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Abstract
Formation of th neuromuscular junction depends upon reciprocal inductive interactions between the developing nerve and muscle, resulting in the precise juxtaposition of a differentiated nerve terminal with a highly specialized patch on the muscle membrane, termed the motor endplate. Agrin is a nerve-derived factor that can induced molecular reorganizations at the motor endplate, but the mechanism of action of agrin remains poorly understood. MuSK is a receptor tyrosine kinase localized to the motor endplate, seemingly well positioned to receive a key nerve-derived signal. Mice lacking either agrin or MuSK have recently been generated and exhibit similarly profound defects in their neuromuscular junctions. Here we demonstrate that agrin acts via a receptor complex that includes MuSK as well as a myotube-specific accessory component.
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53
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Formulation and antitumor activity evaluation of nanocrystalline suspensions of poorly soluble anticancer drugs. Pharm Res 1996; 13:272-8. [PMID: 8932448 DOI: 10.1023/a:1016051316815] [Citation(s) in RCA: 136] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE Determine if wet milling technology could be used to formulate water insoluble antitumor agents as stabilized nanocrystalline drug suspensions that retain biological effectiveness following intravenous injection. METHODS The versatility of the approach is demonstrated by evaluation of four poorly water soluble chemotherapeutic agents that exhibit diverse chemistries and mechanisms of action. The compounds selected were: piposulfan (alkylating agent), etoposide (topoisomerase II inhibitor), camptothecin (topoisomerase I inhibitor) and paclitaxel (antimitotic agent). The agents were wet milled as a 2% w/v solids suspension containing 1% w/v surfactant stabilizer using a low energy ball mill. The size, physical stability and efficacy of the nanocrystalline suspensions were evaluated. RESULTS The data show the feasibility of formulating poorly water soluble anticancer agents as physically stable aqueous nanocrystalline suspensions. The suspensions are physically stable and efficacious following intravenous injection. CONCLUSIONS Wet milling technology is a feasible approach for formulating poorly water soluble chemotherapeutic agents that may offer a number of advantages over a more classical approach.
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Prognostic value of histological grading in ductal adenocarcinoma of the pancreas. Klöppel vs TNM grading. INTERNATIONAL JOURNAL OF PANCREATOLOGY : OFFICIAL JOURNAL OF THE INTERNATIONAL ASSOCIATION OF PANCREATOLOGY 1995; 17:279-89. [PMID: 7642975 DOI: 10.1007/bf02785825] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A new histological grading system with prognostic correlation for pancreatic cancer was proposed by Klöppel et al. in 1985. Histological sections from 60 ductal adenocarcinomas operated on between January 1980 and December 1990 were retrospectively reviewed in order to compare Klöppel's grading with standard TNM's grading and assess their prognostic value. Klöppel grading was determined through the following histologic and cytologic factors: number duct-like structures, mucus production, neoplastic epithelium, arrangement and pleomorphism of nuclei, and mitotic activity. A score from 0 (well differentiated) to 2 (poorly differentiated) was given to each factor. The mean value obtained dividing the sum of the different values by the number of parameters was used to construct a malignancy scale and therefore allocate each patient to his Klöppel grading. The concordance index K between the two grading systems was relevant (K = 0.85 p < 0.001). There was no relation either between gradings (Klöppel or TNM) and preoperative duration of symptoms or between gradings and UICC stages. TNM's G2 grades of malignancy, N status, and tumor stage were significantly related to survival time (p < 0.05). Klöppel's grading does not show any advantage over the classical and simpler TNM's grading, even though it can be considered more objective and therefore more easily reproducible. This characteristic further should be enhanced by the introduction of a malignancy scale such as the "mean value."
