Characterization of idiotopes on MOPC 315 IgA using monoclonal antiidiotypic antibodies

The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG_2a), A2(IgG₁), G3 (IgG_2b) and F1 (IgG_2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H³¹⁵ L³¹⁵ and F³¹⁵_V but not with free H³¹⁵, L³¹⁵, V³¹⁵_H or V³¹⁵₂. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H³¹⁵ and L³¹⁵. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H³¹⁵ which requires an interaction with either L³¹⁵ or L⁴⁶⁰ for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.     

DNA degradation by the mixture of copper and catechol is caused by DNA-copper-hydroperoxo complexes, probably DNA-Cu(I)OOH

Free hydroxyl radicals (free (.)OH), singlet oxygen ((1)O(2)), or (. )OH produced by DNA-copper-hydroperoxo complexes are possible DNA-damaging reactive oxygen species (ROS) in the reaction system containing copper, catechol, and DNA. para-Chlorobenzoic acid (pCBA) degradation studies revealed that CuCl(2) mixed with catechol produced free (.)OH. In the presence of DNA, however, inhibition of the pCBA degradation suggested that another ROS is responsible for the DNA degradation. Of a series of ROS scavengers investigated, only KI, NaN(3), and Na-formate-all of the salts tested-strongly inhibited the DNA degradation, suggesting that the ionic strength rather than the reactivity of the individual scavengers could be responsible for the observed inhibition. The ionic strength effect was confirmed by increasing the concentration of phosphate buffer, which is a poor (.)OH scavenger, and was interpreted as the result of destabilization of DNA-copper-hydroperoxo complexes. Piperidine-labile site patterns in DNA degraded by copper and catechol showed that the mixture of Cu(II) and catechol degrades DNA via the intermediate formation of a DNA-copper-hydroperoxo complex. Replacement of guanine by 7-deazaguanine did not retard the DNA degradation, suggesting that the DNA-copper-hydroperoxo complexes do not bind to the guanine N-7 as proposed in the literature.     

Effect of age and ambient temperature on n-pentane production in adult housefly, Musca domestica

The objective of this study was to examine the relationship between lipid peroxidation and aging in the male housefly. Metabolic rate of flies is known to be higher and life span shorter at elevated ambient temperature. Evolution of n-pentane and level of thiobarbituric acid (TBA) reactive material were used as indicators of lipid peroxidation. n-Pentane accumulated by houseflies in vivo and by whole body homogenates of houseflies, in response to tert-butyl hydroperoxide (1 mM), increased with age. n-Pentane accumulation in vivo was markedly higher at higher ambient temperature. Furthermore, n-pentane generated by flies in vivo and by fly homogenates in vitro tended to be lower in flies raised at a lower ambient temperature. TBA-reactive material, elicited by tert-butyl hydroperoxide, was augmented in older flies, but no significant difference was found between flies aged at different ambient temperatures. Analysis of fatty acids in housefly homogenates indicated an age-associated increase in the ratio of polyunsaturated to saturated fatty acids.     

强心甙中毒的心肌超微结构变化和甘露醇的保护作用

ⅳ羟自由基清除剂甘露醇,1.1mol/L 2g/kg和3 g/kg可分别使哇巴因致豚鼠LD_(100)由298.54±33.30 μg/kg增高至367.44±44.58μg/kg(P<0.05)和398.49±35.39 μg/kg(P<0.01)。甘露醇略可提高哇巴因致心律失常发生的阈值,但无统计学意义。取哇巴因致心脏出现室性早搏、室性心动过速、室性纤维性颤动和心跳停止时的左室游离壁心肌,用透射电子显微镜观察心肌超微结构的改变,结果表明心肌细胞膜结构发生明显的破坏,并随中毒的加重,心肌结构的破坏亦更严重。     

A way of preventing the free fatty acid concentration in the serum of rabbits from rising

A scheme of administration of nicotinic acid by mouth is suggested in order to prevent any increase in the free fatty acid concentration in the serum after intravenous injection of heparin or triiodothyronine, prolonged starvation, and thyroid feeding.Laboratory of Pathological Physiology, Institute of Experimental Endocrinology and Hormone Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Yudaev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 8, pp. 122–125, August, 1974.     

