A simple technique for rapid implantation of a permanent cannula into the rat brain ventricular system.

A simple, rapid method of implantation of a permanent cannula into the ventricular system of the rat brain was developed using polyethylene tubing. Intraventricular injections were performed on nonrestrained, conscious animals. This cannula was used repeatedly during several weeks.     

Plasmapheresis in the initial treatment of insulin-dependent diabetes mellitus in children.

Several factors indicate that autoimmune mechanisms may play a part in the aetiology of insulin-dependent diabetes mellitus. At the onset of the disease in 10 children (aged 11-16 years) plasmapheresis was performed four times over one to two weeks. Seventeen age-matched children with the same clinical features served as controls. The C-peptide concentrations at onset were the same in the two groups, but after one month the children treated with plasmapheresis had significantly higher values. This difference became even more pronounced after three, nine, and 18 months, both during fasting and at the maximum response to a standardised meal. The study group also had a significantly more stable metabolism, longer partial remission, and no higher insulin requirement. Of the 10 treated children islet-cell cytoplasmic antibodies were present in seven before plasmapheresis and in nine during treatment. The antibodies remained detectable in five and six out of nine patients at one and six months respectively after plasmapheresis. Although the mechanisms are obscure, plasmapheresis performed at the onset of insulin-dependent diabetes mellitus may help to preserve beta-cell function.     

Percutaneous liver core biopsy in rats: an alternative to minilaparotomy

Sampling of rat hepatic tissue for histomorphological analysis is usually performed in two different ways: either by killing the animals or by minilaparotomy.In this study we describe a percutaneous core biopsy technique which has been used on day 7, 14 and 21 after allogeneic rat liver transplantation (DA → LEW) in order to examine grafts for rejection in different treatment groups. Fifty-two liver biopsies were performed in 24 animals using a 16-gauge intravenous cannula. Forty-five provided usable specimens which were sufficient for both light or electron microscopy and immunohistochemical analyses to determine the degree of graft rejection. In 7 cases (13.5%) sampling was unsuccessful, especially on day 21 after transplantation, as the plastic cannula could not penetrate the hardened tissue. In 3 animals (5.8%) puncture was immediately followed by death due to perforation of the diaphragm or ether intoxication.In conclusion, this technique is a reliable method for providing ample tissue samples from the rat liver with a low risk of complications.     

Hemodynamic effects of 15-microm-diameter microspheres on the rat pulmonary circulation.

The microsphere method has been used extensively to measure regional blood flow in large laboratory animals. A fundamental premise of the method is that microspheres do not alter regional flow or vascular tone. Whereas this assumption is accepted in large animals, it may not be valid in the pulmonary circulation of smaller animals. Three studies were performed to determine the hemodynamic effects of microspheres on the rat pulmonary circulation. Increasing numbers of 15-microm-diameter microspheres were injected into a fully dilated, isolated-lung preparation. Vascular resistance increased 0.8% for every 100,000 microspheres injected. Microspheres were also injected into an isolated-lung preparation in which vascular tone was increased with hypoxia. Microspheres did not induce vasodilatation, as reported in other vascular beds. Fluorescent microspheres were injected via tail veins into awake rats, and the spatial locations of the microspheres were determined. Regional distributions remained highly correlated when microspheres of one color were injected after microspheres of another color. This indicates that the initial injection did not alter regional perfusion. We conclude that, when used in appropriate numbers, 15-microm-diameter microspheres do not alter regional flow or vascular tone in the rat pulmonary circulation.     

Plasma exchange therapy for severe Graves' ophthalmopathy

The authors report on the treatment of 11 Graves' disease patients with severe ophthalmopathy by the use of intensive plasma exchange followed by immunosuppression. Results were evaluated by comparing the ophthalmopathy index and the orbital CT scan performed before and after plasmapheresis. Favorable results were obtained in 91% of the patients. The best positive effects of plasmapheresis were observed for soft tissue involvement, proptosis, tonometry, and visual acuity. Furthermore, a significant reduction in the size and density of enlarged extraocular muscles was also found. Six months after withdrawal of immunosuppression, 4 patients presented a moderate recurrence of ophthalmopathy and were treated successfully by a second course of plasmapheresis, followed by short immunosuppression. In conclusion, the use of intensive plasma exchange associated with immunosuppression is an effective approach to the treatment of severe Graves' ophthalmopathy. It yields rapid and dramatic improvements that are maintained in most patients after withdrawal of immunosuppression. Recurrences are still responsive to the beneficial effects of this combined treatment.     

