Acute biochemical variations induced by calcium citrate and calcium carbonate in Type 2 diabetic patients: impaired calcium absorption in Type 2 diabetic patients with prolonged gastric emptying time

Calcium supplementation is important in the treatment of osteoporosis, a disease that may also occur in diabetic patients. The acute effects of calcium supplementation and their relationship to gastric emptying time, however, have rarely been studied in type 2 diabetic patients. We evaluated the acute biochemical variations induced by the administration of two different calcium preparations, calcium citrate and calcium carbonate, in 16 (male/female: 13/3) Chinese diabetic patients. Serum free calcium, intact parathyroid hormone (i-PTH), and amount of urinary excretion of calcium (uCal/uCr) were evaluated after a single dose of 1200 mg of elemental calcium in each preparation. The free calcium levels did not change significantly in either group. However, significant suppression of i-PTH after calcium citrate administration at 1 h (17.1+/-2.0 pg/ml, P=.023), and after calcium carbonate administration at 2 h (14.2+/-2.5 pg/ml, P=.000), was noted when compared with individual basal level (21.2+/-2.5 and 19.3+/-2.4 pg/ml, respectively). The suppressive effect on i-PTH lasted for 6 h after calcium citrate and 5 h after calcium carbonate preparation of the 6-h study period. After administration of calcium citrate, the uCal/uCr of 2-to-4-h collection was significantly higher than that of the basal and 0-to-2-h collections: 0.25+/-0.04 vs. 0.19+/-0.03, P=.025; and 0.25+/-0.04 vs. 0.19+/-0.02, P=.014, respectively. A similar finding was observed for calcium carbonate: 0.23+/-0.03 vs. 0.18+/-0.02, P=.019; and 0.23+/-0.03 vs. 0.18+/-0.02, P=.011, respectively. We conclude that, in this group of Chinese type 2 diabetic patients in our study, the oral administration of 1200 mg elemental calcium in either calcium citrate or calcium carbonate preparation can induce a significant suppression of i-PTH. This may be helpful in preventing or treating osteoporosis. A prolonged gastric emptying time in these diabetic subjects may contribute to the non-significant alteration in free calcium levels after the administration of either calcium preparation.

ATP-induced mucin release from cultured airway goblet cell involves, in part, activation of phospholipase A2

Adenosine triphosphate (ATP) has been shown to stimulate mucin release by activation of protein kinase C (PKC) following activation of phospholipase C (PLC) coupled to the P2 receptor via G-proteins. The aim of the present study was to investigate pathways downstream to the PKC activation in ATP-induced mucin release from primary hamster tracheal surface epithelial (HTSE) cells. The release of mucin was determined by chromatographic procedure after metabolic labeling of mucin with [3H]-glucosamine. The results were: i) ATP induced the release of arachidonic acid, which caused the release of mucin. Pretreatment with mepacrine (0.3 mM), a phospholipase A2 (PLA2) inhibitor, inhibited the ATP-induced arachidonic acid and mucin release. Oleoyloxyethylphosphocholine, another PLA2 inhibitor, gave similar results. ii) An activator of PKC, 4 beta-phorbol-12 alpha-myristate-13-acetate (PMA, 1 microM) induced mucin release, which was inhibited by mepacrine pretreatment. iii) Downregulation of PKC by prolonged (16 h) PMA treatment caused inhibition of ATP-induced mucin release. Treatment of PKC downregulated HTSE cells with mepacrine did not further decrease the ATP-induced mucin release. These results suggest that PLA2 is involved in ATP-induced mucin release and its activation is sequential to the PLC-PKC pathway.

Simvastatin treatment on postprandial hypertriglyceridemia in type 2 diabetes mellitus patients with combined hyperlipidemia

