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Biomedical subjects

D R White

Publications and source records attributed to D R White.

At least 37 records · Page 2Linked to original sources

Adolescents' weight, sex, and family functioning.

The study explored family functioning with adolescents of varying weight. The participants were 572 adolescents (286 boys and 286 girls) (M = 15.7 years, SD = 1.04) who comprised four weight groups: underweight (less than 90% expected weight), normal weight (90 to 110%), overweight (111 to 125%), and obese (over 125%). They completed 9 of the 15 subscales of the Self-Report Measure of Family Functioning pertaining to family styles (e.g., Authoritarian) and relationships (e.g., Conflict, Enmeshment). Obese girls rated their families lower on Cohesion, Expressiveness, and Democratic Family Style. Obese and moderately overweight girls seem to perceive their families differently. Obese and overweight boys did not differ from normal weight boys on any of the measures. There was a tendency for underweight boys to report lower Cohesion, Expressiveness, and Democratic Family Style. The need to consider family environment, particularly the family's differing expectations for obese daughters and underweight sons, is discussed with reference to treatment.

Adolescent↗

Complementary effects of propranolol and nonoxynol-9 upon human sperm motility.

The inhibitory effects of nonoxynol-9, DL- and D-propranolol upon human sperm motility were determined in vitro. All three compounds were capable of causing complete cessation of sperm movement. However, greater efficacy was achieved using combinations of nonoxynol-9 and propranolol, suggesting a complementary interaction between these compounds. Investigations of the mechanism of action of propranolol revealed that an influx of calcium accompanied the loss of motility. However, since incubation in the absence of calcium enhanced the spermicidal effects of this compound, it was concluded that this calcium influx did not constitute the primary means by which motility was disrupted. Low doses of propranolol, which did not affect motility, were found to inhibit the capacity of human spermatozoa for sperm-oocyte fusion.

Calcium↗

Age-related changes in auditory evoked potentials of gerbils. III. Low-frequency responses and repetition rate effects.

The auditory brainstem response (ABR) was recorded non-invasively from Mongolian gerbils ranging in age from 6 to 36 months. The ABR was elicited using gaussian tone bursts at octave intervals from 1 to 16 kHz. Responses were bandpass filtered from 30 to 300 Hz (LF-ABR; low-frequency component) and from 300 to 3000 Hz (HF-ABR; high-frequency component). In Experiment A, the thresholds of the two components (HF- and LF-ABR) were compared in 6- and 36-month subjects. The LF-ABR varied more with age than did the HF-ABR, particularly at stimulus frequencies of 2 kHz and above. As shown previously for the HF-ABR, the latencies of the LF-ABR increased as a function of hearing loss in aged gerbils whereas amplitudes of the LF-ABR were reduced in all aged gerbils, regardless of age-related threshold elevation. In Experiment B, tone bursts were presented at rates of 11-91/s to gerbils aged 6, 18, 30, and 36 months. Increased repetition rate resulted in an increase in the latency of both the HF- and LF-ABR, but to the same degree in each age group. Similarly, the interpeak intervals of the HF-ABR increased as a function of repetition rate in all subjects to the same degree. Increased age and increased repetition rate both resulted in significant reductions in ABR amplitudes, but rate did not interact with age. The data suggest that (1) the LF-ABR may be more sensitive to aging than is the HF-ABR and (2) there are no age-related changes in the HF- or LF-ABR which are dependent upon the repetition rate.

Acoustic Stimulation↗

Children's global self-esteem predicted by body-esteem but not by weight.

Three factors of a body-esteem scale, Appearance, Weight, and Attribution, were inversely related to relative weight in youngster between 8 and 16 years old (243 girls and 168 boys). Global self-esteem, however, was generally not related to relative weight. Nonetheless, self-esteem covaried with Appearance and Attribution.

Adolescent↗

Detection of fetal twins in sheep using a radioimmunoassay for pregnancy-specific protein B.

