Chemical imaging of single catalyst particles with scanning µ-XANES-CT and µ-XRF-CT.

The physicochemical state of a catalyst is a key factor in determining both activity and selectivity; however these materials are often not structurally or compositionally homogeneous. Here we report on the 3-dimensional imaging of an industrial catalyst, Mo-promoted colloidal Pt supported on carbon. The distribution of both the active Pt species and Mo promoter have been mapped over a single particle of catalyst using microfocus X-ray fluorescence computed tomography. X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure revealed a mixed local coordination environment, including the presence of both metallic Pt clusters and Pt chloride species, but also no direct interaction between the catalyst and Mo promoter. We also report on the benefits of scanning µ-XANES computed tomography for chemical imaging, allowing for 2- and 3-dimensional mapping of the local electronic and geometric environment, in this instance for both the Pt catalyst and Mo promoter throughout the catalyst particle.

Critical appraisal of the revised Ghent criteria for diagnosis of Marfan syndrome.

Marfan syndrome (MFS) is a connective tissue disorder with major features in cardiovascular, ocular and skeletal systems. Recently, diagnostic criteria were revised where more weight was given to the aortic root dilatation. We applied the revised Marfan nosology in an established adult Marfan population to define practical repercussions of novel criteria for clinical practice and individual patients. Out of 180 MFS patients, in 91% (n = 164) the diagnosis of MFS remained. Out of 16 patients with rejected diagnosis, four patients were diagnosed as MASS (myopia, mitral valve prolapse, borderline non-progressive aortic root dilatation, skeletal findings and striae) phenotype, three as ectopia lentis syndrome and in nine patients no alternative diagnosis was established. In 13 patients, the diagnosis was rejected because the Z-score of the aortic root was <2, although the aortic diameter was larger than 40 mm in six of them. In three other patients, the diagnosis of MFS was rejected because dural ectasia was given less weight in the revised nosology. Following the revised Marfan nosology, the diagnosis of MFS was rejected in 9% of patients, mostly because of the absence of aortic root dilatation defined as Z-score ≥2. Currently used Z-scores seem to underestimate aortic root dilatation, especially in patients with large body surface area (BSA). We recommend re-evaluation of criteria for aortic root involvement in adult patients with a suspected diagnosis of MFS.

In vitro and in vivo multidrug resistance reversal activity by a Betti-base derivative of tylosin.

BACKGROUND: The multidrug resistance (MDR) proteins are present in a majority of human tumours. Their activity is important to understand the chemotherapeutic failure. A search for MDR-reversing compounds was conducted among various Betti-base derivatives of tylosin. METHODS: Here, we evaluate the in vitro and in vivo P-glycoprotein (P-gp)-modulating activity of the most promising compound N-tylosil-1-alpha-amino-(3-bromophenyl)-methyl-2-naphthol (TBN) using human MDR1 gene-transfected and parental L5178 mouse lymphoma cell lines. RESULTS: In vitro experiments showed that TBN dramatically increased the P-gp-mediated cellular uptake of the fluorescent substrate rhodamine 123. Similarly, TBN was found to act as a very potent enhancer of the cytotoxicity of doxorubicin on the resistant cell line. We also provide in vivo evidence using DBA/2 mice in support for an increased tumoural accumulation of doxorubicin, without affecting its tissue distribution, resulting in an enhanced antitumoural effect. CONCLUSION: Our results suggest that TBN is a potent modulator of the P-gp membrane pump and that the compound could be of clinical relevance to improve the efficacy of chemotherapy in MDR cancers.

Delayed spinal cord injury following microchip placement in a dog.

