刺猬的皮肌及其神经支配

刺猬的皮肤,包括皮肤肌和皮下脂肪,是一个质量很大的器官,平均占体重43形,最多可达57％以上。刺猬的皮肌,如果不是动物界中最发达的,也是非常发达的,尤其环状皮肌带约占体重11％(赵以炳等1958)。在功能上,刺猬的皮肌是重要的生理性体温调节器官,背面带针刺的部分有保温御寒作用,腹部有散热机能(赵以炳等1950a)。清醒的刺猬当遇到强敌或其它干扰时,常蜷缩成带剌的球。不活动的冬眠刺猬也取同样姿势,以防侵害。可以说,蜷缩是一种主动的保护性行为,这种强烈的蜷缩主要是由于环状皮肌带持续有力的收缩。尤其令人惊奇的是冬眠时的蜷缩,这是在一般生理活动明显降低的     

Two new cases of cutaneous alternariosis with a review of the literature

Summary Two cases of cutaneous phaeohyphomycosis due to Alternaria tenuissima in patients affected with primitive myeloproliferative syndrome and lymphocytic lymphoma respectively are reported.Following a review of the specific literature, the authors discuss the etiopathogenic mechanisms, the clinical and histologic aspects of the lesions and the therapeutic problems.     

Bionomics of phlebotomine sandflies in the Galilee focus of cutaneous leishmaniasis in northern Israel

The bionomics of phlebotomine sandflies (Diptera: Psychodidae) were studied for three years (2001-2003) in the Galilee focus of cutaneous leishmaniasis in northern Israel, where the causative Leishmania tropica (Kinetoplastida: Trypanosomatidae) is transmitted by Phlebotomus (Adlerius) arabicus Theodor and Phlebotomus (Paraphlebotomus) sergenti Parrot, comprising 22% and 8%, respectively, of the local sandfly fauna sampled by light traps. The predominant species overall was Phlebotomus (Larroussius) tobbi Adler & Theodor (51%) with lesser numbers of Phlebotomus (Adlerius) simici Theodor (11%), Phlebotomus (Larroussius) syriacus Adler & Theodor (5%), Phlebotomus (Larroussius) perfiliewi Perfil'ev (3%) and Phlebotomus (Phlebotomus) papatasi Scopoli (0.05%). Sandfly adult populations were prevalent from April to November and peaked between June and August, being more abundant through the summer in irrigated habitats, such as gardens and orchards, than in open grassland. Of the two cutaneous leishmaniasis vectors, P. sergenti preferred boulder mounds located at the outskirts of settlements, whereas P. arabicus was more abundant overall and near houses in particular. Females of all these sandfly species displayed a peak of activity after sunset (20.00-22.00 hours), whereas activity of males persisted longer through the night. Another slight increase in activity was noted before dawn (02.00-04.00 hours). Phlebotomus arabicus appears to be the main vector of L. tropica in the Galilee focus, due to its denser populations, more endophily and preference for peridomestic habitats than shown by P. sergenti in northern Israel.     

Examination of variables in the vaccination of mice against cutaneous leishmaniasis using living avirulent cloned lines and killed promastigotes of Leishmania major

Mitchell G. F., Handman E. and Spithill T. W. 1985. Examination of variables in the vaccination of mice against cutaneous leishmaniasis using living avirulent cloned lines and killed promastigotes of Leishmania major. International Journal for Parasitology15: 677–684. In vaccination experiments not involving adjuvants, genetically-susceptible mice were injected with living avirulent cloned promastigotes of Leishmania major or killed promastigotes prior to cutaneous challenge with virulent cloned promastigotes. Emphasis was placed on aspects that may contribute to marked variability between experiments and between laboratories in vaccination of mice against cutaneous leishmaniasis. One variable, the challenge promastigotes, was shown to be important in that cloned virulent parasites (V121) were less pathogenic in terms of rate of cutaneous lesion development, than the parental isolate LRC-L137 when low doses of promastigotes were used and particularly when harvested from the log phase of culture. It is likely that avirulent parasites in mixed isolates can increase the rate of lesion development after cutaneous deposition. As reported previously, intraperitoneal, and more particularly intravenous injections of living avirulent cloned parasites (A12) increase resistance in mice. Most importantly, a difference has been demonstrated in the vaccinating efficacy of killed promastigotes of various isolates injected intravenously. This implies that certain isolates of L. major (e.g. the “Moshkovsky strain”) express “host-protective antigens” at higher levels, or in a qualitatively different manner, than other isolates (e.g. LRC-L137). The finding will greatly facilitate the identification of vaccine antigens in this system using immunochemical and gene cloning approaches.     

Body Site Variation of Cool Perception Thresholds,with Observations on Paradoxical Heat

Thresholds for the perception of coolness and heat pain were determined in sessions that randomly intermixed temperature increases and decreases. Four body sites were tested bilaterally: thenar eminence of the hand, plantar surface of the foot, dorsolateral forearm, and lateral calf. Coolness thresholds were lowest for the hand, intermediate for the forearm, and highest for the leg and foot. Laterality differences were not statistically significant.