Ovine pregnancy-specific protein B (oPSPB) was isolated from sheep placentas. Antiserum to oPSPB was developed in rabbits. A quantitative RIA was developed and used to assay the serum concentrations of oPSPB during and after pregnancy in ewes bearing single or twin fetuses. Suffolk and Panama ewes, kept with rams equipped with a marking harness, were checked daily for breeding marks as an indication of estrus and bled daily between 10 and 30 d after marking. Ovine PSPB became detectable at 19.7 +/- .14 (mean +/- SE) d after breeding and increased steadily to d 30. Panama oPSPB concentration increased at a greater rate than that of Suffolks (breed x day interaction, P < .01). Ten ewes were bled twice weekly 3 wk before their expected date of lambing and weekly for 7 wk postpartum. Serum concentrations differed considerably between prepartum ewes, but concentrations remained stable within the period of 20 d prepartum. Following parturition, oPSPB concentrations dropped rapidly. In nine ewes, oPSPB was last detectable at 12.78 +/- 2.26 (mean +/- SE) d postpartum. In the 10th ewe, oPSPB was .65 ng/mL at the last sample on d 46 postpartum. To determine the effect of fetal number on oPSPB concentrations, ewes in which estrus was synchronized were bled at d 18, 25, 38, 60, 90, and 120 after breeding. Ewes were killed at d 60, 90, 120, and 148 and fetal number determined. There was a significant (P < .01) difference in the log of oPSPB concentrations according to number of fetuses, day postbreeding, and the day x fetal number interaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

An outbreak of group C streptococcal infection in a maternity unit.

An outbreak of Group C streptococcal infection (Streptococcus equisimilis serotype T204) occurred in a Maternity Unit in Durham over a 2-week period. The outbreak strain possessed an M-protein antigen identical to that found in a previously reported Maternity Unit outbreak. Seven patients in total were affected, and in two patients infected perineal wounds took several weeks to heal. The source of the outbreak appeared to be a patient who developed a perineal wound infection and who subsequently returned to the ward for reassessment. Environmental contamination is likely to have been the reservoir of infection for the subsequent patients. The outbreak was controlled by applying strict infection control procedures and establishing a high standard of routine cleaning.

Cross Infection↗

A phase I-II study of recombinant intrapleural alpha interferon in malignant pleural effusions.

Malignant pleural effusion is a common and significant source of morbidity for many patients with cancer. In an attempt to control this condition without using chest tube drainage, we administered recombinant interferon alpha-2b (INTRON, Schering-Plough, Kenilworth, NJ) intrapleurally via catheter after routine thoracentesis. Twenty-two installations of interferon were administered to 15 patients in incremental dosages of 3-50 x 10(6) U/m2. Of 20 evaluable treatments, six (30%) achieved effusion stabilization; there were no complete or partial responses. Only one of nine treatments at a dosage less than 20 x 10(6) units/m2 resulted in symptoms, while four of 11 treatments at the higher dosage were associated with transient fever, chills, and chest pain. Interferon demonstrated no major activity in this heavily treated patient population with advanced malignancy.

Adult↗

Interrupted versus continuous chemotherapy in patients with metastatic breast cancer. The Piedmont Oncology Association.

