Healthy Human Beings Research Articles

Fibrinolytic system of the armadillo Chaetophractus villosus (Xenarthra, Dasypodidae)

The fibrinolytic mechanism in the armadillo Chaetophractus villosus (Mammalia, Xenarthra, Dasypodidae) quite unknown until now was studied. Results were compared with those corresponding to healthy adult human beings. Whole blood lysis time and diluted blood lysis time were not detectable in armadillos. Euglobulin clot lysis time and plasminogen activity (Plg) were lower than in healthy humans. We established the presence of the fibrinolytic system in Ch. villosus through the measurement of fibrin fibrinogen degradation products. The activity of the plasminogen activator inhibitor was two to four times greater than in healthy humans. The activity of the alpha 2 anti-plasmin (α2AP) was similar and displaced toward lower values. The Plg/α2AP relation was lower. The results obtained suggest that Ch. villosus has a hypercoagulable and hypofibrinolytic profile. Our findings are not only the first contribution to elucidate the physiology of the fibrinolytic system in Xenarthra but also contribute to develop an animal model for studies in haemostasis and thrombosis.

Safe at any scale? Food scares, food regulation, and scaled alternatives

The 2006 outbreak of E. coli O157:H7, traced to bagged spinach from California, illustrates a number of contradictions. The solutions sought by many politicians and popular food analysts have been to create a centralized federal agency and a uniform set of production standards modeled after those of the animal industry. Such an approach would disproportionately harm smaller-scale producers, whose operations were not responsible for the epidemic, as well as reduce the agroecological diversity that is essential for maintaining healthy human beings and ecosystems. Why should responses that only reinforce the problem be proffered? We use the framework of accumulation and legitimation to suggest corporate and government motives for concealing underlying problems and reinforcing powerful ideologies of individualism, scientism, and centralizing authority. Food safety (or the illusion of safety) is being positioned to secure capital rather than public welfare. We propose implementing the principle of subsidiarity as a more democratic and decentralized alternative. Because full implementation of this principle will be resisted by powerful interests, some promising intermediate steps include peer production or mass collaboration as currently applied to disease prevention and surveillance, as well as studying nascent movements resisting current food safety regulations.

Pharmacological Modulation of Gap Junction Function with the Novel Compound Rotigaptide: A Promising New Principle for Prevention of Arrhythmias

Existing anti-arrhythmic therapy is hampered by lack of efficacy and unacceptable side effects. Thus, ventricular tachycardia and fibrillation remains the strongest predictor of in-hospital mortality in patients with myocardial infarction. In atrial fibrillation, rhythm control with conventional ion channel blockers provide no therapeutic benefit relative to rate control. Several lines of research indicate that impaired gap junctional cell-to-cell coupling between neighbouring cardiomyocytes is critical for the development of cardiac re-entry arrhythmias. Rotigaptide is the first drug that has been developed to prevent arrhythmias by re-establishing gap junctional intercellular communication. During conditions with acute cardiac ischaemia, rotigaptide effectively prevents induction of both ventricular and atrial tachyarrhythmia. Moreover, rotigaptide effectively prevents ischaemia reperfusion arrhythmias. At the cellular level, rotigaptide inhibits ischaemia-induced dephosphorylation of Ser297 and Ser368, which is considered important for the gating of connexin43 gap junction channels. No drug-related toxicity has been demonstrated at plasma concentrations 77,000 times above therapeutic concentrations. In rats and dogs, rotigaptide reduces infarct size following myocardial infarction. A series of phase I trials has been completed in which rotigaptide has been administered intravenously to ~200 healthy persons. No drug-related side effects have been demonstrated in healthy human beings. Clinical safety, tolerability and efficacy in patients with heart disease are being evaluated in ongoing clinical trials. Rotigaptide represents a pioneering pharmacological principle with a highly favourable preclinical and clinical safety profile, which makes this molecule a promising drug candidate for the prevention of cardiac arrhythmias.

