Search PubMed⌕ Search

Biomedical subjects

A Baker

Publications and source records attributed to A Baker.

At least 217 records · Page 12Linked to original sources
PubMed1984

Sphenoid sinusitis.

We review our clinical experience with infectious sphenoid sinusitis in an effort to characterize the clinical presentation, bacteriology and associated severe complications of this frequently misdiagnosed infection.

Adult↗
PubMed1984

Progressive addition lenses for deaf lip readers and signers.

Deaf patients depend on intermediate vision for interpersonal communication. Deaf presbyopes are at a particular disadvantage since they are usually corrected for near and far vision with bifocals without consideration of their intermediate vision. Progressive addition lenses were used in this study to provide an intermediate correction for a group of deaf presbyopes. The patients' communication ability was tested through Varilux II lenses and habitual bifocals on a series of standardized lip reading and sign language tests. The patients showed better visual communication skills with the progressive adds, a preference for the progressive adds, and the impression of better vision through the progressive addition lens as opposed to their habitual bifocals.

Aged↗
PubMed1983

Prospective randomized evaluation of adjuvant chemotherapy in adults with soft tissue sarcomas of the extremities.

Sixty-five patients with high-grade soft tissue sarcomas of the extremities were treated in a prospective randomized trial evaluating the efficacy of adjuvant chemotherapy with doxorubicin, cyclophosphamide, and high-dose methotrexate. Local therapy was administered using either amputation or wide local resection plus radiation therapy and the chemotherapy was begun in the immediate postoperative period. Actuarial analysis with median follow-up of 653 days revealed an advantage in continuous disease-free and overall survival in the patient group receiving chemotherapy (P = 0.0008 and P = 0.04, respectively, one-sided Mantel-Haenszel test). The continuous disease-free survival at three years is 92% in the chemotherapy group compared to 60% in the no chemotherapy group. Overall survival is 95% and 74% in these two patient groups. Fifty-eight percent of patients had limb-sparing surgery plus radiation therapy and 42% underwent amputation. In both treatment subgroups analyzed separately, chemotherapy resulted in an improvement in disease-free survival compared to randomized controls not receiving chemotherapy (P = 0.006 and P = 0.04 for groups receiving amputation and limb sparing, respectively). There were no local failures in the patients receiving chemotherapy and two local failures in the no chemotherapy group. The results of this trial confirm the historically controlled pilot trial performed in 26 patients between 1975 and 1977. A current update of the patients in the pilot trial, with a minimum four-year follow-up, reveals an improvement in disease-free and overall survival due to chemotherapy (P less than 0.002). Analysis of the previous pilot trial indicates that only few recurrences are seen beyond three years. Thus, it appears that adjuvant chemotherapy should be a part of the treatment adult patients with soft tissue sarcomas of the extremities.

Adult↗
PubMed1983

Use of anti-basement membrane antibodies to distinguish blood vessel capillaries from lymphatic capillaries.

A new method has been developed for identifying blood vessel capillaries and distinguishing them from lymphatic capillaries. Highly purified antibodies to two ubiquitous components of basement membrane--Type IV collagen and laminin--were applied to fresh-frozen and formalin-fixed tissue sections rich in blood vessel capillaries (granulation tissue), rich in lymphatic channels (small intestine and mesentery), and rich in both (skin, lung, and breast). Staining patterns were evaluated using standard immunofluorescence and immunoperoxidase techniques. Blood vessel capillaries contained intact basement membranes with linear staining for both Type IV collagen and laminin. Lymphatic capillaries, in contrast, uniformly lacked immunoreactivity with antibodies to these basement membrane components. These lymphatic capillaries, which were indistinguishable from blood vessel capillaries in both size (cross-sectional area) and shape (vessel eccentricity), were confirmed as lymphatics by dye injection studies. Our immunohistological technique detected 7-10 times more blood vessels than hematoxylin and eosin staining. Both benign and vessels than hematoxylin and eosin staining. Both benign and malignant tumors of blood vessel endothelium including two capillary hemangiomas and two angiosarcomas demonstrated extracellular linear staining for both Type IV collagen and laminin, whereas two lymphangiomas and two lymphangiectasias were negative. This method then provides a sensitive technique for detecting blood vessel capillaries in tissue sections and a reliable means of distinguishing blood vessel capillaries from lymphatic capillaries. This method may also aid in the identification of tumors whose origin is blood vessel endothelium.

Animals↗
PubMed1983

An assessment of the sensitivity of 3 bleeding time techniques.

The sensitivity of 3 bleeding time techniques to an aspirin-induced defect of platelet function has been assessed in 35 normal volunteers. A carefully standardised Ivy technique was compared with 2 commercial devices for a template bleeding time, the Simplate II and the Thrombolette. The standardised Ivy and the Simplate II were found to have a similar sensitivity; the Thrombolette tended to be less sensitive but the difference was not significant.

Aspirin↗
PubMed1982

The treatment of soft-tissue sarcomas of the extremities: prospective randomized evaluations of (1) limb-sparing surgery plus radiation therapy compared with amputation and (2) the role of adjuvant chemotherapy.

