Systemic and Eosinophilic Lesions in Rats with Spontaneous Eosinophilia (mes Rats)

The mes rat is from an inbred mutant colony of rats with spontaneous eosinophilia. In order to investigate the pathogenesis of the mes rat, the histopathology and hematology for 76 mes rats were examined at several weeks of age. Tissue eosinophilia developed at 8 weeks of age when the blood eosinophil was 500 cells per microliter or more. Subsequently, eosinophilia progressed with age, and splenic eosinophilopoiesis and erythropoiesis appeared simultaneously. Many inflammatory lesions were induced after 10 weeks of age when the blood eosinophils became 1,000 cells per microliter or more. Gastroenteritis and mesenteric lymphadenitis were seen in 44 of 47 (94%) and 31 of 47 (66%) rats, respectively, after 10 weeks of age. Aortitis that deteriorated with age was found in 19 of 39 (49%) rats after 12 weeks of age. Hepatic fibrosis was found in four rats that exhibited severe eosinophilia and anemia. These results are comparable to the features of a hypereosinophilic syndrome in humans and other animals.

Haematological data for Matsumoto Eosinophilic Shinshu rats as determined by an automated haematology analyser

The Matsumoto Eosinophilic Shinshu (MES) rat originated from an inbred mutant colony of rats with spontaneous eosinophilia. As part of an investigation of the pathogenesis of the MES rat, we examined the haematology data for 106 males and 88 females and age-associated changes using an automated haematology analyser, flow cytometric analysis and morphological examination. The data at 10 weeks of age showed the MES rats had higher counts for eosinophils and neutrophils, slightly higher counts for lymphocytes, monocytes, basophils, and large unstained cells (LUCs), and slightly lower values for the erythrocytic parameters when compared with Sprague-Dawley (SD) rats. In data for MES rats aged 8 to 20 weeks, eosinophil counts increased with age up to 20 weeks together with some increased neutrophil counts. After 11 weeks of age, counts for lymphocytes, monocytes, basophils, and LUCs in the MES rats were also slightly increased. In female MES rats, flow cytometric analysis showed increased counts for pan-T+ cells, but blasts, abnormal granulocytes and lymphocytes were not detected morphologically. The MES rat characterized by the haematological findings could be a useful animal model for studies of hypereosinophilia.

Antihypertensive effect of nuatigenin-3-O-β-chacotriose from Solanum sisymbriifolium Lam. (Solanaceae) (ñuatî pytâ) in experimentally hypertensive (ARH+DOCA) rats under chronic administration

The aim of the study is to assess the hypotensive properties of the hydro-ethanolic crude root extract (CRE), the n-butanol fraction (F(BtOH)) and nuatigenin-3-O-β-chacotriose, from Solanum sisymbriifolium Lam., in adrenal regeneration hypertension+deoxycorticosterone acetate (ARH+DOCA) rats, following a chronic administration. The roots of S. sisymbriifolium Lam. (Solanaceae) were extracted by reflux with ethanol-water 7:3 and the active extract was fractionated by bioassay-guided liquid-liquid separation. Nuatigenin-3-O-β-chacotriose (B(3-1)) was identified as the main hypotensive compound from the crude drug by spectroscopic methods. Immature Wistar rats of both sexes were submitted to both surgery and deoxycorticosterone acetate treatment to obtain adrenal regeneration hypertensive rats (ARH+DOCA). Different groups of experimentally induced hypertensive rats were randomly allotted and received during 16 weeks a daily oral administration of 1% saline solution (0.1 mL/100g body weigh), 100.0 mg/kg of CRE, 10.0, 30.0 and 50.0 mg/kg of F(BtOH), and 1.0 mg/kg of B(3-1), respectively. In addition, two groups of ARH+DOCA rats were randomly assigned to receive either B(3-1) (1.0 mg/kg/day) or 1% of saline solution (0.1 mL/100g body weight/day) for 7 weeks and then a cross over procedure was performed in order to complete the 16th-week treatment. After 16 weeks of oral administration of crude root extract (CRE), butanolic fraction (F(BtOH)) and nuatigenin-3-O-β-chacotriose (B(3-1)) a significant reduction of blood pressure value was induced in hypertensive animals (ARH+DOCA) in comparison to the control group receiving 1% saline solution, at the end of experiment. Administration of B(3-1) (1.0 mg/kg/day p.o.) to ARH+DOCA rats provoked a significant reduction of blood pressure, observed gradually from 5th week (p<0.05) to the end of the 16th week period of treatment (p<0.01). Moreover, in a cross over design it was observed that the reduction of blood pressure to normotensive condition is associated to B(3-1). The latest demonstrated that the blood pressure-lowering effect, in clearly hypertensive animals, is reversible and depend upon administration of nuatigenin-3-O-β-chacotriose (B(3-1)). Our results demonstrated that daily oral administration of CRE, F(BtOH) and nuatigenin-3-O-β-chacotriose from S. sisymbriifolium for a 16-week period exhibits an antihypertensive effect in experimentally hypertensive (ARH+DOCA) rats.

Design of species-specific oligonucleotide probes for the detection of Bacteroides and Parabacteroides by fluorescence in situ hybridization and their application to the analysis of mouse caecal Bacteroides-Parabacteroides microbiota

AIMS

To develop species-specific monitoring techniques for rapid detection of Bacteroides and Parabacteroides inhabiting the mouse intestine by fluorescence in situ hybridization.

METHODS AND RESULTS

The specificity of oligonucleotide probes was evaluated by fluorescence whole-cell hybridization. Oligonucleotide probes specific for each species hybridized only with the target bacteria. Using these probes, caecal Bacteroides-Parabacteroides microbiota of conventional mice and specific pathogen-free (SPF) mice from three different breeders were analysed. It was shown that Bacteroides acidifaciens Group-1, Group-2 and Group-3 were dominant in conventional mice and SPF mice from two out of three breeders. Bacteroides vulgatus and Parabacteroides distasonis were detected in one of these two SPF breeding colonies in addition to Bact. acidifaciens. SPF mice of the remaining breeder harboured characteristic Bacteroides-Parabacteroides microbiota, consisting of Bacteroides sp. ASF519 and Bacteroides caccae.

CONCLUSIONS

Bacteroides acidifaciens is the dominant and most typical species in the mouse Bacteroides-Parabacteroides microbiota. The Group-3 was identified as a novel group and revealed to occupy a major niche together with Bact. acidifaciens Group-1 and Group-2.

SIGNIFICANCE AND IMPACT OF THE STUDY

The species-specific probe set developed in this study was the efficient tool for rapid detection of target bacterial groups inhabiting the mouse intestine. The results of this study provide important new information on the mouse Bacteroides-Parabacteroides community.

