Miltefosine (Impavido): the first oral treatment against leishmaniasis

Miltefosine is a novel antileishmanial drug that has significant selectivity in both in vitro and in vivo models. Clinical efficacy was demonstrated for the treatment of visceral leishmaniasis with the advantage of oral administration over the currently recommended antileishmanial drugs that require parenteral administration. Miltefosine produces high cure rates also in patients resistant to the standard antimonial therapy.     

Interepithelial cells of the oral mucosa in mice

Summary Non-epithelial mesenchymal and neuroectodermal cells occur between the keratinocytes in the stratified squamous epithelium of the oral mucosa. These cells cannot be classified adequately by light microscopy. In the present study the oral mucosa of the lip, cheek and tongue of 50 mice were studied by light and electron microscopy. 3,025 mononuclear interepithelial cells were documented and analysed.Monocytogenic macrophages, plasma cells and mast cells were not found interepithelially and cannot be regarded as a regular constituent of the epithelium. Only a few neuroectodermal cells — in mice these are exclusively Merkel cells, with no melanocytes — were localized in the epithelium. The majority of the interepithelial cell population is made up of lymphocytes (22.8%) and Langerhans cells (56.8%). They are an integral constituent of the epithelium. Lymphocytes with rounded and indented nuclei can be identified. The larger and dendritic Langerhans cells are a specific cell of squamous epithelium and also occur in the oral mucosa. Not all cells which feature the cytological characteristics of Langerhans cells contain Langerhans or Birbeck granules. Accordingly these granules cannot be considered an exclusive identification characteristic. Two types of Langerhans cells can be differentiated. 80.9% have the more or less typical appearance known from the epidermis and were termed macrophagocytoid Langerhans cells. The nuclei are irregularly indented and moderately heterochromatic. 19.1% possessed conspicuous large, spherical, euchromatic nuclei and an electron-lucent cytoplasm. These were termed reticuloid Langerhans cells. About 20% of the interepithelial cell population could not be identified, neither as typical lymphocytes nor as Langerhans cells. These were small to medium sized cells with deeply indented cerebriform strongly heterochromatic nuclei. They are similar to the Sézary cells or mycosis fungoides cells of epidermotropic human T-cell lymphomas. The lymphocytic nature of these cells has been confirmed. It seems likely that differentiation of lymphocytes to cerebriform cells occurs within the epithelium. It is further discussed whether cerebriform cells are precursors of Langerhans cells, a conclusion suggested morphologically by transitional forms. This would imply that Langerhans cells originate from lymphocytes, and that the cerebriform cell is an intermediate step of differentiation. The microenvironment of the squamous epithelium may play a role in the process of differentiation, which could explain the epitheliotropy of lymphocytes. The possibility is considered that Langerhans cells and interdigitating reticulum cells of the T-cell area of lymph nodes are identical. The close functional cooperation of Langerhans cells, lymphocytes, and interdigitating reticulum cells in immunological defenses against external antigens is discussed.The authors wish to express their sincere appreciation to Miss P. Starck and Miss I. Brandt for invaluable technical assistance in this project.     

老年人口腔白色念珠菌的分布与基因分型研究

目的研究健康老年人口腔白色念珠菌的分布、基因型特点及基因型特点与白色念珠菌分布的相关性。方法来自成都地区212例老年人分为4组：A1（男性，有义齿）；A2（男性，无义齿）；B1（女性，有义齿）和B2（女性，无义齿）。CHROMagar Candida^TM鉴定培养基、碳水化合物同化反应鉴定体系（API 20C AUX）和随机扩增片段多态性分析（randomly amplified polymorphic DNA assays，RAPD）鉴定白色念珠菌。RAPD分析健康老年人口腔白色念珠菌分离株的基因型特征。统计学分析比较不同分组健康老年人口腔白色念珠菌基因型之间的差异。结果212例受检个体中检出89株白色念珠菌（42％），A1、A2、B1、B2白色念珠菌检出率分别为56．2％、21．3％、56．6％、38％。A1组与A2组白色念珠菌检出率差异有统计学意义，P〈0．01。以JWFP和NA为随机引物的RAPD分析将白色念珠菌分为5型。RAPD分析基因型构成在A1组与A2组之间比较差异有统计学意义，P〈0．05，A1组主要以A型为主。结论健康老年人口腔白色念珠菌的检出率与义齿修复相关。义齿修复可能促进具有特定基因型特点的白色念珠菌检出率增高。     

