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R Birch

Publications and source records attributed to R Birch.

At least 19 recordsLinked to original sources
PubMed1992

Quality control of dietary data collection in the CARDIA study.

The Coronary Artery Risk Development in (Young) Adults (CARDIA) Study developed and implemented quality control (QC) measures to minimize misclassification associated with dietary data. Manual and automated data inspection were used to monitor quality. Of the 5111 participants who completed a dietary history, 717 (14%) had dietary forms reviewed and 153 (3%) had the interview audiotaped. Results show that for the 717 forms reviewed, the overall form completion error rate was 0.22% and the "critical" error rate (i.e., those errors impacting on nutrient computations) was 0.12%. The proportion of forms free of any type of error increased over time (p less than 0.0001). The discrepancy rate in recording and interviewing methods as estimated from the 153 audiotaped interviews was 0.7%. Inter-interviewer differences were small as indicated by the audiotaped interviews and the proportion of error-free forms completed by interviewers. The results indicate that the dietary data collected in CARDIA were completely and accurately recorded for use in analysis.

Adolescent↗
PubMed1992

Distributed data analysis in a multicenter study: the CARDIA Study.

Unlike distributed data entry, which is used in many large epidemiologic studies and multicenter clinical trials, distributed data analysis is a relatively new concept. This paper reports on the usefulness of such a system in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. CARDIA distributes the entire examination dataset to participating centers soon after completion of each round of data collection. The process was designed to encourage more numerous, diverse, and rapid publications, and to allow for more efficient use of the manpower and expertise in centers. Responsibilities of the coordinating center have changed from a conventional coordinating center but remain substantial due to the need for collating, monitoring, verifying, and documenting the distributed data analysis (DDA) system. DDA is successful from the standpoint of implementation and operation--21 manuscripts representing work analyzed at six participating centers had been submitted for publication within 3.5 years of the completion of the baseline examination.

Adolescent↗
PubMed1992

The long term result of digital nerve repair in no-man's land.

30 isolated lesions of digital nerves which had been repaired by microsurgical techniques were examined in 27 patients. The average length of follow-up was 25 months (range: 12-48 months). Patients were assessed subjectively using a visual analogue scale and examined for light touch, pain, two-point discrimination, electrical conductance and sensory threshold. Although 37% of fingers regained normal two-point discrimination, only 27% of patients graded their overall result as excellent and 40% complained of persistent hyperaesthesia for up to two years. None felt that their finger had regained normal sensation. All patients undergoing digital nerve repair should be warned that hyperaesthesia may persist for several years and that an adult will never regain normal sensation.

Adolescent↗
PubMed1992

Peripheral blood stem cell mobilization by chemotherapy with and without recombinant human granulocyte colony-stimulating factor.

Chemotherapy can serve as a stimulus for mobilizing hematopoietic progenitor cells to the peripheral blood for harvest via leukapheresis. Mobilized peripheral blood stem cells (PBSC) support rapid hematologic reconstitution after bone marrow aplasia induced by intensive myelosuppressive treatments. Our purpose was to develop effective mobilization regimens allowing collection of large quantities of PBSC. We administered high-dose cyclophosphamide (HDC, 4 gm/m2) or cyclophosphamide (4 gm/m2) plus etoposide (600 mg/m2) (HDCE) in a nonrandomized, sequential fashion to 94 patients with breast cancer, lymphoma, and other malignancies with collection of PBSC via leukapheresis during white blood cell (WBC) recovery from nadir counts. Each apheresis product was analyzed for total nucleated cell number, granulocyte-macrophage colony-forming units (CFU-GM) and CD34+ cells. Twenty-four additional patients with comparable pretreatment characteristics received HDCE plus recombinant human granulocyte colony-stimulating factor (HDCE+G) after chemotherapy through the end of apheresis. Patients receiving HDC were matched for age, sex, and disease but were more heavily pretreated. HDCE was superior to HDC in mean daily CFU-GM and CD34+ yield (p < 0.05), even when groups were adjusted for performance status and amount of prior therapy. HDCE+G led to 3.7 times more CFU-GM and 4.7 times more CD34+ cells than HDCE. Target PBSC yield, defined as > 20 x 10(4) CFU-GM/kg and >4 x 10(8) cells/kg, was achieved by 92% of HDCE+G patients after a median of three aphereses, 56% of HDCE patients after five aphereses, and 16% of HDC patients after six apheresis (p < 0.0001). Prior chemotherapy inversely correlated with the quantity of PBSC harvested regardless of regimen utilized. Our results demonstrate effective chemotherapy regimens for harvesting hematopoietic progenitors in a diverse patient population. HDCE+G produced the highest number of progenitors, suggesting that increasing dose intensity and adding rhG-CSF enhances mobilization. Correlation between cumulative CD34+ and CFU-GM allows real-time flow cytometric analysis of the number of aphereses required to harvest target numbers of PBSC.

