Search PubMed⌕ Search

Biomedical subjects

J Frankel

Publications and source records attributed to J Frankel.

At least 37 records · Page 2Linked to original sources
PubMed1994

Preoperative 5-fluorouracil, low-dose leucovorin, and concurrent radiation therapy for rectal cancer.

BACKGROUND: A Phase I trial was performed to determine the maximum tolerated dose of concurrent preoperative radiation therapy (5040 cGy) and 2 cycles (bolus daily times 5) of 5-fluorouracil (5-FU) and low-dose leucovorin (LV) (20 mg/m2), followed by surgery and 10 cycles of postoperative 5-FU/LV in patients with primary or recurrent rectal cancer. METHODS: Twenty-four patients were entered into the study. Preoperatively, the initial dose of 5-FU was 325 mg/m2. 5-FU was escalated 50 mg/m2, while the dose of LV and radiation therapy remained constant. Chemotherapy and radiation began concurrently on day 1. The postoperative chemotherapy was not dose escalated; 5-FU, 425 mg/m2, and LV, 20 mg/m2. The median follow-up was 10 months (range, 4-19 months). RESULTS: The resectability rate with negative margins in the 23 patients who underwent surgery was 100%. One patient refused surgery. The pathologic complete response rate was 13% (3 of 23). An additional four patients had negative nodes and a microscopic foci of tumor in the bowel wall. Therefore, the total clinical complete response rate was 30% (7 of 23). The maximum tolerated dose of 5-FU for the preoperative combined modality segment was 375 mg/m2; therefore, the recommended Phase II dose level is 325 mg/m2. The incidence of Grade 3+ toxicity for the 22 patients treated at the recommended 5-FU dose level (325 mg/m2) during the preoperative combined modality segment was as follows: diarrhea, 14%; erythema, 5%; hematologic, 10%; and total, 18%. The median nadir counts were leukocyte count, 3.7 (range, 1.5-5.9); hemoglobin count, 12.2 (range, 10.2-14.3); and platelet count (times 1000), 165 (range, 92-237). CONCLUSIONS: With this regimen, the recommended doses of chemotherapy in the combined modality segment are slightly higher than those recommended in arm 2 of the Intergroup postoperative adjuvant rectal trial 0114. This regimen will serve both as the preoperative arm of the Intergroup randomized trial of preoperative versus postoperative combined modality therapy for resectable rectal cancer (INT R9401) as well as the basis for the combined modality segment of NSABP RO-3.

Adenocarcinoma↗
PubMed1994

Total lymphoid irradiation in multiple sclerosis.

Following a report of the efficacy of total lymphoid irradiation (TLI) in the treatment of chronic progressive multiple sclerosis a further randomised double-blind placebo-controlled study was undertaken with the intention of entering 56 patients. In the event it was possible to recruit only 27 patients in a 2.5 year period. Three patients received active treatment openly and 24 were randomised to either active (14) or sham (10) treatment. Treatment was 1980 cGy to the lymphoid system and spleen or sham treatment after full simulation. The primary outcome measure was a comparison of the mean rates of change between treatment groups on the expanded Kurtzke disability scale (EDSS) over the two year follow up period. Patients were also assessed on other clinical outcome measures, psychometry, and serial MRI of the brain. Active treatment resulted in a profound and prolonged fall in T lymphocytes especially those with the CD4 marker and a reversal in CD4:CD8 ratio. No significant benefit was demonstrated on the rate of clinical disease progression (EDSS). A small but significant benefit was found on a score of bladder function. No significant benefit was demonstrated on other clinical or psychometric indices or on subjective visual analogue scales. There was a small but significant difference in the rate of accumulation of lesions on brain MRI favouring the treatment group. The treated group had a higher incidence of clinically relevant side effects, notably amenorrhoea and infections: three deaths (one in the TLI group, two in the sham treated group) occurred. A post hoc calculation indicates that the study had a possible 35% risk of a false negative result using the principal outcome measure. The study fails to confirm the previously reported clinical benefit of TLI although there may be a minor benefit on disease progression as indicated by MRI lesion counts. It is concluded that TLI cannot be recommended for the routine treatment of chronic progressive multiple sclerosis but the beneficial effect on MRI lesions, though modest, suggests that further research into immune modulation of this condition may be worthwhile.

