Extraintestinal infection of Helicobacter cinaedi induced by oral administration to Balb/c mice

Although Helicobacter cinaedi was initially considered an opportunistic pathogen in immunocompromised patients, it was later shown to also infect immunocompetent and healthy individuals. Sporadic bacteremia due to H. cinaedi has frequently been reported; however, whether the bacterium can be translocated after passage through the intestinal mucosa remains unclear. In the present study, a preclinical small animal model that faithfully reproduces H. cinaedi infection in humans was developed. Balb/c male mice were orally inoculated with a single dose of 6.8 × 10⁷ CFU of a human clinical H. cinaedi strain. The organism persistently colonized the intestinal tract of the mice, particularly the cecum and colon, for at least 56 days, and the bacteria were excreted in the feces. Although inoculated bacteria were recovered from the spleen, liver, kidney, lung, bladder and mesenteric lymph nodes during the first 2 weeks of bacteremia, the organism was not isolated from these organs after 4 weeks, suggesting that complement‐ and antibody‐mediated serum sensitivity account for the relatively low frequency of systemic infection. However, H. cinaedi was isolated from the biceps femoris, triceps branchii, latissimus dorsi, and trapezius muscles beyond 2 weeks after infection and after production of specific anti‐H. cinaedi IgM and IgG antibodies. The present findings suggest that experimental infection of Balb/c mice with H. cinaedi may be a useful model for further studies of H. cinaedi pathogenesis, prophylaxis or therapeutic interventions in vivo.     

Prevention of vertical transfer of Neospora caninum in BALB/c mice by vaccination

Neosporosis is an important cause of abortion and neonatal morbidity in dairy cattle. The disease is caused by Neospora caninum, an intracellular protozoan parasite. In this report, we describe the use of a mouse model in the preliminary evaluation of vaccination as a means to prevent vertical transfer of N. caninum. Parasites present in the tissues of the offspring were detected using an N. caninum-specific polymerase chain reaction assay. Immunization of dams with a single inoculation of a crude lysate of N. caninum tachyzoites appeared to induce complete protection against infection of the offspring.     

Longevity of Echinostoma caproni in Balb/c mice

This study used Balb/c mice to examine the longevity of Echinostoma caproni. Five mice each exposed to 75 encysted metacercariae (cysts) were necropsied at 23 weeks postinfection (PI) (160 days PI). Two of the 5 were infected with a total of 33 worms; 23 in one mouse and 10 in the other. Body and organ area measurements showed that these worms were robust and normal in appearance. No signs of atrophy of any of the genital structures were observed. The mean +/- SE of eggs/uterus per worm (n = 10) was 243 +/- 6. This strain of mouse will be suitable to study the effect of long-term survival on the host-parasite relationship of E. caproni in Balb/c mice.     

人脐带间充质干细胞在Balb/c裸鼠体内的分布情况研究

目的研究人脐带间充质干细胞（hUCMSCs）在BalB/c裸鼠体内的分布。 方法采用DiR标记hUCMSCs,以MTT法检测标记hUCMSCs体外培养的生长增殖,流式细胞术检测标记hUCMSCs的细胞表型,以诱导分化法检测标记hUCMSCs的成骨、成脂、成软骨诱导分化能力,小动物活体成像法检测DiR标记hUCMSCs尾静脉给药后在小鼠体内的分布情况。采用t检验对测得的hUCMSCs增殖数据进行统计分析。 结果0,24,48,72,96,120 h MTT法测得的DiR标记hUCMSCs吸光度值与未标记组相比差异无统计学意义,DiR标记对hUCMSCs细胞表型没有明显影响,对其成骨、成脂、成软骨多向诱导分化能力没有影响,DiR标记hUCMSCs尾静脉给药后,荧光首先分布于肺脏,随时间逐渐迁移至肝脏和脾脏,最终归巢和分布于肝脏、脾脏和肺脏,荧光强度肝脏>脾脏>肺脏,随时间逐渐减弱,至4周时动物肝脏、脾脏和肺脏仍有荧光存在。 结论DiR标记不影响hUCMSCs体外增殖、细胞表型表达和多向诱导分化能力,DiR标记hUCMSCs尾静脉注射后首先分布在肺脏,存在明显的首过效应,然后逐渐迁移至肝脏和脾脏,主要分布和归巢在肝脏、脾脏和肺脏。     

Cutaneous leishmaniasis infection in Balb/c mice using a Leishmania tropica strain isolated from Turkey.

