Search PubMed⌕ Search

Biomedical subjects

B Cantwell

Publications and source records attributed to B Cantwell.

At least 19 recordsLinked to original sources
PubMed2001

Prevalence of persistent asymptomatic proteinuria in HIV-infected outpatients and lack of correlation with viral load.

AIM: Human immunodeficiency virus-associated nephropathy (HIVAN) is projected to be a leading cause of end-stage renal disease (ESRD) in young African American men in the new millennium. Little is known about the early natural history of the disease, including the prevalence of asymptomatic nephropathy. The primary aim of this study was to define the prevalence of persistent asymptomatic proteinuria in a contemporary, ambulatory human immunodeficiency virus- (HIV) infected population. The secondary aim was to correlate the presence of persistent proteinuria with measures of HIV disease. METHODS: Using a readily available screening tool, the urine dipstick, we determined the prevalence of persistent asymptomatic proteinuria in the outpatient VA Connecticut (VA CT) Healthcare System West Haven HIV Clinic population. We compared the presence of persistent proteinuria with measures of HIV viral disease. RESULTS: The prevalence of persistent asymptomatic proteinuria was 14% (7 of 49 patients). The presence of persistent proteinuria was not correlated with viral load. CONCLUSIONS: A significant prevalence of occult renal disease exists in the asymptomatic HIV-seropositive outpatient population and is not correlated with viral load.

AIDS-Associated Nephropathy↗
PubMed1998

Self detoxication by amphetamine dependent patients: a pilot study.

Fifty current or past amphetamine dependent clients attending a Community Drug and Alcohol Team service took part in structured interviews about their previous attempts to stop using amphetamine. Thirty three had made a total of 47 attempts at self detoxication; 15 had undergone enforced withdrawal and ten had previously sought medical treatment. A total of 86% of subjects described significant withdrawal symptoms on stopping use of amphetamines. Increased use of other drugs was commonly reported as a means of coping with withdrawal, psycho-social techniques being used less systematically. The implications for the provision of attractive, effective treatments are discussed.

Adolescent↗
PubMed1995

The Myxococcus xanthus asgA gene encodes a novel signal transduction protein required for multicellular development.

The Myxococcus xanthus asgA gene is one of three known genes necessary for the production of extracellular A-signal, a cell density signal required early in fruiting body development. We determined the DNA sequence of asgA. The deduced 385-amino-acid sequence of AsgA was found to contain two domains: one homologous to the receiver domain of response regulators and the other homologous to the transmitter domain of histidine protein kinases. A kanamycin resistance (Kmr) gene was inserted at various positions within or near the asgA gene to determine the null phenotype. Those strains with the Kmr gene inserted upstream or downstream of asgA are able to form fruiting bodies, while strains containing the Kmr gene inserted within asgA fail to develop. The nature and location of the asgA476 mutation were determined. This mutation causes a leucine-to-proline substitution within a conserved stretch of hydrophobic residues in the N-terminal receiver domain. Cells containing the insertion within asgA and cells containing the asgA476 substitution have similar phenotypes with respect to development, colony color, and expression of an asg-dependent gene. An analysis of expression of a translational asgA-lacZ fusion confirms that asgA is expressed during growth and early development. Finally, we propose that AsgA functions within a signal transduction pathway that is required to sense starvation and to respond with the production of extracellular A-signal.

Amino Acid Sequence↗
PubMed1994

Results of chemotherapy using ifosfamide with doxorubicin in advanced breast cancer.

Ifosfamide has single agent activity in advanced breast cancer and may potentiate the activity of doxorubicin. The combination of ifosfamide 5 g/m2 and doxorubicin 40 mg/m2 every 3 weeks for 4 cycles was used to treat 77 patients with advanced breast cancer. Fifty three patients had not received prior chemotherapy. All patients had one or more poor prognostic features, including tumor expression of epidermal growth factor receptor in 11/12 tested. The overall response rate was 74% (95% confidence intervals 62%-83%). The median survival was 9.4 months. The principal toxicities were febrile neutropenia and ifosfamide encephalopathy each in 6% of patients. A high percentage of the projected dose intensity was administered. This is a highly active combination with acceptable toxicity in advanced breast cancer, although the long term survival remains poor. Further exploration of ifosfamide in combination chemotherapy for advanced breast cancer is warranted.

Adult↗
PubMed1994

Evidence that asgB encodes a DNA-binding protein essential for growth and development of Myxococcus xanthus.