Adult↗
PubMed1993

The efficacy of preoperative 5-fluorouracil, high-dose leucovorin, and sequential radiation therapy for unresectable rectal cancer.

BACKGROUND: The encouraging results seen in patients who received postoperative combined modality therapy in the adjuvant setting have prompted increased interest in preoperative combined modality therapy for patients with unresectable rectal cancer. The authors report the local control and survival of a previously reported Phase I dose escalation trial of combined preoperative 5-fluorouracil (5-FU), high-dose leucovorin (LV), and sequential radiation therapy followed by postoperative LV-5 FU for the treatment of patients with unresectable rectal cancer. METHODS: Twenty patients (13, primary and 7, recurrent disease) received LV-5-FU for one cycle. Radiation therapy (5040 cGy) began on day 8. A second cycle of LV-5-FU was given concurrently with week 4 of radiation. Six patients received intraoperative brachytherapy. Postoperatively, the patients received LV-5-FU. The pathologic complete response rate was 20%, and 89% underwent a complete resection with negative margins. RESULTS: The crude local failure rate was 26%, and the 3-year actuarial local failure rate was 29% (95% confidence interval [CI], +/- 8.94%). The crude abdominal and distant failure rates were 40% and 30%, respectively. The 3-year actuarial disease-free survival was 64% (95% CI, +/- 6.75%), and the overall survival was 69% (95% CI, +/- 7.65%). CONCLUSIONS: These preliminary data revealed encouraging local control and survival rates. Preoperative combined modality therapy is an attractive approach in patients with unresectable rectal cancer.

Aged↗
PubMed1993

Pre-operative combined 5-FU, low dose leucovorin, and sequential radiation therapy for unresectable rectal cancer.

PURPOSE: We performed a Phase I trial to determine the maximum tolerated dose of combined pre-operative radiation (5040 cGy) and 2 cycles (bolus daily x 5) of 5-FU and low dose LV (20 mg/m2), followed by surgery and 10 cycles of post-operative LV/5-FU in patients with unresectable primary or recurrent rectal cancer. METHODS AND MATERIALS: Twelve patients were entered. The initial dose of 5-FU was 325 mg/m2. 5-FU was to be escalated while the LV remained constant at 20 mg/m2. Chemotherapy began on day 1 and radiation on day 8. The post-operative chemotherapy, was not dose escalated; 5-FU: 425 mg/m2 and LV: 20 mg/m2. The median follow-up was 14 months (7-16 months). RESULTS: Following pre-operative therapy, the resectability rate with negative margins was 91% and the pathologic complete response rate was 9%. For the combined modality segment (preoperative) the incidence of any grade 3+ toxicity was diarrhea: 17%, dysuria: 8%, mucositis: 8%, and erythema: 8%. The median nadir counts were WBC: 3.1, HGB: 8.8, and PLT: 153,000. The maximum tolerated dose of 5-FU for pre-operative combined LV/5-FU/RT was 325 mg/m2 with no escalation possible. Therefore, the recommended dose was less than 325 mg/m2. CONCLUSIONS: Since adequate doses of 5-FU to treat systemic disease could not be delivered until at least 3 months (cycle 3) following the start of therapy, we do not recommend that this 5-FU, low dose LV, and sequential radiation therapy regimen be used as presently designed. However, given the 91% resectability rate we remain encouraged with this approach.

Adult↗
PubMed1993

Hypoangular: a gene potentially involved in specifying positional information in a ciliate, Tetrahymena thermophila.

