Changes of serum omentin levels and relationship between omentin and adiponectin concentrations in type 2 diabetes mellitus

BACKGROUND

Omentin has recently been characterized as a potent insulin-sensitizing adipokine, but its pathophysiologic roles in humans remain largely unknown.

OBJECTIVE

To investigate the change of fasting serum omentin levels and evaluate the relationship of omentin with adiponectin in patients with type 2 diabetes mellitus.

DESIGN

35 patients with newly diagnosed type 2 diabetes (T2DM), 35 patients with impaired glucose regulation (IGT) and 35 patients with normal glucose tolerance (NGT) participated in this study. Fasting serum omentin and adiponectin levels were measured by enzyme-linked immunosorbent assay. The relationship between serum omentin, serum adiponectin levels and metabolic parameters was also analyzed.

RESULTS

Fasting serum omentin levels were significantly lower in T2DM and IGT groups than in NGT group (16.75±1.71 vs. 18.62±1.22 vs. 24.60±1.43 ng/ml, all P<0.01). Obesity subjects had significantly lower serum omentin levels than normal body weight subjects ( P<0.01 or P<0.05). Female subjects had moderately higher fasting serum omentin levels than male subjects. Fasting serum adiponectin levels showed a similar variation trend to omentin in T2DM and NGT groups, obesity and normal body weight subjects, female and male subjects. Fasting serum omentin levels were negatively correlated with HOMA-IR and positively correlated with adiponectin. Moreover, HOMA-IR and adiponectin were the independently predictors of fasting serum omentin levels.

CONCLUSIONS

Serum omentin levels possibly play an important role in the pathogenesis of insulin resistance and diabetes. More importantly, there is such a close connection between serum omentin and adiponectin levels that regulation of omentin may be dependent on adiponectin.

Extramammary Paget disease: review of patients seen in a non-melanoma skin cancer clinic

Extramammary Paget disease (EMPD) is a rare skin disease commonly found in the anogenital region. In this study, we aimed to identify EMPD patients seen in the non-melanoma skin cancer clinic at Odette Cancer Centre and to describe the treatments delivered and outcomes achieved. From 2000 to 2009, 14 patients were seen. Initial treatment recommendations included imiquimod and surgical excision, although half the patients required more than one treatment modality, highlighting the difficulty of achieving complete eradication of this disease.

Expression profiling identifies new function of collapsin response mediator protein 4 as a metastasis-suppressor in prostate cancer

Metastasis is the chief cause of mortality from cancer, but the mechanisms leading to metastasis are poorly understood. We used a proteomics approach to screen for metastasis-associated proteins and found that collapsin response mediator protein-4 (CRMP4) expression was inversely associated with the lymph node metastasis of prostate cancer (PCa). Subsequent in vitro and in vivo studies revealed that overexpression of CRMP4 not only suppressed the invasion ability of PCa cells, but also strongly inhibited tumor metastasis in an animal model. Furthermore, methylation of a CpG island within the promoter region of the CRMP4 gene is responsible for downregulation of CRMP4 expression. Thus, in this study, we show new function of CRMP4 as a metastasis-suppressor in PCa. The findings provide new mechanistic insights into metastasis and therapeutic potential for this most common male cancer.

Self-complementary AAV-mediated gene therapy restores cone function and prevents cone degeneration in two models of Rpe65 deficiency

To test whether fast-acting, self-complimentary (sc), adeno-associated virus-mediated RPE65 expression prevents cone degeneration and/or restores cone function, we studied two mouse lines: the Rpe65-deficient rd12 mouse and the Rpe65-deficient, rhodopsin null ('that is, cone function-only') Rpe65(-/-)::Rho(-/-) mouse. scAAV5 expressing RPE65 was injected subretinally into one eye of rd12 and Rpe65(-/-)::Rho(-/-) mice at postnatal day 14 (P14). Contralateral rd12 eyes were injected later, at P35. Rd12 behavioral testing revealed that rod vision loss was prevented with either P14 or P35 treatment, whereas cone vision was only detected after P14 treatment. Consistent with this observation, P35 treatment only restored rod electroretinogram (ERG) signals, a result likely due to reduced cone densities at this time point. For Rpe65(-/-)::Rho(-/-) mice in which there is no confounding rod contribution to the ERG signal, cone cells and cone-mediated ERGs were also maintained with treatment at P14. This work establishes that a self-complimentary AAV5 vector can restore substantial visual function in two genetically distinct models of Rpe65 deficiency within 4 days of treatment. In addition, this therapy prevents cone degeneration but only if administered before extensive cone degeneration, thus supporting continuation of current Leber's congenital amaurosis-2 clinical trials with an added emphasis on cone subtype analysis and early intervention.

Comparison of the MMSE and RUDAS cognitive screening tools in an elderly inpatient population in everyday clinical use

We compared test score and performance times of Folstein's Mini Mental State Examination (MMSE) and the Rowland Universal Dementia Assessment Scale (RUDAS). Forty-six patients were recruited. The mean score was 20.6 for the MMSE and 20.5 for the RUDAS. Linear regression analysis revealed an r value of 0.83 (P < 0.05). The mean performance time was 9.4 min for both the MMSE and the RUDAS. Patient satisfaction was similar for both tests. Surveyed clinicians preferred the MMSE because of greater familiarity. We concluded that the RUDAS correlates well with the MMSE and is no more time-consuming to perform. It has good clinical utility as a cognitive screening tool.

