Synthetic peptide derived from alpha-fetoprotein inhibits growth of human breast cancer: investigation of the pharmacophore and synthesis optimization

Asynthetic peptide that inhibits the growth of estrogen receptor positive (ER+) human breast cancers, growing as xenografts in mice, has been reported. The cyclic 9-mer peptide, cyclo[EMTOVNOGQ], is derived from alpha-fetoprotein (AFP), a safe, naturally occurring human protein produced during pregnancy, which itself has anti-estrogenic and anti-breast cancer activity. To determine the pharmacophore of the peptide, a series of analogs was prepared using solid-phase peptide synthesis. Analogs were screened in a 1-day bioassay, which assessed their ability to inhibit the estrogen-stimulated growth of uterus in immature mice. Deletion of glutamic acid, Glu1, abolished activity of the peptide, but glutamine (Gln) or asparagine (Asn) could be substituted for Glu1 without loss of activity. Methionine (Met2) was replaced with lysine (Lys) or tyrosine (Tyr) with retention of activity. Substitution of Lys for Met2 in the cyclic molecule resulted in a compound with activity comparable with the Met2-containing cyclic molecule, but with a greater than twofold increase in purity and corresponding increase in yield. This Lys analog demonstrated anti-breast cancer activity equivalent to that of the original Met-containing peptide. Therefore, Met2 is not essential for biologic activity and substitution of Lys is synthetically advantageous. Threonine (Thr3) is a nonessential site, and can be substituted with serine (Ser), valine (Val), or alanine (Ala) without significant loss of activity. Hydroxyproline (Hyp), substituted in place of the naturally occurring prolines (Pro4, Pro7), allowed retention of activity and increased stability of the peptide during storage. Replacement of the first Pro (Pro4) with Ser maintains the activity of the peptide, but substitution of Ser for the second Pro (Pro7) abolishes the activity of the peptide. This suggests that the imino acid at residue 7 is important for conformation of the peptide, and the backbone atoms are part of the pharmacophore, but Pro4 is not essential. Valine (Val5) can be substituted only with branched-chain amino acids (isoleucine, leucine or Thr); replacement by d-valine or Ala resulted in loss of biologic activity. Thus, for this site, the bulky branched side chain is essential. Asparagine (Asn6) is essential for activity. Substitution with Gln or aspartic acid (Asp), resulted in reduction of biologic activity. Removal of glycine (Gly8) resulted in a loss of activity but nonconservative substitutions can be made at this site without a loss of activity indicating that it is not part of the pharmacophore. Cyclization of the peptide is facilitated by addition of Gln9, but this residue does not occur in AFP nor is it necessary for activity. Gln9 can be replaced with Asn, resulting in a molecule with similar activity. These data indicate that the pharmacophore of the peptide includes side chains of Val5 and Asn6 and backbone atoms contributed by Thr3, Val5, Asn6, Hyp7 and Gly8. Met2 and Gln9 can be modified or replaced. Glu1 can be replaced with charged amino acids, and is not likely to be part of the binding site of the peptide. The results of this study provide information that will be helpful in the rational modification of cyclo[EMTOVNOGQ] to yield peptide analogs and peptidomimetics with advantages in synthesis, pharmacologic properties, and biologic activity.

Fast-tracking revisited: routine cardiac surgical patients need minimal intensive care

OBJECTIVE

Following cardiac surgery, patients are transferred from the operating theatre to intensive care. This clinical environment has one nurse per patient and facilities for mechanical ventilation. Patients are kept in this setting until the following day. This practice has been challenged with early extubation of patients. At our institution we have established a fast-track policy including the following features: (1) patient selection; (2) operating list scheduling with fast-track patients first; (3) anaesthetic tailored to early extubation; (4) methodical procedure with warm cardiopulmonary bypass; (5) removal of the arterial line; (6) transfer from intensive care to a separate high dependency unit ('step-down') on the day of operation, where the ratio of nurse to patient is one to three and there are no ventilatory facilities and no invasive monitoring; or (7) to keep these patients on ICU but decrease the nurse to patient ratio.

METHOD

The case notes of 572 patients who predominantly had myocardial revascularisation, undergoing this process from July 1996 to July 2000 at our institution were reviewed.

RESULTS

Mean EUROSCORE for the study group was 1.42. The 30-day mortality rate for the study group was 0.34%, mean intensive care time was 5 h 52 min, mean time to extubation was 3 h 10 min, mean readmission rate to intensive care was 0.34% and mean hospital stay from day of operation (inclusive) was 5.65 days. This process increased our throughput by 14.6% (compared to standard practices).

COMMENT

This study demonstrates that transfer of appropriate patients to a high dependency area from intensive care following cardiac surgery is safe. It allows intensive care beds to be used by more than one patient each day and allows significant cost savings by reducing the nursing ratio per patient.