Plasmapheresis in the treatment of hepatic coma]

Fourteen patients, including 6 with viral hepatitis B and 8 with liver cirrhosis were treated with plasmapheresis for hepatic coma. Altogether 29 plasmaphereses were carried out. Complete recovery was achieved in one patient with viral hepatitis B and in 3 patients with liver cirrhosis. Plasmapheresis should be performed in patients with severe lesions to the liver. Classification of patients to the treatment should include clinical examination, biochemical and enzymatic tests, and evaluation of liver reserve with isotope hepatography. In case of the acute poisoning with hepatotoxic agents indications to plasmapheresis should be evaluated from the toxicologic point of view.     

A novel bile duct cannulation method with tail cuff exteriorization allowing continuous intravenous infusion and enterohepatic recirculation in the unrestrained rat.

A variety of bile duct cannulation methods have been used in the study of biliary excretion in the rat. We now report the validation and use of one such method. In this method, the common bile duct and duodenum were cannulated, the free ends of the cannulae tunnelled through the abdominal wall, passed through a trochar and exteriorized at the ventral aspect of the tail. A purpose-designed stainless steel tail cuff was then attached, to protect the cannulae from the rat. The cannulae were passed through the top of a metabolism cage and attached to a dual swivel that allows the rat freedom of movement within the metabolism cage. Where necessary an additional cannula could be placed in the femoral vein to allow infusion of test material or blood sampling. The results demonstrate that the method is robust and that its use allows a reliable correlation between surgically prepared and intact animals, as physiological parameters are allowed to return to normal prior to inclusion of the animals in the study. The technique allows the animals a great deal of freedom and, as such, is considered to minimize stress associated with the procedure. This fact is reflected in the reliability and reproducibility of the data obtained over the wide range of studies that have been conducted using this method. This method has been in use for over 4 years at Inveresk and this paper describes the authors' experience with the method to date.     

Bromodeoxyuridine Immunohistochemistry for Evaluating Age-Related Changes in the Rat Mandibular Condyle Decalcified by Intravenous Infusion

Age-related changes in cell proliferation kinetics of the mandibular condyle were studied in Sprague-Dawley rats using bromodeoxyuridine (BrdUrd) immunohistochemistry in decalcified, paraffin-embedded tissues. Intraperitoneal injection of 40 mg/kg BrdUrd was given 1 hr before animal sacrifice. Continuous perfusion of EDTA solution via the left ventricle shortened the decalcification time. Immunohistochemical staining was performed with monoclonal anti-BrdUrd antibody. BrdUrd labeled cells, i.e., the S-phase cells, were clearly visible with well-preserved cytological detail. Their nuclei exhibited homogeneously stained granules. The labeling index in the intermediate zone of the condyle decreased with increasing age of the animals. This method is useful for evaluating physiological and pathological changes of the rat mandibular condyle as well as other bones and joints.     

Determination of epimedin C in rat plasma by reversed-phase high-performance chromatography after oral administration of Herba Epimedii extract

A simple high-performance liquid chromatographic (HPLC) method has been developed for the determination of epimedin C in rat plasma and applied to a pharmacokinetic study in rats after administration of Herba Epimedii extract. After addition of carbamazepine as an internal standard plasma samples were extracted with ethyl acetate. HPLC analysis of the extracts was performed on a Hypersil ODS2 analytical column using acetonitrile -0.4% acetic acid (25:75, v/v) as the mobile phase. The UV detector was set at 260 nm. The standard curve was linear over the range 0.05-4.0 microg/mL. The lower limit of quantification was 0.05 microg/mL. The HPLC method developed could be easily applied to the determination and pharmacokinetic study of epimedin C in rat plasma after giving the animals Herba Epimedii extract.     

A note on behavioural responses of farm animals to ultrasound

Ultrasound emission is a method used to eliminate rats from buildings. This study was aimed at establishing whether immediate and strong behavioural reactions could be noticed in farm animals when exposed to ultrasonic sound from a device used for rat eradication.Behavioural reactions were recorded in horses, cattle, swine, sheep and poultry. The character of the behaviour reactions observed suggests that the animals experienced the pulsating ultrasound as a disturbance. It is concluded that ultrasound can not be regarded as suitable for rat eradication in stables for horses, cattle, sheep, swine or laying hens.     

An explanation of gastric hypersecretion in the pylorus-ligated rat

The hypersecretion of gastric acid in the pylorus-ligated rat has been shown to be of vagal origin. The present series of experiments were performed to identify the stimulus. The pyloric sphincter was ligated in a series of Sprague Dawley rats. Along with pylorus ligation, various other surgical manipulations were performed. Intestinal obstruction by ligation approximately 20 cm aboral to the cecum reduced unstimulated gastric secretion in the pylorus-ligated rat. However, perfusion of the lower small intestine with bicarbonate (143 mEq/L) stimulated secretion. Perfusion with either saline or deoxycholic acid (20 mEq/L) did not alter secretion. This supports a role for bicarbonate in the hypersecretion of gastric acid in the pylorus-ligated rat. The reflex appears to involve the myenteric plexus, since section of the pylorus seemed to attenuate gastric secretion. Plasma from animals with pylorus ligation, either alone or with intestinal ligation, equally inhibited gastric secretion. This suggests that while some factor inhibiting gastric secretion may be present, it appears to be unrelated to pylorus ligation.     

