Time-related effects of general functional training in spinal cord-injured rats

OBJECTIVES:

This prospective, randomized, experimental study with rats aimed to investigate the influence of general treatment strategies on the motor recovery of Wistar rats with moderate contusive spinal cord injury.

METHODS:

A total of 51 Wistar rats were randomized into five groups: control, maze, ramp, runway, and sham (laminectomy only). The rats underwent spinal cord injury at the T9-T10 levels using the NYU-Impactor. Each group was trained for 12 minutes twice a week for two weeks before and five weeks after the spinal cord injury, except for the control group. Functional motor recovery was assessed with the Basso, Beattie, and Bresnahan Scale on the first postoperative day and then once a week for five weeks. The animals were euthanized, and the spinal cords were collected for histological analysis.

RESULTS:

Ramp and maze groups showed an earlier and greater functional improvement effect than the control and runway groups. However, over time, unexpectedly, all of the groups showed similar effects as the control group, with spontaneous recovery. There were no histological differences in the injured area between the trained and control groups.

CONCLUSION:

Short-term benefits can be associated with a specific training regime; however, the same training was ineffective at maintaining superior long-term recovery. These results might support new considerations before hospital discharge of patients with spinal cord injuries.     

Mixed leukocyte reaction in rats. Effect of immunization with bovine encephalitogenic protein and Freund's complete adjuvant.

Rats of certain strains immunized with bovine encephalitogenic protein (EP) in Freund's complete adjuvant develop an impairment of the mixed leukocyte reaction (MLR) similar to that seen in rabbits with experimental autoimmune encephalomyelitis and in humans with certain diseases, including multiple sclerosis. The rats mount a cell-bound response to EP, but encephalomyelitis does not develop. The component causing the impairment was analysed in a culture system using inbred rat strains and F1 hybrids, thoracic duct cells as a source of lymphocytes, and blood as a supplement to the cultures. In normal rats, it was shown that the effects of responding and of stimulating lymphocytes could be separated and that the supportive action of the added blood was probably due to macrophages (monocytes); also that the added blood could in many experiments be replaced with 2-mercaptoethanol (2-ME). The impairment present in immunized rats is at least largely due to a defective supportive activity of the blood (monocytes) and can be restored with 2-ME. The results argue that the MLR impairment seen in immunized rats is due to a faulty macrophage function.     

The prophylactic and therapeutic effects of gold sodium thiomalate against adjuvant-induced polyarthritis in rats

Parenteral gold, which has been shown to be an effective therapeutic agent in rheumatoid arthritis, was found to significantly suppress development of both the primary and secondary lesions of adjuvant-induced polyarthritis in the rat. This prophylactic effect as well as serum gold levels were dose-related. However, the therapeutic effect of gold sodium thiomalate (GST) was much less pronounced when administered to rats with established disease. The progression of both primary and secondary lesions associated with adjuvant arthritis was retarded during the first week of treatment only with the highest doses of GST (10.0 and 20.0 mg/kg). During the ensuing two weeks of daily drug administration however, the disease in these rats progressed at a rate similar to the arthritic control animals. X-rays taken of at least two animals from each group at the end of these experiments revealed anatomical findings that closely paralleled observations of hind paw volumes. In addition, the remaining animals in each group were sacrificed by decapitation and the following physiologic and biochemical parameters measured: body weight gain, erythrocyte sedimentation rate, serum albumin/globulin ratios and plasma activities of lactic dehydrogenase, -glucuronidase, acid phosphatase and lysozyme. All of these parameters were significantly altered in the arthritic control animals. However, neither prophylactic nor therapeutic treatment with GST reversed any of these manifestations of the disease. The results will be discussed in relation to our findings with clinically effective steroidal (hydrocortisone) and nonsteroidal (aspirin and indomethacin) antiarthritic agents on adjuvant-induced polyarthritis in rats.     