Mechanoreceptor activity from the human face and oral mucosa

Summary The feasibility of adopting the microneurography technique (Vallbo and Hagbarth 1968) as a tool to investigate the mechanoreceptive innervation of peri- and intra-oral tissues was explored. Multi-unit activity and impulses in single nerve fibers were recorded from the infraorbital nerve in healthy volunteers. The innervation territories of individual nerve fascicles were mapped. These varied considerably but most fascicle fields comprised the corner of the mouth. Twenty-four single mechanoreceptive units were recorded. Eighteen innervated the skin of the face, and six innervated the mucous membranes of the lips or cheeks. A majority of the mechanoreceptive afferent units were slowly adapting with small and well defined receptive fields. It is suggested that the various slowly adapting responses may originate from two different types of afferent units. No afferents showed response properties similar to typical Pacinian-corpuscle afferents.     

Proliferating cell nuclear antigen in malignant and pre-malignant lesions of epithelial origin in the oral cavity and the skin: an immunohistochemical study

Summary Proliferating cell nuclear antigen (PCNA) is a nuclear protein synthesized in the late G₁ and S phase of the cell cycle and immunohistochemical detection of the protein represents a useful marker for the proliferating fraction of cells in tissue specimens. A series of malignant and pre-malignant lesions of the oral cavity and skin were evaluated by the streptavidin biotin immunoperoxidase method for detection of this protein. Monoclonal anti-PCNA antibody (PC 10) labelled proliferating cells in all cases with varying intensity of nuclear staining. In squamous cell carcinoma (n=48), PCNA positivity correlated with the differentiation and atypia of the tumour cells; however, in poorly differentiated tumours, the relationship between PCNA expression and proliferation was lost. Basal cell carcinoma showed an increased growth fraction in tiny epithelial nests (mean 43.8, SD 6.0,n=20) than in neoplastic basal cells (mean 30.1, SD 6.9,n=8). The growth fractions were significantly higher in the pre-malignant lesions (leukoplakia, mean 22.3, SD 7.7,n=14; Bowen's disease, mean 45.2, SD 11.7,n=12; senile keratosis, mean 41.2, SD 7.0,n=12) than in the normal mucosa (mean 9.8, SD 4.9,n=10), suggesting that cellular growth fractions correlate with the degree of dysplasia in pre-malignant lesions.     

The defined attenuated Listeria monocytogenes Δmpl2 mutant is an effective oral vaccine carrier to trigger a long-lasting immune response against a mouse fibrosarcoma

Listeria monocytogenes has been proposed as a carrier to elicit major histocompatibility complex class-I restricted immune responses able to protect against tumor challenge. In this study the properties of the attenuated L. monocytogenes Δmpl2 mutant has been evaluated in vivo against a highly aggressive mouse fibrosarcoma which expresses β-galactosidase (β-gal) as a tumor-associated antigen (TAA). Immunization with the vaccine prototypes resulted in both elicitation of specific antibodies and generation of cytotoxic lymphocytes (CTL). Oral vaccination protected 55–64% of the immunized animals from tumor take (p < 0.01) and strongly reduced the average size of the tumor in the other 34–45% (p < 0.01). Vaccinated mice developed a long-lasting response, which resulted in 100% protection from a subsequent tumor challenge. Substitution of the whole TAA by its CTL-defined immunodominant epitope resulted in 43% protection, suggesting a contribution of the humoral response to the observed antitumor effect. No statistically significant differences were observed in the antitumor response when mice were immunized with strains expressing the immunodominant TAA epitope in the context of carrier proteins which were either exported or restricted to the bacterial cytoplasm. This suggests that the topology of the recombinant antigen does not play a major role in the outcome of the protective response.     

Intermediate-term toxicity of repeated orally administered doses of the anti-malarial β-artemether in dogs

The artemisinin derivative beta-artemether, an anti-malarial, was evaluated for its toxicity and tolerability in a 2-week, multiple-dose study in dogs. Eight beagle dogs (4 females, 4 males) were given beta-artemether by oral gavage 3 times daily at 45 mg/kg/dosing (a total daily dose-level of 135 mg/kg) for 2 weeks. This beta-artemether dose regime was well tolerated. Body weight changes were normal although feed consumption during the treatment period reduced compared to that of the pre-trial period. Clinical signs were transient spells of soft to liquid feces. On completion of the treatment period, the animals were sacrificed and submitted to a full macroscopic post-mortem examination. Designated organs were weighed and a complete light microscopic examination was performed on 43 selected tissues from 1 animal per sex, and on the liver, kidneys, thymus, mandibular lymph nodes and lungs of the three other animals per sex. Major findings were high liver weight and histopathologic findings of slight diffuse hepatocellular hypertrophy and distal tubular dilatation, together with flattened epithelium, in the kidneys. With the dose regime used in this trial beta-artemether produced no clinical or apparent histopathological signs of neurotoxicity in dogs.     

