend results from a previous study, argue against some explanations of those results, and strengthen the case for a recent active coping analysis of cardiovascular audience effects. Findings also strengthen the case for a broader model of effort and cardiovascular response, which has potential for advancing our understanding of a range of phenomena and processes related to behavior and health.

Adult↗
PubMed1998

Characterization of pneumococcal specific antibodies in healthy unvaccinated adults.

Unlike the elderly, healthy middle aged adults are at relatively low risk of acquiring serious pneumococcal disease. An explanation that has been proposed is that people in this age group have significant amounts of serum antibody (primarily IgG2) that react with any pneumococcal capsular polysaccharide serotypes. The level of antibody can be as high as several hundred micrograms per milliliter of blood for some serotypes. A significant component of this reactivity is directed toward the conserved C-polysaccharide depletion. Even after C-polysaccharide depletion, which is included as a routine part of the assay to determine antibody levels, resting antibody levels in a normal healthy adult population can vary widely. We have analyzed the reactivity of serum from 76 people to 16 pneumococcal capsular polysaccharide serotypes. The antibody reactivities to 13 of 16 serotypes are highly correlated with one another. Depletion of serum with C-polysaccharide and purified capsular polysaccharide inhibited antibody binding to type specific capsular polysaccharide. Cross-serotype inhibition of antibody binding was also observed. This indicates that there are materials contained within the pneumococcal polysaccharides that contribute to the cross-reactivity of serum antibodies in people that have not been vaccinated with the pneumococcal vaccine.

Adolescent↗