Is heat shock protein 60 associated with type 2 diabetes mellitus?

AIMS

HSP60 plays a protective role against heat, oxidative injury and ultraviolet. Recently, animal and clinical studies have suggested that HSP60 plays a role in various diseases. However, few epidemiological studies have demonstrated an association between HSP60 levels and type 2 diabetes mellitus. Therefore, an epidemiological study was conducted to examine the association of HSP60 with type 2 diabetes mellitus.

METHODS

This study included 83 type 2 diabetes mellitus patients and 161 controls that were recruited from male employees who received annual health check-ups between 2005 and 2007. The serum HSP60 levels were measured using the ELISA method.

RESULTS

Because the HSP60 levels were not detectable (<3.125 ng/mL) in 48.0% of the study subjects, HSP60 levels were divided into two categories (detectable or undetectable). A logistic regression analysis showed that the subjects in the undetectable had a 2.03 times higher risk of diabetes mellitus than those in the detectable after adjustment for age, BMI and rate of hypertension medication.

CONCLUSIONS

This study was the first epidemiological study to demonstrate an association between type 2 diabetes mellitus and HSP60, thus suggesting that HSP60 may play an important role in the type 2 diabetes mellitus pathology.

16S rRNA gene sequence-based analysis of clostridia related to conversion of germfree mice to the normal state

AIMS

To determine phylogenetic groups of clostridia inhabiting the mouse intestine that are essential for normalization of germfree (GF) mice.

METHODS AND RESULTS

Using both the culture method and cloning, clostridia inhabiting the mouse intestine were isolated, and phylogenetic analysis based on 16S rRNA gene sequences was carried out. As a result, the isolates were found to have novel sequences, and no isolate was determined to be identical to previously known identified clostridia. Although the taxonomy of mouse intestinal clostridia was complex, many of them belonged to Clostridium clusters XIVa and IV in conventional (CV) and limited flora mice and ex-germfree mice administered chloroform-treated CV mouse faeces. The clostridia that belonged to cluster XIVa were most often present and showed the highest diversity.

CONCLUSIONS

Clostridia belonging clusters XIVa and IV are dominant in the mouse intestine as in other gut ecosystems. The novel groups in these clusters are essential for normalization of GF mice.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of this study can be applied in the strict control of mouse intestinal microbiota and will provide important information for normalization of GF mice and also for research on microbiology of the mouse intestine.

Effects of ketamine on voltage-dependent calcium currents and membrane potentials in single bullfrog atrial cells

PURPOSE

This study was undertaken to assess the effect of ketamine on L-type calcium channel current (I(Ca)) and membrane action potential in the bullfrog single atrial myocyte.

METHODS

Bullfrog single atrial myocytes were prepared by enzymatic dispersion. Whole-cell voltage-clamp technique and current clamp technique were used to monitor I(Ca), membrane resting potential, and action potential.

RESULTS

Ketamine (10(-5)-10(-3) M) showed dose-dependent inhibition of I(Ca) in a reversible manner. The 50% inhibitory concentration (IC(50)) of ketamine on I(Ca) was estimated to be 0.92 x 10(-5) M. Use-dependent block of I(Ca) was not observed. The resting membrane potential was depolarized at a high concentration (10(-4) M) of ketamine. Reduction of the plateau phase and prolonged duration of the action potential were observed in the presence of a high concentration of ketamine (10(-4) M).

CONCLUSION

Ketamine has an inhibitory effect on I(Ca) in the bullfrog single atrial myocyte, and a high dose (10(-4) M) of ketamine prolonges the duration of the action potential. The mechanism of inhibition of I(Ca) seems to be a direct effect on the L-type calcium channel, not like an open channel blocker.

A yeast DNA microarray for the evaluation of toxicity in environmental water containing burned ash

Numerous studies on the hazard assessment and epidemiological health responses to burned ash have been reported. However, there is little information on the potential toxicity of unknown chemical complexes in burned ash. For an overall evaluation of the multiple toxicities of burned ash, a DNA microarray was used in this study, as a new attempt to assess these toxicities. Using the global gene expression on yeast DNA chip to reflect the changes in mRNA levels, our study discovered a lot of evidences for the action of cell homeostasis and stress response etc., against the toxic effects on yeast cells. On the genes of 5,117 open reading frames (ORFs), as valid spots in a microarray, 997 were up-regulated, 1,259 were down-regulated and 2,861 remained unchanged. A detailed analysis of the microarray revealed the genes that were dynamically correlated to the function of the subcellular localization, energy/metabolism, various stress responses/cell homeostasis and detoxification. Significantly, the toxicities, caused by reactive oxygen species (ROS), metals and the other xenobiotics, were indicated in burned ash. Also, the possibility of mutagenicity of the burned ash was suggested on the basis of the DNA repair related genes.

Application of artificial neural network modelling to identify severely ill patients whose aminoglycoside concentrations are likely to fall below therapeutic concentrations

OBJECTIVE

Identification of ICU patients whose concentrations are likely to fall below therapeutic concentrations using artificial neural network (ANN) modelling and individual patient physiologic data.

METHOD

Data on indicators of disease severity and some physiologic data were collected from 89 ICU patients who received arbekacin (ABK) and 61 who received amikacin (AMK). Three-layer ANN modelling and multivariate logistic regression analysis were used to predict the plasma concentrations of the aminoglycosides (ABK and AMK) in the severely ill patients.

RESULTS

Predictive performance analysis showed that the sensitivity and specificity of ANN modelling was superior to multivariate logistic regression analysis. For accurate modelling, a predictable range should be inferred from the data structure before the analysis. Restriction of the predictable region, based on the data structure, increased predictive performance.

CONCLUSION

ANN analysis was superior to multivariate logistic regression analysis in predicting which patients would have plasma concentrations lower than the minimum therapeutic concentration. To improve predictive performance, the predictable range should be inferred from the data structure before prediction. When applying ANN modelling in clinical settings, the predictive performance and predictable region should be investigated in detail to avoid the risk of harm to severely ill patients.

Massive cell death of cerebellar granule neurons accompanied with caspase-3-like protease activation and subsequent motor discoordination after intracerebroventricular injection of vincristine in mice

Vincristine, a microtubule-depolymerizing agent, is known to induce neuronal cell damage. Biochemical, histological and behavioral alterations were investigated after intracerebroventricular injection of vincristine in mice. Intracerebroventricular injection of vincristine caused caspase-3-like protease activation followed by nucleosomal release in the cerebellum. Histological examinations showed that vincristine-induced damage was relatively specific to granule cells in the cerebellum, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling-positive cells were observed among these cells. Chromatin condensation, one of the criteria for apoptosis, was seen on electron microscopy. Behavioral changes, namely head movements, pivoting and backward walking, were observed in parallel with the increase of caspase-3-like protease activity and nucleosomal release. Furthermore, motor function tests (bulb balance test and rotating rod test) showed deficits of motor coordination ability. These observations suggest that intracerebroventricular vincristine causes massive apoptosis of cerebellar granule cells accompanied with caspase-3-like protease activation, leading to motor dysfunction, in this model. These vincristine-treated mice should be a useful in vivo model for examination of neuronal apoptosis, which might be involved in a variety of neurodegenerative diseases.