Free Fatty Acids Have More Potent Effects on Gastric Emptying, Gut Hormones, and Appetite Than Triacylglycerides

The effects of fat on gastric emptying (GE), gut hormones, and energy intake are dependent on digestion to free fatty acids (FFAs). In animals, small intestinal oleic acid inhibits energy intake more potently than the triacylglyceride (TG) triolein, but there is limited information about the comparative effects of FFA and TG in human beings. We compared the effects of FFA and TG on GE, gut hormone secretion, appetite, and energy intake in healthy males. Nine men (age, 23 +/- 2 y; body mass index, 22 +/- 1 kg/m(2)) were studied on 3 occasions to evaluate the effects of (1) 40 g oleic acid (FFA, 1830 kJ), (2) 40 g macadamia oil (TG, 1856 kJ; both 600-mL oil-in-water emulsions stabilized with 4% milk protein and labeled with 15 MBq (123)I), or (3) 600 mL 4% milk protein (control, 352 kJ), administered intragastrically, on GE, plasma cholecystokinin (CCK) and peptide-YY (PYY) levels, appetite perceptions, and subsequent energy intake. GE of FFA was much slower than that of TG (P < .05), with greater retention of FFA, than TG, in the proximal stomach (P < .001). Hunger was less (P < .05), and fullness was greater (P < .05), after FFA when compared with control and TG. Increases in plasma CCK and PYY levels were greater after FFA than TG or control (P < .05). Energy intake tended to be less after FFA compared with TG (control, 4754 +/- 610 kJ; TG, 5463 +/- 662 kJ; FFA, 4199 +/- 410 kJ). FFAs empty from the stomach more slowly, but stimulate CCK and PYY and suppress appetite more potently than TG in healthy human beings.

Copy number variations and clinical cytogenetic diagnosis of constitutional disorders

The recent appreciation of widespread copy number variation in the genomes of healthy human beings has presented a significant challenge to clinical cytogeneticists who wish to use genome-wide array comparative genomic hybridization (CGH) assays for clinical diagnostic purposes. Clinical cytogeneticists need to differentiate between copy number variants (CNVs) that are likely to be pathogenic and CNVs that are less likely to contribute to an affected individual's clinical presentation. Unfortunately, our knowledge of the phenotypic effects of most CNVs is minimal, leading to the classification of many CNVs as genomic imbalances of unknown clinical significance. This has caused many laboratories to resist the use of higher-resolution genome-wide array CGH assays for clinical purposes. Ironically, the accumulation and annotation of such array CGH data can lead to the rapid identification of pathogenic CNVs and the definition of new genomic syndromes that, in turn, are useful for accurate clinical genetic diagnoses.

Effect of potassium chloride on gastric acid secretion and gastrin release in humans

The effect of potassium chloride on gastric acid secretion and gastrin release was studied in 6 healthy human beings. On 3 separate days and in random order, subjects received an intragastric infusion of 0.5 L of a glucose-saline solution to which had been added 40 mmol KCl, 40 mmol NaCl, or no additional salts. All test solutions stimulated acid secretion and gastrin release to a similar degree. While potassium ions play a critical role in acid secretion by parietal cells (via the H+, K(+)-ATPase), KCl administered into the gastric lumen at a concentration of 80 mmol/L has no effect on acid secretion in man.

Arginine 16 Glycine β 2-Adrenoceptor Polymorphism and Cardiovascular Structure and Function in Patients with Heart Failure

The beta2/beta1 adrenoceptor ratio increases in congestive heart failure (CHF), making the heart relatively more dependent on inotropic, lusitropic, and chronotropic stimulation by the beta2-adrenergic receptor (ADRB2). In healthy human beings, those who are homozygous for arginine (Arg) at amino acid 16 of the ADRB2 have reduced receptor function when compared with individuals homozygous for glycine (Gly) at this position. The cardiovascular effects of the Arg16Gly polymorphism of the ADRB2 in CHF are not well understood. The aim of this study was to examine the influence of common polymorphisms of the ADRB2 on cardiovascular structure and function in patients with CHF. Echocardiography, neurohormonal assays, and exercise tests were performed in 68 healthy individuals and 95 patients with CHF. All of the patients with CHF were stable, New York Heart Association class II to III, of ischemic or nonischemic cause, with an ejection fraction of 40% or less. Of the patients with CHF, 16 were Arg/Arg, 36 were Arg/Gly, and 43 were Gly/Gly at amino acid 16. In those without CHF, the Arg16Gly polymorphism of the ADRB2 had no effect on cardiovascular function. In contrast, in CHF, Arg/Arg homozygotes had higher plasma norepinephrine and atrial natriuretic peptide levels, greater left atrial diastolic dimension, higher peak velocity of early/late diastolic filling ratio, and shorter deceleration time compared with Gly16 homozygotes. Furthermore, Arg16 homozygotes had reduced exercise tolerance compared with Gly16 homozygotes (evidenced by shorter exercise duration and lower peak oxygen consumption per unit time), and a lesser chronotropic response to exercise. In patients with CHF, but not in demographically matched healthy persons, the Arg16Gly polymorphism of the ADRB2 exerts important effects on cardiovascular structure and function, neurohormonal activation, and exercise tolerance.