Recent studies have shown that statins are effective in reducing fasting low-density lipoprotein-cholesterol (LDL-C) and triglyceride levels. However, it remains unknown if treatment with statins also lowers daily postprandial triglyceride concentrations, which may promote atherogenesis in type 2 diabetes subjects. Forty-one subjects with type 2 diabetes and combined hyperlipidemia who had stable glycemic control were randomly assigned to take simvastatin 20 mg (n = 27) or a placebo (n = 14) once daily for 12 weeks. The medication dosage was doubled after 4 weeks if a subject's LDL-C was not less than 130 mg/dL. Among these participants, 24 subjects (15 on simvastatin and 9 on placebo) agreed to take a meal tolerance test with isocaloric mixed meals (carbohydrate, 52%; fat, 33%, and protein, 15% of the daily caloric intake) and daytime hourly blood sampling from 8 AM to 4 PM. Simvastatin treatment reduced the fasting total cholesterol level from 237 +/- 5 to 178 +/- 6 mg/dL (-25%), the LDL cholesterol level from 150 +/- 6 to 87 +/- 5 mg/dL (-40%), and raised high-density lipoprotein-cholesterol (HDL-C) level from 36 +/- 2 to 40 +/- 2 mg/dL (+11%) (all P <.001). Fasting and daily ambient triglyceride concentrations from 8 AM to 4 PM decreased significantly in response to simvastatin administration (P <.001), but not to the placebo (P =.305). Simvastatin treatment not only decreased total cholesterol and LDL-C levels and increased HDL-C levels effectively, it also decreased fasting, as well as daily postprandial triglyceride concentrations, but had no effect on glycemic control in type 2 diabetes subjects with combined hyperlipidemia.

Laparoscopic versus open vertical banded gastroplasty for the treatment of morbid obesity

Vertical banded gastroplasty (VBG) is an effective treatment for morbid obesity. Recent advancement in laparoscopic surgery has made laparoscopic VBG possible. The authors compared retrospectively the outcomes of laparoscopic VBG versus open VBG in patients with morbid obesity. From June 1998 to April 1999, 100 patients (18 men, 82 women; average age, 32.6 years) underwent laparoscopic VBG, and 40 patients (7 men, 33 women; average age, 28.8 years) underwent conventional open VBG. The two groups were similar regarding sex, age, and body mass index distribution. Mean surgical time, blood loss estimate, duration of postoperative recovery, analgesic usage, complications, and weight reduction were compared among the two groups. Laparoscopic VBG was successful in 99 (99%) of the 100 patients. Mean surgical time was longer in duration for the laparoscopic VBG group than it was for the open VBG group (173 vs. 101 minutes, P < 0.01). The laparoscopic VBG group had earlier flatus passage (1.9 vs. 2.6 days; P < 0.01), less usage of analgesics (meperidine 50 mg/unit; 0.9 vs. 2.3 units; P < 0.01), and a shorter postoperative hospital stay (3.7 vs. 6.0 days; P < 0.01). Estimated blood loss, surgical complication rate, and weight reduction were similar among the two groups. Although laparoscopic VBG required a longer surgical time and was technically more demanding, it resulted in shorter recovery time, less analgesic use, and less severe physical discomfort. The authors' findings show that the two methods were approached safely equally.

Decomposition of ethylene oxide in the RF plasma environment

A radio frequency (RF) plasma system was used to decompose the ethylene oxide (EO) contained gas in the EO/Ar, and EO/O2/Ar system, respectively. The reactants and final products were analyzed by using FTIR (Fourier transform infrared spectroscopy). The effects of plasma operational parameters, including input power wattage (W), total gas flow rate (Q), feeding concentration (C) of EO and operational pressure for EO decomposition were evaluated. Due to the importance of the high-energy electrons in the RF plasma system, the EO decomposition fraction in plasma reaction increased with decreasing operational pressure, while that of thermal reaction, reported by previous investigations, increased with increasing operational pressure. However, owing to the electrophilic characteristic of oxygen atoms in the EO molecule causing the effect of electron attachment, in conditions of higher EO feeding concentration, the pressure dependence became the same for both plasma- and thermal-reaction. The EO oxidation reaction has also been investigated, the result shows that EO almost completely oxidized at 600-692 K gas temperature. The main products for the EO/Ar system are CO, CH4, C2H6, C2H4, and C2H2, and those for the EO/O2/Ar system are CO2 and H2O.

Detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic liver: accuracy of ultrasonography in transplant patients

The purpose of this study was to assess the usefulness of ultrasonography in the detection of hepatocellular carcinomas and dysplastic nodules in patients with liver cirrhosis. Pretransplantation sonograms in 52 patients with liver cirrhosis who underwent orthotopic liver transplantation were evaluated retrospectively. The numbers of hepatocellular carcinomas and dysplastic nodules were assessed in the explanted liver specimens and compared with pretransplantation ultrasonographic results. Eighteen hepatocellular carcinomas in 16 patients and 20 dysplastic nodules in 11 patients were present in the explanted livers. The size of hepatocellular carcinomas ranged from 0.6 to 5.0 cm (mean, 2.1 cm) in diameter, and that of dysplastic nodules ranged from 0.5 to 1.7 cm (mean, 1.0 cm) in diameter. Pretransplantation ultrasonography enabled detection of 6 of 18 hepatocellular carcinoma and 0 of 20 dysplastic nodule lesions; lesion detection sensitivity for hepatocellular carcinomas and dysplastic nodules was 33% and 0%, respectively. Patient sensitivity and specificity for hepatocellular carcinomas were 38% (6 of 16) and 92% (33 of 36), and those for dysplastic nodules were 0% and 95% (39 of 41), respectively. On the basis of our results, ultrasonography is insensitive for detection of hepatocellular carcinomas and dysplastic nodules in patients with advanced liver cirrhosis.