Broken bones and fractures - an audit of patients' perceptions

INTRODUCTION

'Have I got a fracture or a break doctor?' remains a commonly posed question in fracture clinics, suggesting that patients frequently feel a 'fracture' and a 'break' are two separate entities. This apparent misconception amongst fracture clinic patients may result in confusion and occasionally anger that doctors appear to have inconsistent views on the severity of their injury. Compliance and outcome of patient care can also be affected by poor communication.

PATIENTS AND METHODS

Our questionnaire-based study was conducted in two stages. The initial objective was to establish whether this misconception surrounding the words 'fracture' and 'break' is commonly held amongst our out-patient trauma patients. The second stage of the audit was to determine whether a patient information leaflet on fractures/broken bones could help reduce this misconception.

RESULTS

The preliminary audit involving 50 new patients attending our fracture clinic showed that 84% thought there was a difference between a 'fracture' and a 'break', with 68% believing a 'break' to be worse than a 'fracture'. Following the introduction of an information leaflet, a re-audit of 61 new patients took place. This time 67% felt there was a difference between a 'fracture' and a 'break', with 65% believing a 'break' to be worse than a 'fracture'. Only 21% had read the supplied information leaflet, and 69% of those still believed there was a difference between a 'fracture' and a 'break'.

CONCLUSIONS

The majority of patients believed that there was a difference between a 'fracture' and a 'break'. Access to information leaflets did not appear to alter this misconception. Verbal communication and explanation may be more beneficial and practical than visual aids and leaflets in overcoming this problem.

Anticancer Activity of 5-Benzylidene-2-Phenylimino-1, 3-Thiazolidin-4-one (BPT) Analogs

We recently identified two compounds of 5-benzylidene-2-phenylimino-1,3-thiazolidin-4-one (BPT) analog, 5-(4-methylbenzylidene)-2-phenylamino-1,3-thiazolidin-4-one (MMPT) and 5-(2,4-dihydroxybenzylidene)-2-phenylimino-1,3-thiazolidin-4-one (DBPT), that can effectively induce apoptosis in cancer cells but not in normal cells, independently of P-glycoprotein status. To further investigate the antitumor activity of BPT analogs, we obtained 18 commercially available analogs of BPT and synthesized 7 analogs in our lab, and analyzed their antitumor activity in various cancer cells, including paclitaxel- and vinorelbine-sensitive and -resistant human lung cancer cells. Two of the compounds were more potent than MMPT or DBPT in induction of apoptosis in certain cancer cell lines and remained tumor selective. Seven compounds did not induce any cytotoxic effects in any of the cell lines tested at the highest concentration tested (31 microM). The other compounds induced cytotoxic effects in some cancer cells but not in others or were less potent than MMPT and DBPT. Cell uptake studies showed that analogs that effectively induced cell killing in paclitaxel- and vinorelbine-resistant cells could be taken up easily by those cells despite their high levels of P-glycoprotein expression. These data further demonstrate that thiazolidinone analogs are not P-glycoprotein substrates and could be useful for treatment of P-glycoprotein overexpressing refractory cancers.

NMDA receptor activation induces mitochondrial dysfunction, oxidative stress and apoptosis in cultured neonatal rat cardiomyocytes

Glutamate is a well-characterized excitatory neurotransmitter in the central nervous system (CNS). Recently, glutamate receptors (GluRs) were also found in peripheral tissues, including the heart. However, the function of GluRs in peripheral organs remains poorly understood. In the present study, we found that N-methyl-D-aspartate (NMDA) could increase intracellular calcium ([Ca(2+)]i) level in a dose-dependent manner in cultured neonatal rat cardiomyocytes. NMDA at 10(-4) M increased the levels of reactive oxygen species (ROS), cytosolic cytochrome c (cyto c), and 17-kDa caspase-3, but depolarized mitochondrial membrane potential, leading to cardiomyocyte apoptosis. In addition, NMDA treatment induced an increase in bax mRNA but a decrease in bcl-2 mRNA expression in the cardiomyocytes. The above effects of NMDA were blocked by the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801), and by ROS scavengers glutathione (GSH) and N-acetylcystein (NAC). These results suggest that stimulation of NMDA receptor in the cardiomyocyte may lead to apoptosis via a Ca(2+), ROS, and caspase-3 mediated pathway. These findings suggest that NMDA receptor may play an important role in myocardial pathogenesis.

Light-induced transient ion flux responses from maize leaves and their association with leaf growth and photosynthesis

Net fluxes of H+, K+ and Ca2+ ions from maize (Zea mays L.) isolated leaf segments were measured non-invasively using ion-selective vibrating microelectrodes (the MIFE technique). Leaf segments were isolated from the blade base, containing actively elongating cells (basal segments), and from non-growing tip regions (tip segments). Ion fluxes were measured in response to bright white light (2600 micromoles m-2 s-1) from either the leaf segments or the underlying mesophyll (after stripping the epidermis). Fluxes measured from the mesophyll showed no significant difference between basal and tip regions. In leaf segments (epidermis attached), light-induced flux kinetics of all ions measured (H+, Ca2+ and K+) were strikingly different between the two regions. It appears that epidermal K+ fluxes are required to drive leaf expansion growth, whereas in the mesophyll light-induced K+ flux changes are likely to play a charge balancing role. Light-stimulated Ca2+ influx was not directly attributable either to leaf photosynthetic performance or to leaf expansion growth. It is concluded that light-induced ion flux changes are associated with both leaf growth and photosynthesis.