In situ microcosms to study the impact of heavy metals resuspended by dredging on periphyton in a tropical estuary

Ponggol estuary, located on the northeastern coast of Singapore, is heavily impacted by reclamation, dredging, construction and shipping. Tin, lead, nickel, cadmium, copper and zinc in the particulate and dissolved fraction and in sediments were monitored biweekly in the estuary from July 1999 to June 2000. The concentrations of tin, lead, nickel, cadmium, copper and zinc were observed to range from ND-92 ppm, ND-303 ppm, ND-2818 ppm, ND-74 ppm, ND-1117 ppm and ND-137000 ppm, respectively, in the dissolved, particulate and sediments fractions. Intensive dredging activity occurred during the monitoring period, and this may have led to the resuspension and increased bioavailability of particulate metals. Periphytic algae were established on glass slides and exposed to previously measured environmental levels of heavy metals using in situ estuarine microcosms. The toxicity of heavy metals in various fractions to periphytic algae was assessed from the changes in their chlorophyll a content. Cadmium had the least significant effect followed by lead, zinc, nickel, tin and copper at all concentrations tested. A reduction in periphyton biomass (with respect to controls) of 95-100% was observed for treatments with metals in particulate form. In addition, exposure to contaminated sediments for 3 days significantly decreased chlorophyll a by 90-99% compared to controls. High concentrations of zinc (9893-17240 mg l(-1)), copper (5-11 mg l(-1)) and cadmium (1-1.8 mg l(-1)) recorded in the aqueous phase of treatment microcosms, and attributed to release from the contaminated sediments, could account for the toxicity to periphyton.

Immunohistochemical Demonstration of Leptin in Pancreatic Islets of Non-Obese Diabetic and CD-1 mice: Co-localization in Glucagon Cells and its Attenuation at the Onset of Diabetes

Leptin is a 16 kD polypeptide hormone produced predominantly by white adipose tissue and exerts profound effects on food intake and energy balance. More recent studies have shown extra sites of leptin production in human and rodent tissues and have ascribed additional roles for the hormone, e.g., in immune and reproductive functions. A role for the hormone has also been implicated in insulin-dependent diabetes mellitus in the non-obese diabetic (NOD) mouse. However, whether leptin originates from islet cells of the mouse is not known. Here dual-label immunohistochemistry was employed to examine leptin expression in islet cells, and its distribution and cellular sources in pancreatic sections of female NOD/Ak and CD-1 mice of various ages. For comparison, leptin immunolabelling was examined in adult pancreatic sections from male NOD/Ak CD-1, Balb/c and FVB/N mice and female severe combined immunodeficient CB. 17 mice. Pancreatic tissues from adult female guinea pig, sheep and cattle and neonatal pigs were also studied. Our results show that in the day 1 NOD and CD-1 mice, leptin immunolabelling was observed in selective glucagon cells within the developing islets while at days 15 and 22, it became more intense and co-incident. This pattern of staining was maintained at days 40, 90, 150 and 250. In the female NOD mouse, leptin was absent in intra-islet immune cells. Its expression was variable in islets from male NOD and CD-1 mice. In spontaneously diabetic female NOD mice and following acceleration of diabetes with cyclophosphamide, despite the persistence of strong immunolabelling for glucagon in the re-distributed alpha cells, leptin expression was either absent, diminished or present in only a proportion of alpha cells. The reduction in leptin labelling was often associated with diabetic islets which had insulitis in association with only a small number of residual beta cells. Leptin expression was absent in guinea pig, ovine, bovine and neonatal porcine islet cells, despite the expression of intensely labelled glucagon cells. The present results demonstrate leptin co-localization in glucagon cells of the mouse islet. Its expression diminishes in the presence of inadequate insulin. Leptin produced within the mouse islet may have bi-directional influences on leptin and insulin regulation and may play local functions in islet development and metabolism.

Rat cytochrome P450C24 (CYP24) does not metabolize 1,25-dihydroxyvitamin D2 to calcitroic acid