BACKGROUND: Chemotherapy for metastatic breast cancer is palliative, and the optimal duration of therapy is unknown. We designed a trial to determine whether continuous treatment is superior to stopping treatment after a brief induction period and resuming treatment when the disease progresses. METHODS: We treated 250 women with metastatic breast cancer with six courses of cyclophosphamide, doxorubicin, and fluorouracil given every three weeks. At the completion of this induction period, women whose disease either regressed or remained stable were randomly assigned to receive either continued treatment with cyclophosphamide, methotrexate, and fluorouracil (maintenance therapy) or no further treatment (observation) followed by treatment with cyclophosphamide, methotrexate, and fluorouracil when disease progression became evident (reinduction). RESULTS: The combined rate of complete and partial responses after initial therapy was 30 percent (71 of 233 patients who could be evaluated; 95 percent confidence interval, 25 percent to 37 percent). In another 42 percent (98 patients), the disease remained stable. A total of 145 patients were randomized. Seventy-one were randomly assigned to the maintenance-therapy group, and 74 to the observation group. The median time to progression was 9.4 months for patients in the maintenance-therapy group and 3.2 months for patients in the observation group (P less than 0.001). After reinduction therapy, the median time to progression was 3.5 months. The median length of survival from the time of initial therapy was 14.8 months for all 250 patients; it was 21.1 months for the 71 patients in the maintenance-therapy group and 19.6 months for the 74 patients in the observation group (P = 0.67). Maintenance therapy was the most important determinant of the time before progression (P less than 0.001), but it was not associated with prolonged survival. The changes in performance status were similar in the patients in both groups, but nausea, vomiting, and mucositis were significantly more frequent in the maintenance-therapy group. CONCLUSIONS: In patients with breast cancer who received induction chemotherapy for 18 weeks, subsequent continuous chemotherapy was associated with a significant prolongation of the time before progression as compared with those receiving no further therapy; overall survival, however, was not significantly different in the two groups.

Adult↗

A randomized trial of chemotherapy (L-PAM vs CMF) and irradiation for node positive breast cancer. Eleven year follow-up of a Piedmont Oncology Association trial.

158 evaluable patients with stage II, lymph node positive, carcinoma of the breast were randomized to adjuvant therapy with either melphalan (L-PAM) or cyclophosphamide, methotrexate, and fluorouracil (CMF) after mastectomy. In addition, patients were randomized to be treated with or without post-operative irradiation therapy (RT) in addition to their chemotherapy. At a median follow-up time of 11 years, there is no difference in time to relapse (P = 0.69) or survival (P = 0.55) among the four treatment groups. Multivariate analysis including treatment arm, age, race, tumor size, histologic type, performance status, time to onset of treatment, menopausal status, and number of positive nodes, revealed that only the number of positive nodes (less than 4 vs greater than or equal to 4) was related to disease-free and overall survival. Ten year relapse-free survival for patients with less than 4 positive nodes compared to those with greater than or equal to 4 positive nodes was 63% versus 30%, and overall survival 63% versus 41%, respectively. Patients who received post-operative radiation therapy had significantly less local recurrence than those treated with chemotherapy alone (P = 0.03) but without improvement in relapse-free or overall survival. In this trial, post-operative radiation therapy when added to chemotherapy decreased the risk of local recurrence without adverse effects on survival. Treatment outcome was not influenced by chemotherapy regimen, but differences may have been obscured by the small sample size.

Adult↗

The composition of body tissues (II). Fetus to young adult.

The composition of body tissues is a function of the age, nutrition, state of health and physical activity of the individual. In this paper, the effects of age on the composition of healthy tissues are reviewed. Eleven soft tissues (adipose tissue, blood--whole, brain--whole, heart, kidney, liver, lung, muscle--skeletal, placenta, skin and spleen) and cortical bone are considered. Elemental compositions, mass and electron densities are tabulated for the tissues, as a function of age, from fetus to young adult. Although the compositions given here are predominantly for healthy tissues, reported changes because of dietary influences are briefly discussed.

Adolescent↗

Gender differences in categorizing adolescents' weight status.

Categorization of normal or overweight status, using percent overweight and visual inspection, showed good agreement for 51 adolescent girls, but not 70 boys. Only 49% of boys with high relative weights were seen as overweight compared to 90% of girls.

Adolescent↗

A phase II trial of high-dose cytarabine and cisplatin in previously untreated non-small cell carcinoma of the lung. A Piedmont Oncology Association Study.