Removal of apoprotein-B-containing lipoproteins by plasmapheresis using immobilized phosphorylcholine-binding protein affinity adsorbent

Rat serum phosphorylcholine binding protein was earlier shown to bind lipoproteins containing apoproteins B and E from human very low and low density lipoproteins. The present studies were undertaken to show the effectiveness of rat serum phosphorylcholine-binding protein immobilized on Sepharose affinity column to remove apoprotein-B-containing lipoproteins from normal and hypercholesterolemic rabbit plasma, when used in a plasmapheresis system. The maximum in vitro binding of very low and low density lipoproteins from hypercholesterolemic rabbit plasma to the affinity adsorbent was Ca2+ dependent, and the cholesterol bound to the column at the optimum calcium concentration (2.5 mM) was 21% of the total plasma cholesterol applied. The in vivo binding of total cholesterol from normal and hypercholesterolemic rabbit plasma during plasmapheresis ranged from 0.22 to 7.7%. Total mass of cholesterol bound ranged from 3.86 and 27.52 mg at plasma cholesterol concentrations 13.8 and 282 mg/dL, respectively. Most (greater than 95%) of the bound cholesterol was associated with very low and low density lipoproteins. These studies show the ability of immobilized rat serum phosphorylcholine-binding protein to lower the atherogenic apoprotein-B-containing lipoproteins from plasma of hypercholesterolemic rabbits.     

Mechanical donor plasmapheresis using the Haemonetics Ultralite plasma collection system. 1. Collection of fresh plasma

In a clinical study altogether 449 machine donor plasmapheresis for collection of platelet poor fresh plasma were carried out using the new developed Haemonetics-Ultralite-Plasma-Collection-System. The average time of donation for 600 g of plasma amounted to 36 min. In comparison to other automated plasmapheresis-systems an effective plasma flow is recorded for the Ultralite-machine. All plasmapheresis procedures were well tolerated by the donors. The collected plasma is equivalent to the requirements for fresh frozen plasma. Complications due to the device or donors are small with 2.9% of the performed procedures.     

Temporal progression and extent of the return of sensation in the foot provided by the saphenous nerve after sciatic nerve transection and repair in the rat - implications for nociceptive assessments

Sensory testing, by providing stimuli for nociceptors of the foot, is a popular method of evaluating sensory regeneration after damage to the sciatic nerve in the rat. In the following study, 20 rats were submitted to double transection of the sciatic nerve. The subsequent 14 mm gap was repaired through guidance interponation. In order to evaluate nerve regeneration, sensory testing was performed additionally to other methods, which included motor testing, morphometry, and electron microscopic assessments of nerves. Somatosensory testing revealed that all animals exhibited next to the same amount of sensory reinnervation on their foot regardless of their experimental group. In motor tests, however, two out of the three experimental groups did not improve at all. These groups also failed to show neural regrowth in morphometric and electron microscopic assessments of the associated nerve. Retrograde tracing was able to prove the saphenous nerve as an alternative source of sensory reinnervation in animals with failed sciatic regeneration. This means that results of sensory testing in the rat should be treated with caution, taking into account the areas tested and the likelihood that in these areas saphenous sprouting could have taken place. Furthermore, it is strongly advised that somatosensory testing should be conducted only on toe 5.     

麻醉大鼠左心室插管新方法

目的：探索在0．014’’经皮冠状动脉（PTCA）指引导丝引导下行大鼠左心室插管的方法。方法：30只Wistar大鼠,先后在PTCA导丝引导经右侧颈外动脉,左侧颈外动脉插管至左心室并行血流动力学测定：结果：30只大鼠成功完成一次左心室重复插管,27只大鼠完成重复插管：结论：PTCA指引导丝引导下左心室插管安全并可重复操作。     