Adolescent↗
PubMed1992

Lipid and insulin concentrations in obese postmenopausal women: separate effects of energy restriction and weight loss.

The separate effects of energy restriction and weight loss on serum lipids were studied in 24 postmenopausal moderately obese women before and after weight loss of greater than 10 kg to normal weight. Fasting serum triglycerides (TGs), total cholesterol (TC), high-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) cholesterol, and insulin were measured at the end of four 10-d in-hospital phases, two before and two after weight loss: phase I, stable weight; phase II, 3350 kJ/d(800 kcal/d), followed by outpatient weight loss; phase III, 3350 kJ/d (800 kcal/d); and phase IV, stable weight. Diet composition and exercise were constant the entire study. Energy-restriction effect was determined by comparing average values in stable-weight phases (I and IV) with low-energy phases (II and III); weight-loss effect was determined by comparing values in obese phases (I and II) with reduced-weight phases (III and IV). Energy restriction lowered TG, TC, LDL cholesterol, the LDL-HDL cholesterol ratio, and insulin and raised HDL cholesterol (all P less than 0.05). Weight loss lowered TG, TC, LDL cholesterol, and insulin (all P less than 0.01) but did not change HDL cholesterol or the LDL-HDL cholesterol ratio. The results suggest that reduction to a weight-steady nonobese state significantly lowers TG, TC, and LDL cholesterol but does not improve HDL cholesterol or the LDL-HDL cholesterol ratio.

Aged↗
PubMed1992

Nutrient levels in amniotic fluid from women with normal and neural tube defect pregnancies.

We analyzed nutrient levels in amniotic fluid obtained during the second trimester of normal, uncomplicated pregnancies from 221 women who delivered apparently healthy infants and from 8 with neural tube defect (NTD) pregnancies. Folate was measured by microbiological assay, vitamin B12 by a radiobinding method, and zinc, copper and iron by atomic absorption spectrophotometry. We found that the mean amniotic fluid nutrient levels of normal pregnancies were 24.7 nmol/l for folate, 600 pmol/l for vitamin B12, and 1.7, 1.9, and 9.0 mumol/l for zinc, copper and iron, respectively. Amniotic fluid folate, zinc, copper and iron levels of NTD pregnancies were similar to those found during normal pregnancy, however, vitamin B12 levels were markedly lower than those of normal pregnancies.

Adolescent↗
PubMed1992

Cement burn of the sciatic nerve.

We present the case of a 63-year-old woman who sustained an acrylic cement burn of the sciatic nerve at hip replacement. She was treated by resection of the damaged segment and grafting. Electron microscopy showed that the nerve was nearly normal 1 cm from the cement margin indicating that this is a safe level for resection.

Amputation, Surgical↗
PubMed1992

Combination biotherapy utilizing interleukin-2 and alpha interferon in patients with advanced cancer: a National Biotherapy Study Group Trial.

The National Biotherapy Study Group (NBSG) conducted a broad phase II trial using interleukin-2 (IL-2) by continuous infusion and alpha interferon (IFN) subcutaneously in 267 patients with a variety of advanced cancers, including 29 with breast cancer, 89 with renal cancer, and 69 with melanoma. IL-2 [18 million international units (MIU)/m2] was given by continuous infusion for 108 hours with 3 mu/m2 subcutaneous IFN every other day during the IL-2 infusion. The patients were treated for 1 week followed by a 2-week rest. After two cycles of treatment, patients were evaluated for response. Of the 237 patients evaluable for response, 20 (8%) had a complete or partial response and 128 (54%) were stable. Therefore, 62% of the evaluable patients were nonprogressive during the first 90 days of IL-2/IFN therapy. The objective response rate was 11% in melanoma, 7% in renal cancer, 14% in breast cancer, and 3% in patients with a variety of malignancies for an overall response rate of 7% in these patients with advanced cancer. The patients were treated on a general medical ward and tolerated treatment well with fatigue and fever being nearly universal. Dyspnea, pruritus, chills, and elevated creatinines were frequent but less common. This combination biotherapy regimen has minimal activity in a variety of advanced cancers and must be compared with the best existing chemotherapy for each cancer type in randomized, prospective trials.