1alpha-Hydroxy-23 carboxy-24,25,26,27-tetranorvitamin D(3) (calcitroic acid) is known to be the major water-soluble metabolite produced during the deactivation of 1,25-(OH)(2)D(3). This deactivation process is carried out exclusively by the multicatalytic enzyme CYP24 and involves a series of oxidation reactions at C(24) and C(23) leading to side-chain cleavage and, ultimately, formation of the calcitroic acid. Like 1,25-(OH)(2)D(3), 1alpha,25-1,25-(OH)(2)D(2) is also known to undergo side-chain oxidation and side-chain cleavage to form calcitroic acid (Zimmerman et al. [2001]. 1,25-(OH)(2)D(2) differs from 1,25-(OH)(2)D(3) by the presence of a double bond at C(22) and a methyl group at C(24). To date, there have been no studies detailing the participation of CYP24 in the production of calcitroic acid from 1,25-(OH)(2)D(2). We, therefore, studied the metabolism of 1,25-(OH)(2)D(3) and 1,25-(OH)(2)D(2) using a purified rat CYP24 system. Lipid and aqueous-soluble metabolites were prepared for characterization. Aqueous-soluble metabolites were subjected to reverse-phase high-pressure liquid chromatography (HPLC) analysis. As expected, 1,23(OH)(2)-24,25,26,27-tetranor D and calcitroic acid were the major lipid and aqueous-soluble metabolites, respectively, when 1,25-(OH)(2)D(3) was used as substrate. However, when 1,25-(OH)(2)D(2) was used as substrate, 1,24(R),25-(OH)(3)D(2) was the major lipid-soluble metabolite with no evidence for the production of either 1,23(OH)(2)-24,25,26,27-tetranor D or calcitroic acid. Apparently, the CYP24 was able to 24-hydroxylate 1,25-(OH)(2)D(2), but was unable to effect further changes, which would result in side-chain cleavage. These data suggest that the presence of either the double bond at C(22) or the C(24) methyl group impedes the metabolism of 1,25-(OH)(2)D(2) to calcitroic acid by CYP24 and that enzymes other than CYP24 are required to effect this process.

A new method to incorporate age and gender into the criteria for the detection of acute inferior myocardial infarction

Recent studies have shown that younger women are more likely to die during and after hospitalization for acute myocardial infarction (MI) than older women and men of all ages. This may be partly due to incorrect diagnosis or late detection of acute MI in younger women. At high specificity levels (>98%), the sensitivity of the initial ECG to detect acute MI may be as low as 30% when using traditional criteria by both physicians and computerized interpretation programs. This study examines if women of different age groups have a similar ECG presentation to men during acute inferior MI and if the diagnostic accuracies of the initial ECG are comparable. We analyzed chest pain ECGs from Mayo Clinic and Medical College of Wisconsin, which included 1,339 patients with acute inferior MI and 1,169 age-matched controls with noncardiac chest pain. We subdivided all groups by age (below and above 60 years) and compared ECG parameters (ST elevation, ST depression, QRS duration, R-wave amplitude, Q-wave duration and amplitude, QT interval) between genders. For inferior MI patients under age 60, women had lower ST elevations at the J point in lead II than men (57 +/- 91 microV vs. 86 +/- 117 microV, P < .02). This trend was reversed for patients over age 60 (lead a VF: 102 +/- 126 microV vs. 84+/-117 microV, P < .04; Lead III: 130+/-146 microV vs. 103+/-131 microV, P < .007). A neural network method was used to identify the most significant group of ECG parameters for detecting acute MI. An adaptive fuzzy logic method was developed for adapting to the threshold differences among the different gender and age groups. The new algorithm improved the sensitivity of acute inferior MI detection by more than 25% relative to old algorithm, while maintaining the high specificity around 98% for noncardiac chest pain patients.

Acrolein-induced cytotoxicity in cultured human bronchial epithelial cells. Modulation by alpha-tocopherol and ascorbic acid

Acrolein is a highly reactive unsaturated hazardous air pollutant of human health concern, particularly as a component of cigarette smoke. In this study, the mechanisms of acrolein-induced cytotoxicity in human bronchial epithelial cells (HBE1) and the modulating effects of antioxidants were examined. Our results show that acrolein induces a cell death pathway in human bronchial epithelial cells, which retain key features of apoptosis, as indicated by phosphatidylserine (PS) externalization and DNA fragmentation. Acrolein-induced apoptosis was associated with depletion of cellular GSH and intracellular generation of oxidants. Supplementation of cells with either alpha-tocopherol or ascorbic acid was found to strongly inhibit acrolein-induced apoptosis and to prevent the increase in the generation of intracellular oxidants, although GSH depletion was unaffected. Moreover, recovery of cellular GSH levels after acrolein exposure was enhanced following either alpha-tocopherol or ascorbic acid supplementation. The intracellular generation of oxidants following acrolein exposure seems to be an important event triggering the apoptotic response in this model system.

Global burden of cardiovascular diseases: Part II: variations in cardiovascular disease by specific ethnic groups and geographic regions and prevention strategies

This two-part article provides an overview of the global burden of atherothrombotic cardiovascular disease. Part I initially discusses the epidemiological transition which has resulted in a decrease in deaths in childhood due to infections, with a concomitant increase in cardiovascular and other chronic diseases; and then provides estimates of the burden of cardiovascular (CV) diseases with specific focus on the developing countries. Next, we summarize key information on risk factors for cardiovascular disease (CVD) and indicate that their importance may have been underestimated. Then, we describe overarching factors influencing variations in CVD by ethnicity and region and the influence of urbanization. Part II of this article describes the burden of CV disease by specific region or ethnic group, the risk factors of importance, and possible strategies for prevention.

