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Biomedical subjects

L A King

Publications and source records attributed to L A King.

At least 19 recordsLinked to original sources
PubMed1992

Assembly of functional GABAA receptors in insect cells using baculovirus expression vectors.

We have constructed recombinant baculoviruses containing cDNAs encoding either the alpha 1- or the beta 1-subunit of the bovine GABAA receptor. In Spodoptera frugiperda (IPLB-Sf-21) cells infected with recombinant virus expressing either the alpha 1- or beta 1-subunit, or in cells co-infected with both viruses, functional GABAA receptors were detected by whole-cell electrophysiological recordings. The threshold for the responses mediated by the homo-oligomeric channels (alpha- or beta-) was 2-3 x 10(-6) M GABA, and for the co-infected cells was 8 x 10(-8) M GABA, suggesting that hetero-oligomeric channels formed in these cells. All GABA-induced currents were found to be inhibited by bicuculline and picrotoxin, potentiated by pentobarbital but were insensitive to benzodiazepines.

Animals↗
PubMed1992

Characterization of two variants of Panolis flammea multiple nucleocapsid nuclear polyhedrosis virus.

The baculovirus Panolis flammea multiple nucleocapsid nuclear polyhedrosis virus (PfMNPV) was originally isolated from a natural virus epizootic and shown to consist of a mixture of variants. Two subclasses of variants (PfMNPV A and B) were identified by Southern blot hybridization, their polyhedrin genes being located on different restriction fragments. The proportion of the A and B variants changed according to the larval host in which the virus was propagated; PfMNPV(B) predominated in P. flammea but PfMNPV(A) was predominant in Mamestra brassicae. Bioassays of the two pure virus variants in M. brassicae larvae have shown the LD50 values to be 4610 polyhedron inclusion bodies (pibs) for PfMNPV(A) and 5937 pibs for PfMNPV(B). Genomic DNA from the two variants was compared using restriction endonuclease analysis, and dot blot and Southern blot hybridization. Reciprocal quantitative dot blot hybridization analysis in 50% formamide showed PfMNPV(A) and PfMNPV(B) to be only distantly related to Autographa californica MNPV (less than 1%) and more closely related to M. brassicae MNPV (21 to 26%). The two PfMNPV variants exhibited a very high degree of identity to each other (nearly 100%) and therefore are very closely related. This was confirmed by physical mapping of the virus genomes. The nucleotide sequence of the polyhedrin gene of PfMNPV(B) was determined and compared with the published DNA sequences of other polyhedrin genes.

Animals↗
PubMed1991

Secretion of single-chain urokinase-type plasminogen activator from insect cells.

A cDNA encoding human urokinase-type plasminogen activator was inserted downstream from the polyhedrin promoter of the baculovirus Autographa californica nuclear polyhedrosis virus. A protein of similar Mr to urokinase (UK) was synthesized and approx. 90% was secreted from recombinant virus-infected Spodoptera frugiperda cells. Zymography and Western blotting analysis of the insect-derived protein demonstrated that it was comprised solely of the high-Mr form of UK. No low-Mr UK was detected. Amidolytic activity assays showed that 96% of the insect cell-derived UK was in the single-chain proenzyme form. The yield of UK from insect cells was 1986 international units/ml/10(6) infected cells.

Animals↗
PubMed1991

Concomitant whole-abdominal radiation and intraperitoneal chemotherapy in advanced ovarian carcinoma. A pilot study.

Because the use of cisplatin-based chemotherapy for ovarian carcinoma has not significantly improved 5-year survival rates compared with either whole-abdominal radiation (WAR) or single-agent chemotherapy, a pilot study was begun to assess the feasibility of concomitant radiation and chemotherapy. Eleven previously untreated patients with Stages III and IV ovarian carcinoma were treated concomitantly with 2000 cGy of WAR and intraperitoneal (IP) cisplatin followed by additional IP cisplatin after debulking surgery. Toxicity was moderate to severe. Sixty-four percent of patients had Grades 3 to 4 hematologic toxicity, and 36% required hospitalization for sepsis during WAR/IP cisplatin. Hematologic toxicity was less pronounced during IP cisplatin alone. All patients experienced moderate gastrointestinal toxicity. The average percentage of total body weight lost was 13.5%. Fifty-five percent of all patients demonstrated a complete clinical response to therapy, and patients with minimal postoperative residual disease fared better. One patient with persistent disease had acute nonlymphocytic leukemia (ANLL) 24 months after initial diagnosis. No patients with residual disease greater than 20 mm survived, while 50% of patients with less than 20 mm are clinically free of disease. Toxicity appears to be additive with the combination of WAR and IP cisplatin. Therapeutic efficacy was comparable with standard chemotherapy regimens, but no therapeutic or survival advantages were demonstrated with the use of this treatment protocol.