In Tetrahymena, two unique cell-surface structures, the oral apparatus and the cytoproct, are formed at opposite ends of one ciliary row, the reference meridian, which is propagated longitudinally during clonal growth. A third set of unique structures, the contractile vacuole pore(s) (CVP), is located at a nearly constant proportion of the cell circumference to the cell's right of the reference meridian. Three allelic recessive temperature-sensitive mutations, collectively named hypoangular (hpo), alter both the geometry of propagation of the reference meridian and the location of the CVPs. In mutant cells, the reference meridian typically undergoes a steady rightward shift in successive cell generations ("cortical slippage"); concomitantly, CVP sets come to lie closer to the reference meridian. Although CVP location is still proportional to the cell circumference, the constant of proportionality (the "CVP angle") is reduced. Another effect is an alteration in the widths of morphogenetic domains within the cortex. As the temperature is raised (made more restrictive), these effects are accentuated and the CVP angle becomes reduced further. At the extreme, the CVP angle collapses to zero and less, i.e., there is a topological switch such that CVPs come to lie to the left of the reference meridian, and the direction of cortical slippage reverses from rightward to leftward. These observations are hard to reconcile with existing formal models of pattern specification in this system and suggest that the hpo locus might specify a key component of the intracellular positional system.

Alleles↗
PubMed1992

Genes and structural patterns in ciliates: Vance Tartar and the "cellular architects".

The one form of cytoplasmic inheritance that has not been assimilated into the Central Dogma is the inheritance of surface structural patterns, a phenomenon most clearly expressed in ciliates. Vance Tartar, although he worked with a genetically undomesticated organism (Stentor coeruleus), provided early evidence for the crucial role of clonally propagated features of the cell cortex. He showed that the capacity for development of cortical organelle systems is associated with a particular relational feature, the "locus of stripe contrast" (LSC), and that clonally inherited cortical variants (homopolar doublets) could be created at will by microsurgical operations that duplicated the LSC. Tartar also hoped to demonstrate the existence of what David Nanney called "cellular architects" by provoking stentors to carry out entirely novel types of morphogenetic performances. He eventually acknowledged failure, although the bizarre juxtapositions by which he attempted to elicit such novel performances did bring about specific and illuminating defects in cortical development. Subsequent analyses of similar defects in other ciliates revealed not the unitary "pattern factor" postulated by Tartar, but rather a hierarchy of distinct patterning mechanisms. Nonetheless, by pursuing an embryological approach toward morphogenesis in a highly regulative ciliate, Tartar uncovered relational aspects of pattern-determination; this, in my view, delineates the major problem that we must solve to gain understanding of intracellular patterning.

Animals↗
PubMed1992

Phase I trial of postoperative 5-FU, radiation therapy, and high dose leucovorin for resectable rectal cancer.

Following surgery for Stages T3-4N0-2M0 primary and recurrent resectable rectal cancer limited to the pelvis, 25 patients have been entered on a Phase I trial of pelvic radiation therapy (RT) [5040 cGy] and 12 cycles of postoperative 5-FU and high dose Leucovorin (LV) chemotherapy. 5-FU was escalated 50 mg/m2 while the LV remained constant at 200 mg/m2. The initial doses of 5-FU were: combined-RT/chemotherapy = 200 mg/m2 and post-RT chemotherapy = 325 mg/m2. The median F/U was 25 months (range: 13-36). Two maximum tolerated doses (MTD's) have been determined, one for combined-RT/chemotherapy and one for post-RT chemotherapy. The MTD for combined-RT/chemotherapy was 250 mg/m2; therefore, the recommended dose of 5-FU is 200 mg/m2. The MTD for post-RT chemotherapy was 375 mg/m2; therefore, the recommended dose of 5-FU is 325 mg/m2. The dose limiting toxicities were diarrhea, tenesmus, frequent bowel movements, dysuria, and myelosuppression. For the nine patients who received 5-FU at the recommended dose level the median low counts were WBC 3.5 (2.2-4.0), HGB 10.3 (9.0-12.3), and PLT (x 1000) 167 (133-280), and the incidence of any grade greater than or equal to 3 toxicity was 22% diarrhea, 17% tenesmus, and 22% frequent bowel movements. The recommended dose of combined-RT/chemotherapy as used in this protocol was relatively well tolerated. However, optimal doses of 5-FU cannot be delivered until the fourth postoperative month. Therefore, despite the encouraging results reported with high dose LV in patients with advanced disease, we do not recommend that high dose LV be used with combined RT and 5-FU in the treatment regimen as presently designed.