The relationship of social norms to use of services and caregiver burden in Japan

PURPOSE

To develop an improved measure of "sekentei" (a social-psychological process that restricts behaviors that do not conform to social norms such as family caregiving) among family caregivers in Japan, and to describe the relationships among sekentei and caregiver's actual use of services, a reluctance to use services, and care burden.

DESIGN

Descriptive correlational study. Family caregivers (N = 260) of impaired elders responded to a structured questionnaire.

METHODS

Exploratory and confirmatory factor analyses were used to assess the construct validity of the sekentei scale for caregivers (SSC). With the SSC, the relationships among main variables were verified.

FINDINGS

The SSC showed satisfactory reliability and validity. Sekentei was significantly correlated with care burden, but not to actual use or reluctance to use services.

CONCLUSIONS

Sekentei is an important factor related to caregiver burden in Japan. Further research might include the extent to which sekentei is a factor in care burden in other cultures.

Bioassay of cadmium using a DNA microarray: genome-wide expression patterns of Saccharomyces cerevisiae response to cadmium

DNA microarray technology enables genome-wide detection of cell response at the transcriptional level. We are planning to make bioassay systems that can detect environmental chemicals to screen for potential bioreactive agents. To develop a DNA microarray for our purposes, the changes in gene expression underlying the yeast stress response to cadmium were analyzed by a microarray of total mRNA. Cadmium is a potent cell poison known to cause oxidative stress by changing intracellular glutathione levels. We report here that not only the glutathione synthesis gene (GSH1) but also almost all transcripts of the enzymes involved in the sulfur amino acid metabolism, especially MET14 and MET17, were greatly induced after exposure to cadmium. While several common stress-responsive genes, such as HSP26, GRE1, HSP12, and DDR48, were up-regulated more than almost fourfold by cadmium, there were also 42 other genes up-regulated more than fourfold. Based on these results, we concluded that DNA microarrays are very useful instruments for creating new bioassay systems and finding genetic promoters of stress indicators.

Quantitative analysis of crystalline pharmaceuticals in powders and tablets by a pattern-fitting procedure using X-ray powder diffraction data

A pattern-fitting procedure for quantitative analysis of crystalline pharmaceuticals in solid dosage forms using X-ray powder diffraction data is described. This method is based on a procedure for pattern-fitting in crystal structure refinement, and observed X-ray scattering intensities were fitted to analytical expressions including some fitting parameters, i.e. scale factor, peak positions, peak widths and degree of preferred orientation of the crystallites. All fitting parameters were optimized by the non-linear least-squares procedure. Then the weight fraction of each component was determined from the optimized scale factors. In the present study, well-crystallized binary systems, zinc oxide-zinc sulfide (ZnO-ZnS) and salicylic acid-benzoic acid (SA-BA), were used as the samples. In analysis of the ZnO-ZnS system, the weight fraction of ZnO or ZnS could be determined quantitatively in the range of 5-95% in the case of both powders and tablets. In analysis of the SA-BA systems, the weight fraction of SA or BA could be determined quantitatively in the range of 20-80% in the case of both powders and tablets. Quantitative analysis applying this pattern-fitting procedure showed better reproducibility than other X-ray methods based on the linear or integral intensities of particular diffraction peaks. Analysis using this pattern-fitting procedure also has the advantage that the preferred orientation of the crystallites in solid dosage forms can be also determined in the course of quantitative analysis.

Activation of human peroxisome proliferator-activated receptor (PPAR) subtypes by pioglitazone

Pioglitazone, a thiazolidinedione (TZD) derivative, is an antidiabetic agent that improves hyperglycaemia and hyperlipidaemia in obese and diabetic animals via a reduction in hepatic and peripheral insulin resistance. The TZDs including pioglitazone have been identified as high affinity ligands for peroxisome proliferator-activated receptor (PPAR) gamma. The selectivity of pioglitazone for the human PPAR subtypes has not been reported, thus, we investigated the effect of pioglitazone on the human PPAR subtypes. Transient transactivation assay showed that pioglitazone is a selective hPPARgamma1 activator and a weak hPPARalpha activator. Binding assay indicated that the transactivation of hPPARgamma1 or hPPARalpha by pioglitazone is due to direct binding of pioglitazone to each subtype. Furthermore, pioglitazone significantly increased the apoA-I secretion from the human hepatoma cell line HepG2.

Viability of liver slices exhibiting absorption, metabolism, and elimination of substrates in culture medium

In an attempt to improve liver slice culture for in vitro tests of newly developed drugs, we found that a relatively thick 2-mm slice was much more viable, long-lived, and metabolically functional than the conventionally used 300-microm-thick slices. Results revealed that some ionic and nonionic compounds (Na(125)I, [(14)C]Ala, and [(14)C]Xyl) dissolved in culture medium were absorbed into the slices, reaching from the cut edges deep into the inner part, in only a short period. Moreover, the slices could be observed for 24 h after incubation so that a normal histological image could be obtained. Each semi-microautoradiographic image was also clearly positive not only at the margin but also in the inner part of each slice. Furthermore, we determined the specific functioning of each donated liver for each substrate added, in uptake, metabolism, and excretion.

[Treatment of advanced Parkinson's disease]

After the advent of levodopa, treatment of Parkinson's disease has changed and the activity of daily life of patients has been remarkably improved; whereas, many patients experience various problems such as wearing-off, dyskinesia, dystonia, neuropsychiatric problems, and dysautonomia. Especially, wearing-off and dyskinesia emerge with the change of absorptional pattern of levodopa and could be solved by regulating the timing and the dose of it. Recently, some new drugs for Parkinson's disease have been available and we physician have a wide choice of them. It is important to make a careful choice of and manipulate of doses of drugs after understanding daily life of each patient enough.

