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Biomedical subjects

James Beck

Publications and source records attributed to James Beck.

8 recordsLinked to original sources
PubMed2003

Totally endoscopic atrial septal defect repair with robotic assistance.

BACKGROUND: Computer (robotic) enhancement had emerged as a facilitator of minimally invasive cardiac surgery, and has been used to perform portions of intracardiac procedures via thoracotomy incisions. This report describes the next step in this progression-the first U.S. application of robotic technology for totally endoscopic open heart surgery. METHODS AND RESULTS: Seventeen patients underwent repair of a secundum-type atrial septal defect (n=12) or patent foramen ovale (n=5) by a totally endoscopic approach, utilizing the Da Vinci robotic system. Cardiopulmonary bypass (CPB) was achieved peripherally. Cardioplegia was administered via the distal port of the arterial cannula after endo-balloon inflation. Via three port incisions in the right chest, pericardiotomy, bicaval occlusion, atriotomy, atrial septopexy, and atrial closure were performed by a surgeon seated at a computer console. A fourth 15-mm port was utilized for suction and suture passage by a patient-side assistant. The mean age of the patients was 47 years (range, 22 to 68). Aortic crossclamp time was 32 minutes (median), and CPB time was 122 minutes. In 16 patients, transesophageal echocardiography after 30 days confirmed successful repair. In one patient, a recurrent shunt was identified and repaired on postoperative day 5. Median length of stay (LOS) in the intensive care unit was 20 hours, and median hospital length of stay was 4 days. CONCLUSIONS: Robotic technology can be utilized to perform open heart procedures safely and effectively via totally endoscopic approaches. This technique represents an option for patients seeking a reliable ASD repair but wishing to avoid sternotomy or thoracotomy.

Adult↗
PubMed2003

Maternal periodontal disease is associated with an increased risk for preeclampsia.

OBJECTIVE: To determine if maternal periodontal disease is associated with the development of preeclampsia. METHODS: A cohort of 1,115 healthy pregnant women were enrolled at less than 26 weeks' gestation and followed until delivery. Maternal demographic and medical data were collected. Periodontal examinations were performed at enrollment and within 48 hours of delivery to determine the presence of severe periodontal disease or periodontal disease progression. Preeclampsia was defined as blood pressure greater than 140/90 on two separate occasions, and at least 1+ proteinuria on catheterized urine specimen. The potential effects of maternal age, race, smoking, gestational age at delivery, and insurance status were analyzed, and adjusted odds ratios for preeclampsia were calculated using multivariable logistic regression. RESULTS: During the study period, 763 women delivered live infants and had data available for analysis. Thirty-nine women had preeclampsia. Women were at higher risk for preeclampsia if they had severe periodontal disease at delivery (adjusted odds ratio 2.4, 95% confidence interval 1.1, 5.3), or if they had periodontal disease progression during pregnancy (adjusted odds ratio 2.1, 95% confidence interval 1.0, 4.4). CONCLUSION: After adjusting for other risk factors, active maternal periodontal disease during pregnancy is associated with an increased risk for the development of preeclampsia.

Adolescent↗
PubMed2003

Porphyromonas gingivalis infection during pregnancy increases maternal tumor necrosis factor alpha, suppresses maternal interleukin-10, and enhances fetal growth restriction and resorption in mice.