Effect of fuel aromatic content on PAH emission from a heavy-duty diesel engine

Polycyclic aromatic hydrocarbons (PAHs) emission tests for a heavy-duty diesel engine fueled with blend base diesel fuel by adding batch fractions of poly-aromatic and mono-aromatic hydrocarbons, Fluorene and Toluene, respectively, were simulated to five steady-state modes by a DC-current dynamometer with fully automatic control system. The main objective of this study is to investigate the effect of total aromatic content and poly-aromatic content in diesel fuels on PAH emission from the HDD engine exhaust under these steady-state modes. The results of this study revealed that adding 3% and 5% (fuel vol%) Fluorene in the diesel fuel increases the amount of total-PAH emission by 2.6 and 5.7 times, respectively and increases the amount of Fluorene emission by 52.9 and 152 times, respectively, than no additives. However, there was no significant variation of PAH emission by adding 10% (vol%) of Toluene. To regulate the content of poly-aromatic content in diesel fuel, in contrast to the total aromatic content, will be more suitable for the management of PAH emission.

High-level expression of antimicrobial peptide mediated by a fusion partner reinforcing formation of inclusion bodies

A gene expression system for antimicrobial peptides, which could be effectively used for various studies or applications of the antimicrobial peptides, has been developed. To avoid the harmful effects on an expression host, Escherichia coli, the antimicrobial peptides were expressed as fusion proteins with a polypeptide F4, which is a truncated PurF fragment that highly tends to form inclusion bodies. Seven different kinds of antimicrobial peptides have been successfully expressed by this expression system and the resulting expression level of fusion proteins reached up to 30% of total cell proteins. To confirm the identity of the recombinant peptide, MSI-344 was selected as a model peptide and purified to homogeneity, and we could obtain the recombinant MSI-344 of a high purity and with a good yield, which was identical to the authentic peptide in the aspects of the chemical and antimicrobial properties. These results show that the neutral fusion partner, which reinforces the formation of inclusion bodies, could mediate a high-level expression of the antimicrobial peptides.

Hepatocellular carcinoma treated with percutaneous radio-frequency ablation: usefulness of power Doppler US with a microbubble contrast agent in evaluating therapeutic response-preliminary results

PURPOSE

To evaluate the usefulness of power Doppler ultrasonography (US) with a microbubble contrast agent in assessing the therapeutic response of hepatocellular carcinomas (HCCs) treated with percutaneous radio-frequency (RF) ablation.

MATERIALS AND METHODS

Forty patients with 45 nodular HCC lesions 1.0-3.8 cm in diameter underwent power Doppler US before and after intravenous injection of a microbubble contrast agent. The same procedures were repeated after US-guided percutaneous RF ablation. The results of these studies were compared with those of three-phase helical computed tomography (CT) performed immediately after RF ablation.

RESULTS

Before RF ablation, nonenhanced power Doppler US demonstrated flow signals within tumor in 33 of 45 HCCs. After contrast agent administration, flow signals increased or newly appeared in all cases. After RF ablation, none of the ablated tumors showed intratumoral flow signals at nonenhanced power Doppler US, whereas six showed marginal intratumoral flow signals at contrast agent-enhanced power Doppler US. These six tumors were found to have small enhancing foci, suggestive of viable tumor, in corresponding areas at immediate follow-up CT. Additional RF ablation or transcatheter arterial chemoembolization was performed in these tumors.

CONCLUSION

The results of power Doppler US with a microbubble contrast agent in HCCs treated with RF ablation correlated well with those of contrast-enhanced CT. Preliminary data suggest that contrast-enhanced power Doppler US can be a promising noninvasive technique for assessing therapeutic response.

