In irritable bowel syndrome, postprandial abdominal distention is associated with a reduction of intestinal tone.

BACKGROUND: The pathophysiology of abdominal distention in irritable bowel syndrome (IBS) is still a matter of debate, but the relationship between modifications of intestinal tone and abdominal volume has never been analyzed. METHODS: Eighty-four patients affected by IBS and reporting moderate to severe abdominal distention were enrolled. Thirty-nine presented abdominal distention immediately after and forty-five presented abdominal distention independently of meal intake. Twenty healthy volunteers (HV), comparable for gender and age, were also enrolled. All the subjects underwent fasting and postprandial recto-sigmoid volume monitoring with barostat and abdominal girth measurement to evaluate abdominal distention. KEY RESULTS: In comparison with HV (75±13 mL) and with patients with meal-unrelated abdominal distention (135±56 mL), in the subgroup of patients with severe meal-related abdominal distention recto-sigmoid tone response to the meal was significantly reduced (mean increase of balloon volume 184±89 mL; P<.001), paralleling abdominal girth increase and occurring immediately after test meal intake. Meal-induced abdominal girth modification was significantly correlated with meal-related modification of recto-sigmoid tone (r=.71) and abdominal symptoms. CONCLUSIONS: In patients with IBS suffering from severe postprandial abdominal distention, a postprandial reduction of intestinal tone is associated with this bothersome symptom. Further studies are needed to evaluate whether drugs acting on the modification of intestinal tone could be useful in the treatment of these patients.

Hydrogen breath test in patients with severe constipation: the interference of the mixing of intestinal content.

BACKGROUND: The diagnostic accuracy of the hydrogen (H2 ) breath test might be reduced by the release of preformed H2 , trapped in hard stools. Test solution ingestion might induce the mixing of colonic content and a false positive result. We studied severely constipated patients, at diagnosis and after the normalization of bowel function, to clarify whether this mechanism affects test results. METHODS: Twenty functional constipated patients, 10 consecutive patients with functional diarrhea and 10 healthy volunteers underwent (i) a H2 breath test after lactulose, to exclude differences among the groups in fermenting capacity; (ii) breath H2 excretion monitoring after non-absorbable, non-fermentable PEG-electrolyte solution, to exclude the role of the delivery to the colon of preexisting fermentable substrates or of the release of preformed H2 entrapped in the feces; (iii) H2 measurement during a 7-h fasting period, to exclude the role of spontaneous variations of breath gas excretion; and (iv) breath H2 excretion monitoring after PEG, after normalization of bowel function. KEY RESULTS: All the subjects excreted similar amounts of H2 after lactulose. After PEG, only severely constipated patients showed significant breath H2 excretion, theoretically able to induce a false positivity of the lactose breath test in 70% of patients and a false positivity of glucose breath tests in 50% of patients. Breath H2 excretion after PEG disappeared if fecal consistency improved after therapy. CONCLUSIONS & INFERENCES: Severely constipated patients may harbor preformed gas in hard stools which can be released when mixing of the intestinal content is induced. This mechanism may interfere with breath test results.

Hydrogen breath test and intestinal gas production.

Despite extensive use in clinical practice, difficulties regarding interpretation of hydrogen breath test are still very frequent, even on research grounds. After the administration of a non-absorbable sugar, such as lactulose, an increase of breath hydrogen and methane is evident; this phenomenon is considered an index of colonic fermentation. It is not clear, however, if the levels of these compounds correlate with the presence and severity of functional symptoms, nor if they accurately reflect gas production at colonic level. So far, apart from flatulence, we have no indications regarding the ability of hydrogen or methane to act as biomarkers of intraluminal events. On the other hand, it has been shown that in functional bowel disease a colonic dysbiosis exists, and that the modification of bacterial flora might result in a reduction of symptom severity. Consequently, it is not clear if hydrogen and methane colonic production could have a role in the pathophysiology of functional complaints, but it is possible that other fermentation products should be taken into consideration, such as acetate, propionate, and alcohol.

Identification and quantification of constituents of Gardenia jasminoides Ellis (Zhizi) by HPLC-DAD-ESI-MS.