The use of lipid-coated nanodiamond to improve bioavailability and efficacy of sorafenib in resisting metastasis of gastric cancer

The metastasis is one of the greatest challenges for successful cancer therapy. Herein, we report a lipid-coated nanodiamond (ND) system loading water-insoluble sorafenib (SND) to improve the bioavailability and efficacy on suppression of cancer metastasis. SND was homogenous nanoassemblies with the mean diameter of 127.6 ± 12.9 nm. Compared with the drug suspension, the sorafenib concentration in gastrointestinal (GI) tract and major organs was significantly increased by SND. Moreover, the oral bioavailability of sorafenib was greatly improved 7.64-fold by SND. However, the ND in SND could not be absorbed into the mucus of GI tract or distributed into major organs after oral administration. Furthermore, the sorafenib concentration in tumor tissue was markedly improved 14.95 folds by SND, and SND demonstrated an efficient and impressive tumor growth inhibition effect in tumor xenograft models. In particular, the metastasis of gastric cancer to distant organs of liver and kidney was remarkably suppressed by SND, which was verified by the detection of macroscopic metastatic nodules, histological examination and immunofluorescence measurements. Thereby, the lipid-coated ND could be a promising drug delivery platform for improving the oral bioavailability of lipophilic drugs and treatment of cancer metastasis.     

Physiological response in rats to protein conjugates of angiotensin II during long-term immunization

P. K. Anokhin Research Institute of Normal Physiology, Academy of Medical Sciences of the USSR. Institute of Biological and Medical Chemistry, Academy of Medical Sciences the USSR, Moscow. (Presented by Academician of the Academy Medical Sciences K. V. Sudakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 12, pp. 563–565, December, 1990.     

Alteration in host cell tropism limits the efficacy of immunization with a surface protein of malaria merozoites

Immunization with Plasmodium yoelii merozoite surface protein-8 (PyMSP-8) has been shown to protect mice against lethal P. yoelii 17XL malaria. Here we demonstrate that PyMSP-8-specific antibodies preferentially suppress P. yoelii 17XL growth in mature erythrocytes compared to growth in reticulocytes and do not suppress the growth of nonlethal P. yoelii 17X, a parasite that primarily replicates in reticulocytes. The protection against normocyte-associated P. yoelii malaria parasites is mediated by antibodies that recognize conformational epitopes of PyMSP-8 that are nonpolymorphic. We examined changes in gene expression in reticulocyte-restricted P. yoelii 17XL parasites that escaped neutralization by PyMSP-8-specific antibodies using P. yoelii DNA microarrays. Of interest, Pymsp-8 gene expression decreased, while the expression of msp-1, msp-7, and several rhoptry protein genes increased. Breakthrough parasites also exhibited increases in the expression of a subset of yir and Pyst-a genes that are predicted to encode polymorphic antigens expressed on the surface of infected erythrocytes. These data suggest that changes in the expression of parasite proteins expressed on the merozoite surface, as well as the surface of infected erythrocytes, may alter host cell tropism and contribute to the ability of malaria parasites to evade merozoite-specific, neutralizing antibodies.     

Alterations in serum proteins of rats after immunization with Freund's adjuvant andBordetella pertussis vaccine

Immunization is known to modify the level of certain circulating serum proteins. In this study we describe changes in the electrophoretic pattern of serum proteins after immunization with two different antigens: RaTE and BSA incorporated with three different adjuvants: complete Freund's adjuvant, incomplete Freund's adjuvant, andBordetella pertussis vaccine. Serum albumin and globulins were decreased while ₁, ₂, and globulins had a tendency to increase. The serum protein modifications were observed as early as 24 h after immunization and were not reversed by histamine or serotonin antagonists. Some physiopathological hypotheses of their possible effects in immunization are discussed.This study was supported by PHS Research Grant CA 02357 from the National Cancer Institute. It is publication no 75 from the Center for Immunology.     

