Biomedical subjects
Publications and source records attributed to B Anderson.
We have measured the transverse asymmetry A(T') in 3He(e,e(')) quasielastic scattering in Hall A at Jefferson Laboratory with high precision for Q2 values from 0.1 to 0.6 (GeV/c)(2). The neutron magnetic form factor G(n)(M) was extracted based on Faddeev calculations for Q2 = 0.1 and 0.2 (GeV/c)(2) with an experimental uncertainty of less than 2%.
BACKGROUND: Traditional inguinal lymphadenectomy includes the removal of a portion of the saphenous vein. The authors hypothesized that preserving the saphenous vein would decrease morbidity without affecting treatment outcome. METHODS: A retrospective review of 83 patients with carcinoma of the vulva who underwent inguinal lymphadenectomy between 1990-1998 was performed. Postoperative short term and long term complications were evaluated. RESULTS: A total of 139 inguinal dissections were performed in 83 patients. The saphenous vein was preserved in 62 patients and ligated in 77 patients. The clinical characteristics of the patients, the operating time, and the estimated blood loss were not significantly different between the two groups. The incidence rate of short term complications including fever, seroma, phlebitis, lymphocyst, and deep venous thrombosis also was similar. Cellulitis occurred in 39% of the patients who underwent vein ligation compared with 18% of the patients who underwent a vein-sparing procedure (P = 0.006). Short term (< 6 months) lower extremity lymphedema occurred in 70% of the vein-ligated group compared with 32% of the vein-spared group (P < 0. 001). Chronic edema (>/= 2 years) was present in only 3% of the patients who underwent saphenous vein preservation compared with 32% of those who underwent vein ligation (P = 0.003). Chronic lymphedema in the vein-spared group was observed in only one patient who received postoperative radiation. Overall, individuals with preservation of the saphenous vein were less likely to develop complications (56% vs. 23%; P < 0.001). There was no difference in the rate of incidence of recurrent disease between the two groups. CONCLUSIONS: Preservation of the saphenous vein during inguinal lymphadenectomy reduces both the short term and long term postoperative complications without affecting treatment outcome. The saphenous vein should be preserved routinely in patients undergoing inguinal lymphadenectomy.
BACKGROUND: Quality of life (QOL) and mood were investigated among women who had received intensive chemotherapy for at least 1 year for advanced gynecologic cancers. Relationships of coping styles to QOL and mood in these patients also were examined. METHODS: Twenty-four patients who had been receiving chemotherapy continuously or intermittently for at least 1 year were recruited into the study. To control for the diagnosis of cancer and for prior hysterectomy, 24 age-matched early stage gynecologic cancer patients not receiving chemotherapy and assessed 1 year following diagnosis were examined as a comparison group. All subjects completed psychosocial assessments at a clinic visit. Medical information was retrospectively abstracted from patient charts. RESULTS: Decrements in physical, emotional, and functional well-being were reported by extensively treated patients, whereas social well-being and satisfaction with the relationship between doctor and patient were close to the norms of the comparison group. Extensively treated patients reported more fatigue and less vigor, but their depression and anxiety did not differ from early stage patients. Almost all extensively treated patients reported that their treatment had been worthwhile. Patients using avoidant coping reported poorer physical and emotional well-being, along with greater anxiety, depression, fatigue, and total mood disturbance. Those using active coping reported better social well-being, better relationships with their doctors, and less overall distress. CONCLUSIONS: This study indicates that gynecologic oncology patients extensively treated with chemotherapy experienced substantial decrements to quality of life, and yet treatment still was considered worthwhile by a majority of patients. Avoidant coping may be a particular risk factor for poor QOL and greater distress.
OBJECTIVE: To determine reaction time (RT) and its variability, as a function of horizontal spatial position, in subjects with neglect. BACKGROUND: In neglect, performance is frequently reported a as mean and a decreased ability to perform the task inferred by comparison to control groups. Few studies have examined how consistency and optimal performance relate to spatial neglect. METHODS: Ten subjects with brain damage, five with and five without spatial neglect, were assessed on a RT task. Subjects responded by pushing a computer key to the onset of a white square appearing on a black screen. The locations of stimuli were randomly varied along the horizontal meridian. RESULTS: For three of five neglect subjects, optimal RT showed no or little relation to horizontal location. Four of five neglect subjects demonstrated an increased variability in RT that correlated with spatial position and which was not present in our brain damaged subjects without neglect. The relationship was not an artifact of left sided stimuli, in general, being processed differently. For the two neglect subjects with the most trials, a significant correlation between RT variability and spatial position existed for left-sided trials alone. Increased variability was not a consequence of simply looking left proportionately less often, nor could a model of multiple compensatory systems operating in parallel explain the enhanced variability. Neither hemianopsia alone nor brain damage per se could account for the spatial modulation of RT variability. CONCLUSIONS: That neglect subjects perform the RT task normally on some trials, even in their 'neglected field', challenges the notion that neglect must reflect an irreparably damaged cognitive system. Performance decrements in neglect can reflect an inability to consistently detect and respond. Evaluating optimal performance and variability of performance can indicate if a capacity has been lost absolutely or merely degraded such that normal performance cannot be sustained.