Development of a real-time RT-PCR assay for plasma membrane calcium ATPase isoform 1 (PMCA1) mRNA levels in a human breast epithelial cell line

The plasma membrane Ca(2+) pump is a key regulator of cytosolic free Ca(2+). Recent studies have demonstrated the dynamic expression of the plasma membrane Ca(2+) pump in a variety of cell types. Furthermore, alterations in plasma membrane calcium pump activity have now been implicated in human disease. In this study, the development of a technique to quantitatively assess mRNA expression of the human plasma membrane Ca(2+) ATPase (PMCA1) isoform of the plasma membrane Ca(2+) pump, using a real-time reverse transcriptase-polymerase chain reaction (real-time RT-PCR) assay in a human breast epithelial cell line (MCF-7) is described. The sequences of the PMCA1 primers and probe for real-time RT-PCR are presented. The results also indicate that PMCA1 mRNA can be normalized to both 18S ribosomal RNA (18S rRNA) and human glyceraldehyde-3-phosphate dehydrogenase (hGAPDH) in MCF-7 cells. Real-time RT-PCR will be most useful in assessing PMCA1 mRNA expression in cases where only low amounts of RNA are available and/or when numerous samples must be assessed simultaneously.

Gram-negative bacteria-binding protein, a pattern recognition receptor for lipopolysaccharide and beta-1,3-glucan that mediates the signaling for the induction of innate immune genes in Drosophila melanogaster cells

Pattern recognition receptors, non-clonal immune proteins recognizing common microbial components, are critical for non-self recognition and the subsequent induction of Rel/NF-kappaB-controlled innate immune genes. However, the molecular identities of such receptors are still obscure. Here, we present data showing that Drosophila possesses at least three cDNAs encoding members of the Gram-negative bacteria-binding protein (DGNBP) family, one of which, DGNBP-1, has been characterized. Western blot, flow cytometric, and confocal laser microscopic analyses demonstrate that DGNBP-1 exists in both a soluble and a glycosylphosphatidylinositol-anchored membrane form in culture medium supernatant and on Drosophila immunocompetent cells, respectively. DGNBP-1 has a high affinity to microbial immune elicitors such as lipopolysaccharide (LPS) and beta-1,3-glucan whereas no binding affinity is detected with peptidoglycan, beta-1,4-glucan, or chitin. Importantly, the overexpression of DGNBP-1 in Drosophila immunocompetent cells enhances LPS- and beta-1,3-glucan-induced innate immune gene (NF-kappaB-dependent antimicrobial peptide gene) expression, which can be specifically blocked by pretreatment with anti-DGNBP-1 antibody. These results suggest that DGNBP-1 functions as a pattern recognition receptor for LPS from Gram-negative bacteria and beta-1, 3-glucan from fungi and plays an important role in non-self recognition and the subsequent immune signal transmission for the induction of antimicrobial peptide genes in the Drosophila innate immune system.

CM1, a possible novel activation molecule on human lymphocytes

CM1 (centrocyte/-blast marker 1) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on some tonsillar germinal center (GC) B cells. In single flow cytometric analysis, the bone marrow did not express these molecules nor did the PBMC or the thymocytes. The peripheral B lymphocytes showed more than 90% positive, while the peripheral T lymphocytes showed approximately 60% positive at 48 h after activation by PMA/ionomycin, respectively. A western blot analysis and an immunoprecipitation for CM1 showed a band at 70 kDa. Cross-linking of CM1 with anti-CM1 mAb induced apoptosis of the GC B cells (CD38(+)IgD(-)). Immunohistochemical staining revealed that the CM1 molecule is distributed over the entire area except the proximal dark zone of the tonsillar germinal centers. These results suggest that the CM1 molecule might be involved in differentiation of the germinal center B cells as one of the novel centrocyte markers.

Cross-species immunoreactivity of airway mucin as revealed by monoclonal antibodies directed against mucins from human, hamster, and rat