Adult↗
PubMed1991

Adenovirus 21 infection in an isolated antarctic station: transmission of the virus and susceptibility of the population.

Natural dissemination of viral respiratory illness to susceptible men may occur with surprising difficulty. This was especially evident during a 1977 outbreak of adenovirus type 21 (Ad-21) at McMurdo Station, a US research base in Antarctica. The unique circumstances at McMurdo allowed 125 men from the US to join and intermingle with 75 men who had wintered for 6 months in complete isolation. For an additional 5-week (September 2 to October 4, 1977) isolation period, respiratory illness etiology and transmission were monitored in the combined population. A total of 89% of the population was susceptible (neutralizing antibody titer, less than 1:3) to Ad-21 but only 15.0% were infected. Illness spread very slowly (1.5 cases/100 persons/week) with no epidemic peak and was much less severe than Ad-21 outbreaks in other settings. The incidence of infection (17.3%) and illness (9.6%) was low even in men who had wintered over, with values very similar to those of the newcomers (13.9% and 8.9%, respectively). Thus, despite a harsh environment and frequent prolonged gatherings of susceptible personnel, even a respiratory virus type with known epidemic potential was surprisingly difficult to transmit.

Adenovirus Infections, Human↗
PubMed1991

Treatment of advanced epithelial ovarian carcinoma in pregnancy with cisplatin-based chemotherapy.

Malignant ovarian neoplasms associated with pregnancy are uncommon, and the majority of these are Stage I. While adjuvant chemotherapy for germ cell tumors during pregnancy has been reported, only one previous report exists on the use of cisplatin-based chemotherapy for epithelial ovarian carcinomas during pregnancy. A patient with Stage III cystadenocarcinoma of the ovary treated during pregnancy with five courses of dose-intensive cisplatin and cyclophosphamide is presented. No adverse fetal effects secondary to cisplatin-based chemotherapy were noted. A review of the literature is presented.

Adult↗
PubMed1991

Validity issues in research on Vietnam veteran adjustment.

For 2 decades America's Vietnam veterans have been viewed as presenting special problems, and researchers from various disciplines have attempted to understand the network of cause-and-effect relationships accounting for their psychosocial status. In this article, Cook and Campbell's (1979) framework is used to examine validity issues in Vietnam veteran research. Threats to each of the types of validity (statistical conclusion, internal, construct, and external) are discussed using examples from the literature. To counteract these threats and strengthen future research, 7 recommendations are offered.

Adaptation, Psychological↗
PubMed1991

The integration of whole abdominal radiotherapy and intraperitoneal cisplatin into the primary management of advanced ovarian carcinoma.

Eleven women with Stages III and IV epithelial ovarian carcinomas were entered into a protocol consisting of concurrent whole abdominal radiotherapy and intraperitoneal cisplatin followed by additional intraperitoneal cisplatin. The entire abdomen received 20 Gy in 20 fractions with no renal or hepatic shielding. Intraperitoneal cisplatin dosage was 20 mg/m2 weekly during radiation and 90 mg/m2 monthly thereafter for an additional three courses. Patients with Stages IIIC and IV had a median survival of 18 months and a two-year actuarial survival of 32%. Primary failure sites were the abdomen, pleura, and lymph nodes. Acute toxicity during radiotherapy was comparable to patients treated with radiation alone. No chronic renal, hepatic, or enteric complications were observed. Although the protocol did not have substantial efficacy in advanced disease, its toxicity was moderate enough to consider its use in less advanced cancers with peritoneal metastases. In particular, the protocol can be considered for women with ovarian cancer with no gross residuum and for women with papillary serous carcinoma of the uterine corpus.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1991

Drawing a connection from victim to victimizer.