Gamma Interferon Secretion by Human Vγ2Vδ2 T Cells after Stimulation with Antibody against the T-Cell Receptor plus the Toll-Like Receptor 2 Agonist Pam3Cys

Circulating Vgamma2Vdelta2 T-cell populations in healthy human beings are poised for rapid responses to bacterial or viral pathogens. We asked whether Vgamma2Vdelta2 T cells use the Toll-like receptor (TLR) family to recognize pathogen-associated molecular pattern molecules and to regulate cell functions. Analysis of expanded Vgamma2Vdelta2 T-cell lines showed the abundant presence of TLR2 mRNA, implying that these receptors are important for cell differentiation or function. However, multiple efforts to detect TLR2 protein on the cell surface or in cytoplasmic compartments gave inconsistent results. Functional assays confirmed that human Vgamma2Vdelta2 T cells could respond to the TLR2 agonist (S)-(2,3-bis(palmitoyloxy)-(2RS)-propyl)-N-palmitoyl-(R)-Cys-(S)-Ser(S)-Lys4-OH trihydrochloride (Pam3Cys), but the response required coincident stimulation through the gammadelta T-cell receptor (TCR). Dually stimulated cells produced higher levels of cytoplasmic or cell-free gamma interferon and showed increased expression of the lysosome-associated membrane protein CD107a on the cell surface. A functional TLR2 that requires coincident TCR stimulation may increase the initial potency of Vgamma2Vdelta2 T-cell responses at the site of infection and promote the rapid development of subsequent acquired antipathogen immunity.

Biological material on inhaled coarse fraction particulate matter activates airway phagocytes in vivo in healthy volunteers

In vitro, endotoxin on coarse fraction particulate matter (PM2.5-10) accounts for the majority of the ability of PM2.5-10 to induce cytokine responses from alveolar macrophages. We examined in vivo whether inhaled PM2.5-10 from local ambient air induce inflammatory and immune responses in the airways of healthy human beings and whether biologic material on PM2.5-10 accounts for these effects. On 3 separate visits, 9 healthy subjects inhaled nebulized saline (0.9%, control), PM2.5-10 collected from local ambient air that was heated to inactivate biological material (PM2.5-10-), or nonheated PM (PM2.5-10+). PM2.5-10 deposition (approximately 0.65 mg/subject) targeted the bronchial airways (confirmed by using radiolabeled aerosol), and induced sputum was obtained 2 to 3 hours postinhalation for analysis of cellular and biochemical markers of inflammation and innate immune function. Inhaled PM2.5-10+ induced elevated inflammation (% PMNs, macrophage mRNA TNF-alpha), increased eotaxin, upregulated immune surface phenotypes on macrophages (mCD14, CD11b, HLA-DR), and increased phagocytosis (monocytes) versus saline (P < .05). Biological inactivation of PM2.5-10 (PM2.5-10-) had no effect on neutrophilia but significantly (P < .05) attenuated mRNA TNF-alpha, eotaxin levels, cell surface marker responses, and phagocytosis. Biological components of PM2.5-10 are not necessary to induce neutrophil responses but are essential in mediating macrophage responses. The ability of PM2.5-10 to activate monocytic cells and potentially skew the airways toward an allergic phenotype by enhancing eotaxin levels may enhance responses to allergens or bacteria in individuals with allergy. PM2.5-10 might enhance the response of individuals with allergy to airborne bacteria.