Adenocarcinoma↗
PubMed1992

Positional information in cells and organisms.

The processes of pattern formation are usually considered to be quite different in unicellular and multicellular organisms. The only unifying ideas have been very general, such as those concerning regional differences and organization along a polar axis. Concepts like induction, fields and gradients have generally been applied only to the development of multicellular organisms. Here, Joseph Frankel suggests that pattern formation by multicellular organisms evolved in their progenitors in response to multiplication of cytoplasmic structural units rather than of nuclei. Ciliates provide a living example of complex patterning in a compound uninucleate organism.

Journal Article↗
PubMed1992

Enhancement of radiation-induced downstaging of rectal cancer by fluorouracil and high-dose leucovorin chemotherapy.

PURPOSE: To determine if fluorouracil (5-FU) plus high-dose leucovorin (LV) enhances local response in patients receiving preoperative radiation therapy (RT) for adenocarcinoma of the rectum, we compared the degree of downstaging in patients receiving preoperative RT with or without chemotherapy. PATIENTS AND METHODS: For this comparison, three groups of patients who were treated with identical doses and techniques of preoperative pelvic RT (total dose of 5,040 cGy) were examined. Group 1 included 20 patients with unresectable disease who received combined RT and LV/5-FU. Group 2 included 11 patients with unresectable disease who received preoperative RT. Group 3 included 21 patients with invasive, resectable, primary disease who received preoperative RT. RESULTS: Patients with unresectable disease who received LV/5-FU had a higher rate of pathologic complete response (20% v 0%) and a lower incidence of positive nodes (30% v 64%) compared with those who did not receive chemotherapy. Even when the most favorable group of patients was included (group 3), patients who received LV/5-FU still had a higher complete response rate (20% v 6%) and a lower incidence of positive nodes (30% v 53%) compared with those who received RT without LV/5-FU. Of those patients with initially unresectable disease, the resectability rate was higher in those who received LV/5-FU compared with those who did not receive LV/5-FU (90% v 64%). Patients who received LV/5-FU experienced slightly more grade 1 to 2 fatigue, stomatitis, nausea, and grade 3 diarrhea, tenesmus, and dysuria. CONCLUSIONS: Despite the fact that patients who received chemotherapy (group 1) had more advanced disease compared with those with resectable disease (group 3), the addition of LV/5-FU increased the resectability and downstaging rates. The ultimate impact of a complete response as well as a decrease in the incidence of pelvic nodes on local control and survival remains to be determined. However, given the enhancement of down-staging in patients with unresectable rectal cancer, we are encouraged by the combined modality approach.

Adenocarcinoma↗
PubMed1992

Combined modality therapy of rectal cancer: decreased acute toxicity with the preoperative approach.

PURPOSE: We compared the combined radiation therapy (RT) plus chemotherapy segments of two separate parallel phase I trials to determine if combined pelvic RT, fluorouracil (5-FU), and high-dose leucovorin (LV) had less acute toxicity when delivered preoperatively versus postoperatively in patients with rectal cancer. PATIENTS AND METHODS: Patients with unresectable disease received preoperative RT plus LV and 5-FU followed by surgery and postoperative LV and 5-FU. Patients with resectable disease received identical doses, techniques, and schedules of RT and LV and 5-FU except all therapy was delivered postoperatively. On day 1, patients received LV and 5-FU times one cycle. RT began on day 8. A second cycle of LV and 5-FU was given concurrently with the fourth week of RT. RESULTS: Although more patients (75% v 32%; P = .02) received the higher dose level of 5-FU (250 mg/m2), significantly fewer experienced acute grade 3 to 4 toxicity with preoperative versus postoperative therapy (13% v 48%; P = .045). There was no grade 3 to 4 myelosuppression in either group. The two grade 3 toxicities in the preoperative group were gastrointestinal. The grade 3 toxicities in the postoperative group included seven gastrointestinal and two genitourinary; four patients had a grade 4 toxicity. CONCLUSION: Given the high incidence of grade 3 to 4 toxicity also reported in the postoperative combined modality adjuvant randomized trials, future adjuvant trials should explore the preoperative approach.