The reproducibility of the oral glucose tolerance test over long (5 years) and short periods (1 week)

Summary Three oral glucose tolerance tests (oGTT) have been performed in 312 non-diabetic relatives of diabetics over a period of 10 years. In a second study 6 identical oGTT's have been performed at weekly intervals in 55 individuals. In this study the variance, calculated from the logarithmic values, increased in the following order: fasting (0.026), 1 h (0.035), 2 h (0.044) and 3 h values (0.047). The sum of the 1 h and 2 h values showed the lowest variance (0.024). No significant difference of the variances was found in the 43 individuals in whom both the long-term and the short-term studies have been performed. Thus, a great proportion of the total variance of glucose observed over longer periods only represents a random variation. This random variation is much higher than most other factors which might influence the result of an oGTT. A diagnosis based on a single oGTT is of only limited value.Supported by a grant from Deutsche Forschungsgemeinschaft (Ko 457/8)     

Representation of the body in the lateral striatum of the freely moving rat: single neurons related to licking

This study examined the relationship of single-neuron activity (n = 739), recorded from the lateral striatum of freely moving rats, to oral movements involved in licking single drops of liquid. Certain neurons (n = 74) fired specifically in relation to licking. Their firing rates increased during licking, but remained near zero in the absence of licking, throughout a full sensorimotor examination of the remainder of the orofacial area and all other body parts. Another category of neurons (n = 17) fired during licking but also fired in the absence of licking, during one or more other orofacial sensorimotor function(s). Lick-related neurons were located in the lateral striatum, throughout the entire anterior-posterior range studied (from +1.5 to -1.5 mm anterior-posterior, A-P, bregma = 0). Summed over the full A–P range, they were located significantly ventral to representations of the trunk and limbs. These findings extend the characterization of the somatotopic organization exhibited by lateral striatal neurons in the rat, to include representation of oral functions, consistent with converging evidence regarding the functional organization of the striatum.     

抗癌生物活性肽对人乳腺癌nm231细胞的增殖抑制作用

 目的 探讨抗癌生物活性肽（ACBP）对人乳腺癌 nm231细胞的作用及其机制。 方法 nm231 细胞经不同浓度（0.05、0.10、0.20、 0.25 µg/ml）ACBP 作用 72 h，以噻唑蓝（MTT）法测定细胞增殖活性。以 0.25 µg/ml 的 ACBP 分别作用于 nm231 细胞 4、6、24、48、72 h，行光镜和透射电镜（作用 48 h 细胞）观察。应用 DNA 凝胶电泳和磷脂结合蛋白 V（Annexin V，AV）/碘化丙啶（PI）双标记染色流式细胞术等方法，观察 0.25 µg/ml 的 ACBP 作用不同时间对nm231 细胞凋亡发生及作用 48 h 对细胞周期的影响。以上各项检测均设以 RPMI 1640 培养液取代 ACBP 的对照组。 结果 浓度为 0.1 µg/ml 的 ACBP 即对 nm231 细胞的增殖有明显抑制作用，抑制率为 10.3%，抑制作用具有浓度依赖性，ACBP 浓度为 0.25 µg/ml 时抑制率达 35.1%。光镜观察显示，经 0.25 µg/ml 的 ACBP 作用 24 h，细胞出现凋亡特征；作用 48 h，光镜及电镜下均可见大量的典型凋亡细胞。DNA 凝胶电泳显示，经 0.25 µg/ml 的ACBP 作用 24 h 的细胞出现 DNA 断裂；作用 48 h 的细胞出现典型的梯形电泳图谱。流式细胞术分析显示，ACBP 作用后AV（+）/ PI（－）细胞和 AV（+）/ PI（+）细胞比例均随培养时间延长而增大；作用 48 h 的 nm231细胞 G0/1 期细胞比例高于对照组（P < 0.01），而细胞增殖指数低于对照组（P < 0.01）。 结论 ACBP 可抑制 nm231 细胞的增殖，其机制与抑制nm231 细胞的 DNA 合成和诱导细胞凋亡相关。