In vivo oxidative metabolism of a major peroxidation-derived DNA adduct, M1dG.

3-(2-Deoxy-beta-D-erythro-pentofuranosyl)pyrimido[1,2-alpha]purin-10(3H)-one (M1dG) is a DNA adduct arising from the reaction of 2-deoxyguanosine with the lipid peroxidation product, malondialdehyde, or the DNA peroxidation product, base propenal. M1dG is mutagenic in bacteria and mammalian cells and is present in the genomic DNA of healthy human beings. It is also detectable, albeit at low levels, in the urine of healthy individuals, which may make it a useful biomarker of DNA damage linked to oxidative stress. We investigated the possibility that the low urinary levels of M1dG reflect metabolic conversion to derivatives. M1dG was rapidly removed from plasma (t(1/2) = 10 min) after i.v. administration to rats. A single urinary metabolite was detected that was identified as 6-oxo-M1dG by MS, NMR spectroscopy, and independent chemical synthesis. 6-Oxo-M1dG was generated in vitro by incubation of M1dG with rat liver cytosols, and studies with inhibitors suggested that xanthine oxidase and aldehyde oxidase are involved in the oxidative metabolism. M1dG also was metabolized by three separate human liver cytosol preparations, indicating 6-oxo-M1dG is a likely metabolite in humans. This represents a report of the oxidative metabolism of an endogenous DNA adduct and raises the possibility that other endogenous DNA adducts are metabolized by oxidative pathways. 6-Oxo-M1dG may be a useful biomarker of endogenous DNA damage associated with inflammation, oxidative stress, and certain types of cancer chemotherapy.

Inhibitory Effect of Anti-HER-2 Anti-CD3 Bi-specific Antibody on the Growth of Gastric Carcinoma

To evaluate the effect of anti-HER-2 × anti-CD3 bi-specific antibody (BsAb) on the growth of HER-2/neu-expressing human gastric carcinoma in vitro and in vivo , an MTT assay was carried out to test the inhibitive rates of herceptin, anti-CD3 and BsAb antibodies on SGC-7901 gastric carcinoma cells. Immunocytochemistry methods were used to test the HER-2 level of SGC-7901. Nude mice models were employed to test the effect of HER-2 CD3 BsAb combined with effector cells (peripheral blood lymphatic cells of healthy human beings) on the growth of tumors in animals. Compared with that of the untreated control group, the tumor cell growth rates in vitro and in vivo will both be significantly inhibited when treated with effector cells combined with anti-CD3 McAb, herceptin or HER2 CD3 BsAb ( p p in vitro and in vivo.

Urinary Excretion of Polyethylene Glycol 3350 during Colonoscopy Preparation

Whole gut lavage with a polyethylene glycol electrolyte solution (PEG) is a common bowel cleansing method for diagnostic and therapeutic colon interventions. Absorption of orally administered PEG from the gastrointestinal tract in healthy human beings is generally considered to be poor. In patients with inflammatory bowel disease (IBD), intestinal permeability and PEG absorption were previously reported to be higher than in normal subjects. In the current study, we investigated the absorption of PEG 3350 in patients undergoing routine gut lavage. Urine specimens were collected for 8 hours in 24 patients undergoing bowel cleansing with PEG 3350 for colonoscopy. The urinary excretion of PEG 3350, measured by size exclusion chromatography, ranged between 0.01 and 0.51 % of the ingested amount, corresponding to 5.8 and 896 mg in absolute amounts, respectively. Mean PEG excretion in patients with impaired mucosa such as inflammation or ulceration of the intestine (0.24 % +/- 0.19, n = 11) was not significantly higher (p = 0.173) compared to that in subjects with macroscopically normal intestinal mucosa (0.13 % +/- 0.13, n = 13). The results indicate that intestinal absorption of PEG 3350 is higher than previously assumed and underlies a strong inter-individual variation. Inflammatory changes of the intestine do not necessarily lead to a significantly higher permeability of PEG.