1. The biological basis of the altered alarm/dissociative process during and after sexual trauma impedes the development of information processing essential for discerning intention, personal responsibility, sense of control over events, and trust in others. 2. Once this imbalance occurs, the child is restricted in developing cognitive schema to deal with interpersonal intimacy. This in turn results in secondary patterns of aggressiveness or avoidance. 3. The implication of this biological understanding of trauma and information processing for treatment underscores the necessity of reducing arousal, thus lessening the dissociative process. Drawings of the criminal act and the victim experience elicit cues connecting the two events, facilitating an increase in personal control over repeated aggressive acts.

Adolescent↗
PubMed1990

Expression and characterization of the chick nicotinic acetylcholine receptor alpha-subunit in insect cells using a baculovirus vector.

A baculovirus transfer vector was constructed containing an entire cDNA copy of the chick nicotinic acetylcholine receptor (nAChR) alpha-subunit under control of the Autographa californica nuclear polyhedrosis virus (AcNPV) polyhedrin gene promoter. Recombinant baculovirus was obtained by co-transfection of Spodoptera frugiperda cells with infectious, wild-type AcNPV DNA and the transfer vector. Polyhedrin-negative, recombinant viruses were identified which expressed the nAChR alpha-subunit. The insect cell-expressed alpha-subunit protein had a molecular mass of 42 kDa and was shown to be targeted to the plasma membrane by fluorescence microscopy and toxin-binding assays. The levels of expression were low, approximately 1-2% of cell proteins, when compared with the levels of natural polyhedrin protein. The expressed receptor alpha-subunit was recognised by polyclonal antisera raised against purified Torpedo nAChR alpha-subunit and carried the binding site for the snake venom toxin, alpha-bungarotoxin. Bound alpha-bungarotoxin was displaced in competition binding assays by alpha-cobra toxin, carbamylcholine and d-tubocurarine, and thus had a similar pharmacological profile to that obtained with authentic receptors in muscle cells and receptors expressed in other systems i.e. Xenopus oocytes and mammalian cells. We have also shown that when the chick nAChR alpha-subunit is expressed in the absence of other receptor subunits, unexpectedly high concentrations of nicotine (10 mM) were required to displace bound alpha-bungarotoxin.

Animals↗
PubMed1990

Symptomatic central venous thrombosis and long-term right atrial catheters.

The use of long-term right atrial access catheters is increasing due to their value as aids in the administration of chemotherapy and hyperalimentation. A rare complication of catheter use is subclavian vein thrombosis. Suspicion of subclavian venous thrombosis based on clinical findings should be confirmed by venography. Therapy should be individualized, but may include antibiotics, catheter removal, thrombolytics, and anticoagulants. Resolution of symptoms is the usual outcome, but this may be influenced by other compounding factors.

Catheterization↗
PubMed1990

Conflict over emotional expression: psychological and physical correlates.

This study addresses the construct of conflict or ambivalence over emotional expression. Ambivalence is seen as an important mediator in the link between emotional styles and psychological and physical well-being. Using the "personal striving" framework, a questionnaire measure of ambivalent emotional strivings (AEQ) was designed. In Study 1, 292 Ss completed this measure along with questionnaire measures of expressiveness, social desirability, and intense ambivalence. Women scored significantly higher than men on both the AEQ and expressiveness. In Study 2, scores on the AEQ were found to be negatively correlated with self-reported and peer-rated expressiveness. In Study 3, 48 Ss participated in a 21-day study of mood and health. Expressiveness was positively correlated with some measures of well-being and with daily negative affect. Ambivalence was positively correlated with several indices of psychological distress. Although the AEQ correlated with questionnaire measures of physical symptomatology, neither the AEQ nor the expressiveness measures correlated with daily symptom reports. Results support the contention that conflict over emotional expressiveness is a variable worthy of study in its own right, having implications for research on personality and health.

Adaptation, Psychological↗
PubMed1989

Prognostic significance of the presence of human papillomavirus DNA in patients with invasive carcinoma of the cervix.