Physiological aspects of vetiver grass for rehabilitation in abandoned metalliferous mine wastes

Physiological aspects of why vetiver grass (Vetiveria zizanioides L.) can be tolerant to heavy metals and be used as an alternative method for rehabilitation of abandoned metalliferous mine wastelands have been investigated. The results showed that high proportions of lead and zinc (Pb/Zn) tailing greatly inhibited the leaf growth, dry matter accumulation, and photosynthesis of leaves, but stimulated the accumulation of proline and abscisic acid (ABA), and enhanced the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), implying that different mechanisms to detoxify active oxygen species (AOS) existed in different parts of plants. Physiological responses to heavy metal treatments differed greatly between roots and shoots. Nitrogen fertilizer application could greatly alleviate the adverse effects of high proportions of Pb/Zn tailing on vetiver grass growth.

Alfentanil infusion as a component of intravenous anaesthesia for coronary artery bypass surgery with "fast-track" recovery

Alfentanil and propofol total intravenous anaesthesia was assessed in 25 patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass (CPB). A manually controlled alfentanil infusion, calculated from estimated lean body mass and published pharmacokinetic data, was effective in achieving target plasma concentrations, while the "Diprifusor" system was used to vary propofol target concentrations according to changes in haemodynamics and anaesthetic requirement. The effects of CPB on alfentanil plasma concentrations were offset by changes in protein binding and free-fraction of the drug. With the use of only two target plasma concentrations for alfentanil (changed after CPB), a pre-determined infusion profile ensured effective plasma concentrations during surgery and concentrations unlikely to inhibit extubation within six hours of sternal closure.

Subluminous phase velocity of a focused laser beam and vacuum laser acceleration

It has been found that for a focused laser beam propagating in free space, there exists, surrounding the laser beam axis, a subluminous wave phase velocity region. Relativistic electrons injected into this region can be trapped in the acceleration phase and remain in phase with the laser field for sufficiently long times, thereby receiving considerable energy from the field. Optics placed near the laser focus are not necessary, thus allowing high intensities and large energy gains. Important features of this process are examined via test particle simulations. The resulting energy gains are in agreement with theoretical estimates based on acceleration by the axial laser field.

Effects of alcohol on blood pressure and production of vascular aldosterone and corticosterone

AIMS

The aims of this study were to search for the role of alcohol in blood pressure regulation in rats and to investigate the effects of alcohol on the production of vascular aldosterone and corticosterone.

METHODS

Male Wistar rats received alcohol 0.7 g x kg(-1) x day(-1) (alcohol-treated group 1) or 1.4 g x kg(-1) x day(-1) (alcohol-treated group 2) or 2.1 g x kg(-1) x day(-1) (alcohol-treated group 3), orally, for 3 months, and blood pressure was monitored by a pressure transducer. Systolic blood pressure increased in Wistar rats treated with alcohol compared to control rats. Mesenteric artery perfusion ex vivo was performed and pressor responses to norepinephrine were determined. The pressor responses to norepinephrine in mesenteric arteries treated with alcohol were significantly increased. The perfusate from the mesenteric arteries was collected and applied to a Sep-Pak C 18 cartridge column for reverse-phase high-performance liquid chromatography and aldosterone and corticosterone levels were determined by radioimmunoassay, aldosterone was decreased but corticosterone was increased in the perfusate from arteries treated with alcohol.

RESULTS

Reverse transcriptase polymerase chain reaction showed that alcohol inhibited the expression of 11beta-HSD2 and CYP11B2 mRNA in mesenteric arteries.

CONCLUSIONS

These results reveal that alcohol is able to induce hypertension and provide evidence that alcohol inhibits the transcriptions of both 11beta-HSD2 and CYP11B2 in the vasculature, leading to lower aldosterone and higher corticosterone production in vessels, and increased vasoconstrictor responses to norepinephrine.

Clinicopathological report of retinitis pigmentosa with vitamin E deficiency caused by mutation of the alpha-tocopherol transfer protein gene

PURPOSE

To discuss the clinicopathological findings in a patient with retinitis pigmentosa (RP) accompanied by a vitamin E deficiency caused by an H101Q mutation in the alpha-tocopherol transfer protein (alpha-TTP) gene.

CASE

The clinical course of this patient was followed by conventional ophthalmological examinations over a 3-year period. After the patient died from pancreatic cancer, the eyes were obtained, and examined by light and electron microscopy.

OBSERVATIONS

The patient complained of night blindness subsequent to adult-onset ataxia, although the ataxia was very mild. His visual acuity was 0.6 OU, and ophthalmoscopy revealed RP sine pigmento. Ring scotomas were detected, and the electroretinography, electro-oculography, and dark-adaptation were altered. Fluorescein angiography showed granular hyperfluorescence around the macula. No progression of the visual and neurological symptoms was observed during the 10 years he was taking oral vitamin E. Histopathological examination revealed the loss of the outer and inner segments of the photoreceptors in the area corresponding to the ring scotoma, as well as a disorganization and shortening of the outer segments in the peripheral retina.

CONCLUSIONS

We conclude that the clinical and pathological findings in the eyes of this patient having RP with vitamin E deficiency caused by an H101Q mutation are similar to those of common autosomal recessive RP. However, special attention is required in making a diagnosis of RP with vitamin E deficiency because RP with vitamin E deficiency is medically treatable. The mild Friedreich-type ataxia accompanying the RP may be helpful in identifying this disease.