Changes of secondary structure detected by laser Raman spectroscopy in model peptides of human alphaA-crystallin due to substitution of D-aspartyl residues for L-aspartyl residues

PURPOSE

We have found that two aspartyl (Asp-151 and Asp-58) residues of alphaA-crystallin are inverted and isomerized to the biologically uncommon D-beta-Asp residues during aging. In order to elucidate the correlation between the formation of the D-beta-Asp isomer and the environment surrounding the Asp in the protein, we performed a Raman spectroscopic study using two synthetic peptides: T6 peptide containing Asp-58, and T18 peptide, containing Asp-151, which correspond to the tryptic peptides of human alphaA-crystallin.

METHODS

Both T6 (Thr-Val-Leu-Asp(58)-Ser-Gly-Ile-Ser-Glu-Val-Arg) and T18 (Ile-Gln-Thr-Gly-Leu-Asp(151)-ala-thr-his-ala-Glu-Arg) peptides were synthesized with four optical isomers which have L-alpha-, D-alpha, L-beta and D-beta-aspartyl residues. These peptides were subjected to Raman measurement.

RESULTS

The Raman spectrum of the L-alpha-Asp T18 peptide measured as dry powder revealed that the secondary structure of this peptide is mainly anti-parallel beta-sheet. The main structure of the D-beta-Asp T18 peptide when in dry powder form was altered to an alpha-helix and/or random structure. The main structure of L-alpha-Asp T18 peptide when measured in aqueous solution also converted to an alpha-helix and/or random structure. The conversion of L-alpha-to D-beta-Asp in T6 peptides when in dry powder form revealed no alteration of secondary beta-sheeted structure.

CONCLUSION

Raman spectroscopy clearly revealed a large conformational change in the secondary structure of T18 peptide caused by substitution of normal L-alpha-Asp to biologically uncommon Asp-isomers. This result indicates that the inversion of an amino acid in a protein greatly affects the secondary structure of the protein.

Comparison of mortality between respondents and non-respondents in a mail survey

We conducted a population-based mail survey and prospectively compared mortality between respondents and non-respondents. Age-adjusted mortality rates for all causes were higher among non-respondents than among respondents in both sexes. Age-adjusted rate ratios were 1.50 for males and 1.33 for females. Non-respondents also had, in both sexes, higher mortality for three leading causes of death, namely, cancer, heart diseases and stroke than respondents. In particular, the difference between the two groups was much greater for cardiovascular disease than for cancer. Our results suggested that prospective studies using data from respondents to mail surveys in Japan would have underestimated the mortality for cardiovascular disease.

Physicochemical properties of amorphous precipitates of cimetidine-indomethacin binary system

We have found that the binary system, consisting of a precipitate of cimetidine and naproxen, became amorphous due to intermolecular interaction. In order to clarify the interaction between cimetidine and other drugs, the physicochemical properties of binary systems consisting of cimetidine and drugs, phenacetin, salicylamide or indomethacin, were investigated. X-ray powder diffraction patterns and thermal analysis findings for the precipitates indicated that the cimetidine-indomethacin system has an amorphous structure, whereas the cimetidine-phenacetin and cimetidine-salicylamide systems do not. Fourier-transform infra-red (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy findings suggested that there is an intermolecular interaction between a proton in the imidazole ring of cimetidine and the C=O in the COOH of indomethacin. Since an interaction by the hydrogen bond between cimetidine and indomethacin would prevent three-dimensional arrangements of the molecules, the precipitate would be amorphous. In the cimetidine-indomethacin system, decarboxylation of indomethacin occurred below the melting temperature, indicating that the chemical stability decreased upon precipitation. Cimetidine was found to interact with drugs with a carboxyl group. The interaction would be applicable to make the amorphous system of the drugs and increase the solubility of the drugs.

Hypotensive action of Nangapiry, a Paraguayan natural medicine, in rodents

Hypotensive action mechanism of a cation exchange resin adsorbate (IR-120A) separated from a Paraguayan Natural Medicine, Nangapiry, was investigated. Blood pressures of normal and pithed rats and contractions of isolated thoracic aorta and atria of mice were measured. The blood pressure on normal rats was reduced by an intravenous injection of IR-120A (5 mg/kg). The hypotensive effect on the pithed rat appeared more lasting than that on normal rats by IR-120A. The IR-120A (100 microg-3 mg/ml) concentration-dependently depressed prostaglandin (PG) F2alpha (10 microM)- or KCl (40 mM)-induced aortic contractions and electrically-evoked contraction of left atria, and at a lesser extent spontaneous beating rate of right atria. The 50% inhibitory concentrations (IC50) for the PGF2alpha- and KCl-induced aortic contractions were 713 and 828 microg/ml, respectively, and the IC50 values for the muscle contraction and the beating rate were 1.04 and >3 mg/ml, respectively. These results suggest that the hypotensive action of IR-120A are peripherally elicited by the dilatation of artery and the depression of heart contraction, but not the reduction of heart rate.

Localization of biologically uncommon D-beta-aspartate-containing alphaA-crystallin in human eye lens

PURPOSE

Previous studies demonstrated that the Asp-151 residue of alphaA-crystallin from human eye lens is stereoinverted to the biologically uncommon D-isomer and isomerized to the beta-aspartyl residue (isoaspartate) with age. To detect the locality of the D-beta-Asp-containing peptide in aged human lens, we prepared a highly specific antibody against peptide Gly-Leu-D-beta-Asp-Ala-Thr which corresponds to positions 149-153 of human alphaA-crystallin using peptide Gly-Leu-D-beta-Asp-Ala-Thr-Gly-Leu-D-beta-Asp-Ala-Thr-Gly-Leu-D-beta- Asp-Ala-Thr (designated peptide 3R) as an immunogen.

METHODS

Peptide 3R was synthesized with F-moc (9-fluorenylmethoxycarbonyl) solid phase chemistry and then the peptide was immunized in rabbits to generate antibody against peptide 3R. The antibody in rabbit serum was purified by affinity chromatography using peptide 3R and bovine alphaA-crystallin as ligands. The specificity and titer of antibody were checked by ELISA assay. We synthesized four kinds of peptide T18 (IQTGLDATHAER; corresponding to the amino acid sequences 146-157 in human alphaA-crystallin) in which Asp-151 residues were normal L-alpha-Asp, abnormal D-alpha-Asp, L-beta-Asp, and D-beta-Asp, respectively. The specificity of antibody was confirmed by ELISA using these peptides and utilized in immunohistochemistry.

RESULTS

The antibody we prepared crossreacted specifically to D-beta-Asp-151-containing alphaA-crystallin. Immunohistochemical staining of human lens with the antibody demonstrated that D-beta-Asp-151-containing alphaA-crystallin was predominantly localized in the core of aged human lens.

CONCLUSIONS

The peptide 3R antibody clearly recognized the presence of racemized and isomerized Asp-151 in both protein solution and lens tissue obtained from aged human lens.