Leishmania tropica, which is endemic in Turkey, is the causative agent of cutaneous leishmaniasis. Leishmania tropica promastigotes (2 x 10(7)) isolated from a patient with dermal leishmaniasis and reproduced in NNN medium were inoculated subcutaneously into the footpads of 10 Balb/c mice. Cutaneous leishmaniasis developed on the footpads of 4 mice approximately 45 days later. Leishmania tropica amastigotes were observed in smear slides and then cultivated in NNN medium. Balb/c mice are a suitable laboratory model for this isolate of L. tropica and thus a source of amastigotes for studies on the immunology, chemotherapy, and pathogenicity of cutaneous leishmaniasis.     

Influence of sex hormones on Coxsackie B-3 virus infection in Balb/c mice

Background and “spontaneous” proliferation are terms often used for the proliferative activity normally exhibited by peripheral blood mononuclear cells (MNC) in vitro. In this report, we show that Interleukin-2 (IL-2) added to unfractionated MNC but not to isolated T or non-T cells significantly increased their proliferative activity. The cells responding to IL-2 stimulation from MNC were OKT3 positive lymphocytes. In addition, treatment of MNC with either a monoclonal anti-HLA-DR antibody (in the absence of C′) or Cyclosporin-A strongly suppressed the “background” whereas treatment of MNC with the 3A1 monoclonal anti-human T cell antibody did not modify “spontaneous” proliferation of these cells. IL-2 could not restore or increase the proliferative activity of MNC exposed to the anti-HLA-DR antibody or Cyclosporin-A while the T cell growth factor significantly enhanced proliferation of MNC cultured in the presence of the OKT4 antibody. Taken together these results strongly suggest that IL-2 responding T cells from MNC become sensitive to IL-2 by interacting with HLA-DR antigens on B lymphocytes and/or monocytes contained in MNC (resting T cells are Dr^?). By a similar mechanism we have previously shown that T cells acquire responsiveness to IL-2 in the autologous mixed lymphocyte reaction (AMLR). Since all the cells that participate in AMLR are present in MNC, we postulate that a “mini” AMLR taking place within MNC may explain the “spontaneous” proliferation of peripheral blood mononuclear cells.     

Hypothalamic-adenohypophyseal origin of reproductive failure in mice following chronic infection with Toxoplasma gondii

Mice chronically infected with Toxoplasma gondii exhibited reproductive failure characterized by a constant diestrous vaginal cytology and ovarian and uterine atrophy. Chronically infected mice were treated with 20 ng of D-Leu6-des-Gly-NH2-Pro-ethylamide (D-Leu6), a structural analog of luteinizing hormone-releasing hormone (LHRH), every 4 hr over a 12-hr period daily, for 3 days. Infected animals treated with D-Leu6 had greater pituitary weight (P less than 0.01), ovarian weight (P less than 0.01), and uterine weight (P less than 0.025), than did infected control mice treated with saline. In addition, a change in vaginal cytology to estrus, metestrus, and proestrus of the D-Leu6-treated animals was observed, although a contiguity of normal estrous cycles and reproductive function was not determined. Comparable basal levels of serum luteinizing hormone (LH) were seen in infected mice and uninfected normal mice. However, the infected animals demonstrated a decreased pituitary responsiveness to D-Leu6 when monitored at 60 (P less than 0.025) and 120 min (P less than 0.010) following intraperitoneal administration of a bolus of 200 ng of the analog. Thus, the observed reproductive failure involves the readily releasable pool of pituitary LH, since basal LH is similar in both groups, and appears to be due to a dysfunction of the hypothalamic-adenohypophyseal axis.     

Congenital transmission of experimental chronic toxoplasmosis in rats.

A 10% transplacental transmission rate was observed in litters from 89 Wistar rats chronically infected with Toxoplasmosis gondii, as judging from bioassays. The rats had been fed T. gondii 2 mo prior to mating. Six of 7 isolates of T. gondii were transplacentally transmitted. The frequency of transmission did not appear to be affected by the strain of T. gondii or the size of the inoculum.     