Cloning and characterization of Ginkgo biloba levopimaradiene synthase which catalyzes the first committed step in ginkgolide biosynthesis

Levopimaradiene synthase, which catalyzes the initial cyclization step in ginkgolide biosynthesis, was cloned and functionally characterized. A Ginkgo biloba cDNA library was prepared from seedling roots and a probe was amplified using primers corresponding to conserved gymnosperm terpene synthase sequences. Colony hybridization and rapid amplification of cDNA ends yielded a full-length clone encoding a predicted protein (873 amino acids, 100,289 Da) similar to known gymnosperm diterpene synthases. The sequence includes a putative N-terminal plastid transit peptide and three aspartate-rich regions. The full-length protein expressed in Escherichia coli cyclized geranylgeranyl diphosphate to levopimaradiene, which was identical to a synthetic standard by GC/MS analysis. Removing 60 or 79 N-terminal residues increased levopimaradiene production, but a 128-residue N-terminal deletion lacked detectable activity. This is the first cloned ginkgolide biosynthetic gene and the first in vitro observation of an isolated ginkgolide biosynthetic enzyme.

Sterols in blood of normal and Smith-Lemli-Opitz subjects

Smith-Lemli-Opitz syndrome (SLOS) is a hereditary disorder in which a defective gene encoding 7-dehydrocholesterol reductase causes the accumulation of noncholesterol sterols, such as 7- and 8-dehydrocholesterol. Using rigorous analytical methods in conjunction with a large collection of authentic standards, we unequivocally identified numerous noncholesterol sterols in 6 normal and 17 SLOS blood samples. Plasma or erythrocytes were saponified under oxygen-free conditions, followed by multiple chromatographic separations. Individual sterols were identified and quantitated by high performance liquid chromatography (HPLC), Ag(+)-HPLC, gas chromatography (GC), GC-mass spectrometry, and nuclear magnetic resonance. As a percentage of total sterol content, the major C(27) sterols observed in the SLOS blood samples were cholesterol (12;-98%), 7-dehydrocholesterol (0.4;-44%), 8-dehydrocholesterol (0.5;-22%), and cholesta-5,7,9(11)-trien-3beta-ol (0.02;-5%), whereas the normal blood samples contained <0.03% each of the three noncholesterol sterols. SLOS and normal blood contained similar amounts of lathosterol (0.05;-0.6%) and cholestanol (0.1;-0.4%) and approximately 0.003;-0.1% each of the Delta(8), Delta(8(14)), Delta(5,8(14)), Delta(5,24), Delta(6,8), Delta(6,8(14)), and Delta(7,24) sterols. The results are consistent with the hypothesis that the Delta(8(14)) sterol is an intermediate of cholesterol synthesis and indicate the existence of undescribed aberrant pathways that may explain the formation of the Delta(5,7,9(11)) sterol. 19-Norcholesta-5,7,9-trien-3beta-ol was absent in both SLOS and normal blood, although it was routinely observed as a GC artifact in fractions containing 8-dehydrocholesterol. The overall findings advance the understanding of SLOS and provide a methodological model for studying other metabolic disorders of cholesterol synthesis.

Pharmacokinetics and pharmacodynamic effects of 5-fluorouracil given as a one-hour intravenous infusion

PURPOSE

Clinical toxicity associated with 5-fluorouracil (5-FU) is related to the area under the plasma concentration-time curve (AUC). Recently, short-term infusions of 5-FU given over 30 or 60 min have been substituted for conventional "bolus" 5-FU given over 3-5 min in randomized clinical trials, but there are only limited pharmacokinetic data for these altered infusion durations. We therefore wished to determine the pharmacokinetics and toxicity associated with 5-FU given as a 1-h intravenous (i.v.) infusion.

METHODS

A group of 22 adults with advanced gastrointestinal tract cancers and no prior systemic chemotherapy for advanced disease received interferon alpha-2a (5 MU/m2 s.c., days 1-7), leucovorin (500 mg/m2 i.v. over 30 min, days 2-6) and 5-FU (370 mg/m2 i.v. over 1 h, days 2-6). The doses of 5-FU and interferon-alpha were adjusted according to individual tolerance. The pharmacokinetics and clinical toxicity were retrospectively compared with patients receiving the same regimen under the same treatment guidelines except that 5-FU was given over 5 min.

RESULTS

The regimen was well tolerated, and 41% of the patients tolerated 5-FU dose escalations to 425-560 mg/m2 per day. Grade 3 or worse diarrhea and fatigue ultimately occurred in 14% of the patients each. Granulocytopenia, mucositis, and diarrhea appeared to be appreciably milder in the present trial compared with our prior phase II experience in colorectal cancer. The peak 5-FU plasma levels and AUC with 370 mg/m2 5-FU given over 1 h were 7.3-fold and 2.4-fold lower than previously measured in 31 patients who received 5-FU over 5 min.

CONCLUSION

Increasing the length of 5-FU infusion to 1 h seemed to substantially reduce the clinical toxicity with this modulated 5-FU regimen, likely due to markedly lower peak 5-FU plasma levels and AUC. Changes in the duration of a short infusion of 5-FU clearly affects the clinical toxicity, but raises the concern of a potentially adverse impact on its antitumor activity. These results suggest the importance of including precise guidelines concerning the time over which 5-FU is given in clinical trials. Having a specified duration of 5-FU infusion is also important if 5-FU dose escalation is considered.

