Effect of otilonium bromide on contractile patterns in the human sigmoid colon

BACKGROUND

The mechanism of action of the spasmolytic compound otilonium bromide (OB) on human colonic motility is not understood. The aim of our study was to characterize the pharmacological effects of OB on contractile patterns in the human sigmoid colon.

METHODS

Circular sigmoid strips were studied in organ baths. Isolated smooth muscle cells from human sigmoid colon were examined using the calcium imaging technique.

KEY RESULTS

Otilonium bromide inhibited by 85% spontaneous non-neural rhythmic phasic contractions (RPCs), (IC(50) = 49.9 nmol L(-1)) and stretch-induced tone (IC(50) = 10.7 nmol L(-1)) with maximum effects at micromolar range. OB also inhibited by 50% both on- (IC(50) = 38.0 nmol L(-1)) and off-contractions induced by electrical stimulation of excitatory motor neurons. In contrast, the inhibitory latency period prior to off-contractions was unaffected by OB. OB inhibited acetylcholine-, substance P-, and neurokinin A-induced contractions. The L-type Ca(2+) channel agonist BayK8644 reversed the effects of OB on RPCs, on- and off-contractions. Hexamethonium, atropine, the NK(2) antagonist, or depletion of intracellular Ca(2+) stores by thapsigargin did not prevent the inhibitory effect of OB on RPCs and electrical contractions. KCl-induced calcium transients in isolated smooth muscle cells were also inhibited by OB (IC(50) = 0.2 micromol L(-1)).

CONCLUSIONS & INFERENCES

Otilonium bromide strongly inhibited the main patterns of human sigmoid motility in vitro by blocking calcium influx through L-type calcium channels on smooth muscle cells. This pharmacological profile may mediate the clinically observed effects of the drug in patients with irritable bowel syndrome.

The Caenorhabditis elegans genome: a multifractal analysis

The Caenorhabditis elegans genome has several regular and irregular characteristics in its nucleotide composition; these are observed within and between chromosomes. To study these particularities, we carried out a multifractal analysis, which requires a large number of exponents to characterize scaling properties. We looked for a relationship between the genetic information content of the chromosomes and multifractal parameters and found less multifractality compared to the human genome. Differences in multifractality among chromosomes and in regions of chromosomes, and two group averages of chromosome regions were observed. All these differences were mainly dependent on differences in the contents of repetitive DNA. Based on these properties, we propose a nonlinear model for the structure of the C. elegans genome, with some biological implications. These results suggest that examining differences in multifractality is a viable approach for measuring local variations of genomic information contents along chromosomes. This approach could be extended to other genomes in order to characterize structural and functional regions of chromosomes.

Quality of life two years after radical prostatectomy, prostate brachytherapy or external beam radiotherapy for clinically localised prostate cancer: the Catalan Institute of Oncology/Bellvitge Hospital experience

OBJECTIVE

The objective was to compare the short- and long-term impact of 3 different treatment modalities on health-related quality of life (HRQOL) in patients treated for localised prostate cancer at a single centre in Catalonia, Spain.

MATERIAL AND METHODS

This was a longitudinal, prospective study of 304 patients from a single centre in Catalonia, Spain. Patients underwent 1 of 3 treatment procedures: radical prostatectomy (114 patients), external beam radiation (134) or interstitial brachytherapy (56). HRQOL was assessed by both general and specific questionnaires, including the SF-36 health survey and the Expanded Prostate Cancer Index Composite (EPIC). Interviews were administered prior to treatment and at months 1, 3, 6, 12 and 24. One-way analysis of variance and generalised estimating equations models were constructed to assess between group differences in HRQOL.

RESULTS

After initial deterioration, HRQOL scores partially recovered, although significant differences between treatment groups persisted at two years. Worsening of urinary incontinence was especially marked for the radical prostatectomy group (11.45, p=0.005), while deterioration in the urinary irritative/obstructive domain was worse following brachytherapy treatment (4.76, p=0.025). Decline in sexual function was significantly greater for the radical prostatectomy group than for the brachytherapy group (18.74, p<0.001). No significant between-group differences were observed in bowel domain scores.