Global burden of cardiovascular diseases: part I: general considerations, the epidemiologic transition, risk factors, and impact of urbanization

This two-part article provides an overview of the global burden of atherothrombotic cardiovascular disease. Part I initially discusses the epidemiologic transition which has resulted in a decrease in deaths in childhood due to infections, with a concomitant increase in cardiovascular and other chronic diseases; and then provides estimates of the burden of cardiovascular (CV) diseases with specific focus on the developing countries. Next, we summarize key information on risk factors for cardiovascular disease (CVD) and indicate that their importance may have been underestimated. Then, we describe overarching factors influencing variations in CVD by ethnicity and region and the influence of urbanization. Part II of this article describes the burden of CV disease by specific region or ethnic group, the risk factors of importance, and possible strategies for prevention.

Pulsatile flow regulates monocyte adhesion to oxidized lipid-induced endothelial cells

Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (ox-PAPC), a component of minimally modified low density lipoprotein, induces monocyte adhesion to endothelial cells. It is not known whether the upstroke slopes of pulsatile flow, defined as shear stress slew rates (tau(r)/tauT)), can regulate monocyte binding to ox-PAPC-treated bovine aortic endothelial cells (BAECs). At 60 cycles per minute, ox-PAPC-treated BAECs were exposed to 3 conditions representing known vascular conditions: (1) high shear stress slew rates (tau(r)/tau(T)=293 dyne. cm(-2). s(-1)), with time-averaged shear stress=50 dyne/cm(2); (2) low shear stress slew rate (tau(r)/tau(t)=71 dyne. cm(-2). s(-1)), with identical time-averaged shear stress; and (3) reversing oscillating flow (0+/-2.6 mm Hg). Reverse transcription-polymerase chain reaction and quantification were performed for monocyte chemoattractant protein-1 (MCP-1) mRNA expression. High tau(r)/tau(t) reduced monocyte binding to ox-PAPC-treated BAECs by 64+/-3.2% compared with static conditions, and low tau(r)/tau(t) reduced monocyte binding by 31+/-3.4%, whereas oscillating flow increased monocyte binding by 22+/-1.7% (P<0.005). High partial tau(r)/tau(t) downregulated MCP-1 expression by 33+/-8%, and low partial tau(r)/tau(t) downregulated MCP-1 expression by 15+/-4%, but oscillating flow upregulated MCP-1 by 13+/-5%. These results suggest that shear stress slew rates regulate monocyte binding by modulating the expression of a potent monocyte chemoattractant.

Inactivation of glutathione S-transferases by nitric oxide-derived oxidants: exploring a role for tyrosine nitration

Reactive intermediates derived from nitric oxide ((*)NO) are thought to play a contributing role in disease states associated with inflammation and infection. We show here that glutathione S-transferases (GSTs), principal enzymes responsible for detoxification of endogenous and exogenous electrophiles, are susceptible to inactivation by reactive nitrogen species (RNS). Treatment of isolated GSTs or rat liver homogenates with either peroxynitrite, the myeloperoxidase/hydrogen peroxide/nitrite system, or tetranitromethane, resulted in loss of GST activity with a concomitant increase in the formation of protein-associated 3-nitrotyrosine (NO(2)Tyr). This inactivation was only partially (<25%) reversible by dithiothreitol, and exposure of GSTs to hydrogen peroxide or S-nitrosoglutathione was only partially inhibitory (<25%) and did not result in protein nitration. Thus, irreversible modifications such as tyrosine nitration may have contributed to GST inactivation by RNS. Since all GSTs contain a critical, highly conserved, active-site tyrosine residue, we postulated that this Tyr residue might present a primary target for nitration by RNS, thus leading to enzyme inactivation. To directly investigate this possibility, we analyzed purified mouse liver GST-mu, following nitration by several RNS, by trypsin digestion, HPLC separation, and matrix-assisted laser desorption/ionization-time of flight analysis, to determine the degree of tyrosine nitration of individual Tyr residues. Indeed, nitration was found to occur preferentially on several tyrosine residues located in and around the GST active site. However, RNS concentrations that resulted in near complete GST inactivation only caused up to 25% nitration of even preferentially targeted tyrosine residues. Hence, nitration of active-site tyrosine residues may contribute to GST inactivation by RNS, but is unlikely to fully account for enzyme inactivation. Overall, our studies illustrate a potential mechanism by which RNS may promote (oxidative) injury by environmental pollutants in association with inflammation.