Degradation of a fluoropyridinyl drug in capsule formulation: degradant identification, proposed degradation mechanism, and formulation optimization

The purpose of this paper was to investigate the degradation chemistry of a fluoropyridinyl drug candidate in capsule formulation and to optimize the formulation based on a proposed degradation mechanism. Small developmental batches of capsules were made by tituration of drug substance and excipients using a mortar and pestle, followed by manual encapsulation. Degradants were identified by LC-MS/MS and LC-photodiode array detector (PDA) and were monitored by LC-ultraviolet detector (UVD) during stability studies. It was found that the drug could undergo a nucleophilic substitution reaction in which hydroxyl groups replace the fluorine substituents on the pyridine rings. The initial degradation rate is independent of the drug concentration but dependent on the temperature, the pH of the microenvironment, and the excipient type. On the basis of these experimental results, a nucleophilic substitution reaction mechanism for the degradation was proposed and a successful capsule formulation was developed.

[Effect of unprepared and prepared "he zi" on contraction of isolated trachea smooth muscle in rabbits]

Isolated trachea smooth muscle in rabbits induced by Ach or KCl was adopted to study the effect of unprepared and prepared "He Zi". The results showed that unprepared "He Zi" couldn't affect the contraction of isolated trachea smooth muscle in rabbit induced by Ach or KCl, and that prepared "He Zi" couldn't affect the contraction of isolated trachea smooth muscle in rabbit induced by KCl. The results also showed that prepared "He Zi" could significantly inhibit the contraction induced by Ach. The inhibition effect may not be associated with cGMP, adrenergic receptor, and release of NO and prostaglandin, and was epithelium independent. Maybe the different content of tannic acid contributed to the different effect between unprepared and prepared "He Zi".

Blue light-induced apoptosis in cultured retinal pigment epithelium cells of the rat

BACKGROUND

We previously demonstrated that phagosome-free retinal pigment epithelium (RPE) cells in culture can be damaged directly by blue light (wavelength 440+/-10 nm) as observed by electron microscope. A low intensity (1.0 mW/cm2) of light induced only swelling of mitochondria, while a high intensity (4.0 mW/cm2) induced necrosis in the RPE. The aim of the present study was to investigate what intensity of blue light could induce apoptosis in cultured phagosome-free RPE.

METHODS

Primary cultured RPE cells, harvested from Long-Evans rats, that contained no phagosomes were exposed to a cool blue light (wavelength 440+/-10 nm). After exposure, transmission electron microscopy (TEM) and TdT-mediated dUTP nick-end labeling (TUNEL) staining were used to detect apoptosis in the RPE cells. To assess the relationship of oxidation to apoptosis by blue light, we added N-acetylcysteine (NAC) as a free radical scavenger and investigated its inhibitory effect on apoptosis.

RESULTS

In RPE cells exposed to blue light of 2.7 mW/cm2 for 24 h, apoptotic bodies were found by TEM. In RPE cells exposed to blue light of 2.0 mW/cm2 for 60 h, apoptotic bodies, nuclear condensation and nuclear segmentation were observed by TEM and some RPE cells showed positive TUNEL staining. When 30 mM of NAC was added, TUNEL staining was negative.

CONCLUSION

Our findings demonstrate that apoptotic cell death is induced by blue light exposure in cultured RPE cells in vitro. The findings of our previous experiments and those of the present study suggest that a higher intensity of blue light could induce necrosis, and moderately intense blue light could induce non-necrotic cell death or apoptosis, in RPE cells. Furthermore, it is suggested that blue light caused cell death by a free-radical-associated mechanism.

Do antenatal corticosteroids help in the setting of preterm rupture of membranes?

OBJECTIVE

It is now accepted that corticosteroid administration before preterm delivery reduces neonatal mortality and morbidity. However, corticosteroid use in the setting of rupture of membranes remains controversial.

STUDY DESIGN

We reviewed data from the first and largest randomized trial in this area and included them in a new meta-analysis.

RESULTS

Data from 318 women with rupture of membranes in the Auckland Trial showed that there was a trend toward reduction of the risk of respiratory distress syndrome with corticosteroids but that this trend did not reach statistical significance. There was little effect on the risks of neonatal death, intraventricular hemorrhage, and fetal, neonatal, or maternal infection. Combined data from 15 controlled trials involving >1400 women with rupture of membranes confirmed that corticosteroids reduce the risks of respiratory distress syndrome (relative risk, 0.56; 95% confidence interval, 0.46-0.70), intraventricular hemorrhage (relative risk, 0.47; 95% confidence interval, 0.31-0.70), and necrotizing enterocolitis (relative risk, 0.21; 95% confidence interval, 0.05-0.82). They also may reduce the risk of neonatal death (relative risk, 0.68; 95% confidence interval, 0.43-1.07). They do not appear to increase the risk of infection in either mother (relative risk, 0.86; 95% confidence interval, 0.61-1.20) or baby (relative risk, 1.05; 95% confidence interval, 0.66-1.68). The duration of rupture of membranes does not alter these outcomes.

CONCLUSION

The available data indicate that corticosteroid administration is beneficial in the setting of rupture of membranes. In our opinion further trials to address this question cannot be justified.

[Study on the role of human papillomavirus in carcinogenesis of oral papillomas by in situ hybridization]

OBJECTIVE

To explore the role of human papillomavirus (HPV) infection on carcinogenesis of oral squamous cell papillomas (SCP).

METHODS

By using digoxin labelled HPV 6/11 and HPV 16/18 probes, through hybridization in situ technique, the HPV DNA sequence in 30 cases of oral SCP were detected.

RESULTS

Among them, 16 cases (53.3%) were positive for HPV 6/11 DNA. None of cases of SCP were positive for HPV 16/18 DNA.