Analysis of mean disintegration time and mean dissolution time by moment analysis using microcalorimetric curves

The mean disintegration time (MDGT; mean time required for disintegration of tablets) and mean dissolution time (MDST; mean time required for drug dissolution) of water-soluble drugs from solid dosage forms were determined by moment analysis using microcalorimetric curves. Microcalorimetric curves for heat of dilution and for heat of dissolution of the drug were prepared, and the zeroth and first moments of the calorimetric curves were then calculated. The difference between the first moments of the curves for powder dissolution and tablet dissolution was taken to be the MDGT. The difference between the first moment of the curve for heat of dilution and that of the curve for heat of dissolution was taken to be the MDST. Nicotinic acid and D-mannitol were used as model drugs. The dissolution rate was determined by the conventional beaker method and also by the deconvolution method. The dissolution process could be traced well by moment analysis, as well as by the other methods employed. Moment analysis has some advantages: (a) both the MDGT and the MDST can be determined simultaneously; (b) it is applicable to many drugs that are soluble with heat evolution without the need for quantitative analysis of the drug.

a-glucosidase Inhibitors From Paraguayan Natural Medicine, Ñangapiry, The Leaves Of Eugenia Uniflora

The water-soluble extract from a Paraguayan natural medicine, Nangapiry, the leaves of Eugenia uniflora L. (Myrtaceae), which has been used as an antidiabetic agent, was found to show inhibitory activities on the increase of plasma glucose level in the sucrose tolerance test (STT) conducted with mice. The portion adsorbed on a cation exchange resin was also found to inhibit a-glucosidases. From the active portion, two new active compounds named uniflorines A ( 1 ) and B ( 2 ) and known (+)-(3a, 4a, 5ß)-1-methylpiperidine-3, 4, 5-triol ( 3 ) were isolated. The structures of uniflorines A and B were determined as (-)-(1S, 2R, 6S, 7R, 8R, 8aR)-1,2,6,7,8-pentahydroxyindolizidine and (+)-(1S, 2R, 5R, 7R, 8S, 8aS)-1,2,5,7,8-pentahydroxyindolizidine by spectral means, respectively.

Effect of polaprezinc on healing of acetic acid-induced stomatitis in hamsters

PURPOSE

The purpose of this work was to investigate the potential effectiveness of polaprezinc in the treatment of stomatitis. Its effect on oral mucous membrane lesions was studied focusing on acetic acid-induced stomatitis in an animal model.

METHOD

Stomatitis was induced in hamsters by local injection of 30 microL of 10% acetic acid solution into both cheek pouches. Change of the size of the acetic acid-induced white lesion caused by polaprezinc injection was compared with that of control (water injection). The process of healing of damaged membrane was also investigated histopathologically. Selective adhesion of polaprezinc on mucous membrane was studied using color development by complexation between zinc and dithizone.

RESULTS

On day 4 after acetic acid injection, round white lesions were observed in the central area of both pouches. Observation on days 7, 10, and 14 showed that the size of the lesions decreased with time. Comparison with the control group of animals, in which healing took place naturally, showed that daily administration of polaprezinc (10 mg/kg) applied to the cheek pouches significantly promoted healing of the lesion from day 7 onward. Histopathological investigation of the mucous membrane in the cheek pouches 7 days after the induction of stomatitis by acetic acid injection showed thickening, and cell damage was evident. In the group of animals treated with polaprezinc, the thickening of the mucous membrane was less than that in animals of the group receiving no treatment and regeneration of damaged tissue was observed after 6 days of polaprezinc treatment.

CONCLUSION

Polaprezinc is an effective treatment in this animal model of acetic acid-induced stomatitis. This suggests that the drug may be useful in promoting healing of stomatitis in the clinical setting. Extrapolating these to humans suggests that the drug has healing effect to severe stomatitis induced by anticancer drug therapy.

Improving effects of the extracts from Eugenia uniflora on hyperglycemia and hypertriglyceridemia in mice

EtOH (70%) extracts from the leaves of Eugenia uniflora were separated into six fractions with different polarity and molecular size, i.e. NP-1-NP-6. In an oral glucose tolerance test, NP-1 and 4 inhibited the increase in plasma glucose level. However, in an intraperitoneal glucose tolerance test, such an inhibitory effect was not seen. Thus, the effects of NP-1 and 4 were apparently due to the inhibition of glucose absorption from the intestine. In a sucrose tolerance test, all fractions inhibited the increase in plasma glucose level. In an oral corn oil tolerance test, NP-3 and 4 showed an inhibitory effect on the increase in plasma triglycerides level. On the other hand, NP-3, 4, 5 and 6 inhibited maltase and sucrase activities and all fractions except for NP-1 showed an inhibitory effect on lipase activity dose-dependently. The inhibition of the increase in plasma glucose level by NP-3, 4, 5 and 6 in the oral sucrose tolerance test and the inhibition of the increase in plasma triglycerides by NP-3 and 4 in the oral corn oil tolerance test were apparently due to the inhibition of the decomposition of carbohydrates and fats in the intestine, respectively.

Formation of four isomers at the asp-151 residue of aged human alphaA-crystallin by natural aging

Although proteins are generally composed entirely of l-amino acids, we have previously shown that Asp-151 in alphaA-crystallin from aged human lens is converted to the biologically uncommon d-isomer to a high degree. The formation of d-isomer was not simple racemization, but stereoinvertion. The reaction was also accompanied with isomerization to form beta-Asp (isoaspartate) residue simultaneously; therefore, four isomers of Asp-151, normal l-alpha-Asp and biologically uncommon l-beta-Asp, d-alpha-Asp, and d-beta-Asp, are formed in alphaA-crystallins. In the present study, we measured the ratio of the four isomers of Asp-151 in alphaA-crystallins obtained from total lens proteins of human lenses of newborn and 30-, 60-, and 80-year-olds. The isomers increased with age, and the total amount of three isomers was more than that of normal l-alpha-Asp in the alphaA-crystallin of the human lenses of the 80-year-olds. These drastic changes started at birth, with about 45% of normal l-alpha-Asp lost by 30 years. These modifications of the Asp residue likely affect the three-dimensional packing array of the lens proteins.

Effect of plasma alpha1-acid glycoprotein concentration on the accumulation of lidocaine metabolites during continuous epidural anesthesia in infants and children

OBJECTIVE

Alpha1-acid glycoprotein (AAG) is an acute-phase protein that is responsible for binding basic drugs such as lidocaine (LDC). The effect of AAG on the duration of LDC during continuous epidural anesthesia in infants and young children was investigated.

PATIENTS, MATERIALS AND METHODS

Plasma levels of LDC and its active metabolites, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), were monitored in 20 infants and children, 5 months to 6 years of age, who received continuous epidural infusion of 2.5 mg kg(-1) LDC hourly during abdominal or thoracic surgeries.