Epidemiological studies have shown a potential association between maternal periodontitis and pregnancy complications. We used a pregnant murine model to study the effect of infection with the periodontal pathogen Porphyromonas gingivalis on pregnancy outcomes. Female BALB/c mice were inoculated with heat-killed P. gingivalis (10(9) CFU) in a subcutaneous chamber and mated 2 weeks later. At gestation day (GD) 7.5, mice were challenged with live P. gingivalis (10(7) CFU) (n = 20) or broth (control; n = 8) and sacrificed at GD 16.5. Fetal growth restriction (FGR, <0.46 g) was defined as fetuses with weights 2 standard deviations (SD) smaller than controls (0.56 +/- 0.05 g [mean +/- SD]). Among the 20 challenged mice, 8 had both normal-weight (0.51 +/- 0.11 g) and FGR (0.34 +/- 0.1 g) fetuses within the same litter. All other challenged dams had normal-weight fetuses (0.57 +/- 0.04 g). Maternal liver, uterus, and spleen samples were examined for P. gingivalis DNA using a PCR technique. Of the eight challenged mice with FGR fetuses, three had PCR signals for P. gingivalis in liver and uterus, but not in the spleen. Liver, uterus, and spleen were negative for P. gingivalis DNA among all other challenged and control mice. In serum of dams with FGR fetuses, tumor necrosis factor alpha levels were elevated significantly, while interleukin-10 levels were significantly reduced compared to levels in dams with normal fetuses. P. gingivalis-specific serum immunoglobulin G levels were significantly elevated in dams with FGR fetuses compared to dams without any FGR fetuses. These data demonstrate that P. gingivalis-induced murine FGR is associated with systemic dissemination of the organism and activated maternal immune and inflammatory responses.

Animals↗
PubMed2003

Porphyromonas gingivalis infection in pregnant mice is associated with placental dissemination, an increase in the placental Th1/Th2 cytokine ratio, and fetal growth restriction.

Our previous animal studies showed that maternal Porphyromonas gingivalis infection in a subcutaneous chamber is associated with hepatic and uterine translocation, as well as systemic induction of maternal inflammatory responses, both of which were associated with fetal growth restriction (FGR). However, P. gingivalis-challenged dams had fetuses with either FGR (2 standard deviations below mean weight of nonchallenged dams) or normal weight. Therefore, the objective of this study was to determine whether maternal infection with P. gingivalis compromises normal fetal development via direct placental invasion and induction of fetus-specific placental immune responses characterized by a proinflammatory Th1-type cytokine profile. P. gingivalis-specific DNA was detected in placentas and fetuses of FGR and normal littermates from P. gingivalis-infected dams. Th1- and Th2-type cytokine mRNA as well as tumor necrosis factor alpha and transforming growth factor beta 2 mRNA were examined in placental tissue by using reverse transcription-PCR to determine Th1/Th2 ratios. For eight litters containing both normal-weight and FGR fetuses, P. gingivalis DNA was detected only in the placentas of FGR fetuses. All fetuses and all amniotic fluid samples from infected and control dams were negative for P. gingivalis DNA. mRNA levels of gamma interferon and interleukin-2 (IL-2) were significantly increased in placentas of FGR fetuses, while expression of IL-10 was significantly decreased in the same group. These data indicate that, in P. gingivalis-challenged dams, within each litter there is placenta-specific translocation of P. gingivalis that results in growth restriction of the targeted fetus, which is associated with a shift in the placental Th1/Th2 cytokine balance.

Animals↗
PubMed2002

Characterization of the biosynthetic gene cluster for the antifungal polyketide soraphen A from Sorangium cellulosum So ce26.

A genomic DNA region of over 80 kb that contains the complete biosynthetic gene cluster for the synthesis of the antifungal polyketide metabolite soraphen A was cloned from Sorangium cellulosum So ce26. The nucleotide sequence of the soraphen A gene region, including 67,523 bp was determined. Examination of this sequence led to the identification of two adjacent type I polyketide synthase (PKS) genes that encode the soraphen synthase. One of the soraphen A PKS genes includes three biosynthetic modules and the second contains five additional modules for a total of eight. The predicted substrate specificities of the acyltransferase (AT) domains, as well as the reductive loop domains identified within each module, are consistent with expectations from the structure of soraphen A. Genes were identified in the regions flanking the two soraphen synthase genes that are proposed to have roles in the biosynthesis of soraphen A. Downstream of the soraphen PKS genes is an O-methyltransferase (OMT) gene. Upstream of the soraphen PKS genes there is a gene encoding a reductase and a group of genes that are postulated to have roles in the synthesis of methoxymalonyl-acyl carrier protein (ACP). This unusual extender unit is proposed to be incorporated in two positions of the soraphen polyketide chain. One of the genes in this group contains distinct domains for an AT, an ACP, and an OMT.