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55
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The anticoagulation factor protein S and its relative, Gas6, are ligands for the Tyro 3/Axl family of receptor tyrosine kinases. Cell 1995; 80:661-70. [PMID: 7867073 DOI: 10.1016/0092-8674(95)90520-0] [Citation(s) in RCA: 550] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We report the identification of ligands for Tyro 3 (alternatively called Sky, rse, brt, or tif) and Axl (alternatively, Ark or UFO), members of a previously orphan family of receptor-like tyrosine kinases. These ligands correspond to protein S, a protease regulator that is a potent anticoagulant, and Gas6, a protein related to protein S but lacking any known function. Our results are reminiscent of recent findings that the procoagulant thrombin, a protease that drives clot formation by cleaving fibrinogen to form fibrin, also binds and activates intracellular signaling via a G protein-coupled cell surface receptor. Proteases and protease regulators that also activate specific cell surface receptors may serve to integrate coagulation with associated cellular responses required for tissue repair and growth, as well as to coordinate protease cascades and associated cellular responses in other systems, such as those involved in growth and remodeling of the nervous system.
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56
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[Multifocal Langerhans cell granulomatosis. Report of a clinical case]. Minerva Med 1994; 85:413-6. [PMID: 7936361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Langerhans' cell granulomatosis is a rare disease whose incidence on adults is valued about one case out of 3.000.000. The multifocal form is rarer than the single eosinophilic granuloma of the bone. It mainly affects males during childhood and it is usually localized in the long bones, hands, feet, and in the skull. We present the case of a young woman affected by multifocal Langerhans cell granulomatosis with bones and skin involved. Unusual in the presented clinical case is the age in which the disease come out. There is the highest incidence of multifocal lesions during childhood, while the monofocal kind is more typical of the years of adult age. Bone localization in the sternum is also quite unusual. In fact it is impossible to find reports of it in recent literature. As the patient refused to undergo chemotherapy she was treated with radiant therapy as for as bone localization concerned and with mecloretamin for local administration on skin lesion. Eleven months after the diagnosis we have not noticed the appearance of new lesions.
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Physical medicine and its relationship to patient management. Clin Podiatr Med Surg 1993; 10:271-83. [PMID: 8481883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this article, some general concerns for the use of modalities and procedures for the older person are given. Management of the geriatric patient requires knowledge, understanding, and patience; it requires a clinician and health care staff that care about older people. It requires a recognition of the dignity of age and the intrinsic worth of each individual as a human being. It requires hope and an ability to project a quality of life, regardless of the living condition. It requires kind words and a hands-on effort. It requires an appreciation of life and a high degree of ethical and moral concern.
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Europium(III) luminescence and tyrosine to terbium(III) energy-transfer studies of invertebrate (octopus) calmodulin. Biochemistry 1992; 31:7016-26. [PMID: 1643036 DOI: 10.1021/bi00146a002] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effects of minor differences in the amino acid sequences between a vertebrate (bovine testes) and an invertebrate (octopus) calmodulin on metal ion binding were investigated via laser-induced Eu3+ and Tb3+ luminescence. Amino acid substitutions at residues which are coordinated to the metal ion do not produce any detectable changes in the 7F0----5D0 excitation spectrum of the Eu3+ ion bound to octopus calmodulin relative to bovine testes calmodulin; only minor differences in the excited-state lifetime values in D2O solution are observed. The dissociation constants for Eu3+ (1.0 +/- 0.2 microM) and Tb3+ (5 +/- 1 microM) from the weak lanthanide binding sites (III and IV, numbered from the amino terminus) of octopus calmodulin were measured using luminescence techniques. Both values agree well with those reported previously for bovine testes calmodulin [Mulqueen, P. M., Tingey, J. M., & Horrocks, W. D., Jr. (1985) Biochemistry 24, 6639-6645]. The measured dissociation constant of Eu3+ bound in the tight lanthanide binding sites (I and II) is 6 +/- 2 nM for octopus calmodulin and 12 +/- 2 nM for bovine testes calmodulin. The distances between sites I and II (12.4 +/- 0.5 A) and sites III and IV (11.7 +/- 0.8 A) were determined from Förster-type energy transfer in D2O solutions of octopus calmodulin containing bound Eu3+ donor and Nd3+ acceptor ions. Förster theory parameters for nonradiative energy transfer between Tyr138 and Tb3+ ions bound at sites III and IV of octopus calmodulin were comprehensively evaluated, including a dynamics simulation of the orientation factor kappa 2. This theory is found to account quantitatively for the observed energy-transfer efficiency as evaluated from the observed sensitized Tb3+ emission.