Airway mucin plays crucial role in host-defense and has been implicated in pathophysiology of various airway diseases including asthma and cystic fibrosis. The analysis of airway mucin has been hampered mostly by the lack of specific and efficient methods for the detection of mucin. Recent production of antibodies against airway mucin from several species and also the development of immunoassay procedures make it more efficient to study the airway mucin. However, the cross-species immunoreactivity of antibodies against airway mucin has not been clearly demonstrated and this prompted us to investigate the cross-species immunoreactivity of monoclonal antibodies against human (HM02), hamster (HTA), and rat airway mucin (RT03), which is three most widely used species in the study of mucin. All the monoclonal antibodies (MAbs) used in this study is IgM isotype and recognizes N-acetyl-galactosamine-linked carbohydrate core or backbone portion of airway mucin. In enzyme-linked immunoadsorbent assay (ELISA), Western blot, immunoprecipitation, and immunohistochemical staining experiments, it was demonstrated that human and hamster airway mucin showed strong cross-species immunoreactivity. However, rat airway mucin did not show any cross-species immunoreactivity against human and hamster airway mucin. Endotoxin-induced secretory cell metaplasia and hence the increase in mucin release from hamster airway mucin could be detected with antibodies against hamster and human airway mucin in vivo and in vitro. However, the same increase from rat airway could only be detected with antibody against rat airway mucin but not with antibodies against human and hamster airway mucin. In addition, the increase in mucin release from asthmatic patients could be detected with antibodies against human and hamster airway mucin but not with the antibody against rat airway mucin. The data from the present study implicates that the carbohydrate chain of human and hamster airway mucin, but not that of rat airway mucin, share common antigenic structure. In case of the interspecies use of the antibodies against airway mucin, it would be more desirable to clearly identify the cross-species immunoreactivity otherwise might lead to erroneous results.

New mutations of the HPRT gene in Lesch-Nyhan syndrome

Lesch-Nyhan syndrome is an X-linked recessive disorder involving the purine metabolism, with resultant hyperuricemia, choreoathetosis, self-mutilation, and profound neurologic dysfunction. A deficiency of the enzyme hypoxanthine guanine phosphoribosyl-transferase is responsible for the disease. The human HPRT gene is located at Xq26-27 and consists of 57 base pairs. At least 2,000 mutations throughout the HPRT gene coding region from exon 1-9 have been reported. Four patients from three Chinese families were diagnosed with Lesch-Nyhan syndrome according to the clinical and laboratory findings. DNA studies revealed the first family (Patients 1 and 2) had a missense mutation in exon 3 of the HPRT encoding region. This novel mutation occurs in the hot spot of the HPRT gene. The second family (Patient 3) was found to have a missense mutation in exon 8 of the HPRT gene. The third family (Patient 4) carried a mutation in the splicing region of intron 4 of the HPRT gene. All three mutations were de novo.

Detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers: accuracy of helical CT in transplant patients

OBJECTIVE

The purpose of this study was to evaluate the diagnostic efficacy of three-phase helical dynamic CT in the detection and characterization of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers.

SUBJECTS AND METHODS

Three-phase helical dynamic CT in 41 patients with liver cirrhosis was evaluated prospectively before orthotopic liver transplantation. The numbers of hepatocellular carcinomas and dysplastic nodules were assessed in the explanted livers and compared with pretransplantation CT findings.

RESULTS

Examination of the explanted livers revealed 21 hepatocellular carcinomas in 15 patients and 23 dysplastic nodules in 10 patients. The size of the hepatocellular carcinomas was 0.6-5. 0 cm (mean, 1.9 cm), and that of the dysplastic nodules was 0.7-2.0 cm (mean, 1.0 cm). The use of helical dynamic CT enabled detection of 15 of 21 hepatocellular carcinomas (sensitivity, 71%) and nine of 23 dysplastic nodules (sensitivity, 39%). Patient sensitivity and specificity in the detection of hepatocellular carcinomas were 80% (12/15) and 96% (25/26), respectively, and for dysplastic nodules, 50% (5/10) and 97% (30/31), respectively.

CONCLUSION

Three-phase helical dynamic CT is relatively insensitive for detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers, especially for dysplastic nodules and hepatocellular carcinomas smaller than 2 cm.

Clinical impact of ex vivo differentiated myeloid precursors after high-dose chemotherapy and peripheral blood progenitor cell rescue