A simple, rapid and specific HPLC method was carried out for the analysis of characteristic constituents in Gardenia jasminoides Ellis (Zhizi), namely iridoids, caffeoyl quinic acid derivatives and crocins. The separation was successfully obtained using a C(18) column by gradient elution with mixtures of methanol and water as mobile phases; detection wavelength was set at 240 nm for iridoid glycosides, 315 nm for quinic acid derivatives and 438 nm for crocins. The analytical method was validated and the quantification of active compounds, namely iridoids, was performed. Linearity, precision, repeatability, stability, accuracy, limit of detection (LOD) and limit of quantification (LOQ) were also reported. This assay was successfully applied for qualitative and quantitative analysis of five commercial samples of G. jasminoides Ellis.

Cyclodextrins as carriers for kavalactones in aqueous media: spectroscopic characterization of (S)-7,8-dihydrokavain and beta-cyclodextrin inclusion complex.

Kavalactones represent the active constituents of kava-kava (Piper methysticum G. Forster), endowed with sedative and anaesthetic properties. Kavalactones are polar constituents, but poorly soluble in water with a low bioavailability. In this study, the formation of inclusion complexes of one of the most representative kavalactone isolated from kava-kava extract, (S)-7,8-dihydrokavain (DHK), with beta-cyclodextrin (beta-CyD) was investigated mainly by spectroscopic methods. NMR experiments were extensively used for the complete characterization of the complex and included (1)H NMR complexation shifts analysis, (1)H NMR diffusion measurements (DOSY), and ROESY experiments. In particular DOSY experiments demonstrated that in the presence of beta-CyD the translational diffusion of kavalactone is sizably slowed down (2.5x10(-10)m(2)/s) with respect to the free drug (4.4x10(-10)m(2)/s) according to the inclusion of DHK in the cavity of (beta-CyD). ROESY experiments confirmed the inclusion of DHK in the hydrophobic pocket of beta-CyD through the primary hydroxyl rim, being the most relevant interactions between the H3' of beta-CyD and the ortho protons on the phenyl ring of the DHK, and between H5' of beta-CyD and the meta/para protons of DHK phenyl ring. The inclusion of the phenyl ring of DHK, leaving the lactone moiety outside of CyD was also confirmed by the induced CD effects. The binary solution DHK/beta-CyD shows a 50% intensity increase of the negative band of the pi-pi* transitions of the phenyl ring with respect to the absorption observed with DHK alone. Molecular dynamics simulations results corroborated and further clarify observed spectroscopic data. It was found that the phenylethyl substituent at C6 has a preferential equatorial position in the free state, and an axial one in the complex, justifying the large downfield shift experienced by H6 of DHK upon binding. Finally the influence of beta-CyD on water solubility of DHK was investigated by phase-solubility studies. In the range 2-4mM of host, solubility of DHK was increased only two-fold, but being beta-CyD also a penetration enhancer, in vivo studies will be performed to clarify a possible role of the complex on the bioavailability of DHK.

Pharmacological in vivo test to evaluate the bioavailability of some St John's Wort innovative oral preparations.

In this study, the optimisation of biopharmaceutical properties of a dried commercial extract of St John's Wort were evaluated employing the in vivo forced swimming test (FST). Three new dosage forms containing beta-cyclodextrin and surfactants (SDS, ASC8) were compared in the FST with the commercial extract. The commercial extract showed antidepressant activity in mice after 60 min at a dosage of 100 mg/kg. The same antidepressant activity appeared in 30 min with a micellar solution of SDS containing the same quantity of extract (100 mg/kg), while with micelles of ASC8 the effect appeared at 15 min and with a dosage of 30 mg/kg. In the case of beta-cyclodextrin the best results were obtained at 30 min, administering 60 mg/kg of the extract. Finally, the influence of the formulations on the water solubility of the constituents of the extract is reported. The tensides dramatically enhanced solubility, in particular that of the more lipophilic compounds, in the case of beta-cyclodextrin this effect was very pronounced for flavonoids and biapigenin, lower for hypericins and practically insignificant for hyperforins.

Complete long-term response to radiotherapy of gastric early-stage marginal zone lymphoma resistant to both anti-Helicobacter pylori antibiotics and chemotherapy.