Adult↗
PubMed1991

Continuous interleukin-2 and tumor-infiltrating lymphocytes as treatment of advanced melanoma. A national biotherapy study group trial.

Melanoma metastases were harvested from 82 patients for the purpose of growing and expanding tumor-infiltrating lymphocytes (TIL). Tumor tissue cell suspensions were incubated with interleukin-2 (IL-2), followed by repeated exposure to tumor antigen with or without OKT3 monoclonal antibody (MoAb). Initial growth success was achieved in 56 of 82 cultures (72%). Efforts were made to expand 26 of these 56 cultures for therapeutic TIL; 23 of 26 early cultures (88%) were successfully expanded for in vivo therapy. It took a mean of 78.5 +/- 25.4 days to grow sufficient TIL for treatment. Therapy included cyclophosphamide (1 g/m2) on day 1, followed by a 96-hour continuous infusion of IL-2 (18 x 10(6) IU/m2/d) on days 2 to 5, and approximately 10(11) (mean 1.49 +/- 0.93 x 10(11)) TIL on day 2. Patients who responded received monthly IL-2 as a 96-hour infusion. Median patient age was 45 years of age. Sixty-seven percent of the patients were men. Performance status was 0 to 1 in 77% of patients. Thirty-four percent of the patients had liver metastases. The usual IL-2 toxicities were seen. Response rate for 21 patients was 24% (95% confidence interval, 10% to 49%). One complete response was achieved with cells 98% CD4+; four partial responses were achieved with cells 80%, 94%, 98%, and 98% CD8+, respectively. Four of eight patients who received TIL, which had never been stimulated with OKT3, had tumor response. The authors conclude that a treatment plan for IL-2/TIL is technically difficult, costly, and effective for only a minority of patients. Overall, clinical results are not clearly superior to those obtained with other IL-2 regimens.

Adult↗
PubMed1991

Hemodynamic and neurohormonal effects of clonidine in patients with preganglionic and postganglionic sympathetic lesions. Evidence for a central sympatholytic action.

BACKGROUND: Clonidine, a partial presynaptic and postsynaptic alpha-adrenoceptor agonist, has been shown to lower blood pressure in normal subjects but not in tetraplegics; however, the mechanisms of this action have not been elucidated. METHODS AND RESULTS: The hemodynamic and hormonal basis of the hypotensive action of clonidine was investigated in tetraplegics with complete cervical spinal cord transection and preganglionic sympathetic denervation, in patients with unilateral brachial plexus injury and postganglionic sympathetic denervation, and in normal subjects. In normal subjects, the fall in blood pressure after clonidine infusion was accompanied by a reduction in cardiac output that was predominantly due to a fall in stroke volume and in heart rate. The lack of fall in blood pressure, cardiac output, and stroke volume in tetraplegics indicates that these effects are exerted at a supraspinal level and require intact descending sympathetic pathways. After clonidine infusion, digital skin vasodilatation occurred in normal subjects, in the innervated but not the denervated limb of patients with unilateral brachial plexus injury, and in tetraplegics, indicating that this response is due to the central sympatholytic effect of clonidine. Plasma norepinephrine was much lower in tetraplegics compared with normal subjects, and after clonidine infusion, it fell substantially in normal subjects alone. Plasma renin activity did not change. Bladder stimulation in tetraplegics resulted in a rise in blood pressure and vasoconstriction in digital skin vessels. The inability of clonidine to significantly reduce or abolish the pressor and digital vasoconstrictor responses after bladder stimulation in tetraplegics indicates that clonidine does not exert a major effect on spinal preganglionic neurons or peripheral presynaptic alpha 2-adrenoceptors. CONCLUSIONS: Therefore, clonidine is a suitable drug for use in analyzing the central supraspinal levels of control in varying circulatory disorders, such as hypertension and postural hypotension.