佐剂关节炎大鼠脊神经节中核因子kappa B表达的研究

目的：研究核因子kappa B(NF-κB)在佐剂关节炎（AA）大鼠脊神经节（L1-L4）中的表达,以探讨类风湿关节炎（RA）发病的神经-内分泌—免疫学机制。 方法： 用免疫组织化学法检测脊神经节中NF-κB蛋白表达，用Western blotting法分析脊神经节细胞胞核蛋白中NF-κB含量改变。 结果： 在AA大鼠L1-L4脊神经节细胞中，NF-κB蛋白表达明显高于正常对照组（P<001）,且活化的NF-κB（胞核蛋白中NF-κB）含量明显高于正常对照组（P<001）。细胞核内P65蛋白表达量与关节肿胀程度呈正相关。结论： 脊神经节中NF-κB活化可能参与RA发病机制。     

The serological response of the chicken to a protein antigen in multiple emulsion oil adjuvant

In adult chickens administration of 4 mg of bovine serum albumin as a multiple emulsion (water-in-oil-in-water) by the s.c., i.m. or i.p. route stimulated a persistent precipitin response that was still detectable in nine out of twelve birds when the experiment was terminated 286 days after injection. In each group the mean serum total antibody response curve was biphasic. An initial rapid response, reaching a peak of 350–500 μg antibody N/ml of serum on day 7–9, declined in fluctuating fashion and was succeeded after 30–60 days by a slower sustained rise in antibody level, reaching a peak similar to that of the initial response.

Splenectomy impaired precipitin production, delayed and suppressed the initial phase of antibody synthesis, but did not significantly alter the second phase. Synthesis during the secondary phase is considered to proceed in the granulomata where, in contrast to other tissues of the body, antigen remains in readily detectable amounts for several weeks after injection.

     

Long-term efficacy of a checklist to improve patient education in cardiology

In a randomised controlled trial a Frequently Asked Questions (FAQ) checklist intended to prepare coronary artery disease (CAD) outpatients for a medical check-up visit at the cardiologist was evaluated. The checklist was mailed to patients in preparation to their visits after 1, 4 and 10 months following patients' discharge from hospitalisation for CAD. It was hypothesised that the intervention would result in lower state anxiety, better patient-doctor communication, more knowledge of CAD and greater patient satisfaction, while it would not result in longer visits. Repeated measurements analyses of covariance showed that experimental patients (N = 46) were less anxious before the first visit. This visit was shorter than in the controls, though the third visit was longer. Control patients (N = 59) showed more CAD knowledge than experimental patients at the first and third visit. Experimental patients found the checklist useful, though its value diminished at subsequent visits. Using the checklist thus decreased anxiety prior to the first visit and the duration of that visit, while negatively affecting knowledge. No conclusions about long-term effects could be drawn, due to the likelihood of type II and type III errors. Process evaluation indicated that the approach used is not sufficiently stimulating for patients to use as a preparation to every visit.     

In vitro and in vivo evaluation of the efficacy of nanoformulation of siRNA as an adjuvant to improve the anticancer potential of cisplatin

With the advent of advanced tools in molecular biology, understanding on cancer etiology has improved. siRNA can be considered as an effective tool in cancer therapy through silencing overexpressed genes responsible for cell proliferation or preventing apoptosis. However, some contentious issues such as stability and delivery of siRNA are to be resolved. Bcl-2, an anti-apoptotic gene, is overexpressed in a wide variety of cancers and responsible for drug resistance tumors. In our earlier studies, we developed a nanoformulation of siRNA targeting the Bcl-2 and achieved successful delivery in vitro and in vivo. To extend the scope of the study further, in the present work, we studied the role of nanoformulation of siRNA as adjuvant in chemotherapy with cisplatin. Dose dependant nephrotoxicity is a serious concern apart from other adverse effects of cisplatin. The IC₅₀ value for cisplatin was decreased from 9.83 μmol/l to 7.43 μmol/l in HeLa cells and from 8.54 μmol/l to 6.68 μmol/l in HEp-2 cells, when it was given with siRNA nanoformulation. Cisplatin at the dose of 1.7 mg/kg in combination with siRNA nanoformulation was effective in improving the lifespan of tumor bearing mice with significant decrease in nephrotoxicity.     