BACKGROUND: The optimal approach to patients with gastric lymphoma of extranodal mucosa-associated lymphoid tissue (MALT) that resist to anti-Helicobacter pylori (HP) eradication therapy is still to be defined. PATIENTS AND METHODS: From January 1997 to December 2004, we observed 24 patients affected with newly diagnosed early-stage and HP-positive gastric lymphoma of the MALT type. Five of them resisted to oral anti-HP antibiotic regimens and to subsequent one (two patients) or two (three patients) chemotherapy regimens. Age ranged between 51 and 77 years (median 70); three were females. Translocation (11;18) was ascertained in one subject. They were admitted to local radiation therapy with a total dose of 30 Gy. RESULTS: All such resistant patients achieved complete remission after radiotherapy. No relapses were observed after 21, 45, 48, 52, and 67 months of uninterrupted follow-up. Early toxicity was very low and consisted of mild nausea. Late toxicity or secondary malignancy was not recorded so far. CONCLUSIONS: Radiotherapy proved to be effective and safe for early-stage HP-positive gastric extranodal lymphoma of MALT type that is resistant to anti-HP eradication antibiotics and to following chemotherapy. Radiotherapy might be suggested as principal salvage therapy after resistance to HP eradication, instead of chemotherapy.

Analysis and stability of the constituents of St. John's wort oils prepared with different methods.

St. John's wort is a medicinal plant with a long history of use in traditional medicine all over Europe. Traditional preparations and in particular the infused oil from SJW flowers remains one of the most popular and curative topical remedy against ulcerations and burns. The presence of the characteristic polyprenylated acylphloroglucinol derivatives, namely hyperforin and analogs are instead related to the oil's therapeutic activity. Indeed, it is well known that hyperforin has a potent antibacterial activity. In this study we tried to rationalize the production system of the oily preparation in order to obtain the highest concentration and stability of phloroglucinols. Five different samples of SJW oils were evaluated by HPLC-DAD-MS analysis to verify the variability and stability of the constituents according to the following factors: different harvesting time, fresh or dried plant material, use of sunlight or heating systems during extraction. The stability of these oils during 1 year was also tested.

Simultaneous analysis of artemisinin and flavonoids of several extracts of Artemisia annua L. obtained from a commercial sample and a selected cultivar.

Artemisia annua L. (Qinghao) is a promising and potent antimalarial herbal drug. This activity has been ascribed to its component artemisinin, a sesquiterpene lactone that is very effective against drug-resistant Plasmodium species with a low toxicity. Our studies indicate that several flavonoids of A. annua can promote and enhance the reaction of artemisinin with hemin. These data are in good agreement with previous investigations on the in vitro potentiation of antimalarial activity of artemisinin by such flavonoids. As a consequence, in view of a possible use of the phytocomplex rather than pure artemisinin, an HPLC/DAD/MS method is proposed for the simultaneous detection and quantification of both flavonoids and artemisinin. Different extracts, obtained from two different herbal drugs, a commercial sample and a selected cultivar, were analyzed in order to determine which solvents provide the best yields of both artemisinin and flavonoids. Qualitative and quantitative results obtained using an HPLC method are described, which will be useful for developing highly effective herbal drug preparations.

Evaluation of skin permeability of sesquiterpenes of an innovative supercritical carbon dioxide Arnica extract by HPLC/DAD/MS.

Recently, a supercritical carbon dioxide dried extract of Amica flower, with a very high sesquiterpene content was developed. In view of using this extract in formulations for cutaneous application, the ability of sesquiterpenes to permeate the skin was evaluated by HPLC/DAD/MS using the following permeation enhancers: oleic acid (OA), dimethylsulfoxide (DMSO), lauroglycol, isopropyl myristate and Tween 80. A skin permeation study was performed using a modified Franz diffusion cell and the human stratum corneum and epidermis as membrane. Solutions of the enhancers were directly analysed after dilution with methanol or DMSO. A simple RP-HPLC-DAD-MS method for the quantification of the sesquiterpenes was developed and the method showed no interference with the other substances extracted from the skin and the permeation enhancers. The study evidenced that among the selected skin permeation enhancers, DMSO and OA canbe considered as good candidates to be used in preparations for cutaneous application.

An optical DNA-based biosensor for the analysis of bioactive constituents with application in drug and herbal drug screening.

The efficient and rapid detection of bioactive compounds in complex matrices of different origins (natural or synthetic) is a key step in the discovery of molecules with potential application in therapy. Among them, molecules able to interact with nucleic acids can represent important targets. In this study, an optical DNA biosensor, based on surface plasmon resonance (SPR) transduction, has been studied in its potential application as new analytical device for drug screening. This device was applied to the analysis of pure synthetic or natural molecules and also to some fractions obtained by chromatographic separation of an extract of Chelidonium majus L. (great celandine), a plant containing benzo[c]phenanthridinium alkaloids having intercalating properties. The ability of these molecules to interact with the double stranded nucleic acid (dsDNA) immobilised on the sensor surface has been investigated. The optical sensing relies on the SPR-based bench instrument Biacore Xtrade mark and represents an example of multiuse sensor. The results obtained demonstrate the potential application of this device for the rapid screening of bioeffective compounds. The characteristics of the biosensor offer the possibility to be coupled to chemical analysis as in hyphenated technologies.