OBJECTIVE: To compare the prognoses of women diagnosed with cervical cancer during pregnancy with the prognoses of those diagnosed within 6 months after delivery and to assess the effect of vaginal delivery on recurrence risk and prognosis. METHODS: A matched case-control study of women with cervical cancer diagnosed during pregnancy or within 6 months of delivery was performed. Fifty-six women had cervical cancer diagnosed during pregnancy and 27 within 6 months after delivery. Controls (cervical cancer diagnosed at least 5 years since last delivery) were matched one-to-one with cases based on age, histology, stage, treatment, and time of treatment. RESULTS: Among postpartum women, four had stage IA disease, 15 had stage IB1 or IB2, and eight had stage IIA or higher disease. Eleven had radical hysterectomies and 14 had radiation therapy. Two with stage IA1 disease were treated with vaginal hysterectomies. One of seven patients who had cesareans developed a local and distant recurrence. In contrast, ten of 17 (59%) who delivered vaginally developed recurrences (P =.04). In multivariate analysis, vaginal delivery was the most significant predictor of recurrence (odds ratio [OR] 6.91; 95% confidence interval [CI] 1.45, 32.8), followed by high stage (OR 4.66; 95% CI 1.05, 20.8). The survival for patients diagnosed in the postpartum period was significantly worse than for controls. CONCLUSION: Women diagnosed postpartum had worse survival than those diagnosed during pregnancy and were at significant risk of recurrent disease, particularly if they delivered vaginally. Therefore, pregnant women with cervical cancer should be delivered by cesarean.
OBJECTIVE: To determine the value of computed tomography (CT) scans for preoperatively detecting extrauterine-nodal disease and postoperative recurrent disease in patients with endometrial cancer. METHODS: We reviewed records of 702 women with primary endometrial carcinoma that was diagnosed between 1979 and 1993. Preoperative CT findings were compared with pathologic findings to assess nodal disease. The yield of postoperative CT was reviewed in clinically suspicious and routine settings. RESULTS: Among 492 women eligible for analysis, 178 (36%) had a total 326 CT scans. Among 56 women who had preoperative CT scans and lymph node samplings, positive and negative predictive values for nodal involvement were 50% and 94%, respectively, and sensitivity and specificity were 57% and 92%, respectively. Preoperative CT findings altered treatment plans in only six patients (8%). Forty-five asymptomatic women had 73 routine CT scans, and recurrence was diagnosed by CT in only two (4.4%). Thirty-seven women had CT scans for suspicion of recurrence, which was confirmed in 17 (46%). Kaplan-Meyer analysis showed no survival advantage in women with subclinical recurrences diagnosed by CT scan. CONCLUSION: Routine preoperative CT scanning rarely alters treatment and is a poor predictor of nodal disease. Computed tomography in the postoperative period might be helpful for detection and follow-up of recurrent disease, but there was no difference in survival when subclinical recurrence was found by CT. Thus, CT scanning of any woman with endometrial cancer should be discouraged unless it is to evaluate symptoms.
The objective of this study was to investigate the vascular and biochemical effects of a formulated product in the form of a bar enriched with a combination of nutrients known to enhance the synthesis or activity of endothelium-derived nitric oxide (EDNO). Individuals with hypercholesterolemia manifest impaired flow-mediated vasodilation, which is largely due to a reduction in EDNO activity. Oral supplementation with large amounts (6-21 g/day) of L-arginine, the precursor of EDNO, have been shown to improve endothelium-mediated vasodilation in hypercholesterolemia. Such large doses are effective but may be impractical to take in capsule form. Accordingly, we have developed a nutrient bar enriched with L-arginine as well as other ingredients that additively enhance EDNO activity. A pilot study in 41 hypercholesterolemic individuals indicated that the bar was well tolerated, had no adverse effects on serum chemistries or lipid profile, and normalized endothelial vasodilator function. To definitively determine if the nutrient bar normalizes endothelial function, a double-blind, placebo-controlled study was performed. Flow-mediated endothelium-dependent vasodilation was assessed by high-resolution ultrasonography before and after 1 week of bar use (2 bars/day) in an additional group of 43 volunteer subjects (57 +/- 10 years old; 22 men, 21 women) with hypercholesterolemia. Subjects manifested an impaired flow-mediated vasodilation before the intervention. Vasodilator function in the active bar group improved to within a normal range (6.5 +/- 3% before to 10 +/- 5% after, P = 0.02; normal, 12 +/- 3%) and was significantly better (P < 0.01) than in the placebo bar group (7.1 +/- 3% before to 6.7 +/- 4% after). These findings reveal that use of a nutrient bar designed to enhance EDNO activity improves flow-mediated endothelium-dependent vasodilation in hypercholesterolemic individuals.