RESULTS

Plasma LDC concentrations were constant after the first hour of injection. In contrast, the concentrations of MEGX and GX increased continuously during epidural infusion in all patients. The plasma AAG concentration correlated significantly (r = 0.814, p<0.001) with the steady-state LDC level. In addition, significant inverse correlation was observed between the plasma AAG concentration and the accumulation rate of MEGX (r = 0.742, p = 0.002). The plasma AAG concentration and the accumulation rate of GX correlated weakly (r = 0.474, p = 0.035). There was no correlation between the age of the patient and the plasma AAG concentrations (r = 0.295, p = 0.206).

CONCLUSION

Our results suggest that the plasma AAG concentration is a valuable index in preventing the toxicity caused by accumulation of MEGX during continuous epidural anesthesia of LDC.

D-amino acid formation induced by a chiral field within a human lens protein during aging

We have previously shown that Asp-151 in alphaA-crystallin from aged human lens are converted to the biologically uncommon D-isomer to a high degree, showing that the formation of D-isomer was not simple racemization, but stereoinvertion. This suggests that alphaA-crystallin has a chiral reaction field which promotes the inversion of L-Asp to D-Asp residues in the native higher order structure of alphaA-crystallin itself. Here, we show that when the aged human alphaA-crystallin, enriched at Asp-151 with the D-isomer (D/L ratio of 5.7), was unfolded by heating at 70 degrees C or 6 M urea, the D-Asp-151 in the unfolded alphaA-crystallin was rapidly racemized (D/L ratio of 2.17 to 1.21). This presumably reflects a relaxation of the chiral field that was initially inducing the stereoinversion from the natural L-isomer to the D-isomer.

Decatromicins A and B, new antibiotics produced by Actinomadura sp. MK73-NF4. I. Taxonomy, isolation, physico-chemical properties and biological activities

New antibiotics designated decatromicins A and B were isolated from the culture broth of Actinomadura sp. MK73-NF4. They were purified by butyl acetate extraction, silica gel column chromatography, silica gel TLC and Sephadex LH-20 column chromatography. Decatromicins A and B inhibited growth of Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA).

Effects of propofol on contractile response and electrophysiological properties in single guinea-pig ventricular myocyte

Effects of propofol on contractile response, action potential, resting membrane potential and L-type voltage-dependent calcium channel current were examined in guinea-pig single cardiac myocyte. Propofol (10(-4) M) inhibited contractile response induced by electrical stimulation (83.6% of control, n = 5), but did not change the resting membrane potential. On the other hand, propofol reduced the overshoot of action potential (10(-4) M), and shortened the duration of action potential (10(-5) and 10(-4) M). Whole-cell voltage clamp experiment showed inhibition of L-type calcium channel current (ICa, 10(-5) M: 90.8+/-1.39, 10(-4) M: 83.4+/-1.53% of control, n = 5). In addition, propofol showed use-dependent block of ICa. It is concluded that negative inotropic effect of propofol is caused by suppression of action potential, and that inhibition of ICa plays a role in shortening of the duration of action potential.

[Orthostatic transient unresponsiveness in an elderly patient with severe cerebral arteriosclerosis under antihypertensive medication]

An 80-year-old man who had was administered antihypertensive medication showed repeated transient unresponsiveness during standing and/or walking. Neurological examination showed no focal neurological signs except mild dementia. Head-up tilting examination induced unresponsiveness and a decrease of systolic blood pressure from 111 mmHg to 86 mmHg. This unresponsiveness disappeared 3 minutes later when the blood pressure recovered to 102/64 mmHg. Cerebral angiography demonstrated occlusion in the right internal carotid artery and the right vertebral artery. Severe stenosis was observed at the left internal carotid artery and the left vertebral artery. Discontinuance of the antihypertensive medication reduced the frequency of orthostatic transient unresponsiveness. Elastic stockings in the lower extremities completely prevented the attack; head-up tilting did not induce hypotension with elastic stockings. The transient unresponsiveness in the present case was probably correlated to hemodynamic failure under the condition of severe cerebral arteriosclerosis.

[Serum leptin level among non-obese students: relationship to body fat, blood pressure, serum lipids, physical activity, and eating habits]

Leptin, a product of the ob gene, is thought to play a key role in the regulation of adiposity. However, it is unclear in humans as to whether or not leptin influences the blood pressure, serum lipids, physical activity level, or eating behavior in relation to obesity. Recent reports have indicated both gender-based differences in the leptin levels and a correlation of the percentage of body fat with leptin levels has been observed among obese subjects. As far as we know, these relationships among non-obese young adults have yet to be studied. Therefore, the serum leptin concentrations among 107 non-obese students (72 males and 35 females) were measured by a radioimmunoassay(RIA). Fasting leptin levels ranging between 1.2 and 23.4 ng/mL were observed in all subjects, and the levels among females were 2.6 times higher than in males (7.64 vs 2.95 ng/mL; p < 0.001). A close correlation was observed regarding the log-transformed leptin levels with the percentage of body fat as determined by the bioelectrical impedance analysis method(r = 0.734, p < 0.001 in males and r = 0.579, p < 0.001 in females). In conclusion, these data thus suggest the serum leptin levels among non-obese students show significant gender-based differences while, in addition, the leptin levels also correlate positively with the percentage of body fat. However, it remains unclear as to whether or not the leptin levels are independently related to the blood pressure, serum lipids, physical activity level (sports activity and leisure-time activity), and eating behavior (eating breakfast, mid-day snacking and nighttime snacking).

The mechanisms of simultaneous stereoinversion, racemization, and isomerization at specific aspartyl residues of aged lens proteins

Proteins have been considered to consist exclusively of L-amino acids in living tissues. However, we found biologically uncommon D-aspartyl (Asp) residues at specific sites in alphaA- and alphaB-crystallin from the aged human lens (mean age: 80 years). In alphaB-crystallin, the Asp-36 and Asp-62 residues are highly racemized (D/L ratios: 0.92 for Asp-36; 0.54 for Asp-62). More interestingly, the configuration of the Asp-58 and Asp-151 residues in alphaA-crystallin is inverted to the D-isomer (D/L ratio: 3.1 for Asp-58, 5.7 for Asp-151). A D/L ratio > 1.0 is not considered to be due to racemization, but rather is thought to result from stereoconfiguration inversion. Our report was the first observation that inversion occurred in the configuration of amino acids in vivo during the natural aging process. We also found that these enantiomers were simultaneously isomerized to form beta-Asp residues. We propose that the mechanism of D- and beta-Asp formation in the protein depends on the primary structure and the presence of a chiral reaction field, which induces formation of D-Asp.

