Lack of spontaneous activity of cutaneous spinal dorsal horn neurons in awake, drug-free, spinally transected cats

Extracellular single-unit activity was recorded from neurons with cutaneous input in the dorsal horn of the spinal cord (L4-L6) of awake, drug-free cats before (for several weeks) and after (day 1 through day 7) cord transection (T12). The spontaneous activity of the neurons was minimal or nonexistent in both recording conditions. The lack of spontaneous activity following spinal cord transection contrasts sharply with activity recorded in acute spinal-cord transected preparations in which high rates of spontaneous activity have been reported. This discrepancy may reflect an important difference between the chronic, awake, drug-free and acute preparations.     

Electron microscopic evidence for the association of M 2 protein with the influenza virion

Summary Immunogold electron microscopy revealed that site-specific antibodies elicited by a synthetic peptide representing the N-terminal sequence (residues 2–10) of influenza virus M 2 protein were capable of binding to the surface of virions. Antibody binding was observed with two human influenza virus strains but not with an avian virus strain which has amino acid substitutions in the appropriate sequence of M 2. These results provide direct evidence for the presence of M 2 in the influenza virion.     

抗体阴性重症肌无力发病与凝集素之间关系研究

借助研究抗体阴性重症肌无力（ＭＧ）发病与凝集素之间的关系，以阐明其发病过程是否与凝集素有关。方法观察伴刀豆球蛋白Ａ（ＣｏｎＡ）和麦胚凝集素（Ｔｒｉｔｉｃｕｍ）及其凝集素－糖复合物对ＴＥ６７１细胞表达的乙酰胆碱受体（ＡＣｈＲ）功能的作用，以及对α－ＢｕＴｘ结合试验的影响。结果有两种凝集素对ＡＣｈＲ功能均有抑制作用，抑制率（％）分别为５４±１４（ｎ＝１１）和４７±１６（ｎ＝１０），此作用可被３种糖抑制，抑制率（％）分别为：９５±５（ｎ＝５）和８４±８（ｎ＝５）；６９±６（ｎ＝４）和６５±５（ｎ＝４）；３９±４（ｎ＝５）和５７±６（ｎ＝５）；ＣｏｎＡ抑制α－ＢｕＴｘ结合试验，而Ｔｒｉｔｉｃｕｍ则不能。结论Ｔｒｉｔｉｃｕｍ和抗体阴性ＭＧ患者非ＩｇＧ部分对ＡＣｈＲ功能和α－ＢｕＴｘ结合试验的作用类同或一致，表明抗体阴性ＭＧ患者非ＩｇＧ部分中的内源性Ｔｒｉｔｉｃｕｍ样糖蛋白在其发病过程中起重要作用。     

THE HISTOLOGIC FEATURES AND HISTOGENESIS OF MALIGNANT OVARIAN BRENNER TUMOR

Eight cases of malignant and 12 0f benign Bren- ner tumor are reported, patient ages ranged 31 69 and 39-53 years. The malignant tumor was bilateral in 6 0f 8 cases, and the benign in l of 12. The greatest diameter of the malignant tumors averaged around 11 cm, and the benign 10. Six of the malignant Brenner tumor patients died, one was lost to follow up, and one survived for 10 years. Pathologic and microscopic findings were pre- sented in some detail. Based on the analysis of the association between the histologic features and type of Mullerian epithelium, we believe that the so called Brenner tumor is in effect a tumor arising from the Mullerian epithelium with a tendency to differentiate into vaginocervical type epithelium.     

Influence of lecithin on mitochondrial DNA and age-related hearing loss.