Essential role of HIV type 1-infected and cyclooxygenase 2-activated macrophages and T cells in HIV type 1 myocarditis

HIV-1 cardiomyopathy has become a major cause of death in AIDS patients, but its pathogenesis is unclear. We used an antigen retrieval technique and immunostaining to investigate the hearts of 15 AIDS patients, of whom 3 had dilated cardiomyopathy. Immunocytochemistry shows infiltration of the left ventricular myocardium with mononuclear cells, ranging from minimal to diagnostic of myocarditis. The infiltrates include macrophages and CD3(+) and CD8(+) T cells. The tight junction protein ZO-1 is disrupted at the site of monocyte-macrophage vascular penetration and the coronary vessels show fibrinogen leakage in the hearts of AIDS patients, but not in the normal heart. A subset of infiltrating macrophages is doubly positive for cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase. HIV-1 peptides gp120 and Nef are expressed in macrophages and T cells, but not in cardiomyocytes. COX-2 is expressed by both gp120-positive and gp120-negative macrophages. The hearts of AIDS patients separate into those showing minimal infiltrates with low COX-2 expression and those with dense infiltrates and high COX-2; all failing hearts are in the latter group. These data suggest that COX-2-activated and HIV-1-infected monocyte-macrophages and T cells play a crucial role in the progression of HIV-1 myocarditis to HIV-1 cardiomyopathy.

Leukocytes infiltrating the pancreatic islets of nonobese diabetic mice are transformed into inactive exiles by combinational anti-cell adhesion therapy

Leukocytes infiltrate the pancreatic islets of nonobese diabetic mice, causing beta-cell destruction and autoimmune Type I diabetes. Here, we completely blocked adoptive transfer of diabetes and reduced spontaneous disease incidence from 71% to 17% by simultaneously administering a combination of antibodies directed against alpha4, beta2, and beta7 integrins and their ligands VCAM-1, MAdCAM-1, and ICAM-1 for 52 and 28 days, respectively. CD4 and CD8 T cells and macrophages were excluded from islets and remained entrapped in a peri-islet location as inactive exiles, no longer expressing normal levels of interferon-gamma, interleukin-4, and iNOS. Only IL-10 expression was retained, which could aid immunosuppression. Infiltrating leukocytes retained a peri-islet location, even 215 days following suspension of antibody treatment, potentially forming a barrier to the entry of active, autoantigen-reactive T cells. Combination treatment was effective against spontaneous disease when administered from 7 days of age but ineffective when initiated late in the prediabetic period (day 40 or 70). Nevertheless, anti-alpha4 subunit mAb monotherapy alone was very effective, reducing insulitis to levels similar to those obtained with combinational antibody treatment, suggesting that alpha4 integrins are major receptors contributing to leukocyte infiltration. Treatment with anti-alpha4 integrin antibody retained some therapeutic benefit when administered from days 7, 40, or 70 of age. The results have implications for the treatment of diabetes and provide a unique insight into the fate of disease-forming leukocytes following anti-CAM therapy.

Gorlin syndrome. A case report

Gorlin's syndrome is a genetic disorder of autosomal dominant inheritance with high penetrance and variable expression. It embraces a constellation of many organs principally affects the skin, skeleton, and endocrine and nervous system. A rare case is reported to illustrate the features of Gorlin's syndrome without the features of basal cell carcinoma and to emphasize the need for early recognition and careful follow up by the dentist prevent severe sequelae.

Characterization of Wnt gene expression in developing and postnatal hair follicles and identification of Wnt5a as a target of Sonic hedgehog in hair follicle morphogenesis

Mutations in WNT effector genes perturb hair follicle morphogenesis, suggesting key roles for WNT proteins in this process. We show that expression of Wnts 10b and 10a is upregulated in placodes at the onset of follicle morphogenesis and in postnatal hair follicles beginning a new cycle of hair growth. The expression of additional Wnt genes is observed in follicles at later stages of differentiation. Among these, we find that Wnt5a is expressed in the developing dermal condensate of wild type but not Sonic hedgehog (Shh)-null embryos, indicating that Wnt5a is a target of SHH in hair follicle morphogenesis. These results identify candidates for several key follicular signals and suggest that WNT and SHH signaling pathways interact to regulate hair follicle morphogenesis.

