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L Carson

Publications and source records attributed to L Carson.

At least 37 records · Page 2Linked to original sources
PubMed1994

How accurate is the pelvic examination as compared to transvaginal sonography? A prospective, comparative study.

Findings at pelvic examination in 120 patients were compared to those obtained by transvaginal sonography (TVS). Overall, 102 of 472 (22%) pelvic examination assessments did not agree with the TVS findings. Twenty-nine (36%) uterine assessments differed, while 46 (32%) ovarian assessments differed. Among 37 pelvic masses assessed in 20 cases (54%) the pelvic examination differed from the findings obtained by TVS. Only 4 (29%) cases assessed by pelvic examination were in agreement with the laparotomy findings as compared with 10 (71%) cases assessed by TVS.

Adolescent↗
PubMed1994

Flow characteristics in benign and malignant gynecologic tumors using transvaginal color flow Doppler.

OBJECTIVE: To assess flow characteristics of benign and malignant gynecologic tumors by transvaginal color flow Doppler. METHODS: Records of the Ultrasound Laboratory, Women's Cancer Center, University of Minnesota were analyzed retrospectively. Gray scale findings were recorded as either "diagnostic" or "nondiagnostic." Color flow assessment was performed on intratumor vessels or ovarian and/or uterine arteries. Flow was recorded as either "absent" or "present." Spectral analysis allowed determination of the systolic, diastolic, and mean velocities and calculation of the pulsatility and resistance indices. Malignancy was then predicted based upon color flow findings alone, with malignant tumors demonstrating increased color flow and a pulsatility index of at most 1.0 or a resistance index of at most 0.4. Color flow Doppler findings were then recorded as "giving additional useful information" that either confirmed questionable gray scale findings or changed the gray scale sonographic diagnosis, or as "not giving additional information" over the gray scale diagnosis. RESULTS: Two hundred thirty-one patients had gray scale sonography, and 167 also had color flow Doppler performed. Gray scale sonographic findings were sufficient to make a diagnosis in 156 (93%) of the scans. Color flow Doppler findings added useful information in 49 scans (30%). Increased color flow was highly significant (P < .0001), as was the calculated pulsatility index (P < .02) and resistance index (P < .008), in distinguishing benign from malignant tumors. Ovarian and uterine artery and intratumor assessments of the systolic, diastolic, and mean velocities were not significantly different between the benign and malignant tumors. Regression analysis confirmed the presence or absence of color flow as an independent predictor of malignancy or benignity (P < .0001). CONCLUSIONS: Our large study confirms the overall accuracy of gray scale scanning. When used alone, color flow Doppler--although specific--lacks sensitivity and predictive value as an independent predictor of malignancy. When findings were combined with those obtained from gray scale scanning, sensitivity, specificity, and predictive value were improved to acceptable levels. Significant differences existed between benign and malignant tumors for calculated pulsatility index and resistance index, but neither was sufficiently sensitive, specific, or predictive to be used alone as sole criteria of malignancy prediction. Other flow indices studied (systolic, diastolic, and mean velocities) in general did not differ significantly between groups. Physicians should be cautioned against using color flow findings alone for clinical decision making. We recommend a multi-institutional study to investigate the multiple vascular assessments to determine the role of color flow Doppler in the preoperative prediction of pelvic tumors and in screening for gynecologic abnormality.

Adult↗
PubMed1993

Invasive vulvar tumors in young women--a disease of the immunosuppressed?

Twenty-seven patients under the age of 40 years were treated for invasive vulvar cancer at the Women's Cancer Center, University of Minnesota. Seventeen patients had Stage I, five patients had Stage II, two patients had Stage III, and two patients had Stage IV disease. Twenty patients (80%) gave a history of smoking. Associated medical and immunosuppressive conditions present in these patients included vulval HPV (N = 3), diabetes mellitus (N = 3), pregnancy (N = 2), autoimmune connective tissue disease (N = 2), renal transplant (N = 2), previous chemotherapy for invasive malignancies at other sites (N = 1), chronic hepatitis (N = 1), schizophrenia (N = 1), and one patient on Imuran for herpes zoster and multiple sclerosis. Two of the nonsmokers were in this group of immunosuppressed patients. Three patients have died of intercurrent disease while another is currently alive with invasive disease. All others are alive without evidence of disease. The mean duration of follow-up is 45.2 months (range, 1-158 months). Invasive vulvar tumors are uncommon in young women. Smoking and a history of an immunosuppressive medical illness is common in this patient population.

Adult↗
PubMed1993

Persistent postmolar gestational trophoblastic disease: use of transvaginal sonography and colour flow Doppler.