The infusion of ex vivo differentiated myeloid precursors may be able to shorten the period of obligatory neutropenia after high-dose chemotherapy and peripheral blood progenitor cell rescue by providing cells capable of differentiating to mature neutrophils within days of infusion. To test this hypothesis, 21 female patients with metastatic breast cancer underwent progenitor cell mobilization with cyclophosphamide, etoposide and G-CSF. CD34+ cells from one to two leukapheresis products were isolated and placed in suspension culture with a serum-free growth medium supplemented with PIXY321. The cultures were maintained for 12 days with subcultures initiated on day 7. The remaining leukapheresis products were cryopreserved in an unmanipulated state. Forty-eight hours after completing high-dose cyclophosphamide, thiotepa and carboplatin, the cryopreserved progenitors were infused, followed 1 to 24 h later by infusion of the differentiated myeloid precursors. In one patient, the cultured cells were labeled with Indium-111 with nuclear imaging performed up to 48 h post infusion. The differentiated myeloid precursors were suitable for infusion in 17 of the patients with a median 13-fold expansion of total nucleated cells. A range of 5.6 to 1066 x 10(7) nucleated cells were infused. Morphologically the cells were predominantly of myeloid lineage (63%) with a median 41% of the cells expressing CD15. No untoward effects were noted with the infusion of the cultured cells. The median days to neutrophil and platelet recovery were 8 and 10 days, respectively. There was a significant relationship (r = 0.67, P = 0.007) between the dose of differentiated myeloid precursors (CD15+ cells) and the depth and duration of neutropenia; a similar relationship, however, was also observed with the dose of cryopreserved CD34+ cells. After infusion of the radiolabeled myeloid precursors, a pattern of distribution similar to radio-labeled granulocytes was noted with uptake detected initially in the lungs and subsequently the reticulo-endothelial system. The impact of differentiated myeloid precursors on neutropenia as an adjunct to high-dose chemotherapy and peripheral blood progenitor cell rescue remains unclear from this study. Further study with controlled doses of cryopreserved progenitors and escalating doses of differentiated myeloid precursors is required.

Inhibition of mitogen-activated protein kinase by a Drosophila dual-specific phosphatase

The Drosophila extracellular signal-regulated kinase (DERK) mitogen-activated protein kinase (MAPK) is involved in the regulation of multiple differentiation and developmental processes. Tight control of MAPK activity is critical for normal cell behaviour. We identified a novel Drosophila MAPK phosphatase (DMKP) cDNA from the expressed-sequence-tag database and characterized it. Analysis of the nucleotide sequence revealed an open reading frame encoding the 203-amino acid protein, with a calculated molecular mass of 23 kDa, which has a high amino acid sequence similarity with 'VH1-like' dual-specific phosphatases at the broad region near the catalytic sites. The expression of DMKP mRNA occurs from the late larval stages to adulthood in Drosophila development. The recombinant DMKP protein produced in yeast retained its phosphatase activity. When expressed in Schneider cells, DMKP dose-dependently inhibited DERK and Drosophila c-Jun N-terminal kinase activities with high selectivity towards DERK. However, DMKP did not have any affect on Drosophila p38 activity. When DMKP was expressed in yeast, it down-regulated the fus1-lacZ trans-reporter gene of the pheromone MAPK pathway without any significant effect on the high-osmolarity-glycerol-response pathway.

Plasma tumor necrosis factor alpha levels and insulin sensitivity in hypertensive subjects

Recent studies have shown that tumor necrosis factor-alpha (TNFalpha), secreted by macrophage, adipocyte and muscle cells, are associated with insulin resistance syndrome i.e., hyperinsulinemia, hypertriglyceridemia and decreased high density lipoprotein (HDL) cholesterol levels. However, it is unclear whether plasma TNFalpha levels relate to insulin resistance syndrome in subjects with essential hypertension who are also characterized by an insulin resistance state. We recruited 85 nondiabetic subjects (45 men and 40 women) with essential hypertension and 85 nondiabetic subjects who were matched for age, sex and body mass index (BMI) to determine their fasting plasma glucose, insulin and lipoprotein concentrations, their glucose and insulin responses to an oral glucose challenge, and their degrees of insulin resistance. Fasting plasma leptin and TNFalpha levels were measured by radioimmunoassay and chemiluminescent enzyme immunometric assay respectively. Total body fat mass was assessed by the bioelectrical impedance method. The results showed that fasting plasma leptin levels were similar between hypertensive and normotensive subjects (7.9 +/- 0.6 vs 7.4 +/- 0.7 ng/ml, p=0.190). Fasting plasma TNFalpha concentrations were not different between subjects with hypertension and normotension (10.5 +/- 0.5 vs 9.8 +/- 0.4 pg/ml, p=0.360). Fasting plasma TNFalpha concentrations were not different across three subgroups of the insulin resistance both in hypertensive patients (8.4 +/- 0.4 vs. 10.9 +/- 1.6 vs. 9.9 +/- 1.0 pg/ml, p=0.297) and normotensive subjects (9.2 +/- 0.7 vs. 9.3 +/- 0.9 vs. 9.7 +/- 0.9 pg/ml, p=0.875). Fasting plasma TNFalpha values showed significantly positive correlations with triglyceride concentrations (p<0.03) but negative correlation with HDL cholesterol concentrations (p<0.04) in normotensive but not in hypertensive individuals. These relations persisted even after adjustment for BMI and total fat mass. In conclusion, our data indicated that circulating levels of TNFalpha did not differ between hypertensive subjects and normotensive controls. Plasma TNFalpha concentrations correlated positively with fasting plasma triglyceride levels and negatively with HDL cholesterol concentrations in normotensive but not in hypertensive subjects. The influence of TNFalpha on carbohydrate and lipoprotein metabolism in hypertensive patients deserves further investigations.