A common misconception is that bipolar disorder is an endogenous process. However, previous research suggests a role for life events in the onset of and recovery from bipolar episodes. Yet, there remains some question as to whether the relationship between life events and onset changes over the course of the disorder as a result of the number of episodes an individual has experienced. Using a rigorous interview measure of stressful life events, the current study tested the kindling model (R. M. Post, 1992), which theorizes that major life events play a diminishing role over the course of illness in bipolar patients. Analyses revealed that the number of episodes experienced does not appear to have a significant effect on bipolar 1 patients' reactivity to external stressors. In addition, the results suggest that a more complex relationship exists among age, stress, and onset of new episodes than can be adequately explained by the kindling model.
Adverse reactions with DMSO-cryopreserved stem cell infusion are well-recognized. However, severe, life-threatening anaphylactic reactions with DMSO are very rarely described in the literature. We report here a 58-year-old female with AL amyloidosis who developed an unexpected episode of respiratory arrest a few seconds after the beginning of thawed stem cell product infusion. Fortunately, the patient was resuscitated successfully without the need for intubation. The prompt development of the reaction just a few seconds after the stem cell infusion convincingly implicates DMSO as the potential suspect. The presence of amyloid cardiomyopathy might have also contributed to this adverse event. Bone Marrow Transplantation (2000) 25, 1299-1301.
OBJECTIVES: To determine the risk factors for acquisition of nosocomial primary bloodstream infections (BSIs), including the effect of nursing-staff levels, in surgical intensive care unit (SICU) patients. DESIGN: A nested case-control study. SETTING: A 20-bed SICU in a 1,000-bed inner-city public hospital. PATIENTS: 28 patients with BSI (case-patients) were compared to 99 randomly selected patients (controls) hospitalized > or =3 days in the same unit. RESULTS: Case- and control-patients were similar in age, severity of illness, and type of central venous catheter (CVC) used. Case-patients were significantly more likely than controls to be hospitalized during a 5-month period that had lower regular-nurse-to-patient and higher pool-nurse-to-patient ratios than during an 8-month reference period; to be in the SICU for a longer period of time; to be mechanically ventilated longer; to receive more antimicrobials and total parenteral nutrition; to have more CVC days; or to die. Case-patients had significantly lower regular-nurse-to-patient and higher pool-nurse-to-patient ratios for the 3 days before BSI than controls. In multivariate analyses, admission during a period of higher pool-nurse-to-patient ratio (odds ratio [OR]=3.8), total parenteral nutrition (OR=1.3), and CVC days (OR=1.1) remained independent BSI risk factors. CONCLUSIONS: Our data suggest that, in addition to other factors, nurse staffing composition (ie, pool-nurse-to-patient ratio) may be related to primary BSI risk. Patterns in intensive care unit nurse staffing should be monitored to assess their impact on nosocomial infection rates. This may be particularly important in an era of cost containment and healthcare reform.
A 17-kDa, immunodominant antigen of Bartonella henselae Houston-1 has previously been cloned, sequenced, and characterized. This clone (H13) contains the 17-kDa antigen gene plus a partial open reading frame, designated ORF1, which is 459 nucleotides long and is directly upstream of the 17-kDa gene. Comparison of the deduced partial amino acid sequence of ORF1 with that of other known genes in GenBank revealed significant identity with several other bacterial virulence genes, including VirB4 of the Agrobacterium tumefaciens virB operon (56/149 amino acids). An overlapping clone, pGB3, was recovered and shown to contain a 3.0-kb region upstream of the 17-kDa gene. Sequence analysis revealed three ORFs upstream of the gene. The deduced amino acid sequence of each ORF was compared with sequences in GenBank, and identity was found with VirB2, VirB3, and VirB4 of A. tumefaciens. In vitro transcription/translation and SDS-PAGE demonstrated that three proteins of 9 kDa, 10 kDa, and 92 kDa, corresponding to the predicted molecular weight of 10.9 kDa, 11.7 kDa, and 89.9 kDa of VirB2, VirB3, and VirB4, respectively, could be expressed from these coding regions. These results indicate that virulence-associated genes and their overall chromosomal arrangement are relatively well conserved between B. henselae and other gram-negative bacteria such as A. tumefaciens.