In 34% of the sessions, subjects did not consistently report cool or cold sensations with detectable temperatue decreases. When they did not report cool or cold, they most often reported heat or pain, thus exhibiting the phenomenon of “paradoxical heat”. There were significantly more paradoxical heat responses when cooling stimuli were intermixed with painfully hot stimuli than when they were intermixed with only warm stimuli.

There was no significant correlation observed between thresholds for coolness and heat pain, either across body sites or across subjects at any single body site. This result implies that the various factors relevant to thermal sensitivity (i.e., thermal properties of the epidermis, innervation density) are differentially important for cool versus heat pain perception.     

Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health disorders such as chronic wounds. We report the development of a dual-mode imaging system for non-invasive and non-contact imaging of cutaneous tissue oxygenation and vascular function. The imaging system integrated an infrared camera, a CCD camera, a liquid crystal tunable filter and a high intensity fiber light source. A Labview interface was programmed for equipment control, synchronization, image acquisition, processing, and visualization. Multispectral images captured by the CCD camera were used to reconstruct the tissue oxygenation map. Dynamic thermographic images captured by the infrared camera were used to reconstruct the vascular function map. Cutaneous tissue oxygenation and vascular function images were co-registered through fiduciary markers. The performance characteristics of the dual-mode image system were tested in humans.     

Kinetics and localization of parasite-specific IgE in Paragonimus ohirai-infected rats

Ikeda T., Oikawa Y. and Fujita K. 1982. Kinetics and localization of parasite-specific IgE in Paragonimus ohirai-infected rats. International Journal for Parasitology12: 395–398. In Wistar rats infected with Paragonimus ohirai (P.O.), P.O.-specific IgE responses of the mesenteric and mediastinal lymph nodes and spleen were determined by homologous adoptive cutaneous anaphylaxis (ACA) assay since P.o. -specific IgGa was not detected by either 2 h or 4 h PCA. Intraperitoneal (i.p.) infection with metacereariae elicited similar patterns of ACA response in the three lymphoid tissues examined, with the mediastinal lymph node giving the highest response. ACA positive cells were detected 2 weeks after infection, peaked at 3 weeks and then declined. These kinetics of ACA responses nearly paralleled the kinetics of serum P.o.-specific IgE titre. In intrapleural infection with metacereariae, on the other hand, the mediastinal lymph node gave a high ACA response comparable to the lymph node in i.p. infection, but the mesenteric lymph node and spleen gave negligible ACA responses. In infection established by i.p. transplantation of 4–5-week-old worms, only the mediastinal lymph node of the three lymphoid tissues responded and its response was at a low ACA level. The level of serum P.O.-specific IgE was much lower in the above two infections than in i.p. infection with metacercariae.     

Fritillaria ussuriensis Extract Inhibits the Production of Inflammatory Cytokine and MAPKs in Mast Cells

Fritillaria ussuriensis (FU, derived from the bulbs of various species of the genus Fritillaria, including Fritillaria thunbergii Miq.) is used in herbal medicine to treat conditions such as eczema, skin burns, and frostbite. In this study, we investigated the mechanism of the anti-allergy effect of FU. FU extract (80 mg/kg), orally administered to Sprague-Dawley (SD) rats, significantly inhibited the passive cutaneous anaphylaxis (PCA) reaction. It inhibited the compound 48/80-induced release of histamine from rat peritoneal mast cells in a concentration-dependent manner. Significant inhibitory effects of the FU extract on IL-6, IL-8, and TNF-α (1, 10, and 100 μg/mL) were observed in HMC-1 cells. Treatment with FU attenuated PMA plus A23187-induced phosphorylation of all three MAPKs, especially at concentrations of 10 and 100 μg/mL. Further, it (80 mg/kg) led to significant inhibition of mast-cell accumulation in ear tissue at the chronic phase. These results indicate that it inhibits allergic reactions.     

Leishmania donovani: identification of novel vaccine candidates using human reactive sera and cell lines

Leishmaniasis is a complex of diseases caused by protozoan parasites belonging to the genus Leishmania. The development of specific resistance against re-infection after cure suggests that a vaccine approach is feasible. Various studies in humans and experimental animals strongly suggest that Th1 type of cell-mediated immune response is important for protection against the disease. A defined antigen that could elicit a specific T-cell-mediated immune response in the host would be an ideal candidate for the vaccine against this parasite. In order to select a candidate antigen, we established a screening system to identify the recombinant clone, expressing antigen having T-cell epitopes from a cDNA library. We screened the library using an established Leishmania specific cell line (LSCL) from a naive healthy human subject. The cell line with predominantly CD4+ cells behaved in a Leishmania specific manner. Fifty-two immuno-reactive clones were screened against the LSCL in vitro and we identified three cDNA clones expressing recombinant antigens that could induce proliferation of these cells to produce INFgamma. The protective efficacy of one of these recombinant proteins was investigated in a hamster model of experimental visceral leishmaniasis and showed protection against a virulent challenge. The identified antigens might be potential candidates for vaccine against Leishmania.