[Ventricular tachycardia "in salvoes"]. / Les tachycardies ventriculaires en salves.

The term of ventricular tachycardia "in salvoes" describes electrophysiographic appearances of several consecutive ectopic ventricular beats without interposition of sinus rhythm. This is an intermediate arrhythmic state between isolated ventricular extrasystoles and sustained ventricular tachycardia. The generally accepted definition of the term "sustained" implies a duration of over 30 seconds or poor haemodynamic tolerance. Strictly speaking, the term "salvoe" has no precise definition in cardiology. In the 1996 edition of the Petit Robert French dictionary, the term is defined as the simultaneous discharge of guns or successive blasts of canons. The Delaware medical dictionary does not provide a French definition of the term "salvoe". In practice, we use the term tachycardia in salvoes in the same meaning as ventricular tachycardia. Schematically, in clinical practice, two situations may be encountered. In the first case, salvoes of VT are recorded in apparently normal hearts; they are not life-threatening and, though often nearly asymptomatic, they may pose therapeutic problems. In the second case, the arrhythmia occurs in a diseased heart, with a low ejection fraction, in which the essential problem is the vital prognosis.

A diffusion-ordered NMR spectroscopy study of the solubilization of artemisinin by octanoyl-6-O-ascorbic acid micelles.

Artemisinin (QHS) is a natural drug with a very low solubility in water. To improve its availability in hydrophilic media, it was solubilized in micellar dispersions of octanoyl-6-O-ascorbic acid (ASC8), a relatively novel surfactant that combines surface activity with powerful performance as radical scavenger. In this article we report a study based on diffusion-ordered NMR spectroscopy (DOSY) measurements carried out on QHS/ASC8 micellar dispersions. QHS is efficiently solubilized by ASC8 micelles, with no significant perturbation of the micellisation.

Atypical atrial flutters.

Typical atrial flutter is due to a counterclockwise macro-re-entry circuit localized in the right atrium with a surface ECG pattern showing predominantly negative F waves in the inferior leads and positive F waves in V1. Recently it has been proposed to classify atrial flutter on the basis of its cavo-tricuspid isthmus dependence rather than on the ECG pattern. Therefore some atrial flutters are considered typical even if the ECG does not exhibit a typical pattern. This is the case for reverse typical atrial flutter, lower loop re-entry and partial-isthmus-dependent short circuit flutter. The term atypical flutter refers to a non-isthmus dependent flutter. Usually these patients have had previous cardiac surgery with a right or left atriotomy. Flutter involving a spontaneous right atrial scar is not uncommon.

Analysis and stability of the constituents of artichoke and St. John's wort tinctures by HPLC-DAD and HPLC-MS.

In continuing our investigations on tinctures, which represent both herbal drug preparations and herbal medicinal products, 40% and 60% v/v tinctures of artichoke and St. John's wort were investigated. Artichoke is largely used in hepatic disorders, while St. John's wort is an anti-inflammatory, antidepressant, and healing agent. Both herbal drugs contain various constituents, although the compounds responsible for the main effects have not yet been completely identified. However, caffeoylquinic acids and flavones seem to be of crucial importance for the activity of artichoke, as well as flavonoids, naphthodianthrones, and phloroglucinol derivatives for St. John's wort, and they are used as marker constituents. Thus, quantification of all these constituents was performed using high-performance liquid chromatography-diode array detection (HPLC-DAD) and HPLC--mass spectrometry (MS) analyses with rutin as external standard. In addition the stability of the constituents of these tinctures from accelerated and long-term testing was also evaluated. From the results it was evidenced that constituent content depends on the solvent used for the extraction. The stability was also shown to be very different and seems to be related to the water content of the tinctures.

[Nodal conduction]. / La conduction nodale.

