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91.
The past decade has been marked by significant advances in the application of gene transfer into living cells of animals and humans, with the resulting catapulting of preclinical and basic scientific concepts into therapeutic trials. A variety of virus-mediated gene delivery techniques have proved to be superior to other methodologies. This article concisely reviews the current status of gene and tumor therapy, focusing on virus-based technologies, describes the molecular biology of neurotropic herpesviruses and the application of herpes simplex virus, a relative of pseudorabies virus (PRV) in gene transfer and cancer therapy protocols. Finally, it addresses the issue of whether PRV, a nonhuman pathogen, could serve as a suitable research and therapeutic tool as concerns genetic and tumor therapy. 相似文献
92.
New types of hydrophilic gels based on N-(2-hydroxypropyl)methacrylamide which contain oligopeptide sequences in the crosslinks were prepared. These gels are enzymatically degradable by chymotrypsin. The rate of their degradation may be varied within a broad range by changes in the length and detailestructure of the oligopeptide sequence in the crosslinks and by changing their network density. 相似文献
93.
94.
Janać B Pesić V Peković S Rakić L Stojiljković M 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,165(3):402-406
The time-course of changes of basal and amphetamine (AMPH)-induced locomotor and stereotypic activities in adult male Wistar rats after a single ribavirin injection was studied. In the first set of experiments, 10, 20 or 30 mg ribavirin/kg body weight (b.w.) were injected i.p. to rats and their basal motor activities were recorded every 10 min for 2 h and compared with those of saline-treated controls. In the second set of experiments, the animals were pretreated with ribavirin and 20 min later i.p. injected with AMPH (1.5 mg/kg b.w.). The controls received AMPH 20 min after the saline injection. Motor activity was recorded after the first injection and until 120 min after AMPH administration. Ribavirin did not significantly affect the time-course of either basal locomotor or stereotypic activities. Pretreatment with any of the applied ribavirin doses decreased the AMPH-induced hyperlocomotor response. However, the most pronounced effect was observed with ribavirin doses of 20 mg/kg and 30 mg/kg when administered during the first 10 min and 30 min after the AMPH injection respectively. In contrast, the stereotypic activities of these animals were only slightly changed. These results indicate a different susceptibility of regions in the basal ganglia to ribavirin. 相似文献
95.
A subcutaneous polymeric drug delivery system, which consists of a polymeric matrix of poly(hydroxyethyl methacrylate-bisglycol acrylate), was developed. 5-fluorouracil was used as the model anticancer drug. Polymer-drug beads with a diameter of 3 mm were prepared by low-temperature radiation polymerization. In order to modify the release rate, polymeric beads with different composition, drug loading and crosslinking density were obtained. The kinetics of drug release were described by the expression Mt/M infinity = ktn. The diffusional release exponent 'n', which was calculated from the release curves, indicated that the mechanism of drug release from the polymeric matrix is due to the anomalous (non-Fickian) type of diffusion. 相似文献
96.
Antibody content against rabbit red blood cells (anti-RaRBC) in murine sera of different strains (Swiss, CBA, C57BL/6, AKR, BALB/c) and activity of complement alternative pathway (AP) were investigated. In contrast to the CBA and C57BL/6, random-bred Swiss strain and inbred BALB/c and AKR strains are good producers of these natural antibodies. There is no correlation between AP activity and anti-RaRBC content. Isolated human anti-RaRBC antibodies, IgM and IgG classes, lead to the enhancement of APhu and APmo activity, contrary to the murine anti-RaRBC which belong solely to IgM class, and do not express this capability. 相似文献
97.
Bernard R Labelle V Negre P Tardieu S Azulay JP Malzac P Mattéi JF Leguern E Philip N Lévy N 《European journal of human genetics : EJHG》2000,8(3):229-235
Charcot-Marie-Tooth disease, type 1A (CMT1A) is caused in most cases by a 1.5 Mb duplication on chromosome 17p11.2 arising after unequal crossing-over between repeated sequences called CMT1A-REPs, flanking the 1.5 Mb unit. A 3.2 kb recombination hot spot has been defined, resulting in a junction fragment between EcoRI (distal CMT1A-REP) and SacI (proximal CMT1A-REP). This was further reduced to a 1.7kb EcoRI-NsiI fragment, and recently to a 731 bp hot spot region within this fragment. We describe the CMT1A-REPs-based PCR method used to identify CMT1A duplications and report on a family case in which a 29-year-old pregnant woman requested prenatal diagnosis for two successive pregnancies because her husband was affected with CMT1A. Our method enabled us to characterise the duplication in both foetuses and demonstrate that it arose from a rare recombination event taking place outside the 1.7 kb region. Since our approach is simple and enables the entire set of duplications occurring after recombination in the enlarged 3.2kb region including the hot spot to be detected, we suggest it might be considered for use in primary screening for pre- and postnatal diagnosis of CMT1A. 相似文献
98.