Skeletal muscle Na currents in mice heterozygous for Six5 deficiency

Myotonic dystrophy results from a trinucleotide repeat expansion between the myotonic dystrophy protein kinase gene (Dmpk), which encodes a serine-threonine protein kinase, and the Six5 gene, which encodes a homeodomain protein. The disease is characterized by late bursts of skeletal muscle Na channel openings, and this is recapitulated in Dmpk -/- and Dmpk +/- murine skeletal muscle. To test whether deficiency of the nearby Six5 gene also affected Na channel gating in murine skeletal muscle, we measured Na currents from cell-attached patches in Six5 +/- mice and age-matched wild-type and Dmpk +/- mice. Late bursts of Na channel activity were defined as an opening probability >10% measured from 10 to 110 ms after depolarization. There was no significant difference in the occurrence of late Na channel bursts in wild-type and Six5 +/- muscle, whereas in Dmpk +/- muscle there was greater than fivefold increase in late bursts (P < 0.001). Compared with wild-type mice, Na current amplitude was unchanged in Six5 +/- muscle, whereas in Dmpk +/- muscle it was 36% reduced (P < 0.05). Thus, since Six5 +/- mice do not exhibit the Na channel gating abnormality of Dmpk deficiency, we conclude that Six5 deficiency does not contribute to the Na channel gating abnormality seen in dystrophia myotonica patients.

Overexpression of Smad2 reveals its concerted action with Smad4 in regulating TGF-beta-mediated epidermal homeostasis

Members of the transforming growth factor-beta (TGF-beta) superfamily are critical regulators for epithelial growth and can alter the differentiation of keratinocytes. Transduction of TGF-beta signaling depends on the phosphorylation and activation of Smad proteins by heteromeric complexes of ligand-specific type I and II receptors. To understand the function of TGF-beta and activin-specific Smad, we generated transgenic mice that overexpress Smad2 in epidermis under the control of keratin 14 promoter. Overexpression of Smad2 increases endogenous Smad4 and TGF-beta 1 expression while heterozygous loss of Smad2 reduces their expression levels, suggesting a concerted action of Smad2 and -4 in regulating TGF-beta signaling during skin development. These transgenic mice have delayed hair growth, underdeveloped ears, and shorter tails. In their skin, there is severe thickening of the epidermis with disorganized epidermal architecture, indistinguishable basement membrane, and dermal fibrosis. These abnormal phenotypes are due to increased proliferation of the basal epidermal cells and abnormalities in the program of keratinocyte differentiation. The ectodermally derived enamel structure is also abnormal. Collectively, our study presents the first in vivo evidence that, by providing an auto-feedback in TGF-beta signaling, Smad2 plays a pivotal role in regulating TGF-beta-mediated epidermal homeostasis.

Dysregulation of the adipoinsular axis -- a mechanism for the pathogenesis of hyperleptinemia and adipogenic diabetes induced by fetal programming

Obesity and its related disorders are the most prevalent health problems in the Western world. Using the paradigm of fetal programming we developed a rodent model which displays the phenotype of obesity and metabolic disorders commonly observed in human populations. We apply maternal undernutrition throughout gestation, generating a nutrient-deprived intrauterine environment to induce fetal programming. Maternal undernutrition results in fetal growth retardation and in significantly decreased body weight at birth. Programmed offspring develop hyperphagia, obesity, hypertension, hyperleptinemia and hyperinsulinism during adult life and postnatal hypercaloric nutrition amplifies the metabolic abnormalities induced by fetal programming. The adipoinsular axis has been proposed as a primary candidate for linking the status of body fat mass to the function of the pancreatic beta-cells. We therefore investigated the relationship between circulating plasma concentrations of leptin and insulin and immunoreactivity in the endocrine pancreas for leptin and leptin receptor (OB-R) in genetically normal rats that were programmed to become obese during adult life. Virgin Wistar rats were time mated and randomly assigned to receive food either available ad libitum (AD group) or at 30% of the ad libitum available intake (UN group). Offspring from UN mothers were significantly smaller at birth than AD offspring (AD 6.13+/-0.04 g, UN 4.02+/-0.03 g, P<0.001). At weaning, offspring were assigned to one of two diets (a standard control diet or a hypercaloric diet consisting of 30% fat) for the remainder of the study. At the time of death (125 days of age), UN offspring had elevated (P<0.005) fasting plasma insulin (AD control 1.417+/-0.15 ng/ml, UN control 2.493+/-0.33 ng/ml, AD hypercaloric 1.70+/-0.17 ng/ml, UN hypercaloric 2.608+/-0.41 ng/ml) and leptin (AD control 8.8+/-1.6 ng/ml, UN control 14.32+/-1.9 ng/ml, AD hypercaloric 15.11+/-1.8 ng/ml, UN hypercaloric 30.18+/-5.3 ng/ml) concentrations, which were further increased (P<0.05) by postnatal hypercaloric nutrition. The elevated plasma insulin and leptin concentrations were paralleled by increased immunolabeling for leptin in the peripheral cells of the pancreatic islets. Dual immunofluorescence histochemistry for somatostatin and leptin revealed that leptin was co-localized in the pancreatic delta-cells. OB-R immunoreactivity was evenly distributed throughout the pancreatic islets and was not changed by programming nor hypercaloric nutrition. Our data suggest that reduced substrate supply during fetal development can trigger permanent dysregulation of the adipoinsular feedback system leading to hyperleptinemia, hyperinsulinism and compensatory leptin production by pancreatic delta-cells in a further attempt to reduce insulin hypersecretion in the progression to adipogenic diabetes.