A three-year-old female, entire Yorkshire Terrier dog was examined because it had progressive non-weight-bearing left forelimb lameness and tetraparesis of two weeks duration. Clinical signs were first observed following mating. Examination confirmed non-weight-bearing left forelimb lameness and tetraparesis. Left forelimb muscle atrophy was also noticed. Survey radiography revealed a metallic foreign body consistent with a microchip in close proximity to the left articular facets between the fifth and sixth cervical vertebrae. Computed tomography identified the exact location of the foreign body encroaching on the left dorsolateral vertebral canal, and osteolysis of the lamina of the sixth cervical vertebra. Surgical removal of the foreign body was performed via a dorsal approach to the caudal cervical vertebral column. Two weeks following surgery the dog showed return of left forelimb function and resolving tetraparesis. Microchip implantation had been performed three years previously.

A class III transcription factor composed of RNA.

It is generally assumed that the machinery that transcribes genes is composed entirely of polypeptides. However, in vitro transcription by silkworm RNA polymerase III requires a transcription factor that is not a polypeptide. This component, TFIIIR, is distinct from the previously identified transcription components: RNA polymerase III, and the accessory factors TFIIIA, TFIIIB, TFIIIC, and TFIIID. The newly discovered TFIIIR is a macromolecule that appears to be composed of RNA. It is resistant to heat, detergent, phenol, protease, and deoxyribonuclease, but it is sensitive to alkali and ribonuclease.

Ethanol and amino acids in the central nervous system: assessment of the pharmacological actions of acamprosate.

Ethanol induces alterations in the central nervous system by differentially interfering with a number of neurotransmitter systems, although the mechanisms by which such effects are executed are not well understood. The present review therefore, is designed to ascertain the effect of ethanol on both excitatory and inhibitory amino acid neurotransmitters, as well as the sulphonated amino acid taurine, assayed by the microdialysis technique within specific brain regions of rat during different types of alcohol intoxication, acute and chronic, as well as during the withdrawal period. Such an understanding of these pharmacological actions of ethanol on neurotransmitters is essential in order to provide the impetus for the development of appropriate therapeutic intervention to ameliorate the multitude of neurochemical disorders induced by ethanol. In addition the possible mode of action of a new therapeutic drug for the treatment of alcoholism, acamprosate will be discussed. The first part of this review will be limited to studies of the effect of ethanol on both amino acid neurotransmitters and the sulphonated amino acid taurine, a possible neuromodulator. While, the second part will seek to establish the possible mechanism of action of a new therapeutic drug, acamprosate, which is used to combat the effects of ethanol, particularly during the craving period, as well as maintaining abstinence in weaned alcoholics.

Improved efficiency of hybridoma ascites production by intrasplenic inoculation in mice.

Intrasplenic inoculation of small numbers (10(4)) of antibody-producing hybridoma cells into unprimed BALB/c mice resulted in high-titered ascites. By intrasplenic injection, the low number of cells needed to produce ascites was 2-3 logs fewer than that required by ip inoculation. Hybridoma cells suspended in the ascitic fluid could be reestablished in vitro. Furthermore, cells obtained directly from individual, cloned colonies or from previously frozen samples also resulted in high-titered ascites, if the cells were inoculated intrasplenically. This method reduces time and expense required to grow large numbers of hybridoma cells for ip-derived ascites production and allows ready recovery of frequently unstable frozen-thawed cells.

Epidermal growth factor-mediated targeting of chlorin e6 selectively potentiates its photodynamic activity.