Between May 1975 and April 1981, 43 adult patients with high-grade soft tissue sarcomas of the extremities were prospectively randomized to receive either amputation at or above the joint proximal to the tumor, including all involved muscle groups, or to receive a limb-sparing resection plus adjuvant radiation therapy. The limb-sparing resection group received wide local excision followed by 5000 rads to the entire anatomic area at risk for local spread and 6000 to 7000 rads to the tumor bed. Both randomization groups received postoperative chemotherapy with doxorubicin (maximum cumulative dose 550 mg/m2), cyclophosphamide, and high-dose methotrexate. Twenty-seven patients randomized to receive limb-sparing resection and radiotherapy, and 16 received amputation (randomization was 2:1). There were four local recurrences in the limb-sparing group and none in the amputation group (p1 = 0.06 generalized Wilcoxon test). However, there were no differences in disease-free survival rates (71% and 78% at five years; p2 = 0.75) or overall survival rates (83% and 88% at five years; p2 = 0.99) between the limb-sparing group and the amputation treatment groups. Multivariate analysis indicated that the only correlate of local recurrence was the final margin of resection. Patients with positive margins of resection had a higher likelihood of local recurrence compared with those with negative margins (p1 less than 0.0001) even when postoperative radiotherapy was used. A simultaneous prospective randomized study of postoperative chemotherapy in 65 patients with high-grade soft-tissue sarcomas of the extremities revealed a marked advantage in patients receiving chemotherapy compared with those without chemotherapy in three-year continuous disease-free (92% vs. 60%; p1 = 0.0008) and overall survival (95% vs. 74%; p1 = 0.04). Thus limb-sparing surgery, radiation therapy, and adjuvant chemotherapy appear capable of successfully treating the great majority of adult patients with soft tissue sarcomas of the extremity.

Adolescent↗
PubMed1982

Kinetic studies of mouse brain transketolase.

The activity of transketolase in mouse brain was 5.7 nmol/min/mg protein measured by an enzyme-coupled spectrophotometric assay. The apparent Km for ribose-5-phosphate was 330 microM, for D-xylulose-5-phosphate was 120 microM, and for thiamine pyrophosphate was 7 microM. However, thiamine pyrophosphate remained tightly bound to transketolase in homogenates in which it dissociated completely from another thiamine pyrophosphate-dependent enzyme, the pyruvate dehydrogenase complex. These data suggest that loss of transketolase activity is likely to be a later consequence of thiamine deficiency in mammalian brain than is decreased activity of pyruvate dehydrogenase complex.

Animals↗
PubMed1980

Effect of nutritional and enzymatic methionine deprivation upon human normal and malignant cells in tissue culture.

Human embryonic lung fibroblasts (F-136-35-56) capable of growing in medium containing DL-homocysteine instead of L-methionine and human acute lymphoblastic leukemia cells (CCRF-HSB-2) with absolute methionine requirement exhibited dose-dependent growth inhibition when semipurified L-methionine-degrading enzyme (L-methioninase, EC 4.4.1.11) was added to the tissue cultures. When D-homocystine was added to the cultures together with L-methioninase (0.1 units/ml, which completely degraded the available L-methionine in tissue culture), the F-136-35-56 cells continued to grow whereas the CCRF-HSB-2 cells were completely inhibited. In mixed cultures of the two cell lines with added L-methioninase + D-homocystine or L-methioninase + L-homocysteine thiolactone, the normal fibroblasts grew and synthesized DNA vigorously, whereas the lymphocytic malignant cells lost their viability completely and died within 3 to 4 days.

Carbon-Sulfur Lyases↗
PubMed1978

"Hand gym" for patients with arthritic hand disabilities: preliminary report.

To improve function and to delay the tendency toward deformities of the rheumatoid arthritic hand, a new device was evaluated which enables patients to perform range of motion and isometric exercises in their home. Eighteen patients (35 hands) exercised daily for four months. Strength and range of motion showed statistically significant gains. Grip strength increased in 28 hands, volar pinch in 22 hands, lateral pinch in 21 hands. Of 140 PIP joints, 77% increased in range, indicating loosening of intrinsic muscles. Improvement in hand function was reported by most of the patients.

Activities of Daily Living↗
PubMed1973

Alkaline phosphatase. Possible induction by cyclic AMP after cholera enterotoxin administration.

The present studies were undertaken to determine the role, if any, of cyclic 3',5'-adenosine monophosphate (cyclic AMP) as a chemical inducer of rat liver alkaline phosphatase. Cholera enterotoxin, given intravenously to rats, led to a rapid rise in the activity of hepatic adenyl cyclase that was 7(1/2) times greater than control values in 6 h. Cyclic AMP levels were also significantly increased above control values while the activity of cyclic nucleotide phosphodiesterase was unchanged. Hepatic alkaline phosphatase activity was increased 5(1/2) times above control in 12 h, but its rise followed that of adenyl cyclase and cyclic AMP by several hours. Cycloheximide inhibited the rise of hepatic alkaline phosphatase but not that of adenyl cyclase. The administration of glucagon, a known stimulator of hepatic adenyl cyclase, and of dibutyryl cyclic AMP, led to similar striking increases in hepatic alkaline phosphatase activity. This alkaline phosphatase increase was blocked by the prior administration of cycloheximide. Bile duct ligation, a known stimulator of hepatic alkaline phosphatase activity, failed to produce any significant changes in adenyl cyclase or cyclic AMP. Concomitant treatment of rats with bile duct ligation and cholera enterotoxin or bile duct ligation and glucagon, had no additive effect on the increase in hepatic alkaline phosphatase activity, although the increase occurred earlier. These results suggest that: (a) cyclic AMP may act as an inducer of hepatic alkaline phosphatase: (b) the stimulation of hepatic alkaline phosphatase by cholera enterotoxin is mediated by cyclic AMP; (c) the rise in hepatic alkaline phosphatase following bile duct ligation is not mediated by cyclic AMP; (d) the same alkaline phosphatase in rat liver may be induced by two (or more) mechanisms, only one of which requires cyclic AMP.

Adenylyl Cyclases↗