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Surgery plus adjuvant chemotherapy for T1-3N0M0 small-cell lung cancer. Rationale for current approach. Am J Clin Oncol 1991; 14:218-24. [PMID: 1851603 DOI: 10.1097/00000421-199106000-00008] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Between January 1980 and December 1986, 42 patients with histological confirmed small-cell lung cancer (SCLC) staged pathologically as T1-3N0M0 disease entered a prospective study of surgery plus adjuvant chemotherapy including six courses of i.v. cyclophosphamide (1 g/m2, day 1), epirubicin (60 mg/m2, day 1), and etoposide (120 mg/m2, days 1, 3, and 5), at 3-week intervals. No thoracic or prophylactic cranial irradiation was given. With a 52.5-month median follow-up, estimated 5-year survival was 36% and median survival was 32.7 months (range, 5-100+) for all patients. Seven patients (17%) are currently alive and disease-free at 63 to 100 months. In univariate analysis, baseline characteristics significantly influencing survival and disease-free interval (DFI) were the tumor stage (T1 and T2 versus T3), tumor histology (oat and intermediate versus combined cell type), and type of resection (lobectomy versus pneumonectomy). However, in multivariate analysis, only the tumor stage (T1-2 versus T3) maintained its level of significance. There was a significant correlation (p less than 0.0001) between the pathological tumor size (maximum tumor diameter [(MTD) cm] and survival and DFI; once the MTD (less than versus greater than median value, 3.9 cm) was included in univariate and multivariate analysis, the tumor stage no longer appeared to maintain its level of significance. Treatment was generally well-tolerated and toxicity was acceptable. This study demonstrates the effectiveness of surgery and adjuvant chemotherapy in yielding impressive long-term survival for T1 and T2N0M0 SCLC and provides evidence that the MTD can be used as a powerful and independent prognostic factor for stratification of patients in further trials.
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60
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Adjuvant chemotherapy for T1-2NOMO small cell lung cancer: single-agent or combination chemotherapy? Cancer Invest 1991; 9:19-25. [PMID: 1849442 DOI: 10.3109/07357909109032796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In an attempt to address the schedule of adjuvant chemotherapy in surgically resected T1 or T2NOMO small cell lung cancer, 12 patients were randomized to receive 6 courses of either single-agent (high-dose epirubicin) or combination (cyclophosphamide, epirubicin, and etoposide) chemotherapy, at 3-week intervals. No thoracic radiotherapy was administered while prophylactic cranial irradiation (30 Gy/10 fractions/2 weeks) was given. With a 25-month median followup, overall estimated 2-year and median survival were 83% and 26.5 months (range 16-34+), respectively. Ten patients are currently alive and disease free. No significant difference in 2-year survival was observed between the two adjuvant treatment modalities and median survival was 28 months (range 13-34+) for combination and 21 months (range 14-29+) for single-agent chemotherapy. Although at high doses, epirubicin resulted in a moderate clinical and histological cardiotoxicity and a remarkably reduced incidence of severe (WHO grades 3 and 4) treatment-related morbidity compared with the combination regimen. These preliminary results suggest that comparable survival and reduced toxicity might be expected with an active single-agent as adjuvant chemotherapy in T1 or T2NOMO small cell lung cancer.
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Abstract
Foot problems are common in elderly patients, and the relief of foot pain can increase the rehabilitative potential for patients with chronic diseases, impairments, or disabilities. The authors discuss the process of evaluation of older persons, physical modalities that can be used as part of a rehabilitation program, and special considerations for various disorders common to geriatric patients. They also present a detailed description of a technique for the clinical management of peripheral arterial insufficiency.