Certain tumor cells, such as squamous carcinoma cells, express an increased number of epidermal growth factor (EGF) receptors. Therefore, we studied the targeted delivery of the photocytotoxic compound Sn-(IV)chlorin e6 monoethylenediamine [SnCe6(ED)] to tumors that overexpress the EGF receptor. EGF was conjugated to SnCe6(ED) through a carrier, such as dextran (Dex) and human serum albumin (HSA), and the photocytotoxicity on the EGF receptor-overexpressing MDA-MB-468 breast adenocarcinoma cell line was evaluated. The photobiological activities of these EGF conjugates, of the conjugates of the photosensitizer to HSA or Dex, or of the photosensitizer alone were compared. The affinity of EGF for its receptor was substantially impaired when conjugated in EGF-Dex-SnCe6(ED), in contrast to EGF-HSA-SnCe6(ED). In corresponding results, EGF-HSA-SnCe6(ED) displayed a high photocytotoxicity (IC50, 63 nM) on MDA-MB-468 cells at a light dose of 27 kJ/m2, whereas EGF-Dex-SnCe6(ED) showed very limited photocytotoxicity. EGF-HSA-SnCe6(ED) was no longer photocytotoxic in the presence of a competing EGF concentration. The high photocytotoxicity of EGF-HSA-SnCe6(ED) was shown to be the result of a high intracellular concentration in MDA-MB-468 cells, which could be lowered dramatically by incubating the conjugate with a competing EGF concentration. In contrast, EGF-Dex-SnCe6(ED) accumulated poorly in MDA-MB-468 cells, in agreement with its low EGF receptor affinity and photocytotoxicity. EGF-HSA-SnCe6(ED) produced much more intracellular reactive oxygen species on light irradiation than EGF-Dex-SnCe6(ED). It is concluded that the photodynamic activity of the EGF-HSA conjugate of SnCe6(ED) on MDA-MB-468 breast adenocarcinoma cells is EGF specific and is much more potent than EGF-Dex-SnCe6(ED) or free SnCe6.

[Persistent shoulder symptoms in calcific tendinitis: clinical and radiological predictors]. / Aanhoudende schouderklachten bij tendinitis calcarea.

OBJECTIVE: We assessed the most important demographics and radiological characteristics at the time of diagnosis of rotator cuff calcific tendinitis (RCCT), and their associations with long-term clinical outcome. DESIGN: Observational study. METHOD: Baseline characteristics and treatment were evaluated in 342 patients in whom RCCT had been diagnosed. Interobserver agreement of the radiological investigations was analysed. Patients were sent a general questionnaire and 2 shoulder questionnaires, the "Western Ontario rotator cuff" (WORC) and the "Disabilities of the arm, shoulder and hand" (DASH) for evaluation of long-term clinical outcome. Associations between baseline characteristics and long-term outcomes were analysed using logistic regression. RESULTS: Mean age at diagnosis was 49.0 years (SD = 10.0), and 60% were female. The dominant arm was affected in 66%, and 21% had bilateral RCCT. Calcifications were on average 18.7 mm in size (SD = 10.1, ICC = 0.84 (p < 0.001)) and located 10.1 mm (SD = 11.8) medially to the acromion (ICC = 0.77 (p < 0.001)). 32% of the calcifications had a Gärtner type I classification (κ: 0.47 (p<0.001)). After a mean follow-up of 14 years (SD =7.1), median WORC score was 72.5 (range: 3.0-100.0) and median DASH score 17.0 (range: 0.0-82.0). Female gender, dominant arm involvement, bilateral disease, longer duration of symptoms at presentation, and presence of multiple calcifications were associated with inferior long-term outcomes. CONCLUSION: RCCT is not self-limiting. Radiological variations have no significant predictive value. We identified specific prognostic factors for inferior long-term outcome; more intensive follow-up and treatment should be considered in patients with these characteristics.

Tibial anatomy in normal small breed dogs including anisometry of various extracapsular stabilizing suture attachment sites.

OBJECTIVES: To investigate proximal tibial anatomy and its influence on anisometry of extracapsular stabilizing sutures in small dog breeds. MATERIALS AND METHODS: Mediolateral radiographs of the femora, stifles, and tibiae of 12 small breed dogs were acquired with the stifles positioned at various angles. Measurements taken included tibial plateau angle (TPA), diaphyseal: proximal tibial angle (DPA), patellar tendon angle (PTA), Z-angle, relative tibial tuberosity width (rTTW), and the distance between six combinations of two femoral and three tibial extra-capsular stabilizing suture (ECS) attachment sites. Theoretical strain through stifle range-of-motion was recorded. RESULTS: The TPA (32° ± 5.8°), DPA (10.2° ± 7.3°), PTA (103.7° ± 6.2°), and Z-angle (70.4° ± 9.0°) were positively correlated with one another (R >0.7), but none were correlated with rTTW (0.93 ± 0.10). The F2-T1 combination of ECS attachment sites had lowest strain for nine stifles. The shortest attachment site separation was at a stifle flexion of 50° for nine stifles. Proximal tibial anatomy measurements could not predict optimal attachment site combination, optimal stifle angle for suture placement, or ECS strain. CLINICAL SIGNIFICANCE: There is individual variation in the optimal attachment site combination and stifle angle for suture placement, which may influence consistency of outcomes with ECS.