Invasive moles have been difficult to diagnose except at hysterectomy. Many patients with persistent gestational trophoblastic disease (GTD) have been treated without ever demonstrating the site of the persistent trophoblastic focus. High resolution transvaginal sonography (TVS) has provided a technique of demonstrating very small uterine lesions, previously unsuspected by transabdominal sonography. The addition of colour flow Doppler further increased diagnostic sensitivity and provides another means of monitoring response to therapy. Three patients with persistent GTD, scanned by TVS and CFD (colour flow Doppler) performed as part of their metastatic work-up are presented. The only abnormalities detected were foci demonstrated within the myometrium that demonstrated increased flow on CFD. Single agent chemotherapy was commenced and the patients were monitored periodically through their course with repeat ultrasonography. After an initial lag period, the lesions decreased in size as the beta-HCG titres fell. An unsuspected adnexal mass was diagnosed on 1 patient, later proving to be a mature ovarian teratoma.

Adult↗
PubMed1993

Transvaginal color flow Doppler sonography in the assessment of gestational trophoblastic disease.

The aim of this study was to evaluate the blood flow characteristics of the uterine artery and intratumoral vessels in patients with GTD. Twelve patients with GTD were evaluated with TVS, and 11 also had CFD sonography performed. Spectral analysis of both uterine artery and samples intratumoral and intramyometrial vessels revealed systolic frequencies and PI that were significantly higher in the uterine artery than in sampled intratumoral vessels (P < 0.05). Uterine artery PI correlated significantly with age (P = 0.043), uterine size (P = 0.003), and beta-HCG titer (P = 0.03). Intratumoral PI correlated significantly with uterine size (P = 0.05). Intratumoral PI did not correlate with patient age, the shape or orientation of the uterus, presence or absence of subendometrial halo, endometrial thickness or echogenicity, or impression of myometrial invasion. Regression analysis of beta-HCG titers on uterine artery and intratumoral PI revealed a linear association. TVS and color flow Doppler sonography are useful in the assessment of patients with GTD. The PI is strongly associated with prognosis and correlates with beta-HCG titers.

Adult↗
PubMed1993

Borderline and invasive epithelial ovarian tumors in young women.

OBJECTIVE: To review the occurrence, morbidity, and mortality of borderline and invasive epithelial ovarian tumors in young women. METHODS: We conducted a 15-year retrospective review of the case records of the Women's Cancer Center, University of Minnesota, and the JL McKelvey Tumor Registry. RESULTS: We identified 67 patients under age 40 with borderline or invasive epithelial ovarian tumors. Fifty patients (75%) had borderline tumors and 17 (25%) had invasive tumors. The mean age at presentation was 31 years (range 14-39) for the borderline group and 34 years (range 23-39) for the invasive group. Pelvic pain and a palpable mass, present for less than 6 months, were the predominant presenting symptom and sign. There was no difference in the age at menarche between the patients with borderline (mean 12 years) and invasive tumors (mean 13 years). Fifty-seven patients were optimally cytoreduced to less than 2.0 cm after primary surgery. Thirty-five patients underwent second-look laparotomy, 15 of which were positive for tumor. A minority of patients in both groups had stage I tumors (17 in the borderline and one in the invasive group). Among patients with borderline tumors, there was no difference between "very young" and "young" patients in the stage at presentation or outcome. Similar proportions of patients presented with early- and late-stage disease. Three very young women (14%) and five young women (17%) have died. Among patients with invasive tumors, no difference existed between young and very young patients for stage at presentation, whereas grade and outcome differed significantly between the age groups (P < .05). Very young patients were more likely to present with grade 1 lesions, whereas patients aged 30-40 years were more likely to have grade 2 or 3 tumors (P < .05). Three (100%) of the very young patients have died, whereas seven (50%) of the young patients aged 30-40 years have died. The median survival of patients with borderline tumors was 36 months (range 2.0-150.5), significantly different from those with invasive tumors, whose median survival was 21 months (range 2.9-89.7) (P < .001). CONCLUSION: Borderline and invasive epithelial ovarian tumors are encountered in young women. Despite the implication of the term "borderline," such tumors are associated with considerable morbidity and mortality.

Adolescent↗
PubMed1991

Development of two new monoclonal antibodies reactive to a surface antigen present on human ovarian epithelial cancer cells.