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62
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Optimal treatment for T1-3NOMO small cell lung cancer: surgery plus adjuvant chemotherapy. Anticancer Res 1989; 9:1623-5. [PMID: 2560621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To improve treatment results in patients with surgically resectable T1-3NOMO small cell lung cancer, 16 patients were randomized to receive either neoadjuvant (preoperative) or adjuvant (postoperative) chemotherapy (cyclophosphamide, epirubicin, and etoposide). The overall survival is 45% at a median follow-up of 28.5 months. Patients treated with surgery plus adjuvant chemotherapy (n = 8) showed a significantly higher median and overall survival, proportion of 2-year survivors, and lower systemic relapse rate. These results indicate that the optimal treatment for T1-3NOMO small cell lung cancer is represented by the combination of surgery plus adjuvant chemotherapy.
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64
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65
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[A case of tuberous sclerosis: anatomo-pathologic description]. Pathologica 1989; 81:195-202. [PMID: 2771461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The authors describe the simultaneous presence of renal and pulmonary hamartomas occurring in a young man affected by tuberous sclerosis. The clinical diagnosis was based on the characteristic symptoms of epilepsy, adenoma sebaceum and mental retardation. These symptoms began at the age of four and were mostly characterized by epilepsy and adenoma sebaceum. The mental retardation was slight. The anatomopathological findings at death refer the presence of encephalic, renal and pulmonary lesions; the later are very rare.
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66
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Thyroid papillary adenocarcinoma; lipomatous-type. VIRCHOWS ARCHIV. A, PATHOLOGICAL ANATOMY AND HISTOPATHOLOGY 1989; 414:371-3. [PMID: 2496525 DOI: 10.1007/bf00734094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We present a multifocal tumour of the thyroid gland with unusual histological features, occurring in a 49-year-old woman. Two foci were characterized by the presence of a lipomatous stroma. This is only the second case of its type reported in the literature.
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67
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68
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Studies on metal carbonate complexes. 19. Complex formation in the Th(IV)H2OCO2(g) system. Inorganica Chim Acta 1987. [DOI: 10.1016/s0020-1693(00)81109-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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69
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The management of periodontal disease in patients who have received radiation therapy for head and neck cancer. SPECIAL CARE IN DENTISTRY 1987; 7:120-3. [PMID: 2954239 DOI: 10.1111/j.1754-4505.1987.tb00620.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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70
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On scheduling tasks with exponential service times and in-tree precedence constraints. ACTA INFORM 1985. [DOI: 10.1007/bf00264227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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71
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Computer-aided communication device for a child with cerebral palsy. Arch Phys Med Rehabil 1984; 65:603-5. [PMID: 6237629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
This paper describes a portable computer-aided communication device designed for a 13-year-old child with athetoid cerebral palsy. The device was intended to provide vocal output, hard-copy, correctable display, word storage capabilities, and utilize currently available technology. The design incorporated the Epson HX-20 computer, the Votrax Type 'N Talk speech synthesizer, and a customized laptray.
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72
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Therapeutic modalities and procedures. Part III: Kinetic procedures, surgical considerations, direct and alternating currents. CLINICS IN PODIATRY 1984; 1:323-41. [PMID: 6336057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Among the topics discussed in this article are kinetic procedures such as massage, manipulation, vibration, traction, and exercise; electrosurgery with high-frequency currents; and electrical stimulation.
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73
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Therapeutic modalities and procedures. Part II: Hydrotherapy and ultraviolet. CLINICS IN PODIATRY 1984; 1:315-21. [PMID: 6536395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Hydrotherapy is the external application of water for therapeutic purposes. The therapeutic devices used for producing ultraviolet radiation are the hot quartz or mercury vapor lamp, the cold quartz lamp, the sun lamp with a tungsten filament, the carbon are unit, and the black light or Wood's filter for diagnostic fluorescence.
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74
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A positive approach to rehabilitation involving the foot. CLINICS IN PODIATRY 1984; 1:249-54. [PMID: 6536389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Rehabilitation represents a total approach to patient care: the relief of pain, the restoration of the maximal level of function, and the maintenance of restored function in a pain-free state, mentally, psychologically, vocationally, and spiritually. As such, it implies a multidisciplinary approach to a complex set of problems and makes the use of a team approach imperative.