The genetic relationships of two subspecies of striped field mice, Apodemus agrarius coreae and Apodemus agrarius chejuensis

We obtained 282 base pairs of sequence for the mitochondrial control region of 70 individuals of Korean striped field mice Apodemus agrarius coreae and Apodemus agrarius chejuensis to determine the levels of genetic divergence between these morphologically distinct taxa. The DNA sequences showed more genetic diversity (pi) in A. agrarius coreae (2.98%) than in A. agrarius chejuensis (1.86%). Our data do not support the current concept that the two morphotypes are different species, but phylogenetic analysis indicates that animals of A. agrarius coreae with large body size from Wan Island cluster with the large-bodied A. agrarius chejuensis, and should be included in that taxon. As currently accepted A. agrarius coreae is not strictly monophyletic, because the large-bodied samples cluster within the range of mitochondrial variation of A. agrarius chejuensis. The fact that the two morphotypes do not share mitochondrial haplotypes (chi2=66, P < 0.001) suggests that there is little gene flow between them. A molecular clock estimate suggests that the two subspecies might have been isolated at the time of separation of the islands from the mainland.

Association between birth weight and insulin sensitivity in healthy young men in Korea: role of visceral adiposity

Recent studies have demonstrated decreased insulin sensitivity in individuals with low birth weight. This study was performed to examine whether abdominal obesity is a link between insulin resistance and low birth weight. We studied the relationships between birth weight and insulin secretion, insulin sensitivity, and various anthropometric indices including visceral fat area in 22 healthy young Korean adults. Birth weight correlated significantly with diastolic blood pressure (r=-0.47, P<0.05) and insulin sensitivity index (S(I)) measured by a frequently sampled intravenous glucose tolerance test (FSIGT) (r=0.54, P<0.05), but not with insulin secretory indices such as acute insulin responses during FSIGT (r=-0.35, NS) or hyperglycemic clamp (r=0.17, NS) and submaximum insulin response during hyperglycemic clamp (r=0.10, NS). S(I) correlated significantly with abdominal obesity measurements such as waist circumference (r=-0.48, P<0.05), waist-to-hip ratio (r=-0.53, P<0.05) and visceral fat area (r=-0.58, P<0.01). However, we could not find significant correlation between birth weight and any of the abdominal obesity measurements (r=-0.35 for waist-to-hip ratio, r=-0.22 for visceral fat area, and r=-0.24 for visceral-to-subcutaneous fat ratio; NS for all). The present data confirm that low birth weight is associated with insulin resistance in adult life. However, our data suggest that the association between low birth weight and insulin resistance is not mediated by abdominal obesity.

Urinary excretion of hippuric acid after consumption of nonalcoholic beverages

To investigate the types and quantities of beverages that increase urinary hippuric acid (HA) excretion, the authors recruited 137 healthy medical students and divided them into quintiles according to consumption of benzoic acid (BA) in beverages. Using chromatography, urinary HA before and 1.5 hours and 3 hours after consumption of various beverages and BA consumption in the beverages were measured. The mean age of the group was 24.2 years; 21 were female. The range of BA in 13 beverages was 0-1.02 mg/mL. The geometric means of urinary HA before consuming them in five groups were 0.276, 0.270, 0.207, 0.262, and 0.316 g/L, respectively (p = 0. 567); 1.5 hours after consuming the beverages, they were 0.210, 0. 603, 1.026, 1.066, and 1.688 g/L, respectively, and significantly increased after adjustment for urinary HA before ingestion (p < 0. 001). Three hours after ingestion, the geometric means were 0.160, 0. 232, 0.306, 0.287, and 0.337 g/L, respectively (p < 0.001). The authors estimate that beverages that contain more than 100 mg BA could increase urinary HA excretion significantly, up to 1.12 g/L without toluene exposure. Checking dietary and beverage-intake histories is essential in the interpretation of urinary HA concentrations in population studies.