D. Quiñones-Pérez P. Goñi M. C. Rubio F. Baquero R. Gómez–Lus R. Del Campo 《Clinical microbiology and infection》2006,12(8):793-797
This study describes the genetic relationships and antimicrobial resistance determinants found among 99 clinical isolates of enterococci from 15 different hospitals in Cuba. Pulsed-field gel electrophoresis SmaI analysis demonstrated a high degree of genetic diversity. A limited number of multiresistant Enterococcus faecalis clones, showing resistance to three or more families of antimicrobial agents, were detected simultaneously in different institutions, suggesting inter-hospital circulation of selected clones, and/or selection of particular clones following their introduction into the hospital environment. Antimicrobial resistance determinants, including erm(B), aac(6')-aph(2'), aph(3'), ant(6), vanB (E. faecalis) and vanA (Enterococcus faecium) were detected by PCR in various isolates. 相似文献
99.
B. Şahin S. Paydaş E. Coşar K. Biçakçi B. Hazar 《European journal of clinical microbiology & infectious diseases》1996,15(11):866-869
Several problems in the management of life-threatening mucormycosis remain unresolved, necessitating new methods of management. Four patients with histopathologically proven rhinocerebral mucormycosis were treated with high cumulative doses of granulocyte colony-stimulating factor (G-CSF). All had multiple predisposing factors for mucormycosis, particularly leukemia and neutropenia. Two patients refractory to fluconazole therapy were treated with liposomal amphotericin B. The improvement in clinical manifestations was closely related to neutrophil recovery, and all patients were alive at the end of therapy. In addition to surgical debridement and antifungal therapy, G-CSF seems to have played a role in their survival. 相似文献
100.
Hník P. Holas M. Krekule I. Kříž N. Mejsnar J. Smieško V. Ujec E. Vyskočil F. 《Pflügers Archiv : European journal of physiology》1976,362(1):85-94
Using liquid ion-exchanger semimicroelectrodes with a side pore, we measured changes of extracellular potassium concentration (Ke
+) in adult rabbit and cat gastrocnemius muscles and in venous effluent blood flowing from the cat gastrocnemius muscle during various bouts of activity induced by sciatic nerve stimulation.
相似文献
1. | Isometric tetanic contractions (at 50 Hz) of various durations caused transient accumulation of Ke + which was non-linearly related to the duration of muscle activity. The peak values of Ke + in response to muscle stimulation were analogous in rabbits and cats, attaining values, e.g. after a 20-s isometric tetanus, between 8–9 mEq/lK+ in both species. |
2. | Potassium concentration in venous effluent blood (K ven + ) was transiently increased after isometric tetani. Since blood flow was measured at the same time, it was possible to calculate the amount of K+ lost by the muscle after tetani of various durations. A 32 g gastrocnemius muscle of the cat, for example, loses 9.36±1.52 EqK+ after a 20-s isometric tetanus, which corresponds roughly to 0.5% of the total muscle potassium content. The loss of K+ in this muscle was 29.3 pEq K+/impulse/100 g fresh muscle tissue. |
3. | There was no evident difference between the amount of K+ released during isometric tetani, or tetanic contractions performed under isotonic conditions. Single twitches evoked by indirect stimulation at 1 Hz for several minutes also induced a small rise in K ven + . |
4. | If the loss of K+ from the muscle into the blood stream is transiently prevented by arterio-venous occlusion installed immediately before a 10-s isometric tetanus, most K+ is released subsequently when blood flow is renewed, if the occlusion lasts for 20–25 s. It is not until blood flow is occluded for 40–60 s that most K+ is apparently resorbed and only a minor portion is released and is to be found in the venous blood. |
5. | The transient accumulation of muscle extracellular potassium may locally affect nerve endings, skeletal and smooth muscle cells. |