CONCLUSION

Our results show that the frequent finding of HPV 6/11 DNA in oral SCP had close association between oral papillomas and HPV 6/11 infection.

High glucose inhibits glucose-6-phosphate dehydrogenase via cAMP in aortic endothelial cells

Recent studies have shown that hyperglycemia is a principal cause of cellular damage in patients with diabetes mellitus. A major consequence of hyperglycemia is increased oxidative stress. Glucose-6-phosphate dehydrogenase (G6PD) plays an essential role in the regulation of oxidative stress by primarily regulating NADPH, the main intracellular reductant. In this paper we show that increased glucose (10-25 mm) caused inhibition of G6PD resulting in decreased NADPH levels in bovine aortic endothelial cells (BAEC). Inhibition was seen within 15 min. High glucose-induced inhibition of G6PD predisposed cells to cell death. High glucose via increased activity of adenylate cyclase also stimulated an increase in cAMP levels in BAEC. Agents that increased cAMP caused a decrease in G6PD activity. Inhibition of cAMP-dependent protein kinase A ameliorated the high glucose-induced inhibition of G6PD. Finally, high glucose stimulated phosphorylation of G6PD. These results suggest that, in BAEC, high glucose stimulated increased cAMP, which led to increased protein kinase A activity, phosphorylation of G6PD, and inhibition of G6PD activity. We conclude that these changes in G6PD activity play an important role in high glucose-induced cell damage/death.

Expression of functional soluble human alpha-globin chains of hemoglobin in bacteria

Individual, soluble human alpha-globin chains were expressed in bacteria with exogenous heme and methionine aminopeptidase. The yields of soluble alpha chains in bacteria were comparable to those of recombinant non-alpha chains expressed under the same conditions. Molecular mass and gel-filtration properties of purified recombinant alpha chains were the same as those of authentic human alpha chains. Biochemical and biophysical properties of isolated alpha chains were identical to those of native human alpha chains as assessed by UV/vis, circular dichroism (CD), and nuclear magnetic resonance (NMR) spectroscopy which contrasts with previous results of refolded precipitated alpha chains made in the presence of heme in vitro (M. T. Sanna et al., J. Biol. Chem. 272, 3478-3486, 1997). Mixtures of purified, soluble recombinant alpha-globin and native beta-globin chains formed heterotetramers in vitro, and oxygen- and CO-binding properties as well as the heme environment of the assembled tetramers were experimentally indistinguishable from those of native human Hb A. UV/vis, CD, and NMR spectra of assembled Hb A were also the same as those of human Hb A. These results indicate that individual expressed alpha chains are stable in bacteria and fold properly in vivo and that they then can assemble with free beta chains to form hemoglobin heterotetramers in vivo as well as in vitro.

Steric bulk at cycloartenol synthase position 481 influences cyclization and deprotonation

Cycloartenol synthase converts oxidosqualene to the pentacyclic sterol precursor cycloartenol. An Arabidopsis thaliana cycloartenol synthase Ile481Val mutant was previously shown to produce lanosterol and parkeol in addition to its native product cycloartenol. Experiments are described here to construct Phe, Leu, Ala, and Gly mutants at position 481 and to determine their cyclization product profiles. The Phe mutant was inactive, and the Leu mutant produced cycloartenol and parkeol. The Ala and Gly mutants formed lanosterol, cycloartenol, parkeol, achilleol A, and camelliol C. Monocycles comprise most of the Gly mutant product, showing that an alternate cyclization route can be made the major pathway by a single nonpolar mutation.

Kinetics and plasma concentrations of 26-hydroxycholesterol in baboons

26-Hydroxycholesterol (26OHC), a major oxysterol in human blood, is believed to play an important role in reverse cholesterol transport, bile acid formation, and regulation of various cellular processes. Using isotope dilution mass spectrometry, we measured plasma 26OHC concentrations in baboons fed either a high cholesterol/saturated fat (HC-SF) or normal chow diet. Plasma 26OHC levels in baboons were comparable to those reported for humans and were positively correlated with plasma cholesterol concentrations. Animals on the HC-SF diet had significantly higher 26OHC levels (0.274+/-0.058 microM, mean+/-S.D.) than those on the chow diet (0.156+/-0.046 microM). In separate experiments, [(3)H]26OHC was injected into four tethered baboons, and multiple blood samples drawn over a 1-h period were analyzed for [(3)H]26OHC and 26OHC. Fitting the specific radioactivity data to a two-pool compartmental model indicated a rapidly turning over plasma compartment (t(1/2) 2.9-6.0 min) and a second compartment with slow turnover (t(1/2) 76-333 min). The calculated 26OHC production rate was 2.5 micromol/kg body weight/day. Assuming all 26OHC is converted to bile acids, the 26OHC production rate corresponds to about 10% of total bile acid production in adult baboons. These results indicate that rapid turnover of plasma 26OHC at submicromolar concentrations could significantly contribute to bile acid synthesis.

Lung function following cardiac surgery is not affected by postoperative ventilation time

We investigated the effect of postoperative ventilation time on lung function following cardiac surgery. A prospective observational study of 100 elective patients. Anaesthetic technique and postoperative ventilation times reflected the routine of participating anaesthetists. Group I (n = 29) patients were extubated prior to leaving the operating room, Group II (n = 37) within 8 hours and Group III (n = 28) after 8 hours. Oxygen saturation on air, spirometry and chest x-rays were performed preoperatively and on postoperative days 2, 3 and 4. No demographic differences were detected between groups. There was no mortality, perioperative myocardial infarction or reintubation in any group. Lung function significantly declined following surgery in all groups (p<0.0001) for all endpoints, but was not different between groups. Chest x-ray changes were common in all groups but not significantly different between groups. Immediate extubation does not worsen lung function compared to early or late extubation.