CONCLUSIONS

Quality of life 2 years after treatment for prostate cancer shows wide variability. Radical prostatectomy had the largest negative impact on the sexual and urinary incontinence domains. Differences between external radiation and brachytherapy were relatively small. Brachytherapy led to a moderate increase in urinary irritation compared to the other 2 groups.

Sperm concentration influences fertilization and male pronuclear formation in vitro in pigs

To study the effect of sperm concentration on the results of pig in vitro fertilization (IVF), 313 oocytes recovered from oviducts of prepubertal gilts after induction of ovulation were used. After capacitation, the number of live spermatozoa in the fertilization dishes was adjusted to 3 x 10(5), 6 x 10(5) and 12 x 10(5) cell/ml. After 4 hours of co-culture in TCM-199, the oocytes were pippeted to remove cumulus cells and the excess spermatozoa around the zona pellucida, and were transferred to fresh TCM-199 for another 12/14 hours. The results showed that 6 x 10(5) spermatozoa/ml is the optimum concentration for this system; the percentage of fertilized ova (71.6%) was not different from the best (76.8%), that was obtained with the highest concentration, and the percentage of monospermy (62.3%) was not different from the best (68.1%), that was obtained with the lowest concentration. The percentage of spermatozoa that reached the pronuclear stage increased while sperm concentration was decreased. The percentage of spermatozoa at the decondensed stage was decreased when the sperm concentration increased.

Selective stimulation of intrinsic excitatory and inhibitory motor pathways in porcine lower oesophageal sphincter

The mechanisms of stimulation of inhibitory and excitatory motor neurons (MNs) in the lower oesophageal sphincter (LOS) are not fully understood. The aim of this study was to assess the effect of selective stimulation of inhibitory and excitatory MNs in porcine LOS through nicotinic acetylcholine receptors (nAChRs), 5-HT(3) and P2X receptors. Circular LOS strips from adult pigs were studied in organ baths. We compared the effects of stimulation of MNs by electrical field stimulation (26 V, 0.3-20 Hz); nicotine (1-300 micromol L(-1)); 5-HT and 2-Me-5-HT (1 nmol(-1)-30 micromol L(-1)); and alpha,beta-methylene ATP (alpha,beta-meATP 1-100 micromol L(-1)); in standard Krebs solution; a non-adrenergic non-nitrergic non-purinergic (NANNNP) solution; and a non-adrenergic non-cholinergic (NANC) solution. Electrical stimulation of inhibitory MNs caused an intense LOS relaxation (-78.94 +/- 4.50% of LOS tone); and of excitatory MNs, a strong contraction (17.89 +/- 1.96 g). Nicotine 100 micromol L(-1) relaxed LOS (-84.67 +/- 3.98%) in standard Krebs solution, an effect reduced by Tetrodotoxin (TTX) 1 micromol L(-1). Nicotine induced a weak TTX-sensitive contraction (1.64 +/- 0.4 g) in NANNNP solution. 5-HT 10 micromol L(-1) and 2-Me-5-HT 30 micromol L(-1) contracted LOS in standard, NANC and NANNNP conditions, maximal responses (7.30 +/- 1.52 g, 3.50 +/- 0.18 g respectively) being reduced by TTX. alpha,beta-meATP 100 micromol L(-1) caused a LOS relaxation (-17.45 +/- 6.62%) unaffected by TTX in NANC solution, and a contraction (6.7 +/- 0.85 g) antagonized by TTX in NANNNP solution. Our results suggest selective mechanisms for stimulation of intrinsic excitatory and inhibitory motor pathways in porcine LOS. Inhibitory MNs are strongly stimulated by nAChRs and do not respond to stimulation of 5-HT(3) and P2X receptors. By contrast, excitatory MNs are stimulated through 5-HT(3) and P2X receptors, stimulation through nACRs being difficult and causing a weak response.