The asg mutants of Myxococcus xanthus are defective in production of extracellular A-signal, which serves as a cell density signal for fruiting-body development. The DNA sequence of asgB, one of the three asg genes, was determined. The deduced amino acid sequence of AsgB contains a DNA-binding helix-turn-helix motif near the C terminus. This putative helix-turn-helix is highly similar to the helix-turn-helix in region 4.2 of major sigma factors, which is the region that recognizes and interacts with -35 sequences of promoters. We propose that AsgB is a transcription factor that binds to DNA sequences similar to the -35 hexamer, TTGACA. Analyses of asgB RNA levels and expression of an asgB-lacZ translational fusion indicate that expression of asgB remains fairly constant during the transition from growth into early development. The mutation within the asgB480 allele was identified as an A-to-G transition that results in a threonine-to-alanine substitution in the predicted protein product. Attempts to replace the wild-type copy of asgB with a null allele failed, indicating that asgB may be essential for growth.

Amino Acid Sequence↗
PubMed1991

BOP/VIP--a new platinum-intensive chemotherapy regimen for poor prognosis germ cell tumours.

Ninety-one patients with poor prognosis non-seminomatous germ cell tumours (NSGCT) were treated with an initial intensive chemotherapy schedule. Suitable patients fulfilled one or more of the following criteria: lymph node metastases greater than 10 cm diameter; liver, brain or bone metastases; serum HCG level greater than 50,000 IU/L; and extragonadal primary tumours. Treatment consisted of 3 cycles of bleomycin, vincristine and cisplatin (BOP) administered at 10 day intervals, followed by 3 cycles of etoposide, ifosfamide and cisplatin (VIP) at 21 day intervals. A total of 64 patients (70%) achieved a complete remission. This comprised 46 patients who received BOP/VIP only, and 18 patients who received additional chemotherapy after BOP/VIP. Of these 64 patients, 51 underwent complete surgical resection of residual masses, including 11 in whom there was evidence of teratoma with cellular atypia or non-germ cell cancer in the resected tissue. A further 9 patients had persisting unresected radiological masses in the presence of marker complete remission. The overall response rate was 80%. Currently 57 patients (63%) remain alive and free from disease progression. The median follow-up period is 90 weeks (range 24-206 weeks), with a 2 yr actuarial progression-free survival of 66% (95% c.i. 55-77%). Major toxicity was myelosuppression, occurring during the VIP arm of therapy, with a median nadir WBC of 1.1 x 10(9)/L and median platelet count of 51 x 10(9)/L. Other toxicity included peripheral neuropathy (WHO Grade 2 and 3 in 22%). We conclude that treatment results with the BOP/VIP schedule in this poor prognosis patient group are at least comparable with other schedules, and toxicity is manageable.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

Suppression of postmenopausal ovarian steroidogenesis with the luteinizing hormone-releasing hormone agonist goserelin.

Twenty-one postmenopausal women with advanced breast cancer were treated with monthly 3.6-mg sc injections of the LHRH agonist goserelin [D-Ser-(But)6, Azgly10-LHRH] to determine whether the resultant endocrine changes could provide an explanation for the clinical responses that occur during therapy with this agent. After 4 weeks, serum gonadotropin levels were less than 10% of pretreatment levels, whereas serum PRL levels did not change. A significant decrease in serum testosterone occurred in 19 of 20 patients; this fall was associated with a 22% fall in serum estradiol levels. Serum androstenedione levels also decreased, but serum estrone and dehydroepiandrosterone sulfate (DHAS) levels did not. The lack of fall in serum DHAS levels indicates that the changes in androgen levels were a result of reduced ovarian secretion, and the reduced estradiol levels were a consequence of reduced precursor (i.e. testosterone) availability. The continued dependence of ovarian androgen secretion on gonadotropin stimulation after the menopause may explain the responses of some patients to LHRH agonists and some other therapeutic agents of unknown or uncertain modes of action.

Aged↗
PubMed1988

A modified, event-related potential-based guilty knowledge test.

Subjects chose and pretended to steal one object from a box of nine. They then watched a visual display of verbal representations of objects including their chosen object or one of eight novel objects on each trial. They were told to count one of the novel objects and that although they were welcome to try to beat our test, they would be unable to avoid noticing the chosen object. P3 responses were obtained only to counted and to chosen objects in 7 of 10 subjects not eliminated for artifact or noncooperation.

Guilt↗
PubMed1987

Late vertex positivity in event-related potentials as a guilty knowledge indicator: a new method of life detection.

Subjects were allowed to choose an item to keep from nine items in a box. They then were shown one of nine words randomly selected on a display screen. One of these words described the chosen item, the others described novel items. The subjects were told to try not to react emotionally to any of the words, but to try to defeat this test of deception. It was found that large positive waves with latencies between 400 and 700 ms poststimulus were present in the ERPS to the chosen but not to the novel words.

Adolescent↗