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75
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Consideration of patient evaluation and utilization. CLINICS IN PODIATRY 1984; 1:261-77. [PMID: 6536391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Once the diagnosis has been established and the treatment aims have been projected, the areas of treatment should be identified along with the desired results, frequency of treatment, and other instructions and precautions to be observed.
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76
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Some guidelines for the use of physical modalities. CLINICS IN PODIATRY 1984; 1:295-9. [PMID: 6536393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Physical therapy should be thought of in the same manner as any form of therapy, with its indications, contraindications, and side effects. The clinician should set up priorities in this form of treatment, which will be dictated by the disease or condition to be treated or by the complaints of the patient. Pain is usually a top priority, followed by swelling and biomechanical problems, including contractures.
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77
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Some considerations and guidelines for crutch walking. CLINICS IN PODIATRY 1984; 1:291-4. [PMID: 6536392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Crutch walking is a highly developed art and a physical accomplishment comparable to the most exacting of all sports. There are many advantages to early ambulation, namely, aiding circulation, preventing calcium loss in bones, and aiding the pulmonary and renal systems. It is necessary for the patient to be evaluated carefully, especially as regards selecting the proper gait and equipment to be used--that is, crutches, cane(s), parallel bars, walker, or walkette.
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78
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Therapeutic modalities and procedures. Part I: Cold and Heat. CLINICS IN PODIATRY 1984; 1:301-13. [PMID: 6536394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Therapeutic cold, or cryotherapy, has the cooling of the tissues as its primary effect. Based on the mode of application and duration of exposure, the basic physiologic effects are sedation, refrigeration, and the possibility of tissue destruction, Therapeutic heat is usually applied for two physical effects: superficial heat and deep heat. Hyperemia, sedation, and analgesia are the primary effects.
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79
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Abstract
Conditions for the preparation, purification, and maintenance of karyoplasts which could regenerate to reform whole viable cells were defined. Results of biochemical analyses of such karyoplasts at various times during regeneration indicated that a reproducible biosynthetic program was followed. Thus, an examination of the polypeptides made during regeneration by two-dimensional gel electrophoresis showed that the pattern of radiolabeled polypeptides synthesized at each time studied was specific and was significantly different from that observed at other times during regeneration. Polypeptides associated with three major cellular fractions--nuclear, cytoskeletal-microtrabecular, and soluble--were among the most dramatically regulated molecules. Other polypeptides, such as the major components of microfilaments and intermediate filaments, were synthesized at relatively constant rates and were assembled into structures throughout regeneration. Likewise, microtubules appeared to be reformed throughout regeneration, even in the absence of identifiable centriole-associated organizing centers. Finally, analysis of DNA synthesis by autoradiography showed that, even when prepared from whole cells synchronized at the G1/S interface, karyoplasts could not begin making DNA until they had regenerated an almost complete complement of cytoplasm.
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Identification of key regulated events early in the life of hybrid animal cells constructed by nuclear transplantation. Proc Natl Acad Sci U S A 1983; 80:5310-4. [PMID: 6577429 PMCID: PMC384245 DOI: 10.1073/pnas.80.17.5310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Reconstituted cells were constructed by fusion of cytoplasts from the human diploid fibroblast cell strain Detroit 532 and karyoplasts from the mouse fibroblast cell line A9. Several cellular properties were examined during the first 48 hr after nuclear transplantation. (i) The overall morphology of the cells originally resembled that of the cytoplasmic donor, Detroit 532, but rapidly changed to approximate that of the nuclear donor, A9. However, definitive changes in the microfilament structure of the reconstituted cells were not seen until 24-48 hr after fusion. These observations support the idea that the presence or absence of an ordered array of microfilament bundles is not the sole determinant of cell shape. (ii) Although cytoplasts and karyoplasts were prepared from cultures of randomly growing cells, the first division of reconstituted cells occurred in a synchronous manner. However, the initiation of DNA synthesis was not synchronized. It thus appeared that, in their first cell cycle, the cells had a G2 period of variable length. The results further suggest that the cytoplasm of interphase fibroblasts contains the material necessary to initiate or support DNA synthesis in a transplanted nucleus but not entry into mitosis. (iii) A two-dimensional gel electrophoretic analysis of polypeptide synthesis in reconstituted cell cultures showed that synthesis directed by transplanted mouse nuclei could be detected as early as 3-6 hr after fusion. Some of the mouse polypeptides detected at the earliest time points studied were not among the major polypeptides synthesized by the parental A9 cells. By about 48 hr after fusion, the pattern of polypeptides produced by reconstituted cells was almost indistinguishable from that of the nuclear donor parent cells.