超声心动图评定雄性Balb/c小鼠心脏形态和功能

目的：应用超声心动图评定雄性Balb／c小鼠的心脏形态和功能。方法：应用13MHz线控阵超声探头检测27只Balb／c雄性小鼠心脏（周龄：5—7周）,超声检测后,进行戊巴比妥麻醉处死分离左室,测量湿重.结果：获得小鼠完整2维超声心动图,并记录雄性小鼠血流动力学参数：用M型超声心动图计算左室重量与左室湿重呈线性相关：y=1．15x＋3．26（r=0．80）。结论：超声心动图参数能够评定小鼠的心脏形态和功能。     

Bordetella pertussis respiratory infection in C57B1/6 and Balb/c mice: Pathophysiology and immune responses

A virulent clone of Bordetella pertussis, injected intranasally into C57B1/6 or Balb/c mice, induced a respiratory tract infection that mimicked the infectious process of whooping cough. The density of the inoculum influenced the kinetics of in vivo bacterial growth, as well as the associated leucocytosis, which were of equivalent intensity in both strains of mice. Convalescing mice became resistant to re-infection, but not to the effects of the leucocytosis-promoting factor of the pertussis toxin. Prominent immune response, associated with acquired resistance, was a delayed type hypersensitivity (DTH) reaction, the intensity of which depended upon the genotype of the mice when the eliciting antigen contained the pertussis toxin in a biologically active form. Intranasal infection of congenic mice may represent an improved quantitative test for reproducible measurement of virulence and immunogenicity of B. pertussis.     

噬菌体对黏质沙雷菌感染 BA LB／c小鼠的保护作用

本文旨在观察噬菌体对黏质沙雷菌感染小鼠的治疗作用,为噬菌体疗法应用于细菌性感染提供依据。以黏质沙雷菌为宿主菌,采用双层琼脂噬斑法从污水中分离和纯化裂解性噬菌体。将最小致死量的黏质沙雷菌经腹腔感染BALB／c小鼠后,立即腹腔注射不同剂量的噬菌体,观察动物的生存率并确定噬菌体的保护剂量。在动物感染后的不同时间（0、20、40、60和180 min ）观察噬菌体疗法对动物存活率的影响。将噬菌体和细菌同时或分别注射动物后,分析噬菌体在动物体内的药代动力学。结果显示,经噬斑法从污水中分离出1株裂解性噬菌体（命名为φSM9‐3Y ）,电镜观察发现该噬菌体属有尾噬菌体目肌尾噬菌体科。动物腹腔感染黏质沙雷菌并立即给予噬菌体后发现,当噬菌体的保护剂量为108 PFU／ml时,动物的存活率为100％。动物感染后40和60 min给予噬菌体（1010 PFU／ml）治疗,动物的存活率为60％。药代动力学表明,将噬菌体和细菌同时注入动物体内,在6 h内噬菌体的滴度维持在1010 PFU／ml。结果提示,噬菌体对黏质沙雷菌所致动物腹腔内感染的治疗是有效的,提示针对细菌性感染的噬菌体疗法具有潜在的应用价值。     

Experimental chronic pulmonary infection in mice caused by Klebsiella pneumoniae

Examination of mouse strain differences in susceptibility to experimental respiratory tract infection with Klebsiella pneumoniae 27 revealed that a chronic pulmonary infection model could be established using CBA/J mice. After 6 X 10(5) colony-forming units of K. pneumoniae 27 were inoculated into the lung, the bacterial counts in the lungs changed with time showing four different phases: initial decrease, regrowth, steady-state, and final increase leading to death. Throughout the course of the infection, the challenge bacteria were isolated mainly from the respiratory organs. Pulmonary gross lesions appeared on day 2 after infection and persisted thereafter. Lobar consolidation was the primary lesion and occurred mainly in the anterior and middle lobes of the right lung, and the median lobe. Mice began to die from 4 weeks after aerosol exposure. This model may be useful for investigating the pathogenesis of chronic pulmonary infection by Klebsiella and its therapy.     

Hematologic disease induced in BALB/c mice by a bcr-abl retrovirus is influenced by the infection conditions.

Irradiated mice reconstituted with bone marrow cells infected with a retrovirus carrying the bcr-abl oncogene of human chronic myeloid leukemia are subject to a range of neoplastic hematopoietic diseases, both myeloid and lymphoid. Comparison of DBA/2 and C57BL/6 mice has revealed a marked strain difference in susceptibility to the various tumor types. The present study, performed with BALB/c mice, indicates that the kinetics and nature of the induced disease can be modulated by the infection procedure, as well as the genetic background, and that retroviral regulatory sequences may influence the outcome. A distinctive clonal myeloproliferative disorder, somewhat akin to chronic myeloid leukemia but with prominent erythroid and mast cell components, as well as granulocytic excess, was characterized.     