Adolescent↗
PubMed1991

Continuous interleukin-2 and lymphokine-activated killer cells for advanced cancer: a National Biotherapy Study Group trial.

We conducted a multicenter, phase II trial of continuous-infusion recombinant interleukin-2 (rIL-2) and lymphokine-activated killer (LAK) cells. Patients had advanced cancer, measurable disease, and a good performance level. Treatment included a 5-day continuous infusion of 18 x 10(6) IU/m2/d of rIL-2 followed by 1 day of rest, 4 days of leukapheresis to collect cells for in vitro augmentation of cellular cytotoxicity, and 5 more days of rIL-2 infusion with reinfusion of LAK cells for 3 successive days. Therapy was repeated after 2 weeks. There were 117 patients enrolled: 63% were males, with a median age of 51 years. Eighty-two percent were managed in oncology units, and 18% were in intensive care units. Six patients died within 1 month of initiating therapy. In renal cell carcinoma, the response rate was one of 31 patients (3%), with a median survival of 10.7 months. In melanoma, the response rate was four of 33 patients (12%), with a median survival of 6.1 months. For all other histologies, response rate was three of 53 patients (5%), with a median survival of 7.4 months. All responders were asymptomatic when therapy was initiated. This trial confirms the feasibility of administering continuous rIL-2 and LAK cells outside the intensive care unit environment. Antitumor activity in melanoma was similar to that seen in multicenter trials of bolus rIL-2 and LAK cells. Activity in renal cell cancer was disappointing.

Adolescent↗
PubMed1991

Repair of median and ulnar nerves. Primary suture is best.

We reviewed, at two to seven years, the results of repair of 108 median and ulnar nerves after clean transection injury between the elbow and wrist in 95 patients ranging in age from 15 to 55 years. Of these, 48 nerves had primary suture, 25 had delayed suture, and 35 were grafted, all repairs being performed by the senior author using standard techniques. Assessment was based on the methods and grading described by Seddon (1975). Thirteen of 60 secondary repairs or grafts failed, but no primary repair failed completely. There were few excellent results; they were found only after primary distal repair in younger patients.

Action Potentials↗
PubMed1991

Iatrogenic injuries of peripheral nerves.

In this study, we discuss 68 cases in which peripheral nerve trunks were inadvertently divided by surgeons. Most of these accidents occurred in the course of planned operations. Delay in diagnosis and in effecting repair was common. We list the nerves particularly at risk and the operations in which special care is needed. We recommend steps to secure prompt diagnosis and early treatment.

Adolescent↗
PubMed1991

Continuous infusion interleukin-2 and tumor-derived activated cells as treatment of advanced solid tumors: a National Biotherapy Study Group Trial.

Metastases from patients with solid tumors were harvested from 196 patients for the purpose of growing tumor-derived activated cells (TDAC). Cells were prepared from autologous tumor cultures by incubation with Interleukin-2 (IL-2) followed by repeated exposure to tumor antigen and/or anti-CD3 monoclonal antibody. Initial growth success was achieved in 66%; 45/56 (80%) of these early cultures were subsequently expanded for in vivo therapy. It took a mean of 69.4 +/- 24.0 days to grow TDAC for treatment. Thirty-eight patients were treated with cyclophosphamide (1 g/m2) on day one followed by a 96-hour continuous infusion of IL-2 (18 x 10(6) IU/m2/day) on days 2-5 and approximately 10(11) TDAC on day 2. Patients subsequently received monthly IL-2 as a 96-hour constant infusion if their cancers were stable or regressing. Median age was 51 yrs; 58% were male. Performance status was 0-1 in 64%, 29% had lung metastases; 34% had liver metastases. The usual IL-2 toxicities were seen. Responses were seen only in 1/38 patients (3%); a partial response in a patient with lymphoma. Forty-two percent were stable 90 days post-treatment, the rest were progressive or inevaluable. We conclude that a treatment plan for IL-2/TDAC is technically difficult, costly, and not practical under these conditions. Clinical results to date are not clearly different than those obtained with other IL-2 regimens.

Adult↗