Effects of prostaglandin E2 and D2 on gastric somatostatin and gastrin secretion

The effects of PGE2 and PGD2 on gastric somatostatin and gastrin releases were investigated using the isolated perfused rat stomach. In the presence of 5.5 mM glucose, the infusion of PGE2 elicited a significant augmentation in somatostatin release, but suppressed gastrin secretion from the perfusate. On the other hand, PGD2 did not affect somatostatin release, although the gastrin secretion decreased significantly, the same as after PGE2 infusion. These results suggest that PGE2 and PGD2 may be important in the regulation of gastric endocrine function, but that PGD2 does not affect gastric somatostatin secretion.     

Augmentation of antitumor immunity in regional lymph nodes by local immunotherapy

We have previously reported that the antitumor effect of OK-432, a streptococcal preparation, is markedly augmented when injected intratumorally together with fibrinogen (OK-432/fbg) [1]. In order to elucidate the effects of this immunotherapy on regional lymph nodes (RLN), we carried out both morphological and functional analyses of the RLN from colonic cancer patients treated with OK-432/ fbg. Computer-aided morphometry revealed that the maximal cross-sectional areas and the broadest diameters of the RLN were significantly greater (p<0.01) in patients who had undergone local immunotherapy than in patients who had not. The component structures of RLN, such as sinus, follicle and paracortex, were all enlarged in the OK-432/fbg-treated patients, and necrosis of metastatic tumors was observed. RLN lymphocytes recovered from OK-432/fbg treated patients showed elevated reactivity to phytohemagglutinin (PHA) and the stimulation index was clearly higher than that of control patients. Flow cytometric analysis revealed a predominance of T-cells, especially CD4 subsets, and higher positivity for both CD25 and HLA-DR. Furthermore, RLN lymphocytes killed more effectively K562 and Daudi cells in the patients who had had immunotherapy. These results suggest that the effect of local immunotherapy with OK-432/fbg is not restricted to the site of injection but extends to the lymph nodes, and contributes to tumor regression through the augmentation of cellular immunity.Abbreviations RLN regional lymph node(s) - OK-432/fbg OK-432/fibrinogen solution - PHA phytohemagglutinin - NK natural killer - LAK lymphocyte activated killer     

Long-term chromium picolinate supplementation improves colostrum profile of Santa Ines ewe

Biological Trace Element Research - Chromium (Cr) is a micromineral that is involved in the metabolism of carbohydrates, lipids, ammonia, and nucleic acids; thus, its supplementation can influence...     

Gender difference regarding selenium penetration into the mouse brain

A sex difference in the penetration of selenium into the brain was observed using lipopolysaccharide (LPS)-injected mice. The selenium concentration increased in the brains of sodium selenite-injected LPS-treated female mice, but not males. The selenium concentration peaked when selenite was injected 3 h after the injection of LPS into female mice. In addition, selenium in the brain increased when a dosage of 30 μmol/kg and more of selenite was injected into LPS-treated female mice. Also, the selenium concentration in the brain increased and peaked 2–3 h after selenite injection; 24 h later, the level was similar to the Se-only group. The penetration of selenium into the brain was inhibited by pretreatment with aminoguanidine, an inhibitor of nitric oxide synthetase. From the present results, selenium more easily penetrated into the brains of female mice compared to males after LPS treatment, and nitric oxide may have affected the penetration. However, the sex difference mechanism for selenium penetration needs further investigation.     

Exercise and diet enhance fat oxidation and reduce insulin resistance in older obese adults.