8OHdG levels in brain do not indicate oxidative DNA damage in Alzheimer''s disease

Accumulation of oxidative DNA damage has been proposed to underlie aging and neurodegenerative diseases such as Alzheimer's Disease (AD). The DNA adduct 8-hydroxy-2′-deoxyguanosine (8OHdG) is considered a good indicator of oxidative DNA damage. To investigate whether this type of DNA damage is involved in AD etiology, 8OHdG levels were determined in postmortem human brain tissue of controls and AD patients (in frontal, occipital, and temporal cortex and in hippocampal tissue). Parametric studies in rat revealed no influences of postmortem delay, repeated freezing/thawing or storage time. In human brain, approximately two 8OHdG molecules were present per 10⁵ 2′-deoxyguanosines. In AD patients and controls, 8OHdG-levels were not related to age, sex, or brain region. Also, no differences were found between controls and AD patients. It was concluded that 8OHdG in nuclear DNA, although present throughout the brain in fairly high amounts, does not accumulate with age, nor does it appear to be involved in AD. More detailed studies are required to extend this conclusion to other types of oxidative damage.     

Narrowly Distributed Surfactant‐Free Polystyrene Latex with a Water‐Soluble Comonomer

Summary: The surfactant‐free synthesis of latex polymers of styrene and sodium styrenesulfonate (NaSS) was investigated. The development of size and size distribution of the particles was studied by photo‐correlation spectroscopy (PCS) and transmission electronic microscopy (TEM). The effects of NaSS concentration and the order of addition of reactants were examined in detail. The results showed that the particle size decreases with an increase in the styrene sulfonate concentration. The polydispersity index can be reduced by mixing NaSS with styrene homogeneously before adding initiator, but this leads to a slightly larger mean particle size.

TEM image of surfactant‐free polystyrene latex made by the modified method.     

Assessing Health-Related Quality of Life in Children with Coeliac Disease: The Italian Version of CDDUX

We aimed to assess Health-Related Quality of Life (HRQoL) of Italian children and their parents with coeliac disease (CD) using the Coeliac Disease Dutch Questionnaire (CDDUX). The CDDUX underwent a cross-cultural adaptation in a multi-step process, according to international guidelines. A total of 224 children aged between 8–18 years and their parents were prospectively recruited. Cronbach α coefficient was determined as a measure of internal consistency of the questionnaire and inter-children/parent reliability by intraclass correlation coefficient. Univariate and bivariate regression models were used to evaluate correlations between clinical variables and children and parents subclasses of CDDUX and overall mean Paediatric Quality of Life Inventory (PedsQL). The Italian CDDUX proved to be valid and reliable, mean CDDUX total score revealing a neutral evaluation of the quality of life in children 52.6 ± 17.2 and parents 49.5 ± 17.9 (p = 0.07) with strong correlation with PedsQL. The only clinical variable which appeared to affect significantly quality of life both in children and parents was the lower age. A comparison with our results showed remarkable differences in the HRQoL of populations of various nationalities. The Italian version of the CDDUX questionnaire is a simple and reliable tool for assessing the HRQoL in children and adolescents with CD.     

Free Fatty Acids Signature in Human Intestinal Disorders: Significant Association between Butyric Acid and Celiac Disease

Altered circulating levels of free fatty acids (FFAs), namely short chain fatty acids (SCFAs), medium chain fatty acids (MCFAs), and long chain fatty acids (LCFAs), are associated with metabolic, gastrointestinal, and malignant diseases. Hence, we compared the serum FFA profile of patients with celiac disease (CD), adenomatous polyposis (AP), and colorectal cancer (CRC) to healthy controls (HC). We enrolled 44 patients (19 CRC, 9 AP, 16 CD) and 16 HC. We performed a quantitative FFA evaluation with the gas chromatography–mass spectrometry method (GC–MS), and we performed Dirichlet-multinomial regression in order to highlight disease-specific FFA signature. HC showed a different composition of FFAs than CRC, AP, and CD patients. Furthermore, the partial least squares discriminant analysis (PLS-DA) confirmed perfect overlap between the CRC and AP patients and separation of HC from the diseased groups. The Dirichlet-multinomial regression identified only strong positive association between CD and butyric acid. Moreover, CD patients showed significant interactions with age, BMI, and gender. In addition, among patients with the same age and BMI, being male compared to being female implies a decrease of the CD effect on the (log) prevalence of butyric acid in FFA composition. Our data support GC–MS as a suitable method for the concurrent analysis of circulating SCFAs, MCFAs, and LCFAs in different gastrointestinal diseases. Furthermore, and notably, we suggest for the first time that butyric acid could represent a potential biomarker for CD screening.