Long-term follow-up on use of pericardial graft in the surgical management of Peyronie's disease

We have previously reported on the use of Tutoplast cadaveric pericardium as an alternative material for grafting the tunica albugineal defect after Peyronie's plaque excision with satisfactory results in 11 patients. We now review long-term outcomes in this cohort of men. Eleven patients with significant penile curvature interfering with sexual intercourse were evaluated after at least 12 months of conservative therapy. All patients underwent pre-operative evaluation, including penile duplex Doppler ultrasound studies. Chemically processed and gamma-irradiated pericardium (Biodynamics International, Parsippany, NJ) was used to graft the cavernosal defect after surgical excision of the penile plaque. Three patients simultaneously underwent placement of penile prostheses secondary to documented erection problems identified at duplex Doppler ultrasound evaluation. The long-term postoperative complications and erectile function were evaluated with a mean follow-up of 30 months (range 25-35 months). All patients reported resolution of penile curvature allowing for normal sexual function after a mean follow-up of the first 14 months. Thirty months after placement of cadaveric pericardium, the three prosthetic patients still reported excellent sexual function. For the eight patients who did not undergo placement of a prosthesis, three with small to medium plaque size (<2 x 5 cm) continued to do well. The remaining five patients with a large plaque size (>2 x 5 cm) did well initially, but later reported difficulty maintaining erection due to venous leakage, thus they are currently using either a vacuum constriction device or an Actis ring. Three out of these five venous leakage patients had ventral plaques; two had dorsal plaques, one of significant size (4 x 5 cm). We conclude that for those patients who do not undergo placement of a prosthesis, a better long-term outcome is observed when the plaque is small to medium in size (<2 x 5 cm) and dorsally located. Patients with ventral plaque, extreme curvature, or plaque size >4 x 5 cm were more likely to have venoocclusive dysfunction, necessitating further intervention.

Immunoexpression of interleukin-1beta in pancreatic islets of NOD mice during cyclophosphamide-accelerated diabetes: co-localization in macrophages and endocrine cells and its attenuation with oral nicotinamide

During insulin-dependent diabetes mellitus, islet invading immune cells destroy beta cells over a prolonged asymptomatic pre-diabetic period. Cytokines synthesised and secreted by specific immune cells within the islet infiltrate may be crucial effectors of beta cell destruction or protection during the disease. Interleukin-1beta may be a key cytokine which may act in concert with other cytokines in initiating and/or promoting beta cell destruction. We have examined this hypothesis in NOD mice by assessing the intra-islet expression and co-localization of interleukin-1beta at different time-points following cyclophosphamide administration. We have also tested the effects of long-term oral nicotinamide given to NOD mice in suppressing intra-islet expression of the cytokine in this accelerated model. Cyclophosphamide was administered to day 95 female NOD mice. Pancreatic tissues were examined by dual-label confocal immunofluorescence microscopy for the expression and co-localization of interleukin-1beta at days 0, 4, 7, 11 and at onset of diabetes (day 14). Diabetes developed in 7/11 mice 14 days after administration of cyclophosphamide while nicotinamide completely prevented the disease. At day 0, interleukin-1beta immunolabelling was observed in selective intra-islet macrophages, several somatostatin cells and in a few beta cells. However, at day 4, it was seen mostly in somatostatin and some beta cells. At day 7, an increasing number of interleukin-1beta cells were observed within the islets and co-localized to several somatostatin cells, beta cells and macrophages. The mean number of intra-islet interleukin-1beta cells reached a peak at day 11 and was significantly higher than at day 7 (p = 0.05) and at day 14 (onset of diabetes; p = 0.03). At day 11, interleukin-1beta immunolabelling was also present in selective macrophages which co-expressed inducible nitric oxide synthase. At onset of diabetes, some macrophages, residual beta cells and somatostatin cells showed immunolabelling for the cytokine. Exposure of NOD mice to oral nicotinamide was associated with a considerably reduced expression of interleukin-1beta cells within the islet at day 11 (p = 0.002). We conclude that cylophosphamide treatment enhances the expression of interleukin-1beta in selective macrophages, somatostatin and beta cells during the course of the disease. Its expression reaches a maximum immediately prior to onset of diabetes. Interleukin-1beta present in intra-islet macrophages, somatostatin and beta cells may influence its expression by autocrine and paracrine means. Interleukin-1beta expression within islet macrophages may also up-regulate inducible nitric oxide synthase within the same macrophage or adjacent macrophage populations. These intra-islet molecular events may corroborate with other local cytotoxic processes leading to beta cell destruction. Oral nicotinamide may attenuate intra-islet expression of interleukin-1beta and thus inducible nitric oxide synthase during prevention of Type 1 diabetes in this animal model. The expression of interleukin-1beta in specific islet endocrine cell-types shown in this study requires further investigation.