Expression of chimeric granulocyte-macrophage colony-stimulating factor/interleukin 2 receptors in human cytotoxic T lymphocyte clones results in granulocyte-macrophage colony-stimulating factor-dependent growth.

Adoptive immunotherapy with ex vivo-expanded antigen-specific cytotoxic T lymphocytes (CTLs) has been shown to clear viral infections and eliminate tumors in murine models. Clinical trials have also reported promising data for the use of adoptive immunotherapy to treat cytomegalovirus (CMV) and Epstein-Barr viral (EBV) infections in bone marrow transplant recipients. For these indications, the need for ex vivo-expanded CTLs is often short lived, until the immune system is reconstituted by the donor transplant. In chronic disease settings, increased longevity of adoptively transferred CTLs and generation of memory will be necessary. The additional administration of helper functions normally supplied by antigen-specific T helper (Th) cells will probably be essential for long-term survival of adoptively transferred CTLs. Toward this goal of supplying helper functions, we transduced human CTLs with chimeric GM-CSFR/IL-2R receptors that deliver an IL-2 signal on binding GM-CSF. Clones expressing the chimeric receptors proliferated in response to GM-CSF. Stimulation with antigen induced GM-CSF production and resulted in an autocrine growth loop such that the CTL clones proliferated in the absence of exogenous cytokines. This type of genetic modification has potential for increasing the circulating half-life and, by extension, the efficacy of ex vivo-expanded CTLs.

Identification of the nuclear transcription factor NFkappaB in rat after in vivo ethanol administration.

NFkappaB, a nuclear transcription factor, was induced in the brain nuclear fraction of naive rats after an acute injection of ethanol, 2 g/kg. In contrast, rats which had been chronically alcoholised showed the constitutively active NFkappaB-like complex only after a further acute dose of ethanol. Hepatic nuclear fractions did not exhibit the specific NFkappaB-like complex during the first 45 min after acute ethanol injection, beyond that which was normally constitutively present. Such activation of NFkappaB-like complex in the brains of the naive rats may play an important role in the cellular protective response.

Hypericin-induced photosensitization of HeLa cells leads to apoptosis or necrosis. Involvement of cytochrome c and procaspase-3 activation in the mechanism of apoptosis.

Here we report that photoactivated hypericin can induce either apoptosis or necrosis in HeLa cells. Under apoptotic conditions the cleavage of poly(ADP-ribose) polymerase (PARP) into the 85-kDa product is blocked by the caspase inhibitors benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk) and benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone (z-DEVD-fmk). Both inhibitors protect cells from apoptosis but cannot prevent hypericin-induced necrosis. Conversely, HeLa cells overexpressing the viral cytokine response modifier A (CrmA), which inhibits caspase-1 and -8, still undergo hypericin-induced apoptosis and necrosis. Evidence is provided for the release of mitochondrial cytochrome c in the cytosol and for procaspase-3 activation in the hypericin-induced cell killing.

Kelatorphan, a potent enkephalinases inhibitor, and opioid receptor agonists DAGO and DTLET, differentially modulate self-stimulation behaviour depending on the site of administration.