Relationship between S-adenosylmethionine, S-adenosylhomocysteine, asymmetric dimethylarginine, and endothelial function in healthy human subjects during experimental hyper- and hypohomocysteinemia

Experimental hyperhomocysteinemia after an oral methionine or homocysteine load is associated with impaired nitric oxide–dependent vasodilatation in healthy human beings. However, it remains unproven that this effect is mediated by elevations in plasma homocysteine. There is evidence that an increase in plasma homocysteine may increase the formation of asymmetric dimethylarginine (ADMA), an inhibitor of nitric oxide synthase. The methyl groups within ADMA are derived from the conversion of S-adenosylmethionine to S-adenosylhomocysteine intermediates in the methionine/homocysteine pathway. No previous study has assessed the role of methylation status, its impact on ADMA formation, and their association with endothelial function in healthy human beings. In a randomized, placebo-controlled, crossover study, 10 healthy subjects (mean age, 29.1 ± 3.9 years) were administered an oral dose of methionine (0.1 g/kg), l-homocysteine (0.01 g/kg), N-acetylcysteine (NAC) (0.1 g/kg), or placebo. Endothelial function as assessed by flow-mediated dilatation (FMD) of the brachial artery was impaired after both the methionine and homocysteine load compared with placebo at 4 hours (36 ± 15, 67 ± 23 vs 219 ± 26 μm, respectively, P < .001). N-Acetylcysteine had no effect on flow-mediated dilatation. Plasma total homocysteine was significantly elevated at 4 hours after methionine (23.1 ± 6.2) and homocysteine (41.5 ± 8.9) loading, but significantly reduced after NAC 2.4 ± 0.6 vs 7.1 ± 2.1 μmol/L in the placebo ( P < .001). Plasma S-adenosylmethionine/ S-adenosylhomocysteine ratio was significantly ( P < .001) increased at 4 hours after methionine (10.9 ± 0.7) compared with homocysteine (5.4 ± 0.4), NAC (5.0 ± 0.3), and placebo (6.0 ± 0.5). Plasma ADMA concentrations were not altered by any intervention. Our results suggest that endothelial dysfunction due to methionine or homocysteine loading is not associated with an increase in plasma ADMA or a disruption in methylation status.

Effect of early postoperative enteral immunonutrition on wound healing in patients undergoing surgery for gastric cancer

One of the most frequent complications in patients with cancer and malnutrition is the surgical wound healing delay or failure. Some studies have shown that arginine improves wound healing in rodents and in healthy human beings. The main objective of this study was to assess the effect of early postoperative enteral immunonutrition on the wound healing process in patients undergoing surgery for gastric cancer. Sixty six patients with gastric cancer were randomized to receive early postoperative enteral immunonutrition (formula supplemented with arginine, omega-3 fatty acids and ribonucleic acid (RNA)) or an isocaloric-isonitrogenous control. Assessment of wound healing process: (1) Quantification of hydroxyproline deposition in a subcutaneously placed catheter, (2) occurrence of surgical wound healing complications. Sixty patients were analyzed. Patients fed with immunonutrition (n=30) showed higher local hydroxyproline levels (59.7 nmol (5.0-201.8), vs. 28.0 nmol (5.8-89.6) P=0.0018) and significantly lower episodes of surgical wound healing complications (0 vs. 8 (26.7%) P=0.005) when compared to patients fed with the control formula (n=30). Early postoperative enteral nutrition with a formula supplemented with arginine, omega 3 fatty acids and RNA increased hydroxyproline synthesis and improved surgical wound healing in patients undergoing gastrectomy for gastric cancer.

Baseline echocardiographic values for adult male rats

Background Because of safety, repeatability, and portability, clinical echocardiography is well established as a standard for cardiac anatomy, cardiac function, and hemodynamics. Similarly, application of echocardiography in commonly used rat experimental models would be worthwhile. The use of noninvasive ultrasound imaging in the rat is a potential replacement for more invasive terminal techniques. Although echocardiography has become commonly used in the rat, normal parameters for cardiac anatomy and function, and comparison with established human values, have not been reported. Methods A total of 44 Sprague-Dawley male rats had baseline echocardiography replicating a protocol for clinical echocardiography. Results Complete 2-dimensional echocardiography for cardiac anatomy and function was obtained in 44 rats. Hemodynamic parameters could be recorded in 85% of rats. The ejection fraction and fractional shortening values of the left ventricle were similar to those reported for healthy human beings. Pulsed Doppler velocities of atrial systole for mitral valve inflow, pulmonary vein reversal, and Doppler tissue of the lateral mitral valve annulus also had similar means as healthy human beings. The calculated left ventricular mass was at the same order of magnitude as a proportion of body weight of rat to man. All other observations in the clinical protocol were different from those reported in healthy human beings. Conclusion The use of echocardiography for assessment of cardiac anatomy, function, and hemodynamics can be consistently applied to the rat and replicates much of the information used routinely in human echocardiography.