The use of gold nanoparticles to enhance radiotherapy in mice

Mice bearing subcutaneous EMT-6 mammary carcinomas received a single intravenous injection of 1.9 nm diameter gold particles (up to 2.7 g Au/kg body weight), which elevated concentrations of gold to 7 mg Au/g in tumours. Tumour-to-normal-tissue gold concentration ratios remained approximately 8:1 during several minutes of 250 kVp x-ray therapy. One-year survival was 86% versus 20% with x-rays alone and 0% with gold alone. The increase in tumours safely ablated was dependent on the amount of gold injected. The gold nanoparticles were apparently non-toxic to mice and were largely cleared from the body through the kidneys. This novel use of small gold nanoparticles permitted achievement of the high metal content in tumours necessary for significant high-Z radioenhancement.     

The use of a priori information in the detection of mammographic microcalcifications to improve their classification

In this work, we present a calcification-detection scheme that automatically localizes calcifications in a previously detected cluster in order to generate the input for a cluster-classification scheme developed in the past. The calcification-detection scheme makes use of three pieces of a priori information: the location of the center of the cluster, the size of the cluster, and the approximate number of calcifications in the cluster. This information can be obtained either automatically from a cluster-detection scheme or manually by a radiologist. It is used to analyze only the portion of the mammogram that contains a cluster and to identify the individual calcifications more accurately, after enhancing them by means of a "Difference of Gaussians" filter. Classification performances (patient-based Az=0.92; cluster-based Az=0.72) comparable to those obtained by using manually-identified calcifications (patient-based Az=0.92; cluster-based Az=0.82) can be achieved.     

The use of state-dependent modulation of spinal reflexes as a tool to investigate the organization of spinal interneurons

This review examines the proposition that state-dependent modulation of transmission through spinal reflex pathways can be used as an investigative tool to reveal details about the organization of spinal interneurons into functional circuits. The first set of examples includes the use of spinal and supraspinal lesions, as well as the administration of the drug l-dihydroxyphenylalanine (l-DOPA), to produce different, relatively stable ”states” of the central nervous system (CNS), revealing previously unsuspected spinal pathways activated by the flexor reflex afferents (FRA). The second set of examples deals with the use of fictive locomotion and scratching to investigate the organization of oligosynaptic excitatory and inhibitory reflex pathways from cutaneous and muscle afferents. As in the first set of examples, several hitherto unknown reflex pathways have been found only during the flexion or extension phases of rhythmic locomotion, which are regarded as different CNS states. Differences in the patterns of control can be used to infer the existence of distinct sets of reflex pathway interneurons that have remarkably precise input/output relations. Received: 4 February 1999 / Accepted: 19 April 1999     

The effect of electrical stimulation on leg muscle pump activity in spinal cord-injured and able-bodied individuals

The purpose of this study was to examine the difference in: (1) effective muscle pump activity (MPA) between voluntary and electrically (ES) induced contractions in able-bodied subjects (ABS); and (2) ES-induced MPA between spinal cord-injured (SCI) individuals and ABS. MPA was measured as relative volume changes in the calf using strain-gauge plethysmography during repeated muscle contractions in the supine position while venous outflow was impeded by a thigh cuff inflated to a range of pressures. Ten SCI individuals and ten ABS participated in this study. ABS showed no significant difference between voluntary and electrically induced MPA [58.1 (18.4)% versus 67.7 (8.7)%, respectively]. SCI individuals showed a significantly lower ES-induced MPA than ABS [21.5 (15.9)% versus 67.7 (8.7)%, respectively]. The low MPA in SCI individuals may be explained by: (1) extensive leg muscle atrophy and/or (2) an “atrophic” vascular system in the legs. The electrical current level seemed to influence MPA (43 mA, 21.5% versus 60 mA, 30.8%) for SCI individuals, whereas no influence of muscle contraction rate on MPA was observed in ABS. The results of this study demonstrate that although ES-induced leg muscle contractions result in adequate MPA in ABS, it leads to significantly less effective MPA in SCI individuals. Accepted: 21 March 2000     