Deposition of Size-Selected Cu Nanoparticles by Inert Gas Condensation

Nanometer size-selected Cu clusters in the size range of 1-5 nm have been produced by a plasma-gas-condensation-type cluster deposition apparatus, which combines a grow-discharge sputtering with an inert gas condensation technique. With this method, by controlling the experimental conditions, it was possible to produce nanoparticles with a strict control in size. The structure and size of Cu nanoparticles were determined by mass spectroscopy and confirmed by atomic force microscopy (AFM) and scanning electron transmission microscopy (STEM) measurements. In order to preserve the structural and morphological properties, the energy of cluster impact was controlled; the energy of acceleration of the nanoparticles was in near values at 0.1 ev/atom for being in soft landing regime. From SEM measurements developed in STEM-HAADF mode, we found that nanoparticles are near sized to those values fixed experimentally also confirmed by AFM observations. The results are relevant, since it demonstrates that proper optimization of operation conditions can lead to desired cluster sizes as well as desired cluster size distributions. It was also demonstrated the efficiency of the method to obtain size-selected Cu clusters films, as a random stacking of nanometer-size crystallites assembly. The deposition of size-selected metal clusters represents a novel method of preparing Cu nanostructures, with high potential in optical and catalytic applications.

Hop Downy Mildew Caused by Pseudoperonospora humuli in Argentina

In Argentina, hop downy mildew disease caused by Pseudoperonospora humuli first appeared in Alto Valle of Rio Negro and Neuquen (1957), Mar del Plata (1962), and El Bolson (1963) (1). The disease occurred in the hop (Humulus lupulus L.) planting areas of El Bolson (Rio Negro) and Lago Pueblo (Chubut) in 2002 and 2003. Surveys were conducted in 30 commercial hop fields from December 2002 to March 2003 to estimate disease incidence and susceptibility of cultivars planted in these fields. Hop fields were divided into five sections and 100 plants were randomly selected and assessed for the presence of disease. Symptoms that were observed in early spring included dark brown rootstocks and primary basal spikes (stunted plants with pale and curled leaves), which are characteristic of systemic infection. Later in the season, secondary infections were characterized by dark purple-to-black lesions on leaves, flowers, cones, and lateral and terminal spikes. Plant symptoms and fungal morphological markers (dichotomously branched sporangiophores; ellipsoid and papillate sporangia) agreed with hop downy mildew disease and the fungus P. humuli. Yield loss was estimated as the reduction in yield compared with the 2001-2002 season observed from five hop growers. On December 10, 70% of the hop fields had greater than 50% disease incidence and seven fields reached 100% incidence. The reduction in cone yield varied between 20 and 34% in fields without a rootstock fungicide treatment. One field with a rootstock fungicide treatment (mefenoxam, copper oxiclorure, phosphorous acid, copper sulfate, and fosetyl-Al) and regular fungicide applications had a 30% increase in cone yield compared with 2001-2002. Systemically infected plants were recorded for hop cvs. Bullion, Cascade, CEZ, GS-19, Hallertauer Mfr., Nugget, Spalt, and Traful. Previously, Cascade was rated as a resistant cultivar to the root systemic infection (1). To our knowledge, this is the first record of a hop downy mildew outbreak in Argentina during the last 30 years. Reference: (1) L. Leskovar. El Lúpulo: Su Cultivo y Procesamiento. Hemisferio Sur. Buenos Aires, 1978.

Acalculous cholecystitis in a patient with Plasmodium falciparum infection after a trip to the Dominican Republic

Acalculous cholecystitis has been associated with several infectious agents, but its relation with Plasmodium falciparum infection has not been clearly defined. This is the first case of acalculous cholecystitis produced by Plasmodium falciparum infection that is directly documented and should be included among the differential diagnoses of acalculous cholecystitis.