Adult↗
PubMed1991

Preoperative high-dose leucovorin/5-fluorouracil and radiation therapy for unresectable rectal cancer.

Twenty patients with primary or recurrent unresectable rectal cancer limited to the pelvis were entered on a Phase I trial of preoperative pelvic radiation therapy (RT) (5040 cGy) and two cycles of combined high-dose leucovorin (LV) and 5-fluorouracil (5-FU), followed by surgery and ten cycles of postoperative LV/5-FU (sequential). Maximum tolerated doses (MTD) were determined for preoperative combined LV/5-FU and RT and for postoperative sequential LV/5-FU. 5-FU was escalated 50 mg/m2 while the LV remained constant at 200 mg/m2. The initial doses of 5-FU were combined LV/5-FU and RT (200 mg/m2) and sequential LV/5-FU (325 mg/m2). The median follow-up time was 14 months. The resectability rate was 89%, and the pathologic complete response rate was 21%. The MTD for combined LV/5-FU and RT was 300 mg/m2; therefore, the recommended dose of 5-FU is 250 mg/m2. The recommended dose of 5-FU for sequential LV/5-FU is 375 mg/m2. The dose-limiting toxicities in this trial were diarrhea, tenesmus, increased bowel movements, dysuria, and myelosuppression. For the six patients who received 5-FU at the recommended dose level, the median low counts were leukocyte count, 3.7/microliters (range, 2.4 to 4.9/microliters); hemoglobin, 9.0 g/dl (range, 8.2 to 11.9 g/dl); and platelet count (X1000), 146/microliters (range, 89 to 182/microliters). The incidence rate of any Grade 3 toxicity was 17% (diarrhea and frequent bowel movements). The recommended doses of 5-FU used in this protocol were well tolerated. Because there was a long delay before optimal doses of 5-FU could be delivered, the authors do not recommend that high-dose LV be used in conjunction with combined 5-FU and RT with the treatment regimen as currently designed. However, because the resectability and complete response rates were higher than those previously reported for preoperative RT alone, the authors are encouraged by the combined technique approach. New trials are currently being undertaken to determine if the use of a low-dose LV regimen is more tolerable.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Intracellular handedness in ciliates.

Ciliated protozoa have intrinsically asymmetrical ciliary structures that are asymmetrically arranged over the cell surface. These structures can be arranged in two enantiomorphic configurations, 'right-handed' (RH) and 'left-handed' (LH). Whereas one of these configurations (arbitrarily, RH) is apparently universal in Nature and predominant in the laboratory, mirror-image (RH-LH) doublets and reverse (LH) singlets have been generated and studied in eight different ciliate genera. In all these, the internal asymmetry of individual ciliary structures remains normal even when the asymmetry of arrangement of these structures is reversed. The individual structures may sometimes become inverted (rotationally permuted). LH forms reproduce themselves if they are able to feed, or reorganize periodically before starving to death if they are not. Changes of cellular handedness depend upon unusual geometric configurations and in most cases are unrelated to genic changes. In hypotrich ciliates changes of handedness can be provoked by artificially generated juxtapositions of anterior and posterior cell regions or of right and left cell margins. Reversal of handedness in ciliates can be visualized as a consequence of (re-)establishment of a normal sequence of normally spaced positional values following geometric disturbances created by the experimenter or by the regulating cell.