Cases of invasive carcinoma of the uterine cervix were analyzed to determine whether the presence or absence of human papillomavirus (HPV) DNA in the neoplasms was a contributing factor to their outcome. The presence of HPV DNA was evaluated using in situ hybridization on formalin-fixed, paraffin-embedded tissue sections. Eighty-five patients with cervical carcinoma who had been surgically evaluated were included in the study. Data from these patients was analyzed retrospectively to determine survival, recurrence, presence of nodal metastases, tumor grade, mode of therapy, peritoneal fluid cytologic results, and age in relation to presence or absence of HPV DNA. No significant statistical differences were found between the HPV-16-positive, HPV-18-positive, and HPV DNA-negative patients.

Adenocarcinoma↗
PubMed1989

Adenoid cystic carcinoma of the cervix in women under age 40.

Adenoid cystic carcinoma of the cervix, traditionally associated with a poor prognosis, occurs in postmenopausal patients in the vast majority of cases reported. Only four cases have been reported in women less than age 40, and none in women less than age 30. Three new cases of adenoid cystic carcinoma of the cervix are reported in women aged 24, 27, and 38 years. All three patients were treated with radical pelvic surgery; lymph node metastases and vascular involvement were prominent. Adjuvant chemotherapy with cisplatin was used in two patients, one of whom has had long-term survival. A review of the literature is also presented.

Adenocarcinoma↗
PubMed1989

Personal striving differentiation and affective reactivity.

Examined the relation between affective reactivity (intensity and variability of mood) and cognitive differentiation through the personal striving (Emmons, 1986) framework in order to test the hypothesis that affective reactivity underlies differentiation. 88 Ss in 2 samples listed 15 of their personal strivings and rated them with respect to 3 measures of striving differentiation (interdependence, dissimilarity, and plans for accomplishing each). Experience-sampling and daily mood ratings were used to assess affect intensity and affect variability over a 3-week period. Emotionally reactive Ss possessed a more differentiated striving system. However, they generated fewer plans for accomplishing each striving than did less reactive Ss. Results are interpreted in terms of Larsen and Diener's (1987) arousal regulation theory of affect intensity and Linville's (1982, 1985) self-complexity/affect-extremity model.

Adult↗
PubMed1989

Resection of the pubic bone as an adjunct to management of primary, recurrent, and metastatic pelvic malignancies.

Patients with locally advanced vulvovaginal carcinomas with pubic bone encroachment or fixation pose a treatment dilemma. The purpose of this study was to evaluate the outcome in 12 patients who have undergone pubic bone resection at the University of Minnesota as part of treatment of locally extensive primary, recurrent, or metastatic vulvovaginal carcinomas. Six patients with primary vulvar carcinomas and six patients with recurrent or metastatic vulvovaginal carcinomas underwent bone resection as part of their surgical therapy. Survival in the primary treatment group was 50%, with no local recurrences. Survival in the recurrent/metastatic disease group was 83%, with a follow-up time of 9 months to 15 years. One vulvar and one groin recurrence have occurred in the recurrent/metastatic group. Pubic bone resection added little to surgical morbidity and gave good functional results. Pubic bone resection, in combination with radical extirpative procedures, is an option for treatment of patients with locally extensive vulvovaginal carcinomas, particularly those with previous radiation therapy.

Adenocarcinoma↗
PubMed1989

Efficient transfection of insect cells with baculovirus DNA using electroporation.

Efficient transfection of Spodoptera frugiperda cells with Autographa californica nuclear polyhedrosis virus (AcNPV) DNA has been carried out using the technique of electroporation. The efficiency of transfection was monitored by assaying the extracellular virus in cell culture supernatants 3 days post-electroporation. Maximum titres of 2 x 10(9) p.f.u./ml AcNPV were obtained when using a pulse length of 7.7 ms and a field strength of 500 V/cm. This compared with a titre of 2 x 10(6) p.f.u./ml AcNPV using the standard calcium phosphate transfection method. Cotransfections of wild-type AcNPV DNA and the transfer plasmid pAcRP23-lacZ were also performed using electroporation and gave beta-galactosidase recombinant virus titres of 5 x 10(4) p.f.u./ml; this compared with 5 x 10(2) p.f.u./ml using the calcium phosphate method. The maximum proportion of recombinant virus, 2.9%, was obtained by harvesting the transfection medium after 2 days, and using a pulse length of 2.8 ms and a field strength of 750 V/cm. We therefore conclude that electroporation provides a very efficient method for the transfection of insect cells with baculovirus DNA.

Animals↗