Thirty-seven chemotherapy-naive patients with advanced non-small cell lung cancer (NSCLC) were treated with cytarabine (3 g/m2 intravenously [IV] during 3 hours) after IV bolus cisplatin (100 mg/m2 repeated every 3 weeks). Aside from nausea and vomiting, the principal toxicity was hematologic, with Grade IV myelosuppression in 32% and Grade III in 14%. Four patients died while on study. One complete and four partial responses were observed for an overall response rate of 14%. Responses were limited to lymph node and lung metastases and occurred in two of 17 adenocarcinomas, two of 12 squamous cell carcinomas, and one of eight large cell carcinomas. At this dose, the plasma level of cisplatin is only 3 micrograms/ml and the plasma level of cytarabine is 10 to 50 micrograms/ml, compared with the levels of 10 micrograms/ml and 1000 micrograms/ml, respectively, required for in vitro synergy. The severity of myelotoxicity observed indicates that, even at these levels, cisplatin enhances cytarabine activity. The combination may prove useful in malignancies that are sensitive to cytarabine, but is not of benefit in cytarabine-resistant malignancies such as NSCLC.

Adult↗

Combination high-dose etoposide and vincristine infusion.

Following the identification of a synergistic antitumor effect in a murine model, the combination of etoposide and vincristine has been explored in the clinic. Etoposide was given at 4 dose levels (250, 500, 750 or 1,000 mg/m2) with each dose given in 3 equal fractions daily for 3 days. The dose of vincristine was fixed (two 0.75 mg infusions over 22 hours each between doses of etoposide). A total of 26 patients were entered into study and 7, 11, 10 and 5 patients were treated at the 250, 500, 750, and 1,000 mg/m2 dose levels, respectively. Myelosuppression was the principle side effect and Grade 4 WBC toxicity (less than 1,000/mm3) developed in 14%, 27%, 40% and 40%, respectively, of the patients treated at each of these respective dose levels. Life-threatening infections occurred in 0%, 9%, 30% and 60% of the patients at these levels, respectively. Reversal of marrow toxicity was rapid with repeat courses given at 3-week intervals. Non-hematologic toxicity, including neurotoxicity, nausea, vomiting, and mucositis was generally mild when present. Objective responses were observed in 1 patient each with refractory Hodgkin's disease and immunoblastic lymphoma. Prolonged periods of stable disease occurred in 2 patients with adenocarcinoma of the lung and one patient with Hodgkin's disease. The starting dose of etoposide recommended for further trials of this agent in combination with infusion of vincristine is 500 mg/m2 given in fractionated doses; dose escalation should be possible in many patients.

Antineoplastic Combined Chemotherapy Protocols↗

A phase II trial of PEG-L-asparaginase in the treatment of non-Hodgkins lymphoma.

A polyethylene glycol conjugate of L-asparaginase (PEGLA) was administered to 21 patients with refractory non-Hodgkin's lymphoma. The dose given was 2,000 mu/m2 intramuscularly every 2 weeks. Eligibility required at least one prior trial of chemotherapy and ambulatory performance status. At entry, all patients had measurable lesions and documented disease progression. The median age of the patients was 61 years; 18 (86%) were ambulatory with minimal symptoms, 12 patients (57%) had 3 or more prior regimens, and 13 (62%) had stage IV disease. Histologic subtype was low grade in 11 patients (52%), intermediate in 7 (33%), high grade in 2 (10%) and unclassifiable in one (5%). There were two partial responses (11%) noted (95% confidence interval of response of 1-30%). Eleven patients (52%) were removed from study due to disease progression. Nine patients (43%), required removal for toxicity (7 for protracted nausea and vomiting and 2 for confusion). One patient died of sepsis while on study but this was not considered drug related. Almost one third of patients complained of fatigue or loss of appetite. Nausea and vomiting occurred in approximately half the patients and was moderate to severe in 9. Diarrhea and abdominal pain were also noted in one-third of those treated. Changes in the partial thromboplastin time and fibrinogen were noted in most patients but resulted in no bleeding complications. In this trial, PEGLA displayed modest activity in a heterogenous group of patients with progressive non-Hodgkin's lymphoma.

Adult↗

Factors affecting the acrosome reaction in human spermatozoa.