The existence of a single atrio-ventricular fascicle had been suggested in the 19th century by Wilhelm His junior. In 1906, Sunao Tawara described in details the existence of a specific muscular fascicle in charge of the atrio-ventricular conduction. Since, it has remained famous under the name of atrio-ventricular node. It is located in the apical part of the Koch triangle. It is 5 to 7 mm long and 2 to 5 mm wide and includes often an enlargement of its compact portion along the fibrous annulus to the coronary sinus ostium which seems to be associated with the development of a intra- or atrio-nodal re-entry circuit. Its action potentials are qualified as "slow response" and propagate with a speed of 0.02 to 0.05 m/sec (which is comparable to that present in the sinus node). This propagation slowness explains the PR interval on surface EKG tracings and the AH interval in intra-cardiac electrogram. When AV node cells are requested by a rapid atrial rhythm, their physiological response is made under the mode of beatings group described by Luigi Luciani and Karel Wenckebach, prior to the EKG's invention. The atrio-ventricular physiological relationship during the atrial acceleration is made according to the Luciani-Wenckebach mode and then 2/1 mode as described in the non-linear dynamics theory. The most frequent pathological of the nodal conduction are the atrio-ventricular blocks and nodal duality. They are described and commented in this article. The nodal conduction disturbances are currently accessible to different therapeutic patterns such as cardiac pacing or ablative techniques. Nonetheless the innermost mechanism are still incompletely identified and will for sure be a matter of numerous studies in the future.

Variability in the content of the constituents of Hypericum perforatum L. and some commercial extracts.

Seven samples of Hypericum perforatum L. (St. John's wort) were collected throughout Tuscany; the dried extracts were assayed to determine the concentration of the constituents. Total flavonol content ranged from 4.58% to 15.90%; hypericins ranged from 0.05% to 0.11%; and hyperforins ranged from 1.37% to 20.80%. In addition, four commercially dried extracts were analyzed using the same high-performance liquid chromatographic (HPLC) method; their flavonol contents varied from 10.64% to 15.01%, hypericins varied from 0.03% to 0.20%, and hyperforins varied from 1.18% to 6.54%. The aim of this investigation was to evaluate the contents of the different constituents depending on environmental factors and drying and storage conditions of the wild samples. In addition, the contents of the constituents of the products available to the consumer that were related to quality and the relation of this to safety and efficacy were also evaluated.

Analysis of plant complex matrices by use of nuclear magnetic resonance spectroscopy: St. John's wort extract.

The efficiency of two-dimensional homonuclear (1)H--(1)H correlated spectroscopy and two-dimensional reverse heteronuclear shift correlation spectroscopy (i.e., heteronuclear multiple quantum correlation) in characterizing and evaluating the relative content of herbal extract constituents is demonstrated. These experiments are able to fully assign the proton and carbon resonances of all three classes of constituents present in dried commercial extract of St. John's wort, that is, flavonols, phloroglucinols, and naphthodianthrones, with particular regard to the very unstable phloroglucinols. In addition, shikimic and chlorogenic acids, sucrose, lipids, polyphenols, and traces of solvents of the extractive process (methanol) were also identified. These experiments can be considered to be a very simple and fast analytical method for determining the quality and stability of the titled commercial extract. They represent a generally applicable technique for a rapid screening and a specific measurement of other commercial phytochemicals or, in selected cases, an alternative to the classical analytical techniques such as high-performance thin-layer chromatography, high-performance liquid chromatography, capillary gas chromatography, and electrophoresis.

Evaluation of chemical stability of St. John's wort commercial extract and some preparations.

Thermal and photostability of a commercial dried extract and capsules of St. John's wort (Hypericum perforatum L.) were evaluated under the ICH test conditions. The extract was considered as drug substance and its preparations as drug products. In addition, capsules of different colours corresponding to different opaficient and pigment contents were also evaluated as primary package of drug product and the tests in the secondary pack were performed with amber containers, as well. A selective high-performance liquid chromatography (HPLC) for determination of stability of all the characteristic constituents, namely flavonols, hyperforins and hypericins, was carried out. Photostability testing showed all the constituents to be photosensitive in the tested conditions. However, different opaficients and pigments present in the capsules influenced the stability of the different classes of constituents. Amber containers suggested as secondary packages influenced only in part the photostability of the investigated constituents. Long-term thermal stability testing showed a very low (less than 4 months) hyperforins and hypericins t(90), even if ascorbic and citric acids were added to the formulation. From the results we have obtained it is clear that for St. John's wort preparations, a mere translation of the ICH guidelines to the field of herbal products, as suggested by the WPHMP of the EMEA, cannot be accepted. A revision and adaptation of the storage conditions should be elaborated.