Amino Acid Sequence↗
PubMed2002

Periodontal disease and cardiovascular disease: epidemiology and possible mechanisms.

BACKGROUND: Many early epidemiologic studies reported an association between periodontal disease and cardiovascular disease. However, other studies found no association or nonsignificant trends. This report summarizes the evidence from epidemiologic studies and studies that focused on potential contributing mechanisms to provide a more complete picture of the association between periodontal and heart disease. TYPES OF STUDIES REVIEWED: The authors summarize the longitudinal studies reported to date, because they represent the highest level of evidence available regarding the connection between periodontal disease and heart disease. The authors also review many of the case-control and cross-sectional studies published, as well as findings from clinical, animal and basic laboratory studies. RESULTS: The evidence suggests a moderate association--but not a causal relationship--between periodontal disease and heart disease. Results of some case-control studies indicate that subgingival periodontal pathogenic infection may be associated with myocardial infarction. Basic laboratory studies point to the biological plausibility of this association, since oral bacteria have been found in carotid atheromas and some oral bacteria may be associated with platelet aggregation, an event important for thrombosis. Animal studies have shown that atheroma formation can be enhanced by exposure to periodontal pathogens. CONCLUSIONS: The accumulation of epidemiologic, in vitro, clinical and animal evidence suggests that periodontal infection may be a contributing risk factor for heart disease. However, legitimate concerns have arisen about the nature of this relationship. These are early investigations. Since even a moderate risk contributed by periodontal disease to heart disease could contribute to significant morbidity and mortality, it is imperative that further studies be conducted to evaluate this relationship. One particularly important study to be carried out is the investigation of a possible clinically meaningful reduction in heart disease resulting from the prevention or treatment of periodontal disease.

Acute-Phase Reaction↗
PubMed2002

Totally endoscopic atrial septal defect repair with robotic assistance.

BACKGROUND: The development of minimally invasive cardiac surgery has been characterized by the performance of increasingly complex operations through progressively smaller incisions. Computer (robotic) enhancement has emerged as a potential facilitator of these procedures, initially by providing enhanced endoscopic camera control and, more recently, by allowing the manipulation of surgical instruments through limited thoracic incisions. This report describes the next step in this progression, namely the performance of an atrial septal defect (ASD) repair entirely through thoracoscopic port incisions. This represents the first U.S. application of robotic technology for totally endoscopic open-heart surgery. MATERIALS AND METHODS: A 33-year-old woman with a secundum atrial septal defect underwent totally endoscopic repair through four port incisions by means of the Da Vinci (Intuitive Surgical, Mountain View, CA) robotic surgical system. Cardiopulmonary bypass was achieved peripherally (femoral Estech endoaortic balloon cannula; femoral and right internal jugular venous Bio-medicus cannulae). The myocardium was protected with antegrade cold blood cardioplegia delivered through the distal port of the arterial cannula. After port insertion, the entire operation, including pericardiotomy, bicaval occlusion, atriotomy, atrial septopexy, and atrial closure, was performed by computer-aided control of a camera and two instrument arms manipulated by a surgeon seated 15 feet away. The fourth port was used for suction and suture passage by the patient-side assistant. The aortic cross-clamp time was 43 minutes, and the postoperative transesophageal echocardiogram demonstrated normal ventricular function and the absence of interatrial shunting. The patient was extubated on the night of surgery, was ambulatory within 15 hours, and was discharged on the morning of postoperative day 3, 63 hours after the procedure. At 30-day follow-up, the patient was well and without complaints, and transthoracic echocardiogram confirmed the continued absence of interatrial shunting. CONCLUSIONS: Computer-aided robotic surgical technology can be used to perform open-heart procedures with a totally endoscopic approach. The benefits of this approach may include decreased perioperative pain, decreased recovery times, and improved cosmesis and patient acceptance. Clinical trials currently in progress will demonstrate whether this technology will be of reproducible value in the management of patients with intracardiac disease on a larger scale.

Adult↗