Determination of in vitro permeability of drug candidates through a caco-2 cell monolayer by liquid chromatography/tandem mass spectrometry

Studying the permeability of compounds across a Caco-2 cell monolayer is an established in vitro model to screen for oral absorption and to evaluate the mechanism of transport. This assay can also be used to evaluate compounds as potential P-glycoprotein substrates and/or inhibitors. The traditional methods of sample analysis (high-performance liquid chromatography (HPLC) with a UV or fluorescence detector) limit the throughput and sensitivity of this assay. Data are presented here describing the use of liquid chromatography/tandem mass spectrometry (LC/MS/MS) for the analysis of samples derived from the Caco-2 cell studies. During the analysis an automatic switching valve was used to divert the flow from the HPLC column to waste for the first minute, preventing the early eluting salts from entering and contaminating the LC/MS interface. This approach allows the rapid and accurate determination of drug transport across the Caco-2 cell monolayer. The high sensitivity and specificity of LC/MS/MS make this technique an ideal candidate for the low concentration and high throughput routine analysis of Caco-2 cell solutions, especially if multiple compounds are administered and analyzed simultaneously. Thus, the use of LC/MS/MS will increase the value of the Caco-2 cell assay as an in vitro screening tool.

Synthesis of [3alpha-3H]cholesta-5,8-dien-3beta-ol and tritium-labeled forms of other sterols of potential importance in the Smith-Lemli-Optiz syndrome

Five unsaturated sterols relevant to the Smith-Lemli-Opitz syndrome have been prepared in high radiochemical purity with a tritium label at the 3alpha position. Swern oxidation of cholesta-5,8-dien-3beta-ol and other unlabeled C27 sterols afforded the corresponding 3-ketosteroids, and reduction with tritiated NaBH4 gave the desired 3alpha-3H sterols, with double bonds at the delta(5,8), delta(5,8(14)), delta(6,8), delta(6,8(14)), and delta8 positions. High radiochemical purity of the tritiated sterols was demonstrated by normal phase, reversed phase, and silver-ion (Ag+) high-performance liquid chromatography (HPLC). In the course of this work, we developed a medium-pressure variant of Ag+-HPLC for purifying radiolabeled samples, documented significant isotopic fractionation of the 3alpha-tritiated sterols and their acetates on Ag+-HPLC, and discovered unexpected effects of a delta(8(14)) bond on the conformation of 3-keto-delta5-steroids. The synthetic and analytical methodologies described herein should provide a sound basis for investigating the origin and metabolism of sterols involved in the Smith-Lemli-Opitz syndrome and in late stages of cholesterol biosynthesis.

[Effects of autogenous periodontal ligament cell transplantation on periodontal tissue regeneration in dogs]

OBJECTIVE

To evaluate the effect of autogenous periodontal ligament cell (PDL) transplantation in periodontal tissue regeneration.

METHODS

PDL cells derived from the same dog were cultured with alpha-MEM. 1 x 10(5) cells of first passage were allowed to attach to the collagen membrane for 24 hours. The membrane-cells were transplanted into periodontal defect in the same dog. Then the defects were covered with e-PTFE membranes. The defects covered only with e-PTFE were the controls. Eighteen teeth of 6 dogs for each group were included. The dogs were sacrificed after 6 weeks.

RESULTS

The results showed that new bone formation (4.00 +/- 0.13) mm in test group was significantly higher than that of in control group (3.09 +/- 0.28) mm, P < 0.05. The new cementum formation in test group was better than control group (P < 0.05).

CONCLUSION

The results suggested that PDL cell transplantation with guided tissue regeneration technique could enhance periodontal tissue regeneration in dogs.

Disturbance of electrolyte balance in vitreous of chicks with form-deprivation myopia

PURPOSE

To investigate the changes in the electrolyte and protein concentrations in the vitreous of 3-week-old chicks with form-deprivation myopia (FDM).

METHODS

FDM was induced in 2-day-old male white leghorn chicks by covering the left eye with a translucent plastic goggle and leaving the right eye uncovered to serve as control. After 19 days the animals were euthanized, and the axial dimensions of the eyes were measured with a caliper in an unfixed condition. The liquid vitreous and aqueous humor were removed by paracentesis, and blood was collected from the jugular vein. Sodium, potassium, and chloride concentrations were determined using ion-selective electrodes. Calcium and phosphate concentrations were determined by colorimetric assays using orthocresol phthalein complexone and bacterial xanthine oxidase, respectively.

RESULTS

The concentrations of potassium and phosphate were decreased, whereas chloride concentration was increased in the vitreous of the FDM eyes (P < .01). Sodium and calcium concentrations were similar to those in the control eyes. No significant changes in the concentration of electrolytes were observed in the aqueous humor. No significant differences were found in the protein concentrations in the liquid vitreous, gel vitreous, and aqueous humor.

CONCLUSIONS

Form-deprivation induced a significant increase of the volume of the liquid vitreous in the eye of the FDM chick. The increased liquid vitreous of the myopic eye was accompanied by an alteration of the electrolyte balance, by a mechanism that has not yet been clarified.