The EORTC Quality of Life Questionnaire for patients with prostate cancer: EORTC QLQ-PR25. Validation study for Spanish patients

OBJECTIVES

The EORTC Quality of Life (QL) Group has developed a questionnaire, the EORTC QLQ-PR25, for evaluating QL in prostate cancer. The aim of this study is to assess the psychometric properties of the EORTC QLQPR25 when applied to a sample of Spanish patients.

MATERIALS AND METHODS

One hundred and thirty-seven prostate cancer patients with localised disease who started radiotherapy with radical intention combined with or without hormonotherapy prospectively completed the EORTC QLQ-C30 and EORTC QLQ-PR25 questionnaires three times: on the first and last day of radiotherapy and in the follow-up period. Psychometric evaluation of the questionnaires' structure, reliability and validity was conducted.

RESULTS

Multitrait scaling analysis showed that many of the item-scale correlation coefficients met the standards of convergent and discriminant validity. Exceptions appeared mainly in the scales for bowel symptoms and for hormonal- treatment-related symptoms. Cronbach's coefficients of the scales were good (0.72-0.86) for the urinary symptoms and sexual function scales but they were lower (<0.70) for the bowel and hormonal treatment scales. Most scales of the EORTC QLQ-PR25 had low to moderate intercorrelations. Correlations between the scales of the QLQ-C30 and the module were generally low. Group comparison analyses showed better QL in patients with higher Performance Status. Changes in QL appeared throughout the measurements. These were in line with the treatment process.

CONCLUSIONS

The EORTC QLQ-PR25 was a reliable and valid instrument when applied to a sample of Spanish prostate cancer patients. These results are in line with those of the EORTC validation study.

[Diffuse astrocytoma presenting as an optic-spinal syndrome]

INTRODUCTION

Spinal cord involvement is a rare presentation of grade II astrocytomas. Nevertheless, differentiation from inflammatory demyelinating diseases of the central nervous system can be challenging in some clinical situations. A patient with an optic-spinal syndrome due to a fibrillary astrocytoma is described.

CASE REPORT

A 32 years-old man was admitted to the hospital because of a subacute spinal cord syndrome. Brain MRI showed no abnormalities, and spinal MRI disclosed a cervical cord lesion suggestive of myelitis. Cerebrospinal fluid analysis revealed oligoclonal bands. Clinical improvement was observed after corticosteroid treatment. Three months later, the patient presented with binocular vision loss. A bilateral retrobulbar optic neuritis was suspected, and corticosteroid therapy was administered again. A new MRI with spectroscopy revealed an infiltrative lesion involving the right frontal lobe, optic chiasm, internal capsule, brainstem and cervical spinal cord, which was suggestive of low-grade astrocytoma. Brain biopsy confirmed the diagnosis of diffuse fibrillary astrocytoma.

CONCLUSION

Differential diagnosis between inflammatory and neoplastic lesions of the central nervous system requires close clinical-radiological follow-up. In this clinical situation, treatment response to corticosteroids and presence of oligoclonal bands in the cerebrospinal fluid may be not necessarily indicative of an inflammatory demyelinating process. Brain biopsy is often necessary for a definite diagnosis.

Stem cell differentiation by functionalized micro- and nanostructured surfaces

New fabrication technologies and, in particular, new nanotechnologies have provided biomaterial and biomedical scientists with enormous possibilities when designing customized supports and scaffolds with controlled nanoscale topography and chemistry. The main issue now is how to effectively design these components and choose the appropriate combination of structure and chemistry to tailor towards applications as challenging and complex as stem cell differentiation. Occasionally, an incomplete knowledge of the fundamentals of biological differentiation processes has hampered this issue. However, the recent technological advances in creating controlled cellular microenvironments can be seen as a powerful tool for furthering fundamental biology studies. This article reviews the main strategies followed to achieve solutions to this challenge, particularly emphasizing the working hypothesis followed by the authors to elucidate the mechanisms behind the observed effects of structured surfaces on cell behavior.