The insulin resistance syndrome.

Insulin-mediated glucose disposal varies widely in apparently healthy human beings. When insulin-resistant individuals cannot secrete enough insulin to overcome this defect, type 2 diabetes occurs. However, the ability of hyperinsulinemia to prevent gross decompensation of glucose tolerance is a mixed blessing, and insulin-resistant/hyperinsulinemic individuals are more likely to be somewhat glucose intolerant, hypertensive, and have a high plasma triglyceride and low high-density lipoprotein cholesterol concentration. These changes increase the risk of cardiovascular disease, and in 1988 these relationships were explicitly addressed and designated as comprising a Syndrome X. The fact that insulin resistance and its consequences are important cardiovascular risk factors has become widely recognized, and the importance of this syndrome was acknowledged in the report of the Adult Treatment Panel III. There has been a rapid increase in the abnormalities associated with insulin resistance/compensatory hyperinsulinemia in the 15 years since the notion of Syndrome X was introduced, and there are now almost as many components as there are names that have been given to this cluster of abnormalities. Because there is a large body of evidence that the basic abnormality leading to all of these changes is resistance to insulin-mediated glucose disposal, it seems reasonable to suggest that the cluster of abnormalities related to the defect in insulin action be designated as the Insulin Resistance Syndrome.

Malondialdehyde, a Product of Lipid Peroxidation, Is Mutagenic in Human Cells

Malondialdehyde (MDA) is an endogenous genotoxic product of enzymatic and oxygen radical-induced lipid peroxidation whose adducts are known to exist in DNA isolated from healthy human beings. To evaluate the mutagenic potential of MDA in human cells, we reacted MDA with pSP189 shuttle vector DNA and then transfected them into human fibroblasts for replication. MDA induced up to a 15-fold increase in mutation frequency in the supF reporter gene compared with untreated DNA. Sequence analysis revealed that the majority of MDA-induced mutations occurred at GC base pairs. The most frequent mutations were large insertions and deletions, but base pair substitutions were also detected. MDA-induced mutations were completely abolished when the adducted shuttle vector was replicated in cells lacking nucleotide excision repair. MDA induction of large deletions and the apparent requirement for nucleotide excision repair suggested the possible involvement of a DNA interstrand cross-link as a premutagenic lesion. Indeed, MDA formed interstrand cross-links in duplex plasmids and oligonucleotides. Substrates containing the sequence 5'-d(CG) were preferentially cross-linked, consistent with the observation of base pair substitutions in 5'-d(CG) sites in the MDA-induced mutation spectrum. These experiments provide biological and biochemical evidence for the existence of MDA-induced DNA interstrand cross-links that could result from endogenous oxidative stress and likely have potent biological effects.

Oxy radicals, lipid peroxidation and DNA damage

Oxygen radicals react with polyunsaturated fatty acid residues in phospholipids resulting in the production of a plethora of products, many of them reactive toward protein and DNA. One of the most abundant carbonyl products of lipid peroxidation is malondialdehyde (MDA), which also is generated as a side-product of prostaglandin biosynthesis. It reacts with DNA to form adducts to deoxyguanosine, deoxyadenosine, and deoxycytidine. The deoxyguanosine adduct (M 1G) has been detected in liver, white blood cells, colon, pancreas, and breast from healthy human beings at levels ranging from 1 to 120 per 10 8 nucleotides. Random and site-specific mutagenesis experiments indicate that MDA-DNA adducts are mutagenic in bacteria and in mammalian cells. M 1G is highly mutagenic when incorporated into viral genomes then replicated in E. coli. It is repaired by the nucleotide excision repair pathway. Lipid peroxidation appears to be a major source of endogenous DNA damage in humans that may contribute significantly to cancer and other genetic diseases linked to lifestyle and dietary factors.