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81
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Abstract
The polypeptides synthesized in cytoplasts prepared from mouse L929 cells by cytochalasin-induced enucleation were analyzed by two-dimensional gel electrophoresis. Nearly all detectable polypeptides made in parental whole cells were likewise made in cytoplasts, though in decreasing amounts, for up to at least 12 hours after enucleation. A similar analysis of cells treated with actinomycin D, an inhibitor of transcription, showed that such cells initially synthesized all of the polypeptides made by untreated cells. However, by 12 hours after treatment, the electrophoretic patterns produced by preparations of radiolabeled cells were highly aberrant, with some polypeptides apparently greatly overproduced relative to others. The results are consistent with the notion that physical removal of the nucleus disrupts the mechanisms regulating mRNA degradation in eukaryotic cells.
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82
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Globin synthesis in hybrid cells constructed by transplantation of dormant avian erythrocyte nuclei into enucleated fibroblasts. Mol Cell Biol 1981; 1:1163-76. [PMID: 7346715 PMCID: PMC369742 DOI: 10.1128/mcb.1.12.1163-1176.1981] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The polypeptides synthesized by mature embryonic erythrocytes prepared from the peripheral blood of 14- to 15-day-old chicken embryos were analyzed by two-dimensional gel electrophoresis. Fewer than 200 species of polypeptides were detected; the major polypeptides made at this time were identified as the alpha A-, alpha D-, and beta-globin chains. The dormant erythrocyte nuclei were next reactivated to transcriptional competence by transplantation into enucleated mouse or chicken embryo fibroblasts, with frequencies of cytoplast renucleation of about 50 and 90%, respectively. Since large numbers of hybrid cells could be constructed, a biochemical analysis was possible. Electrophoretic analysis of the [35S]methionine-labeled polypeptides made in the hybrid cell types showed that polypeptides having the mobilities of only two (alpha A and alpha D) of the three major adult globin chains were made as major constituents of the hybrid cells. However, analysis of 14C-amino acid-labeled polypeptides revealed that a beta-like polypeptide that lacked methionine was also synthesized in large amounts. This polypeptide was tentatively identified as the early embryonic globin species rho. Globin synthesis was detected as early as 3 h after nuclear transplantation and as late as 18 h, the last time measured in these experiments. It appeared that globin polypeptides made at very early times were translated at least partially from chicken messenger ribonucleic acid introduced into the hybrid cells during fusion, whereas those made at later times were translated primarily from newly synthesized globin messenger ribonucleic acid. The potential usefulness of this hybrid cell system in analyzing mechanisms regulating globin gene expression is discussed.