Endogenous enkephalins have been found in the perikaryon of the mesolimbic dopaminergic ventral tegmental area and in axonal terminals in the nucleus accumbens. To examine whether endogenous opioid peptides may modulate this mesolimbic system, injections of dopamine receptor agonists and antagonist, the mu-opioid receptor agonists DAGO and morphine, the delta-opioid receptor agonist DTLET and kelatorphan, a new potent inhibitor of multiple enkephalin-degrading enzymes, were performed into the lateral ventricle and into the nucleus accumbens. Intracranial self-stimulation behaviour, obtained through electrodes chronically implanted into the medial forebrain bundle in the posterolateral hypothalamus of the rat, was used as behavioural paradigm. Injections of kelatorphan and DTLET into the lateral ventricle both induced an ICI 174,864-reversible increased self-stimulation behaviour, a similar increase was observed after injection of d-amphetamine, while morphine and DAGO reduced the rate of self-stimulation. In contrast, the administration of kelatorphan or dopamine receptor agonists into the nucleus accumbens reduced the rate of intracranial self-stimulation, while DTLET was without effect, when injected into the same structure. Finally, intra-accumbens injections of DAGO produced a similar behavioural profile to that produced by intraventricular injections of the drugs. Opioids may thus differentially affect intracranial self-stimulation behaviour, as a function of the neuroanatomical locus of administration. Furthermore, these results suggest that kelatorphan may increase self-stimulation behaviour through an action at delta-opioid receptor, while DAGO and morphine may reduce self-stimulation behaviour through an action at mu-opioid receptors.

Inhibition of enkephalin metabolism and activation of mu- or delta-opioid receptors elicit opposite effects on reward and motility in the ventral mesencephalon.

The coexistence of endogenous opioid systems and dopaminergic neurones in the midbrain tegmental area suggests functional interactions between dopamine and enkephalins. Nevertheless, the identification of the specific opioid receptors associated with modulation of tegmental dopamine activity and its behavioural concomitants on motility and reward is far from clear, considering the mixed nature of the ligands usually employed. In this way, kelatorphan, a potent inhibitor of enkephalinases and selective agonists for mu- and delta-opioid receptor subtypes (DAGO and DSTBULET, respectively) were infused directly into the ventral tegmental area of the rat to study the role of endogenous enkephalins and opioid receptors in regulating spontaneous motor activity and intracranial self-stimulation behaviour. A greater increase in the rate of intracranial self-stimulation behaviour was found after activation of mu-opioid receptors in the ventral tegmental area, as compared to activation of delta-opioid receptors, whereas enhancement of endogenous enkephalins by inhibiting their metabolism through kelatorphan, reduced the rate of intracranial self-stimulation behaviour. On the contrary, spontaneous motor activity was reduced by the delta-opioid receptor agonist, whereas kelatorphan increased the movements of the animal. Taken together, these results show that inhibition of the metabolism of enkephalins in the ventral tegmental area decreased positive reinforcement from the lateral hypothalamic medial forebrain bundle and increased spontaneous movements. On the contrary, activation of both mu- or delta-opioid receptors in the ventral tegmental area significantly increased self-stimulation and decreased spontaneous motor activity, supporting the view that different mechanisms underlie the behavioural effects, resulting from enhancement of endogenous enkephalins and from activation of specific opioid receptors in the ventral mesencephalon.

Acetaldehyde-induced changes in monoamine and amino acid extracellular microdialysate content of the nucleus accumbens.

The effect of an acute intraperitoneal (i.p.) injection of acetaldehyde, 20 mg/kg or 100 mg/kg, on the microdialysate content of both amino acids and monoamines was studies in the nucleus accumbens (NA) by a microdialysis technique. Acetaldehyde, ACH, which was detectable at levels of 50-130 mumol/g brain tissue 10 min after injection, evoked a significant decrease in the extracellular microdialysis dopamine content, which was sustained for the period of the study, i.e. 120 min. Homovanillic acid, HVA, decreased significantly when the lower dose of ACH was administered while dihydrophenylacetic acid, DOPAC, showed no significant change with either dose of ACH during the period of the study. Serotonin levels decreased significantly after both doses of acetaldehyde, with significant increases of its major metabolite, hydroxyindolacetic acid, 5-HIAA, with the higher acetaldehyde dose. Taurine increased significantly, only during the first twenty minutes, after both doses of acetaldehyde, although neither of the excitatory amino acids assayed, glutamate and aspartate, nor the inhibitory amino acid, GABA, showed any significant changes. Acetaldehyde clearly evokes significant perturbation in the monoamine content of the NA, such changes being the converse to those reported for monoamines after ethanol administration, which might indicate a negative reinforcement effect.