Monoclonal antibodies which bind selectively to cancer cells are currently used for tumor localization and for targeting cytotoxic reagents. The success of these approaches depends on the specificity of the antibody and its reactivity to a majority of the tumor samples. Frequently, monoclonal antibodies are generated by immunizing mice with antigenic preparations from a single tumor cell line. Antibodies generated under these conditions often react to a narrow range of tumors. In the present study, mice were immunized with multiple ovarian cancer cell lines in a sequential manner to amplify the immune response against common antigenic determinants expressed in these cell lines. Spleen cells from the immunized mice were then fused with NS-1 myeloma cells to establish hybridomas. Two cell lines were selected on the basis of their selective reactivity to ovarian cancer cells after extensive screening. Monoclonal antibodies OVX1 and OVX2 bound to all 5 ovarian carcinoma cell lines tested and did not bind to normal fibroblast cells. These antibodies recognized a unique antigenic determinant present in ovarian and breast cancer cells. Cross-blocking studies showed that the binding of OVX1 and OVX2 is not displaceable by 10 other previously described anti-ovarian antibodies including OC125. In immunocytochemical studies, OVX1 reacted to a majority of ovarian cancer tissues (17 of 20) and did not bind to normal ovarian tissues. Preliminary results indicate that OVX1 and OVX2 antibodies are directed to a high molecular weight antigen. These antibodies could be used in the preparation of cytotoxic conjugates.

Animals↗
PubMed1991

Comparison of microbiologic assay methods for hemodialysis fluids.

To help prevent pyrogenic reactions and bacteremia in hemodialysis patients, the Association for the Advancement of Medical Instrumentation and the Centers for Disease Control recommend microbiologic assay of hemodialysis fluids at least monthly. Five commercially available assay systems were evaluated by using the membrane filtration technique with standard methods agar and trypticase soy agar as the standards for comparison. Each assay system was challenged with dialysate and reverse-osmosis water from local dialysis centers, aqueous suspensions of eight laboratory strains of gram-negative bacilli and nontuberculous mycobacteria, and a mixed microbial flora inoculated into reverse-osmosis water and laboratory-prepared dialysate. Mean viable counts from triplicate samples were obtained after incubation at 37 degrees C for up to 72 h. The efficiency of recovery varied with the specific type of microbial challenge. The SPC water sampler (Millipore Corp., Bedford, Mass.) was the most consistent in obtaining the highest viable counts. Other commercial systems were comparable to each other in overall performance. All assay systems tested provided an acceptable balance between microbial recovery and required sampling time, equipment, and expertise.

Bacteria↗
PubMed1990

Mechanism of potentiation of antithrombin III and heparin cofactor II inhibition by sulfated xylans.

Kinetic analyses of antithrombin III (AT-III)-thrombin or heparin cofactor II (HC-II)-thrombin or AT-III-factor Xa interactions were carried out in the absence or in the presence of one of the sulfated xylans or unfractionated heparin or low molecular weight (LMW) heparin utilizing chromogenic substrates. These studies demonstrated that under pseudo first order conditions the inhibitions were proportional to the AT-III or HC-II concentrations used and the apparent second order rate constants determined from the slopes of the pseudo first order plots of log of thrombin or Xa remaining as a function of time were significantly elevated in presence of the sulfated compounds. On a molar basis oat spelts xylan sulfate was the most effective compound in accelerating the rate of thrombin-AT-III interaction followed by commercial heparin while the latter was most effective in accelerating the rate of thrombin-HC-II interaction. Heparin and LMW heparin were more effective in that order in accelerating the rate of Xa-AT-III interaction while oat spelts xylan sulfate, corn cob xylan sulfate, SP-54 were less effective than the heparins in that order. Studies were also conducted on the concentrations of the sulfated compounds required to inhibit by 50% the thrombin activity by AT-III or HC-II or that required to inhibit by 50% the factor Xa activity by AT-III. The results showed an inverse relationship between the increase in the rate of acceleration by the sulfated compound with the decrease in the amount required for 50% inhibition. SDS-polyacrylamide gel study of the reaction mixture containing thrombin, AT-III or HC-II along with heparin or oat spelts xylan sulfate showed that like heparin, oat spelts xylan sulfate potentiated the formation of thrombin-AT-III or thrombin-HC-II complexes which were stable in presence of denaturing or reducing agents. Chemical modification of arginine or lysine of AT-III significantly lowered its potentiation of thrombin or Xa inhibition by oat spelts xylan sulfate.

Amino Acid Sequence↗
PubMed1989

Association of human immunodeficiency virus-induced immunosuppression with human papillomavirus infection and cervical intraepithelial neoplasia.

Human papillomavirus infection plays an important causal role in cervical intraepithelial neoplasia and carcinoma. The rate of infection with human papillomavirus as well as the incidence of cervical intraepithelial neoplasia and carcinoma are increased in immunosuppressed patients. We report a possible association between infection with human immunodeficiency virus and cervical intraepithelial neoplasia with human papillomavirus infection.

Acquired Immunodeficiency Syndrome↗