Vascularized muscle allografts and the role of cyclosporine

This study examined the fate of vascularized muscle allografts using a genetically defined rat model. Its purposes were (1) to analyze the histologic/immunologic responses, (2) to study the effect of cyclosporine on graft survival, and (3) to examine the possibility of inducing tolerance. In rats differing at a major histocompatibility locus, vascularized gastrocnemius muscle transplants were performed based on the sural branches of the femoral artery and vein. Forty-two animals studied were divided into three groups: Group 1, allografts, was treated without cyclosporine; Group 2, allografts, was administered continuous cyclosporine; and Group 3, allografts, was administered cyclosporine for 6 weeks only. Evaluation consisted of gross examination, H&E histology, and immunologic studies (MLC, CML, and complement-dependent 51Cr lysis assay). Lytic units (LU) were derived from the assays and served as the indicator of immune response. Group 1 animals had uniform rejection with intense cell-mediated response (LU 23 to 47) and low humoral response. Group 2 animals had viable allografts throughout with suppressed lytic unit values of 0 to 9 initially, which rose to 14 to 29 at 6 weeks despite continuous cyclosporine treatment. Group 3 animals showed rejection similar to the untreated animals. Autografts were performed as controls and survived indefinitely. Analysis of variance was significant at p less than 0.05. Using a reliable rat model for vascularized muscle allografts, we found that in transplantation across a major histocompatibility barrier, the initial immune response was primarily cell-mediated. Cyclosporine suppressed rejection only when given continuously, and short-term cyclosporine treatment did not induce a tolerant state. These data should be useful for future studies of vascularized muscle allografts.     

疟疾患者丙型肝炎病毒感染原因的血清学研究

本文报道了９７例疟疾患者丙型肝炎病毒（ＨＣＶ）感染的原因。发现疟疾患者抗－ＨＣＶ阳性率为７１．１３％,其中有单采血浆还输血细胞（下称单采浆）献血史者为８９．７１％,有受血史者为６４．２９％,既无单采浆史又无受血史者无一例抗－ＨＣＶ阳性。有单采浆史的疟疾患者与同村非疟疾的单采浆献血者相比,抗－ＨＣＶ阳性率无显著不同,且二者均显著高于同村既无单采浆史又无受血史的非疟疾人群。在无单采浆史和受血史人群中,疟疾病例和非病例抗－ＨＣＶ阳性率很低。说明有单采浆史的疟疾病例ＨＣＶ感染与单采浆有关,有受血史的疟疾病例ＨＣＶ感染与受血有关。对当地单采浆血站进行调查,发现在采血、分离血浆和血细胞还输过程中存在血液交叉污染,这是导致有单采浆史的疟疾病例ＨＣＶ感染的主要原因。     

Simulation of behavioral profiles in the plus-maze: A Classification and Regression Tree approach

This article introduces a simulation model of rat behavior in the elevated plus-maze, designed through a Decision trees approach using Classification and Regression algorithms. Starting from the analysis of the behavior performed by a sample of 18 Sprague-Dawley male rats, probabilistic rules describing behavioral patterns of the animals were extracted, and were used as the basis of the model computations. The model adequacy was tested by contrasting a simulated sample against an independent sample of real animals. Statistical tests showed that the simulated sample exhibits similar behaviors to those displayed by the real animals, both in terms of the number of entries to open and close arms as well as in terms of the time spent by the animals in those arms. However, the performance of the model in parameters related to the behavioral patterns was partially satisfactory. Given that previous attempts in the literature have neither include this kind of patterns nor the time as a crucial model parameter, the present model offers a suitable alternative for the computational simulation of this paradigm. Compared with antecedent models, the present simulation produced similar or better results in all the considered parameters. Beyond the goal of establish an appropriate simulational model, extracted rules also reveal important regularities associated to the rat behavior previously ignored by other models, i.e. that specific rat behaviors in the elevated plus-maze are time dependent. These and other important considerations to improve the model performance are discussed.     

Recovery from Goodpasture's syndrome after immunosuppressive treatment and plasmapheresis.

A patient with Goodpasture''s syndrome has recovered after treatment with immunosuppressive drugs (cyclophosphamide and prednisolone) and removal of circulating antibodies by plasma exchange. This was performed on seven occasions and seems to have hastened the decline in circulating antibody levels. Undertaken early in the course of the disease plasmapheresis could prove a useful addition to its therapy.     

Liquid biopsy by NGS: Differential presence of exons (DPE) is related to metastatic potential in a colon-cancer model in the rat

Differential presence of exons (DPE) is a method of interpretation of exome sequencing, which has been proposed to design a predictive algorithm with clinical value in patients with colorectal cancer (CRC). The goal of the present study was to examine the reproducibility in a rat model of metastatic colon cancer. DHD/K12-TRb cells were injected in syngenic immunocompetent BD-IX rats. Cells were from two stocks with low and normal metastatic potential, and injected into two separate groups of rats. Five to ten weeks after injection, blood samples were taken prior euthanasia and whole exome sequencing performed. Through DPE analysis, we identified a set of exons whose differential presence in plasma allowed us to compare both groups of tumor-bearing animals. A verification test was performed to confirm that the algorithm was able to classify extracted samples into their corresponding groups of origin. The highest mean probability was 0.8954. In conclusion, the DPE analysis in tumor-bearing animals was able to discriminate between different disease status, which fully supports previous results in CRC patients.