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83
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Abstract
A dramatic difference is observed in the intracellular distribution of the high mobility group (HMG) proteins when chicken embryo fibroblasts are fractionated into nucleus and cytoplasm by either mass enucleation of cytochalasin-B-treated cells or by differential centrifugation of mechanically disrupted cells. Nuclei (karyoplasts) obtained by cytochalasin B treatment of cells contain more than 90 percent of the HMG 1, while enucleated cytoplasts contain the remainder. A similar distribution between karyoplasts and cytoplasts is observed for the H1 histones and the nucleosomal core histones as anticipated. The presence of these proteins, in low amounts, in the cytoplast preparation can be accounted for by the small percentage of unenucleated cells present. In contrast, the nuclei isolated from mechanically disrupted cells contain only 30-40 percent of the total HMGs 1 and 2, the remainder being recovered in the cytosol fraction. No histone is observed in the cytosol fraction. Unike the higher molecular weight HMGs, most of the HMGs 14 and 17 sediment with the nuclei after cell lysis by mechanical disruption. The distribution of HMGs is unaffected by incubating cells with cytochalasin B and mechanically fractionating rather than enucleating them. Therefore, the dramatic difference in HMG 1 distribution observed using the two fractionation techniques cannot be explained by a cytochalasin-B-induced redistribution. On reextraction and sedimentation of isolated nuclei obtained by mechanical cell disruption, only 8 percent of the HMG 1 is released to the supernate. Thus, the majority of the HMG 1 originally isolated with these nuclei, representing 35 percent of the total HMG 1, is stably bound, as is all the HMGs 14 and 17. The remaining 65 percent of the HMGs 1 and 2 is unstably bound and leaks to the cytosol fraction under the conditions of mechanical disruption. It is suggested that the unstably bound HMGs form a protein pool capable of equilibrating between cytoplasm and stably bound HMGs.
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84
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Biochemical evidence for distinct receptors which mediate the effect of PGI2 and PGD2 on human platelets. Prog Lipid Res 1981. [DOI: 10.1016/0163-7827(81)90111-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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85
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Abstract
Evaluation of ten children with Pseudomonas bone and joint infections resulting from puncture wounds of the foot identified a definite pattern to sequelae. The longer the symptoms were present before adequate treatment was instituted the greater was the risk of bone and joint destruction along with the development of chronic osteomyelitis. The syndrome usually does not produce systemic signs, but the patterns is characteristic and should be considered after any puncture wound of the foot in which the symptoms worsen instead of improving with time.
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Alternate pathway activation of complement in a Proteus mirabilis ulceration of the cornea. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1978; 96:1659-61. [PMID: 356830 DOI: 10.1001/archopht.1978.03910060285021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A 63-year-old patient had an extensive infiltration, ulceration, and eventual perforation of the cornea caused by Proteus mirabilis. Histopathological examination of corneal tissue that was obtained at keratoplasty disclosed that the stroma was ulcerated with a diffuse infiltration of polymorphonuclear leukocytes. Immunopathological examination of the cornea revealed prominent and diffuse staining for properdin and C3 complement. There was an absence of staining for IgG, IgA, IgM, IgE, and C4 complement. These findings suggest that the alternate pathway of complement was activated in this ulcerated cornea and that immunopathological phenomena contribute to the polymorphonuclear infiltration found with Gram-negative ulcerations of the human cornea.
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87
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Ultrasound and some podiatric considerations. JOURNAL OF THE AMERICAN PODIATRY ASSOCIATION 1976; 66:682-6. [PMID: 965691 DOI: 10.7547/87507315-66-9-682] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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88
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89
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91
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PRINCIPAL PARTITION AND PRINCIPAL MINORS OF A MATROID, WITH APPLICATIONS. Ann N Y Acad Sci 1970. [DOI: 10.1111/j.1749-6632.1970.tb45115.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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92
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A positive approach to rehabilitation. JOURNAL OF THE AMERICAN PODIATRY ASSOCIATION 1970; 60:239-43. [PMID: 4245758 DOI: 10.7547/87507315-60-6-239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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93
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95
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[Intraosseous stabilization. Report of 17-years application. 2]. LA TRIBUNA ODONTOLOGICA 1969; 53:82-7 passim. [PMID: 5258686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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96
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[Intraosseous stabilization. Result of 17 years of its application]. LA TRIBUNA ODONTOLOGICA 1969; 53:39-48. [PMID: 5255049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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97
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Gross muscle evaluation by the podiatrist. JOURNAL OF THE AMERICAN PODIATRY ASSOCIATION 1967; 57:309-15. [PMID: 6046562 DOI: 10.7547/87507315-57-7-309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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