Health-related quality of life instruments for cancer patients and specifically for gynecologic cancer patients have been developed, validated and applied in clinical trials. More focused investigations of specific symptoms, side-effects and both short- and long-term toxicities are also being pursued. Assessments are now included as part of many cancer treatment trials and some studies are looking at quality of life in survivors. Another area of investigation seeks to define the types of stress and coping mechanisms being used in order to identify predictors of psychologic distress.
The 17-kDa antigen of Bartonella henselae has previously been shown to elicit a strong humoral immune response in patients with cat scratch disease (CSD) and to be useful in screening human serum samples for CSD. In this study, PCR amplification of genes homologous to the 17-kDa antigen gene of B. henselae was performed using genomic DNAs from several species of Bartonella, including the currently recognized human pathogens. Amplicons of similar size were demonstrated using the following chromosomal DNA templates: B. henselae (two strains), B. quintana (two strains), B. elizabethae, B. clarridgeiae, B. vinsonii subsp. vinsonii, and B. vinsonii subsp. berkhoffii. No evidence of a B. bacilliformis homolog of the 17-kDa antigen gene was obtained using multiple primer pairs. DNA sequencing revealed open reading frames capable of coding for proteins with sizes similar to that of the 17-kDa antigen of B. henselae in all of the amplicons; however, extensive sequence divergence across the genus was noted. Cloning of the amplified products into pUC19 resulted in recombinants that directed synthesis of homologs of the 17-kDa protein. Immunoblot analysis using human sera from CSD cases demonstrated very little cross-reactivity among different species for this protein. In contrast, immunoblots using rabbit serum raised to the recombinant B. henselae antigen showed extensive cross-reactivity with the proteins of other Bartonella species. The data suggest that the use of the 17-kDa antigen as a serologic reagent may allow the development of more specific diagnostic assays. Furthermore, the nucleotide sequences from the various versions of the 17-kDa antigen gene should be useful for rapid identification of Bartonella at the species level.
Some inborn errors of metabolism due to deficiencies of soluble lysosomal enzymes cause global neurodegenerative disease. Representative examples include the infantile and late infantile forms of the ceroid lipofuscinoses (CLN1 or CLN2 deficiency, respectively) and mucopolysaccharidoses type VII (MPS VII), a deficiency of beta-glucuronidase. Treatment of the central nervous system component of these disorders will require widespread protein or enzyme replacement, either through dissemination of the protein or through dissemination of a gene encoding it. We hypothesize that transduction of brain microcapillary endothelium (BME) with recombinant viral vectors, with secretion of enzyme product basolaterally, could allow for widespread enzyme dissemination. To achieve this, viruses should be modified to target the BME. This requires (i) identification of a BME-resident target receptor, (ii) identification of motifs targeted to that molecule, (iii) the construction of modified viruses to allow for binding to the target receptor, and (iv) demonstrated transduction of receptor-expressing cells. In proof of principal experiments, we chose the human transferrin receptor (hTfR), a molecule found at high density on human BME. A nonamer phage display library was panned for motifs which could bind hTfR. Forty-three clones were sequenced, most of which contained an AKxxK/R, KxKxPK/R, or KxK motif. Ten peptides representative of the three motifs were cloned into the HI loop of adenovirus type 5 fiber. All motifs tested retained their ability to trimerize and bind transferrin receptor, and seven allowed for recombinant adenovirus production. Importantly, the fiber-modified viruses facilitated increased gene transfer (2- to 34-fold) to hTfR expressing cell lines and human brain microcapillary endothelia expressing high levels of endogenous receptor. Our data indicate that adenoviruses can be modified in the HI loop for expanded tropism to the hTfR.
Animals possess the attributes we label as 'intelligent' in humans. 'Insight' and 'reasoning' have been demonstrated in chimpanzees, monkeys, racoons, rats, mice, ravens and pigeons. In the rat, the animal species best characterized psychologically and neuroanatomically, reasoning ability correlates with other cognitive capacities and brain size. Other learning task paradigms tested on mice and rats have confirmed consistent individual differences, indicated a neuroanatomical network for learning, and shown the presence of genetic influences for cognitive ability. Animals offer an opportunity to test ideas about intelligence that cannot be performed on humans. Methylazoxymethanol (MAM) administered prenatally can arrest cortical cell division and produce a 'mentally retarded' microcephalic rat. This intellectual deficiency can be ameliorated by postnatal induction of dendritic arborization and synapse formation with naltrexone, suggesting the relevance of neuronal and synapse number for behavioural variation in rat g. Inbred mice lines differ in brain size and behaviour, permitting, through the use of recombinant inbred strains, the determination of genetic loci with quantitative effects on structure and function. Lastly, genetic contributions to g can be directly tested by modifying gene expression and determining the anatomical, physiological, and behavioural benefits.
Explore the source record for details and available documents.