Older, obese, and sedentary individuals are at high risk of developing diabetes and cardiovascular disease. Exercise training improves metabolic anomalies associated with such diseases, but the effects of caloric restriction in addition to exercise in such a high-risk group are not known. Changes in body composition and metabolism during a lifestyle intervention were investigated in 23 older, obese men and women (aged 66 +/- 1 yr, body mass index 33.2 +/- 1.4 kg/m(2)) with impaired glucose tolerance. All volunteers undertook 12 wk of aerobic exercise training [5 days/wk for 60 min at 75% maximal oxygen consumption (Vo(2max))] with either normal caloric intake (eucaloric group, 1,901 +/- 277 kcal/day, n = 12) or a reduced-calorie diet (hypocaloric group, 1,307 +/- 70 kcal/day, n = 11), as dictated by nutritional counseling. Body composition (decreased fat mass; maintained fat-free mass), aerobic fitness (Vo(2max)), leptinemia, insulin sensitivity, and intramyocellular lipid accumulation (IMCL) in skeletal muscle improved in both groups (P < 0.05). Improvements in body composition, leptin, and basal fat oxidation were greater in the hypocaloric group. Following the intervention, there was a correlation between the increase in basal fat oxidation and the decrease in IMCL (r = -0.53, P = 0.04). In addition, basal fat oxidation was associated with circulating leptin after (r = 0.65, P = 0.0007) but not before the intervention (r = 0.05, P = 0.84). In conclusion, these data show that exercise training improves resting substrate oxidation and creates a metabolic milieu that appears to promote lipid utilization in skeletal muscle, thus facilitating a reversal of insulin resistance. We also demonstrate that leptin sensitivity is improved but that such a trend may rely on reducing caloric intake in addition to exercise training.     

Evaluation of a cervical cancer screening program based on HPV testing and LLETZ excision in a low resource setting

We conducted studies in Vanuatu to evaluate potential screening and treatment strategies to assist with control of cervical cancer. In a pilot study of 496 women, visual inspection and cytology were evaluated as screening tests for detection of CIN 2 or worse (CIN2+), observed in 21 of 206 subjects biopsied on the basis of abnormal visual inspection or cytology. Sensitivity of visual inspection with Lugol's Iodine for detection of CIN2+ on biopsy was 0.63, specificity was 0.32, and the positive predictive value was 0.09. For HSIL cytology, sensitivity was 0.99, specificity was 0.77, and the positive predictive value was 0.88. HSIL cytology was significantly more sensitive and had a significantly higher PPV for CIN 2+ than visual inspection (p<0.01). In a further study of 514 women, we compared testing for HR HPV and cytology as predictors of biopsy proven CIN 2+. Sensitivity of HSIL cytology for CIN2+ as established by loop excision of the cervix was 0.81, specificity was 0.94, and positive predictive value was 0.48. Sensitivity of a positive test for HR HPV for detection of CIN2+ was non-significantly different from cytology at 0.81, specificity was 0.94, and positive predictive value was 0.42. Combining the two tests gave a significantly lower sensitivity of 0.63, a specificity of 0.98, and a positive predictive value of 0.68. For women over 30 in a low resource setting without access to cytology, a single locally conducted test for high risk HPV with effective intervention could reduce cervical cancer risk as effectively as intervention based on cytology conducted in an accredited laboratory.     

Lack of involvement of metallothionein expression in pancreatic carcinogenesis by N-nitrosobis (2-oxopropyl) amine in Syrian hamsters.

The possible involvement of metallothionein (MT) in pancreatic ductal carcinogenesis by N-nitrosobis(2-oxopropyl) amine (BOP) in hamsters was investigated. Hamsters received subcutaneous (s.c.) injections with dissolved BOP to 70 mg/kg body weight (BW) followed 7 days later by 20 mg/kg BW BOP and they were sacrificed at 4, 11, 16 and 27 weeks after the beginning of the experiment. MT expression was studied by immunohistochemistry and MT contents were assayed biochemically. Pancreatic ductal hyperplasias were developed from 11 weeks on and carcinomas from 16 weeks on, the incidence of the latter reaching 73% at the end of experiment. However, while normal appearing proliferating duct cells were sometimes positive, MT expression was not evident in hyperplasia (H), atypical hyperplasia (AH) or carcinoma (C), and MT contents did not significantly differ in pancreas of hamsters receiving saline or BOP at any time point. The results suggest that MT is not involved in pancreatic duct carcinogenesis. However, the presence of MT in proliferating ducts not related to carcinogenesis may suggest some unknown role for MT in cellular homeostasis.     