Large pieces of human cumulus oophorus were exposed for 20-30 min to washed spermatozoa or to spermatozoa recovered after a swim-up procedure, and then fixed for electron microscopy. Spermatozoa of both populations penetrated deeply into the cumulus within that time, and none of 48 observed clearly had undergone an acrosome reaction (AR). As measured by fluorescence microscopy, an AR rate of 12% in spermatozoa obtained at 4 h following a swim-up increased to about 25% in samples incubated in culture dishes for approximately 20 h. However, this latter AR rate was no different in the presence or absence of a cumulus/oocyte complex, and was only moderately greater in 50% follicular fluid. Nor was it affected to any degree by the absence of calcium or by a low (26 degrees C) temperature, both of which are regulators of the physiological AR in other species. By contrast, a clear dose-related enhancement of the AR by the calcium ionophore A23187 was almost completely Ca2(+)-dependent. We conclude that the human cumulus oophorus does not rapidly induce an AR in spermatozoa capacitated in vitro and, unlike the situation in some other mammals, that washed human spermatozoa do not first require a period of capacitation in order to penetrate it. The results also point to the likelihood that ARs monitored in free-swimming human spermatozoa are for the most part spurious or artefactual, and they show that in-vitro AR rates in such populations do not parallel their fertilizing ability.

Acrosome↗

Vincristine infusion with CHOP-CCNU in diffuse large-cell lymphoma.

Phase I and II trials of vincristine infusion have demonstrated the safety and efficacy of this approach in the treatment of patients with refractory non-Hodgkin's lymphoma. Subsequently, a trial was designed to evaluate this technique in untreated patients. Repeated 5-day infusions of vincristine 0.25 mg/m2 per day were incorporated into a CHOP-CCNU regimen and administered to 24 patients with advanced diffuse large-cell lymphoma. Objective responses occurred rapidly and were observed in 18 (75%) patients in whom 13 (54%) were complete. Toxicity was generally mild to moderate and neurotoxicity appeared to be no worse than typically observed with bolus vincristine. Complete responses have been durable in most patients and 10 (77%) of the complete responders have not relapsed. At this time, 9 (38%) of the total patients remain alive and without evidence of disease from 3.8 to 7.3 years from the start of treatment. One patient died of disseminated gastric cancer at 3.3 years from the start of therapy and there was no evidence of lymphoma at exploratory laparotomy. Infusion of vincristine may be safely incorporated into multiagent chemotherapy programs of the CHOP type for non-Hodgkin's lymphoma. Its potential for protracted nonmyelosuppressive cell kill would appear attractive in designing future trials for this disease.

Adult↗

Mitoxantrone and high-dose ara-C in refractory malignancies: a phase I trial.

On the basis of in vitro studies demonstrating marked synergy between mitoxantrone and high-dose cytosine arabinoside (ara-C) (HiDAC) against L5178Y murine leukemia and clinical studies showing usefulness of the combination in patients with refractory acute myeloid leukemia, a phase I study was initiated to find tolerable doses for use in patients with refractory solid tumors. Initial dose levels were mitoxantrone 2 mg/m2 infused over 30 minutes, followed by high-dose ara-C 750 mg/m2 infused over 3 hours repeated once at 24 hours (total dose 4 mg/m2 mitoxantrone and 1,500 mg/m2 HiDAC per 2-day course), with planned subsequent escalation of mitoxantrone. Moderate-to-severe myelosuppression, however, required sequential dose reduction of both agents. Nonhematologic toxicity was restricted to manageable nausea and vomiting in one-half the patients and a single episode of transient delirium of uncertain etiology. No responses were observed in 23 heavily pretreated patients with a wide variety of malignancies. On the basis of this study, doses of 187-375 mg/m2 ara-C given every 24 hours for two doses following mitoxantrone 1 mg/m2 every 24 hours for two doses would be tolerated by most patients with subsequent dose escalation in some as allowed by myelosuppression.

Adult↗