Serum leptin levels and their association with several factors related to arteriosclerosis among medical students in Japan

The association between serum leptin levels and several factors related to arteriosclerosis were studied in subjects who were Japanese medical students taking no medications. The group was comprised of 75 males and 35 females. The age distribution in males was 21.4 to 29.8 years (median age, 24.0 years) and in females was 21.3 to 29.9 years (median age, 22.9 years). Statistical analyses were performed using the Wilcoxon rank sum test and Spearman correlation. Median levels of serum leptin were 3.3 ng/ml in males and 7.6 ng/ml in females. The largest correlation observed was widi percent body fat irrespective of sex [males; r=0.775, p<0.001, females; r=0.553, p<0.001]. However, body mass index (BMI) was similarly well correlated with serum leptin [r=0.631, p<0.001] in males but not in females [r=0.305, p=0.075]. A negative correlation was observed between high density lipoprotein cholesterol (HDL-C) and leptin in both sexes [males; r=-0.298, p<0.01, females; r=-0.363, p<0.05] .respectively. Percent body fat, BMI, diastolic blood pressure, apolipoprotein B, and HDL-C were the most significant factors in males. Percentage of body fat and HDL-C were the most important factors in females.

Biodistribution and kinetics of holmium-166-chitosan complex (DW-166HC) in rats and mice

The fate of 166Ho-chitosan complex, a radiopharmaceutical drug for cancer therapy, was determined by studying its absorption, distribution and excretion in rats and mice.

METHODS

Holmium-166-chitosan complex [0.75 mg of Ho(NO3)3 x 5H2O and 1 mg chitosan/ head] was administered intrahepatically to male rats. Radioactive concentrations in blood, urinary and fecal excretion and radioactive distribution in tissues were examined. To determine the effects of chitosan in 166Ho-chitosan complex, 166Ho alone [0.75 mg of Ho(NO3)3 x 5H2O/head] was intrahepatically administered to male rats, and radioactive concentrations in blood, urinary and fecal excretion and radioactive distribution were examined. In B16 melanoma-transplanted nude mice, radioactive distribution after intratumoral administration of 166Ho-chitosan complex [0.075 mg of Ho(NO3)3 x 5H2O and 0.10 mg chitosan/head] was investigated also.

RESULTS

After administration of 166Ho-chitosan complex, the radioactive concentrations in blood were low, and cumulative urinary and fecal excretions over a period of 0-72 hr were 0.53% and 0.54%, respectively. The radioactive concentrations in tissues and the whole-body autoradiography images showed that most of the administered radioactivity was localized at the administration site, and only slight radioactivity was detected from the liver, spleen, lungs and bones. On the other hand, results of intrahepatic administration of 166Ho alone showed high radioactive concentrations in the blood, and the whole-body autoradiographs showed that the administered radioactivity was distributed in many organs and tissues. These results strongly suggest that 166Ho is retained at the administration site only when it forms a chelate complex with chitosan. Autoradiographs after intratumoral administration of 166Ho-chitosan complex showed that radioactivity was localized at the site of administration without distribution to the other organs and tissues.

CONCLUSION

Administered 166Ho-chitosan complex is retained at the administration site after either intrahepatic or intratumoral administration to rats or tumor-transplanted nude mice.

New medicinal treatment for severe gingivostomatitis

We formulated de novo a poraprezinc-sodium alginate suspension (P-AG) as a specific treatment for severe gingivostomatitis and administered it to 15 patients who had developed such inflammation while on chemotherapy. Very high utility of P-AG was demonstrated and the response was classified as excellent in 10 patients and good in 5 patients. The mechanism of the beneficial effect of P-AG in treatment of severe gingivostomatitis accompanied by hemorrhagic erosion and ulcers is considered to involve the mucosal protective effect, free radical scavenging activity and tissue repair promoting action of poraprezinc together with the hemostatic action of sodium alginate.

Nexilin: a novel actin filament-binding protein localized at cell-matrix adherens junction

We isolated two novel actin filament (F-actin)-binding proteins from rat brain and rat 3Y1 fibroblast. They were splicing variants, and we named brain big one b-nexilin and fibroblast small one s-nexilin. b-Nexilin purified from rat brain was a protein of 656 amino acids (aa) with a calculated molecular weight of 78,392, whereas s-nexilin, encoded by the cDNA isolated from rat 3Y1 cells by the reverse transcriptase-PCR method, was a protein of 606 aa with a calculated molecular weight of 71,942. b-Nexilin had two F-actin- binding domains (ABDs) at the NH2-terminal and middle regions, whereas s-nexilin had one ABD at the middle region because 64 aa residues were deleted and 14 aa residues were inserted in the first NH2-terminal ABD of b-nexilin, and thereby the first ABD lost its activity. b- and s-nexilins bound along the sides of F-actin, but only b-nexilin showed F-actin cross-linking activity. b-Nexilin was mainly expressed in brain and testis, whereas s-nexilin was mainly expressed in testis, spleen, and fibroblasts, such as rat 3Y1 and mouse Swiss 3T3 cells, but neither b- nor s-nexilin was detected in liver, kidney, or cultured epithelial cells. An immunofluorescence microscopic study revealed that s-nexilin was colocalized with vinculin, talin, and paxillin at cell- matrix adherens junction (AJ) and focal contacts, but not at cell-cell AJ, in 3Y1 cells. Overexpressed b- and s-nexilins were localized at focal contacts but not at cell-cell AJ. These results indicate that nexilin is a novel F-actin-binding protein localized at cell-matrix AJ.

Prediction of plasma levels of aminoglycoside antibiotic in patients with severe illness by means of an artificial neural network simulator

PURPOSE

The purpose of this work was to predict plasma peak and trough levels of an aminoglycoside antibiotic in patients with severe illness in an intensive care unit by a novel approach. Plasma levels were predicted based on the values of 15 physiological measurements using an artificial neural network (ANN) simulator.

METHOD

A data set of 15 physiological measurements for 30 patients was used to develop the model. The ANN structure consisted of three layers: an input layer comprised of 15 processing elements, a hidden layer comprised of 10 processing elements with a sigmoid function as an activation function, and an output layer of two processing elements (peak and trough levels). The weight between neurons was trained according to the delta rule back-propagation of errors algorithm. Predicted values were obtained by "leave-one-out" experiments by both ANN and multiple linear regression analysis (MLRA).

RESULTS

The correlation coefficients between observed and predicted values obtained by ANN prediction using standardized data sets were r=0.825 and r=0.854 for peak and trough levels, respectively. The correlation coefficients obtained by MLRA were r=0. 037 and r=0.276 for peak and trough levels, respectively. These results indicate that ANN shows better performance in prediction of aminoglycoside plasma levels from patients' physiological measurements than MLRA.