Mitogen-activated protein kinase phosphatase 1 activity is necessary for oxidized phospholipids to induce monocyte chemotactic activity in human aortic endothelial cells

Entrapment and oxidation of low density lipoproteins (LDL) in the sub-endothelial space is a key process in the initiation of atherosclerotic lesion development. Functional changes induced by oxidized lipids in endothelial cells are early events in the pathogenesis of atherosclerosis. Oxidized-l-alpha-1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (ox-PAPC), a major component of minimally modified/oxidized-LDL (MM-LDL) mimics the biological activities assigned to MM-LDL both in vitro in a co-culture model as well as in vivo in mice. We hypothesized that ox-PAPC initiates gene expression changes in endothelial cells that result in enhanced endothelial/monocyte interactions. To analyze the gene expression changes that oxidized lipids induce in endothelial cells, we used a suppression subtractive hybridization procedure to compare mRNA from PAPC-treated human aortic endothelial cells (HAEC) with that of ox-PAPC-treated cells. We report here the identification of a gene, mitogen-activated protein kinase phosphatase 1 (MKP-1), that is rapidly and transiently induced in ox-PAPC-treated HAEC. Inhibition of MKP-1 using either the phosphatase inhibitor sodium orthovanadate or antisense oligonucleotides prevents the accumulation of monocyte chemotactic activity in ox-PAPC-treated HAEC supernatants. Furthermore, we show that decreased monocyte chemotactic activity in HAEC treated with sodium orthovanadate or MKP-1 antisense oligonucleotides is due to decreased MCP-1 protein. Our results implicate a direct role for MKP-1 in ox-PAPC-induced signaling pathways that result in the production of MCP-1 protein by ox-PAPC-treated HAEC.

Automated discrimination between atrial fibrillation and atrial flutter in the resting 12-lead electrocardiogram

Computerized time-domain analysis of the QRST-subtracted 12-lead electrocardiogram (ECG) has been used successfully to determine several atrial activity patterns. These time-domain methods are particularly useful for low-frequency signals such as those originating at the sinus node. However, high frequency atrial fibrillation (AFIB) and atrial flutter (AFL) waves can be better estimated by using spectral methods. In this study, we investigated the use of spectral entropy (SE) and spectral peak detection to distinguish fibrillatory from flutter activity in the QRST-subtracted ECG. In a set of 4,172 cardiologist-overread ECGs, a computerized ECG analysis program (12SL MAC-Rhythm, GE-Marquette Medical Systems, Milwaukee, WI) detected 270 AFIB rhythms and 100 AFL rhythms. Compared to the cardiologist's reading, the AFIB versus AFL miss-classification error was 5.6%. The Fourier Transform was used to estimate the power spectral density of the QRST-subtracted ECG data. Individual lead spectra were then averaged and SE was computed for each of the ECGs originally called AFIB or AFL by the computer program. Additional criteria that included SE, spectral peak frequencies, and time-domain measures of atrial activity were then applied to discriminate between the 2 rhythms. Employing these criteria resulted in a decrease of miss-classification error to 2.5%.

Rapid detection of anti-Helicobacter pylori IgG in urine using immunochromatography

BACKGROUND

Non-invasive methods to detect the presence of H. pylori infection continue to be refined.

AIM

To evaluate a new 20-min immunochromatography method (RAPIRUN H. pylori Antibody) for the presence of anti-H. pylori IgG in urine.

METHODS

We used the (13)C-urea breath test to establish H. pylori status. We evaluated the urine test among 104 subjects including 43 with H. pylori infection confirmed by repeatedly positive urea breath tests and 61 H. pylori-negative subjects with repeatedly negative urea breath tests. Forty-one of the 43 subjects with H. pylori infection had a positive rapid urine test with two false negative tests. There were two false positive tests among the 61 with repeatedly negative urea breath tests. The sensitivity, specificity, positive and negative predictive values for the rapid urine test were 95.3%, 96.7%, 95.3%, and 96.7%, respectively. The kit was easy to use and required no special equipment.

CONCLUSIONS

The rapid immunochromatography method for determination of anti-H. pylori IgG proved to be reliable with excellent sensitivity and specificity and is likely to be useful for both clinical and epidemiological studies.