OBJECTIVES: Lecithin is a polyunsaturated phosphatidylcholine (PPC), which are high energy functional and structural elements of all biologic membranes. PPC play a rate-limiting role in the activation of numerous membrane-located enzymes, including superoxide dismutase and glutathione, which are important antioxidants protecting cell membranes from damage by reactive oxygen species (ROS). ROS-induced damage to mitochondrial DNA may lead to reduced mitochondrial function in the cochlea and resultant hearing loss. STUDY DESIGN AND SETTING: The effects of lecithin on aging and age-associated hearing loss were studied in rats by measuring hearing sensitivities using auditory brainstem responses (ABR). In addition, mitochondrial function as a measure of aging was assessed by determining mitochondrial membrane potentials using flow cytometry and by amplifying mitochondrial DNA deletions associated with aging. Harlan-Fischer rats aged 18 to 20 months (n = 14) were divided into 2 groups. The experimental group was supplemented orally for 6 months with lecithin, a purified extract of soybean phospholipid (Nutritional Therapeutics, Allendale, NJ). RESULTS: The data obtained were compared with the control group. ABRs were recorded at 2-month intervals and showed significant preservation of hearing sensitivities in the treated subjects. Flow cytometry revealed significantly higher mitochondrial membrane potentials in the treated subjects, suggesting preserved mitochondrial function. Finally, the common aging mitochondrial DNA deletion (mtDNA(4834)) were amplified from brain and cochlear tissue including stria vascularis and auditory nerve. This specific deletion was found significantly less frequent in all tissues in the treated group compared with the controls. CONCLUSION: These experiments support our hypothesis and provide evidence that lecithin may preserve cochlear mitochondrial function and protect hearing loss associated with aging.     

Polyclonal and allergen-induced cytokine responses in children with elevated immunoglobulin E but no atopic disease

BACKGROUND: Reduced Th1 and elevated Th2 cytokine responses are considered to be a principal mechanism in the generation of the inflammation leading to the manifestations of atopic disease in the skin of atopic dermatitis and in the airways of asthma. If reduced Th1 and elevated Th2 responses are principal determinants of the manifestation of atopic disease it might be expected that subjects with established disease would exhibit differences in their cytokine profiles as compared with atopic patients without clinical disease. OBJECTIVE: To determine whether asymptomatic atopic children exhibit a cytokine imbalance similar to that seen in patients with established atopic disease or if they behave like non-atopic controls. Cytokine responses in a group of children with elevated IgE but no clinical manifestations of disease, atopic children with established disease and non-atopic controls were compared. METHODS: We examined allergen-induced (house dust mite, HDM, rye grass pollen and RYE) cytokine responses in parallel with polyclonal (staphylococcal enterotoxin B, SEB) cytokine responses in a group of children with elevated serum IgE levels without current or past evidence of atopic disease (median age 6.6 years) and compared these with a non-atopic control group (median age 6.5 years) and a group of children with atopic disease (median age 6.7 years). RESULTS: Symptomatic atopic children had reduced SEB-induced IFN-gamma and increased SEB-induced IL-4 and IL-5 as compared with non-atopic controls. In contrast, SEB-induced IFN-gamma, IL-4 and IL-5 production in asymptomatic atopics was not significantly different from the non-atopic control subjects. Allergen-induced Th1 (IFN-gamma) and Th2 (IL-5 and IL-13) cytokine production was increased in both symptomatic atopics and asymptomatic atopics when compared with non-atopic controls. CONCLUSION: The defect in polyclonally induced IFN-gamma production was associated with the clinical manifestation of atopic disease but not the atopic stateper se. This suggests that the global reduction in IFN-gamma is the key determinant of the development of overt atopic disease. In contrast, elevated allergen-induced Th2 cytokine responses in children related to the atopic state per se irrespective of the presence of clinical atopic disease.     

Pharmacological action of Adenophora polysaccharides

Adenophora polysaccharides (AP), is an active principle extracted from the root of Adenophorae Potaninii Korsh originated in Gansu Province and isolated with boiling water(1). AP is isolated and purified from the crude drug by DEAE-cellulose and Sephadex G-200 column, with a white powder and mean molecular weight of 8.3 × 104 , and [α]D20of AP is 68(1). AP is only composed of glucose judging from the analysis of it with patina chromatography (PC) and gas chromatography-mass spectrometer (GC-MS) methods.The methylation analysis showed that AP is composed of (1→6) linked glucose residues. The measure of nuclear magnetic resonance imaging (NMR) 1H NMR and 14C NMR techniques further proved that AP is α(l→6) linked by Dglucose. The structure of AP is as follows: -[→6]α-D-Glu(1-)n→ (2).