Insulin sensitivity of glucose disposal and lipolysis: no influence of common genetic variants in IRS-1 and CAPN10.

This study aimed to assess the physiologic relationships between insulin sensitivity of lipolysis and that of glucose disposal and whether two common genetic polymorphisms associated with insulin resistance partially explained the remaining variation. We measured suppression of lipolysis (isotopically [primed-continuous infusion of d5 glycerol] measured glycerol rate of appearance) and glucose disposal during a three-step (n = 24) or standard (n = 57) hyperinsulinaemic euglycaemic clamp in 81 healthy subjects. We also compared insulin sensitivity of lipolysis in carriers (vs. wildtype controls) of the CAPN10 UCSNP43 G/A and IRS-1 Gly972Arg polymorphisms. We observed a significant correlation between insulin sensitivity of glucose disposal and insulin sensitivity of lipolysis ( r = -0.39, p < 0.001) which was retained, albeit weaker, after adjusting for BMI ( r = -0.27, p = 0.002). No significant difference in insulin sensitivity of lipolysis was found between Gly/Gly compared with X/Arg ( IRS-1) and G/G compared with G/A + A/A ( CAPN10) (all p values > 0.15). Insulin sensitivity of lipolysis has a considerable variation in healthy human beings and independently explains about 10% of the variation in insulin sensitivity of glucose disposal (or vice versa). It is possible that mediated through NEFAs, insulin resistance of glucose disposal is secondary to that of lipolysis. Alternatively, the biological variation in insulin sensitivity, to some extent, affects both systems in parallel. Neither of the two putatively insulin resistance-related polymorphisms that were tested contributed measurably to the biological variation of insulin sensitivity of lipolysis.

CD34+ cells in peripheral blood of healthy human beings and allergic subjects: clue to acute and minimal persistent inflammation

There is compelling evidence that hemopoietic precursor cells (HPC) play a crucial role in establishing cellular inflammation in allergic diseases. Increased levels of circulating CD34+ HPC committed to the myeloid lineage have been extensively reported in allergic rhinitis, asthma and eczema, whereas CD34+ cells have been identified within the cellular infiltrates of tissues, at peripheral sites of inflammation. We conducted a pilot study to evaluate CD34+ traffic in the peripheral blood of 22 consecutive patients (13 men and nine women; mean age 28.9 years), independently of treatment. The patients presented rhinitis, asthma, eczema, urticaria and adverse food reactions of suspected allergic origin. Allergic reactions were extrinsic in 18 patients and intrinsic in four. In 12 patients who underwent sublingual specific immunotherapy, CD34+ cells were quantified at enrollment (T0), one year later (T1) and two years later (T2). The severity of symptoms was graded on a five-point scale (0 = absence of symptoms and 4 = severe symptoms). Twenty healthy human subjects (10 men and 10 women; mean age 24.5 years) were evaluated as controls. To obtain information about the total amount of circulating HPC, independently of the lineage commitment (Lin+/-) and the degree of differentiation (CD34bright/dim), we used a modification of the Milan protocol of peripheral blood CD34+ cell estimation. The cells were analyzed using a BD FACScan or FACSCalibur and the results were expressed as the percentage of positive cells. CD34+ cell traffic in the control group was very low since all values were < 0.10 (median value: 0.03 %). Values in the patient group were increased in both extrinsic and intrinsic forms with a median value of 0.25 % (interquartile range: 0.13- 0.33 %). The relationship between CD34+ traffic and the severity score was highly significant (Spearman's rho = 0.954; test of Ho: CD34; independent score: Pr > t = 0.000). The data reported herein suggest that the method employed is effective in assessing acute allergic inflammation, as well as minimal persistent inflammation underlying an asymptomatic clinical condition. Evaluation of CD34bright/dim peripheral traffic, if confirmed by the outcomes of a multicenter study currently being planned together with traditional study of circulating IgE, could be a reliable non-invasive laboratory tool for monitoring allergic inflammation.