Associations between lipoprotein lipase gene polymorphisms and insulin resistance in coronary heart disease

BACKGROUND

Lipoprotein lipase (LPL) is a crucial enzyme in plasma lipoprotein metabolism. Variants of the LPL gene (Pvu II and Hind III polymorphisms) may increase the risk of developing coronary heart disease (CHD) but their effect on insulin resistance remains unknown. The present study was conducted to examine whether DNA variations of the LPL gene were related to insulin resistance, carbohydrate and lipid risk factors for CHD in nondiabetic individuals.

METHODS

Pvu II and Hind III allele status of the LPL gene and fasting plasma glucose, insulin and lipid values were determined in nondiabetic men with angiographically documented CHD (n = 102) and in a control group (n = 145). Plasma glucose and insulin responses to a 75-g oral glucose tolerance test and insulin resistance as measured by an insulin suppression test were also carried out in 46 (45%) of the patients with CHD and in 73 (50%) of the control individuals.

RESULTS

The allele frequencies of LPL Pvu II and Hind III were not significantly different between the CHD patients and the controls. No association was found between Pvu II status and blood pressure, fasting plasma glucose, insulin, lipid levels or insulin resistance in patients with CHD. Nevertheless, compared with individuals with the Hind III H2H2 allele, CHD patients carrying the H1 allele (H1H1 + H1H2) were more insulin resistant, as indicated by higher steady state plasma glucose concentrations (253 +/- 87 vs 200 +/- 74 mg/dl, p = 0.032).

CONCLUSIONS

We suggest that the LPL gene Hind III allele might be associated with insulin resistance in nondiabetic men with CHD. However, further studies with larger populations of both sexes will be required to confirm this finding.

Methylprednisolone increases plasma leptin levels in Graves' hyperthyroidism patients with active Graves' ophthalmopathy

Whether leptin, a product of the ob gene, can be stimulated by glucocorticoid administration has been an issue of controversy. We investigated the effect of intravenous administration of methylprednisolone (500 mg/day x 3 days) on plasma levels of leptin in 16 patients (female/male = 11/5) with Graves' hyperthyroidism and active ophthalmopathy who received pulse therapy. Significant elevation of plasma leptin levels started at the eighth hour (13.9+/-1.8 ng/mL, p=0.042) and lasted until the 72nd hour (21.2+/-5.0 ng/mL, p=0.009), as compared with basal levels (8.8+/-1.2 ng/mL). When methylprednisolone was replaced with oral prednisolone (10 mg three times per day x 2 weeks), no difference in plasma leptin levels was noted compared with basal measurement. Under methylprednisolone administration, a significant suppression of tumor necrosis factor-alpha began at the 24th hour (8.1+/-1.3 pg/mL, p=0.004) and lasted until the 48th hour (8.1+/-1.0 pg/mL, p=0.008), as compared with basal measurement (12.5+/-1.5 pg/mL). Compared with basal levels (93+/-2 mg/dL), significant elevation in the plasma glucose level started at the third hour (135+/-10 mg/dL, p=0.000) and lasted until the 72nd hour (110+/-4 mg/dL, p=0.019). The timing of serum insulin elevation approximated that of plasma glucose (3 hours: 14+/-3 microU/mL, p=0.006) and lasted until the end of prednisolone administration (2 weeks: 12+/-2 microU/mL, p=0.044), when compared with basal levels (14+/-3 microU/mL). We concluded that the parental administration of pharmacological doses of methylprednisolone to patients with Graves' hyperthyroidism could acutely raise their plasma level of leptin.

Mini-laparoscopic reduction of intussusception for children

The success of mini-laparoscopic cholecystectomy and splenectomy has encouraged the application of this new technique in children with non-complicated intussusception. Here, we report on the use of this technique in two children, aged 21 and 24 months, respectively, who had failed saline enema reduction of ileocolic intussusception. Under a 2-mm videoscopic visualization, the intussuscepted bowel was identified and reduced with the assistance of a 2-mm working port placed at the right lower abdominal area and a 5- to 10-mm working port placed at the supraumbilical area. An intussuscepted lymph node at the ileocecal area, as the lead point, was removed at the time of the procedure in one child. Both patients experienced relief of symptoms the day after operation and resumed a regular diet on the first post-operative day. No recurrence or complications, including abscess and wound infection, occurred. These findings suggest that mini-laparoscopic reduction is a safe procedure for children with uncomplicated intussusception. Moreover, the procedure provides better cosmesis than conventional laparoscopic techniques.