The therapeutic efficacy of hemodialysis in schizophrenia

Prompted by previous reports of substantial clinical improvement in most schizophrenic patients given hemodialysis for their psychiatric condition, we studied the efficacy of hemodialysis in 15 schizophrenic outpatients, under double-blind, controlled conditions. The patients were randomly assigned to either a real-sham or sham-real sequence of dialysis treatment. Results of repeated measurement and other analyses of data on symptoms and behavior that were collected before study treatment, at crossover, and at the end of treatment revealed no difference between the effects of real and sham dialysis. These results provide important experimental evidence of the lack of therapeutic efficacy of hemodialysis in schizophrenia.     

The use of PVP as a polymeric carrier to improve the plasma half-life of drugs

To achieve an optimum drug delivery such as targeting or controlled release utilizing bioconjugation with polymeric modifier, the conjugate between drugs and polymeric modifiers must be designed to show desirable pharmacokinetic characteristics in vivo. In this study, we assessed the biopharmaceutical properties of various nonionic water-soluble polymers as polymeric drug carriers. Polyvinylpyrrolidone (PVP) showed the longest mean resident time (MRT) after i.v. injection of all nonionic polymers with the same molecular size. In fact, tumor necrosis factor-alpha (TNF-alpha) bioconjugated with PVP (PVP-TNF-alpha) circulated longer than TNF-alpha bioconjugated with polyethylene glycol (PEG-TNF-alpha) with the same molecular size. Each nonionic polymeric modifier showed a different tissue distribution. Dextran was accumulated in the spleen and liver. Polydimethylacrylamide (PDAAm) tended to distribute in the kidney. However, PVP showed the minimum volume of tissue distribution. These results suggested that PVP is the most suitable polymeric modifier for prolonging the circulation lifetime of a drug and localizing the conjugated drug in blood.     

Passive immunization with bovine milk containing antibodies to a cell surface protein antigen-glucosyltransferase fusion protein protects rats against dental caries

Cell surface protein antigen (PAc) and glucosyltransferases (GTF) of Streptococcus mutans are major colonization factors of the organism. We prepared bovine milk containing antibodies against a fusion of the saliva-binding alanine-rich region of PAc with the glucan-binding domain of GTF-I. This study examined the effect of the immune milk on the cariogenicity of S. mutans in a rat model. Concentrated immune milk was fed to rats once a day for 55 days. The group that received immune milk had significantly less caries development than controls.     

Prevention of adjuvant arthritis in rats by a nonapeptide from the 65-kD mycobacterial heat-shock protein.

Adjuvant arthritis in Lewis rats is a model of T cell-mediated autoimmune arthritis resembling human rheumatoid arthritis. A nonapeptide from the 65-kD heat-shock protein of Mycobacterium bovis BCG, amino acid sequence 180-188, has been described to carry the dominant immunogenic epitope(s) for both arthritis-protective and arthritogenic T cell clones. Here we demonstrate that immunizations with the synthetic nonapeptide completely protected rats against adjuvant arthritis induced by M. tuberculosis. Interestingly, deletion of the N-terminal threonine of the nonapeptide resulted in loss of the protective activity. Pretreatments with the nonapeptide resulted in an immune response to the nonapeptide and to M. tuberculosis. After immunizations with the synthetic nonapeptide, only low titres of nonapeptide-specific antibodies were produced, whereas a significant cellular immune response to the nonapeptide was observed. In addition, the protection was transferable to naive rats by spleen T cells. These findings document the requirement of a T cell-specific immune response to the dominant epitope of the 65-kD mycobacterial heat-shock protein for the protection against adjuvant arthritis and suggest the feasibility of immune intervention in autoimmune arthritis through the use of synthetic peptides.