Unchanged pressor effect of norepinephrine in normal man following the oral administration of two angiotensin converting enzyme inhibitors, captopril and HOE 498.

The norepinephrine - (50, 100 and 200 ng/kg per min) induced rise in blood pressure (BP) was determined in six health male volunteers following angiotensin converting enzyme (ACE) inhibition by either captopril (100 mg orally) or HOE 498 (10 mg orally). In terms of absolute BP measurements both compounds induced a reduction in basal and norepinephrine stimulated BP, whereas norepinephrine induced increments of BP above individual basal levels were unchanged by either converting enzyme inhibitor. It is concluded that attenuation of the pressor response to norepinephrine does not contribute to the hypotensive action of ACE inhibitors in healthy man.

Blood pressure and endocrine effects of single doses of CS-866, a novel angiotensin II antagonist, in salt-restricted hypertensive patients.

OBJECTIVE: This study was conducted to assess the dose-response relationship of the new angiotensin II (Ang II) antagonist CS-866 on blood pressure and on endocrine parameters in hypertensive patients with an activated renin-angiotensin system. DESIGN: Following a four-way crossover protocol, two groups of eight patients with mild-to-moderate hypertension received a sodium-restricted diet (60 mmol daily) and ingested single doses of 2.5, 10 and 40 mg or 5, 20 and 80 mg of CS-866, respectively, or placebo. Twenty-four hour ambulatory blood pressure measurements, plasma renin activity (PRA), Ang II and concentrations of RNH-6270, the pharmacologically active metabolite of CS-866, were monitored up to 24 h after medication. RESULTS: CS-866 was well tolerated. There was a significant decrease in 24 h diastolic blood pressure (DBP) at all doses of CS-866 above 5 mg. Increasing doses of CS-866 from 2.5 to 10 mg and from 5 to 20 mg lowered the mean 24 h DBP and DBP AUC(0-24h) values considerably more than increasing doses from 10 to 40 mg and from 20 to 80 mg, respectively. The mean 24 h DBP was lowered by 6.9 and 8.4 mmHg after oral doses of 10 and 20 mg CS-866, respectively, compared with placebo and by 8.9 mmHg after 80 mg CS-866. The drug increased PRA and Ang II concentrations in plasma, maximum concentrations of which occurred within 3 h post-dose. The highest RNH-6270 concentrations were also found at the first post-dose measurement 3 h after administration of CS-866. CONCLUSION: The new Ang II receptor antagonist CS-866 is effective and well tolerated. In salt-restricted hypertensive patients, CS-866 lowered blood pressure and increased PRA and Ang II concentrations at low doses. A single oral dose of 10-20 mg CS-866 resulted in almost maximal effects.

Resolution, absolute stereochemistry, and enantioselective activity of nomifensine and hexahydro-1H-indeno[1,2-b]pyridines.

Nomifensine and three selected compounds from the series of H4a,H5-trans,H4a,H9b-cis-2,3,4,4a,5,9b-hexahydro-1H-in deno[1,2-b]pyridines have been resolved into their enantiomers. All compounds exhibit pronounced enantioselective activity with respect to their inhibition of tetrabenazine-induced ptosis and potentiation of yohimbine toxicity. Nomifensine exhibits the same preference for one enantiomer with respect to dopamine and norepinephrine reuptake, whereas in the indeno[1,2-b]pyridine series in vitro experiments do not discriminate between the optical antipodes. The absolute stereochemistry of the pharmacologically active enantiomers in both series was determined by X-ray analyses and comparative CD spectra. For biological activity the diphenylmethane is an essential structure feature in both series. Its absolute configuration proved to be 4S for nomifensine and 5S for indenopyridines. The similar pharmacological profile of the two chemical entities is therefore reflected in an identical configuration of this pharmacologically important molecular part.