CONCLUSIONS

Prediction of plasma levels of antibiotic in patients with severe illness by ANN was superior to the standard statistical method. Standardization of input data was found to be important for better prediction. ANN has some advantages over standard statistical methods, as it can recognize complex relationships in the data.

Effects of thiopental on contractile and electrophysiological properties of single canine left ventricular cells

The effects of thiopental on contraction, membrane potential and membrane ionic currents were studied in single canine left ventricular cells. Thiopental 10(-5) and 10(-4) mol/l reduced the cell-shortening from 7.02 +/- 0.64 microns to 5.66 +/- 1.39 and 3.48 +/- 0.64 microns respectively (mean +/- S.D., N = 10, 0.5 Hz). This effect was enhanced in higher (> 1.0 Hz) electrical stimulation frequencies. Also, thiopental decreased the plateau phase and shortened the duration of action potential. On the other hand, voltage clamp experiment revealed that thiopental 10(-6), 10(-5), and 10(-4) mol/l reduced peak Ca2+ current from 520 +/- 48 pA to 387 +/- 60 pA, 261 +/- 84 pA, and 84 +/- 36 pA respectively (mean +/- S.D., N = 8), and showed a use-dependent block of Ca2+ current. However, only a high dose of thiopental (10(-4) mol/l) inhibited the Na+ current. We conclude that the negative inotropic effect of thiopental on the heart is mediated mainly via inhibition of the Ca2+ current.

[A prospective study on the relationship between body mass index and mortality in middle-aged and elderly people in Japan]

We conducted a prospective study to clarify the relationship between mortality and body mass index (BMI) in a middle-aged and elderly population in Japan. The subjects included 12,649 people (5,686 males and 6,963 females) aged from 40-69 years, who were identified by a mail survey between 1987 and 1989, and thereafter were followed up from the date of the survey until February 28, 1995. Cox's proportional hazards model was used to adjust for age, smoking status, drinking habit and occupation, and hazard ratios were calculated for total mortality and cancer mortality based on levels of BMI, while using a BMI of 22 to approximately 24 as a reference level. Results showed a U shaped relationship between BMI and total mortality in females. Females demonstrated a minimal total mortality in the reference group, but a significantly high hazard ratio in the lowest group of BMI < 20 (hazard ratio = 1.95, p < 0.01) and the highest group of BMI > or= 26 (hazard ratio = 1.71, p < 0.01). On the other hand, males did not demonstrate such a U shaped relationship, but instead showed an L shaped relationship between BMI and total mortality. Males showed a minimal total mortality at a BMI of 24 of approximately 26 (hazard ratio = 0.92), but a significantly high hazard ratio in the lowest BMI group (hazard ratio = 1.57, p < 0.01). In contrast, an elevated hazard ratio was not observed in the highest BMI group (hazard ratio = 1.05). The relationship between BMI and cancer mortality was found to be similar to the relationship between BMI and total mortality in both males and females. Our findings suggest that moderate overweight may be a sign of good health among both middle-aged and elderly men in Japan.

Change of the microstructure of microcrystalline cellulose with grinding and compression

The microstructure of microcrystalline cellulose was investigated by use of a radial distribution function (RDF) based on the intensity of X-ray scattering data. Changes in the microstructure of the cellulose as a result of grinding and compression were detected by use of the RDF. The RDF of intact microcrystalline cellulose had peak maxima corresponding to distances of approximately 1.5, 2.6, 5.0, 8.2, 13.3 and 17.0 A. The first two corresponded to the intramolecular atomic distances; other peaks were attributable to the intermolecular (inter-fibre) atomic distance. Changes in the RDF as a result of grinding indicated that the regular intermolecular atomic arrangement was gradually lost. Compression resulted in formation of long-range (> 20 A) ordering of the intermolecular (inter-fibre) atomic arrangement. These results show that RDF analysis is suitable for monitoring changes in the structure of microcrystalline cellulose which occur as a result of grinding and compression.

Duodenal atresia in dizygotic twins

The authors report duodenal atresia occurring in both members of dizygotic twins who showed no signs of Down's syndrome, and both had normal chromosomal constitutions. They both had the two unlinked end type of atresia in the second portion of the duodenum, and direct end-to-end duodenoduodenostomy was carried out. Their postoperative courses were smooth, and both babies were discharged 32 days after birth. Their mother underwent pituitary adenoma removal and partial parathyroidectomy for multiple endocrine neoplasia (MEN-type I). She had been given hormonal supplement therapy after surgery and became pregnant after exogenous gonadotropin therapy. Environmental factors may be responsible for some cases of duodenal atresia.

The conformation formed by the domain after alanine-155 induces inversion of aspartic acid-151 in alpha A-crystallin from aged human lenses

A new cleavage site, which is a post-translational modification, was found between residues His-154 and Ala-155 in alpha A-crystallin from the aged human lens. After trypsin digestion of alpha A-crystallin two peptides that include Asp-151 were obtained and have remarkable differences. That is, the stereo-configuration of the Asp-151 in the normal length peptide was predominately inverted to the D-isomer of beta-aspartyl form (D/L of 5.7). However, the stereoconfiguration of the Asp-151 in the cleavage peptide, that lacks the sequence following Ala-155 to the C-terminus, remained predominately in the L-isomer form as indicated by a D/L value of 0.3. The results suggest that the secondary structure in the region of Ala-155 to the C-terminus may constitute a field that causes the inversion of the Asp-151 to the D-isomer form. Since this kind of cleavage was not found in alpha A-crystallin from young lens, the cleavage between His-154 and Ala-155 is probably the result of aging.

Specific racemization and isomerization of the aspartyl residue of alphaA-crystallin due to UV-B irradiation

We have reported that the aspartyl (Asp)-151 residue in alphaA-crystallin in human eye lens was inverted to the D-isomer and isomerized to beta-Asp residue with age. We report here that ultraviolet (UV)-B irradiation induces the racemization and isomerization of the Asp-151 residue of alphaA-crystallin from lenses of 6-week-old rats to form D-isomer and beta-Asp residue. Simultaneous racemization and isomerization of the specific Asp residue indicate that the reaction proceeds via formation of a succinimide intermediate. This modification was not observed in UV-A irradiated and normal lenses. UV-B irradiation induced the racemization of only the Asp-151 residue and did not affect the other Asp residues in alphaA-crystallin. On the other hand, the high molecular weight fraction of the lens protein increased upon UV-B irradiation. Modification of the Asp residue would affect the three-dimensional packing array of the lens protein.