Animals↗
PubMed1991

Conjugal blocks in Tetrahymena pattern mutants and their cytoplasmic rescue. II. janus A.

A conjugal block phenotype is described for the Tetrahymena pattern mutant, janA. janA exhibits a characteristic "janus" phenotype in which cells develop with a global mirror-image duplication of the ventral pattern of cortical organelles. janA cells are competent to form mating pairs, but later become irreversibly fused as heteropolar doublets. The few pairs that successfully dissociate fail to undergo postconjugal oral replacement and perish. The janA conjugal block is 100% penetrant, is under prezygotic macronuclear control, and is lethal. Here we characterize this conjugal block genetically and cytologically and demonstrate that it can be rescued by a transferable, wild-type product. New insights into late conjugal events, especially the replacement of the oral apparatus, are reported for wild-type cells as well.

Animals↗
PubMed1991

Microsurgically generated discontinuities provoke heritable changes in cellular handedness of a ciliate, Stylonychia mytilus.

Stylonychia mytilus is a dorsoventrally flattened ciliate with compound ciliary structures arranged in a specific manner on the cell surface. In mirror-image (MI) doublets of this ciliate, two nearly complete sets of ciliary structures are arrayed side-by-side, one in a normal or 'right-handed' (RH) arrangement, the other in a reversed or 'left-handed' (LH) arrangement. MI-doublets exist in two forms, one with the RH component on the right, the LH component on the left, and feeding structures near the center ('buccal-adjoining MI-doublet'); the other with the RH component on the left, the LH component on the right, and feeding structures on the lateral edges ('buccal-opposing MI-doublet'). We describe an operation that can generate either type of MI-doublet. This operation interchanges large anterior and posterior regions of the cell, transposing the original posterior region anteriorly (P----A) and the original anterior region posteriorly (A----P), while retaining the original anteroposterior polarity of each region. Two sets of new ciliary structures then are formed in mirror-image arrangement, with the set in the P----A region oriented normally and the set in the A----P region undergoing a reversal of polarity along its anteroposterior axis. This sometimes creates end-to-end MI forms, but more commonly produces side-by-side MI-doublets through a folding together of the P----A and A----P regions. This folding occurs because one lateral edge of the cell had been removed during the operation; if the left edge was removed, the complex folds to the left and forms a buccal-adjoining MI-doublet, whereas if the right edge was removed, the complex folds to the right and forms a buccal-opposing MI-doublet. Both types can reorganize and later divide true-to-type, although the 'buccal-opposing' type is by far the more stable of the two. The generation of mirror-image forms is dependent on the prior abnormal juxtaposition of regions from opposite ends of the cell, and involves a coordinated respecification of large-scale organization. We interpret this response to be a consequence of intercalation of missing intervening positional values in the zone of posterior-anterior abutment.

Animals↗
PubMed1991

Learning style preferences: a comparison of younger and older adult females.

This study explored the learning styles of older adult females (65 + years) as compared to younger adult females (35-55 years) in the areas of immediate environment, emotionality, sociological needs and physical needs. At recreation community centers, 80 subjects were selected on a non-random basis, with one-half falling in each age category. Each subject was individually questioned using the Productivity Environmental Preference Survey, which analyzes a personal preference for each of 20 elements and identifies how adults prefer to function, learn, concentrate and perform in their educational or occupational activities. An analysis by t test showed a significant difference between the two groups in the elements of light, learning alone--peer oriented, authority figures present, and evening--morning. When the elements were combined and treated by discriminant analysis, most of these findings were confirmed, showing a significant difference in five elements: light, motivation, responsibility, learning alone--peer oriented, evening--morning. These findings might be useful to nutrition educators when developing nutrition programs for the elderly.

Adult↗
PubMed1991

Complications of calcaneal osteotomies.

This article describes the associated complications encountered with calcaneal osteotomies. The paper stresses the importance of preoperative evaluation, surgical technique, and postoperative care. We also emphasize the triplanar nature of calcaneal deformities that calcaneal osteotomies correct.

Calcaneus↗