Tissue distribution and antileishmanial activity of liposomised Amphotericin-B in Balb/c mice§

Antileishmanial activity and organ distribution of the antifungal drug Amphotericin-B in free and liposomised form have been studied in Balb/c mice infected withLeishmania donovani. Results indicate that Amphotericin-B in the liposomised form is significantly more active than the free form. This increase in the activity is perhaps related to the reduced drug toxicity rather than the altered drug distribution at the site of infection. CDRI communication No. 4789     

Immunoproteomic identification of biotransformed self-proteins from the livers of female Balb/c mice following chronic ethanol administration

Chronic alcohol consumption culminates in alcoholic hepatitis which is characterized by ballooning degeneration of hepatocytes and perivenous inflammation. The aldehydes produced by ethanol oxidation and lipid peroxidation form adducts with the hepatic proteins rendering them immunogenic and initiating an autoimmune response. The present study was designed to identify these immunoreactive hepatic proteins in ethanol-treated Balb/c mice. Liver cytosolic, mitochondrial, and microsomal proteins from the ethanol-treated and control female Balb/c mice were size fractionated on SDS-PAGE and immunoblotted with the sera from the individual animal. The immunoreactive proteins were identified using antimouse IgG antibody and characterized by MALDI-TOF. It is the first report demonstrating that 15 hepatic proteins show immunoreactivity following alcohol administration. The identified autoreactive proteins ranged in function from metabolism to cytoskeletal support. Remarkably, three key enzymes of ethanol metabolism, namely alcohol dehydrogenase, aldehyde dehydrogenase I and III as well as important antioxidant enzyme glutathione S-transferase were found to be autoreactive upon ethanol treatment. We conclude that ethanol treatment induces biotransformation of host proteins from almost every compartment of the cell, especially the enzymes involved in the detoxification of ethanolic insult being the major target for biotransformation. Hence, we propose that these proteins can be the potential candidates for the biomarker studies.     

Antimutagenicity of ursolic acid and oleanolic acid against doxorubicin-induced clastogenesis in Balb/c mice

Ursolic acid (UA) and oleanolic acid (OA) are triterpenoid compounds found in food, medicinal herbs and various other plants in free form or bound to glycosides. Both substances are known for their antimicrobial, hepatoprotective, anti-inflammatory, antiallergic, antiviral and cytotoxic activities. In the present study, we evaluated the antimutagenic potential of UA and OA using the micronucleus test in peripheral blood and bone marrow of Balb/c mice. The animals were divided into 10 treatment groups: mice treated with UA (80 mg/kg b.w.); OA (80 mg/kg b.w.); a mixture of UA and OA (80 mg/kg b.w.); the antineoplastic agent doxorubicin (DXR, 90 mg/kg b.w.); DMSO and DXR; UA and DXR; OA and DXR; UA, OA and DXR, and negative and solvent controls. UA, OA and a mixture of UA and OA were administered to the animals by gavage, followed by the intraperitoneal injection of DXR. The results showed a significant reduction in micronucleus frequency in the groups concomitantly treated with the triterpenoid compounds and DXR compared to that treated with DXR alone. The present results demonstrate the antimutagenic activity of UA and OA under the experimental conditions used in this study.     

Inhibitory effects of Azadirachta indica on DMBA-induced skin carcinogenesis in Balb/c mice

Male Balb/c mice were divided into four groups on the basis of their respective treatments wherein mice of Group I served as controls. For induction of skin tumors, mice of Group II and IV were injected sub-cutaneously with 7,12-dimethylbenz(a)anthracene (DMBA). Mice of Group III and IV were administered aqueous Azadirachta indica leaf extract (AAILE) thrice a week throughout the experiment. After 14 weeks of the first DMBA injection, Group II and IV mice developed tumors. In the tumor-bearing mice that received AAILE (Group IV), a significant reduction in mean tumor burden and tumor volume was observed. The tumors were confirmed to be papillomas and interestingly, the extent of hyper-chromatia was observed to be much more in skin tumors of Group II mice vis a vis the mice receiving AAILE. An increase in the extent of lipid peroxidation was observed in tumorous tissue of Group IV when compared to that of Group II mice. Glutathione (GSH) content and the activities of GSH-based antioxidant enzymes viz. glutathione peroxidase (GPx) and glutathione reductase (GR) increased significantly in the skin tissues of all the groups of mice when compared to control counterparts. Catalase activity was found to decrease significantly in the skin of mice, which received AAILE treatment only (Group III). Activity of super-oxide dismutase (SOD) decreased significantly in all the tumorous tissues (Group II and IV mice). In light of the above observations, the role of AAILE in inhibition of DMBA-induced skin carcinogenesis is discussed in the present study.