A comparative study of monosaccharide composition analysis as a carbohydrate test for biopharmaceuticals

The various monosaccharide composition analysis methods were evaluated as monosaccharide test for glycoprotein-based pharmaceuticals. Neutral and amino sugars were released by hydrolysis with 4–7 N trifluoroacetic acid. The monosaccharides were N-acetylated if necessary, and analyzed by high-performance liquid chromatography (HPLC) with fluorometric or UV detection after derivatization with 2-aminopyridine, ethyl 4-aminobenzoate, 2-aminobenzoic acid or 1-phenyl-3-methyl-5-pyrazolone, or high pH anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Sialic acids were released by mild acid hydrolysis or sialidase digestion, and analyzed by HPLC with fluorometric detection after derivatization with 1,2-diamino-4,5-methylenedioxybenzene, or HPAEC-PAD. These methods were verified for resolution, linearity, repeatability, and accuracy using a monosaccharide standard solution, a mixture of epoetin alfa and beta, and alteplase as models. It was confirmed that those methods were useful for ensuring the consistency of glycosylation. It is considered essential that the analytical conditions including desalting, selection of internal standards, release of monosaccharides, and gradient time course should be determined carefully to eliminate interference of sample matrix.Various HPLC-based monosaccharide analysis methods were evaluated as a carbohydrate test for glycoprotein pharmaceuticals by an inter-laboratory study.     

A possible physiological function and the tertiary structure of a 4-kDa peptide in legumes.

Previously, we isolated a 4-kDa peptide capable of binding to a 43-kDa receptor-like protein and stimulating protein kinase activity of the 43-kDa protein in soybean. Both of them were found to localize in the plasma membranes and cell walls. Here, we report the physiological effects of 4-kDa peptide expressed transiently in the cultured carrot and bird's-foot trefoil cells transfected with pBI 121 plasmid containing the 4-kDa peptide gene. At early developmental stage, the transgenic callus grew rapidly compared to the wild callus in both species. Cell proliferation of in vitro cultured nonembryogenic carrot callus was apparently affected with the 4-kDa peptide in the medium. Complementary DNAs encoding the 4-kDa peptide from mung bean and azuki bean were cloned by PCR and sequenced. The amino-acid sequences deduced from the nucleotide sequences are homologous among legume species, particularly, the sites of cysteine residues are highly conserved. This conserved sequence reflects the importance of intradisulfide bonds required for the 4-kDa peptide to perform its function. Three dimensional structure of the 4-kDa peptide determined by NMR spectroscopy suggests that this peptide is a T-knot scaffold containing three beta-strands, and the specific binding activity to the 43-kDa protein and stimulatory effect on the protein phosphorylation could be attributed to the spatial arrangements of hydrophobic residues at the solvent-exposed surface of two-stranded beta-sheet of 4-kDa peptide. The importance of these residues for the 4-kDa peptide to bind to the 43-kDa protein was indicated by site-directed mutagenesis. These results suggest that the 4-kDa peptide is a hormone-like peptide and the 43-kDa protein is involved in cellular signal transduction of the peptide.     

Identification of metallothionein isoforms on capillary zone electrophoresis by adding anti-metallothionein antibody

The aim of this study was to identify metallothionein (MT) isoforms in mouse liver by using capillary zone electrophoresis (CZE). Purified MT-1 and MT-2 isoforms were completely separated by CZE using a polyacrylamide-coated tube at physiologic pH. There were two peaks in the cytosol fraction prepared from zinc-injected mouse liver, in which the migration times corresponded with those of purified MT-1 and MT-2 isoforms. When anti-MT monoclonal antibody was added with the purified MT-1 or MT-2 solution, the peaks decreased. Furthermore, the two peaks in the cytosol prepared from Zn-injected mouse liver decreased in a time-dependent manner from the electropherogram after the addition of the antibody. Therefore, those peaks were identified as MT-1 and MT-2 isoforms, respectively. In conclusion, the addition of anti-MT monoclonal antibody to the cytosol fraction of tissues is an effective method for identification of MT isoforms after separation using CZE.