Impaired immunoproteasome assembly and immune responses in PA28-/- mice

In vitro PA28 binds and activates proteasomes. It is shown here that mice with a disrupted PA28b gene lack PA28a and PA28b polypeptides, demonstrating that PA28 functions as a hetero-oligomer in vivo. Processing of antigenic epitopes derived from exogenous or endogenous antigens is altered in PA28-/- mice. Cytotoxic T lymphocyte responses are impaired, and assembly of immunoproteasomes is greatly inhibited in mice lacking PA28. These results show that PA28 is necessary for immunoproteasome assembly and is required for efficient antigen processing, thus demonstrating the importance of PA28-mediated proteasome function in immune responses.

Induction of vascular endothelial growth factor after application of mechanical stress to retinal pigment epithelium of the rat in vitro

PURPOSE

To investigate the response to mechanical stress of vascular endothelial growth factor (VEGF) production by cultured retinal pigment epithelial (RPE) cells.

METHODS

A pulsatile stretch device was used in vitro. RPE cells of the second passage were seeded onto flexible-bottomed culture plates; then, at subconfluent culture, the plates were subjected to pulsatile stretch. Culture plates prepared in the same way but not subjected to stretch were used as controls. After stretching for 1 hour or 24 hours, conditioned medium for measurement of VEGF production by RPE cells was collected using a mouse VEGF immunoassay. To study the expression of VEGF in RPE cells, passaged-cultured RPE cells were exposed to pulsatile stretch for 0, 1, 3, or 14 hours. Total cytoplasmic RNA was then prepared from the RPE cells. Northern blot analysis was performed for VEGF, with G3PDH used as an internal control.

RESULTS

The expression and secretion of VEGF in RPE cells were increased by pulsatile stretching.

CONCLUSIONS

Results indicate that stretching of the RPE could result in increased production of VEGF, with associated risk for neovascularization and changes in the blood-retinal barrier.

A common disease haplotype segregating in spinocerebellar ataxia 2 (SCA2) pedigrees of diverse ethnic origin

The identification of a CAG trinucleotide repeat expansion, located within the coding sequence of the ataxin-2 gene, as the mutation underlying spinocerebellar ataxia 2 (SCA2) has facilitated direct investigation of pedigrees previously excluded from linkage analysis due to insufficient size or pedigree structure. We have previously described the identification of the ancestral disease haplotype segregating in the Cuban founder population used to assign the disease locus to chromosome 12q23-24.1. We now report evidence for the segregation of the identical core haplotype in pedigrees of diverse ethnic origin from India, Japan and England, established by the analysis of the loci D12S1672 and D12S1333 located 20kb proximal and 200 kb distal to the triplet repeat motif respectively. Interpretation of this data is suggestive that for these pedigrees at least, the mutation has arisen on a single ancestral or predisposing chromosome.

A parallel study on the effects in treatment of impotence by tonifying the kidney with and that without improving blood circulation

141 cases of functional impotence of the kidney-deficiency type were treated by tonifying the kidney. On them, 103 cases at the same time were treated by improving blood circulation and the other 38 cases by the former only. As a result the total effective rate and the markedly effective rate in the former were 84.46% and 46.60% respectively; but in the latter, 60.55% and 13.15%. A significant difference was found in Ridit analysis (P < 0.05), indicating that method of tonifying the kidney with improving blood circulation is much better than by simply tonifying the kidney alone.

Sterol synthesis. Preparation and characterization of fluorinated and deuterated analogs of oxygenated derivatives of cholesterol

Oxygenated sterols, including both autoxidation products and sterol metabolites, have many important biological activities. Identification and quantitation of oxysterols by chromatographic and spectroscopic methods is greatly facilitated by the availability of authentic standards, and deuterated and fluorinated analogs are valuable as internal standards for quantitation. We describe the preparation, purification and characterization of 43 oxygenated sterols, including the 4 beta-hydroxy, 7 alpha-hydroxy, 7 beta-hydroxy, 7-keto, and 19-hydroxy derivatives of cholesterol and their analogs with 25,26,26,26,27,27,27-heptafluoro (F7) and 26,26,26,27,27,27-hexadeuterio (d6) substitution. The 7 alpha-hydroxy, 7 beta-hydroxy, and 7-keto derivatives of (25R)-cholest-5-ene-3 beta, 26-diol (1d) and their 16,16-dideuterio analogs were also prepared. These d2-26-hydroxysterols and [16,16-2H2]-(25R)-cholest-5-ene-3 beta, 26-diol (1e) were synthesized from [16,16-2H2]-(25R)-cholest-5-ene-3 beta, 26-diol diacetate (2e), which can be prepared from diosgenin. The highly specific deuterium incorporation at C-16 in 1e and 2e should be useful in mass spectral analysis of 26-hydroxycholesterol samples by isotope dilution methods. The delta 5-3 beta, 7 alpha, 26- and delta 5-3 beta, 7 beta, 26-triols were regioselectively oxidized/isomerized to the corresponding delta 4-3-ketosteroids with cholesterol oxidase. Also described are 5,6 alpha-epoxy-5 alpha-cholestan-3 beta-ol, its 5 beta,6 beta-isomer, cholestane-3 beta, 5 alpha,6 beta-triol, their F7 and d6 derivatives, and d3-25-hydroxycholesterol, which was prepared from 3 beta-acetoxy-27-norcholest-5-en-25-one (30). The 43 oxysterols and most synthetic intermediates were isolated in high purity and characterized by chromatographic and spectroscopic methods, including mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. Detailed mass spectral assignments are presented, and 1H NMR stereochemical assignments are derived for the C-19 protons of 19-hydroxysterols and for the side-chain protons of 30.