79 CHOLESTEROL QUANTIFICATION DURING CRYOPRESERVATION IN BOAR SPERM SAMPLES ENRICHED IN OR DEPRIVED OF CHOLESTEROL

Sperm membranes suffer significant lipid changes during cryopreservation similar to initial steps in capacitation, in which a reduction in plasma membrane cholesterol (pmCHO) is observed. Methyl-β-cyclodextrin (MBCD) or cyclodextrin pre-loaded with cholesterol (CLC; Purdy PH and Graham JK 2004 Cryobiology 48, 36–45) have been used to decrease or increase the pmCHO, respectively, in different mammalian spermatozoa. In this study, pmCHO levels were assessed during the cryopreservation process in boar sperm samples deprived of (D) or enriched in (E) CHO. Single sperm-rich fractions from 14 boars were divided in 4 aliquots and frozen in 0.5-mL straws after dilution in a lactose-egg yolk extender with a final concentration of 20% egg yolk and 3% glycerol (Control sample, C) and supplemented with MBCD (1 mg/120 × 106 cells; D sample) or CLC at 1 (E-1 sample) or 3 (E-3 sample) mg/120 × 106 cells. The pmCHO level was quantified at 17°C in pre-diluted sperm samples (basal pmCHO) and at 3 steps of the cryopreservation process: after cooling at 5°C (step 1), after the addition of 3% glycerol (step 2), and immediately after thawing (step 3). The pmCHO was quantified by an enzymatic colorimetric test (Spinreact®, Sant Esteve de Bas, Spain) at 520 nm, following the protocol described by Moore AI et al. (2005 Cryobiology 51, 241–249). Data (least squares means ± SEM) were expressed as micrograms of CHO/106 sperm and analyzed as a mixed-model ANOVA. Because there were significant differences (P ≤ 0.05) between ejaculates, this effect was included as random. The level of pmCHO in C, D, and E-1 samples followed the same trend without significant differences (P ≤ 0.05) among them. That level increased (P ≤ 0.05) at step 1 (0.55 ± 0.17; 0.52 ± 0.17; and 0.66 ± 0.17 for C, D, and E-1, respectively), compared with the basal level (0.24 ± 0.02), and decreased (P ≤ 0.05) to the basal level at steps 2 (0.23 ± 0.07; 0.23 ± 0.07; and 0.30 ± 0.07 for C, D, and E-1, respectively), and 3 (0.07 ± 0.02; 0.08 ± 0.02; and 0.13 ± 0.02 for C, D, and E-1, respectively). Although the pattern in E-3 was similar to other treatments, the level of pmCHO was greater (P ≤ 0.05) than those at step 1 (0.75 ± 0.17), 2 (0.51 ± 0.07), and 3 (0.16 ± 0.02). In conclusion, the pre-freezing treatment of sperm samples with methyl-β-cyclodextrin, to reduce the CHO, did not modify the CHO level of plasma membrane of boar spermatozoa. However, treatment with cyclodextrin pre-loaded with CHO at 3 mg/120 × 106 cells increased significantly the CHO level of plasma membrane, which was evident throughout the cryopreservation process. Supported by AGL2006-07769/GAN, AGL2005-00760/CICYT, Madrid, and GERM (04543/07), Murcia, Spain.

[Use of a blood recuperating device. Total knee arthroplasty]

The authors evaluate the adoption of a protocol to recuperate blood from drainage during surgery for knee prosthesis. They carried out a prospective study on 19 patients diagnosed with knee arthrosis and who underwent surgery for Total Knee Arthroplasty from September 2006 through June 2007. The medical instrument used was Bellovac, produced by Astral Tech. In the Post anesthesia Reanimation Unit, four patients received a homologous transfusion (27.50%). Prior to the adoption of this protocol, the rate of transfusion was 37%. Hemoglobin during preoperative procedures was not a risk factor for a homologous transfusion. This is associated with the volume drained and reinserted. Patients who received a transfusion had drained 450 cc or more. The study did not record any complication due to the use of the recuperating device. The use of this device made it possible to decrease homologous blood transfusions.