MECP2 truncating mutations cause histone H4 hyperacetylation in Rett syndrome

Rett syndrome (RTT) is a mostly sporadic disorder of developmental regression, with loss of speech and purposeful hand use, microcephaly and seizures. It affects 1 in 10 000-15 000 females. RTT is caused by mutations in the MECP2 gene, which is located in Xq28 and subject to X inactivation. MECP2 encodes a methyl-CpG-binding protein that binds to 5-methyl-cytosine in DNA through its methyl-binding domain. Recruitment of a transcriptional silencing complex through MeCP2's transcriptional repression domain results in histone deacetylation and chromatin condensation. To study the effects of two common truncating RTT mutations (R168X and 803delG), we examined mutant MeCP2 expression and global histone acetylation levels in clonal cell cultures from a female RTT patient with the mutant R168X allele on the active X chromosome, as well as in cells from a male hemizygous for the frameshift mutation 803delG (V288X). Both mutant alleles generated stable RNA transcripts, but no intact MeCP2 protein was detected with an antibody against the C-terminal region of MeCP2. Western blots with antibodies against acetylated histones H3 and H4 revealed that H4, but not H3, was hyperacetylated. By using antibodies against individual acetylated lysine residues, the observed H4 hyperacetylation was attributed to increased acetylation of lysine 16. Therefore, expression of endogenous truncating MECP2 alleles, in the absence of wild-type MeCP2 protein, is specifically associated with an increase in the mono-acetylated histone isoform H4K16. This observed effect may result in over-expression of MeCP2 target genes and, thus, play a role in the pathogenesis of RTT.

Treatment of acute colonic pseudoobstruction (Ogilvie's syndrome) with cisapride

A 73-yr-old white woman admitted with lobar pneumonia and congestive heart failure developed progressive colonic pseudoobstruction (Ogilvie's syndrome) 2 days after admission which was unrelieved by diatrizoate meglumine (Gastrografin, Squibb Canada, Montreal) enema and rectal tube. Cisapride, a new gastrointestinal prokinetic agent, was administered intravenously with full resolution of the syndrome. To the authors' knowledge, this is the first reported case of successful treatment of acute colonic pseudoobstruction with cisapride.

26-[125I]iodoponasterone A is a potent ecdysone and a sensitive radioligand for ecdysone receptors

The effects of ecdysone, the steroid molting hormone of arthropods, are of considerable interest both to insect physiologists and to those studying steroid-regulated gene expression. Yet progress in understanding ecdysone receptors has been inhibited by the lack of a suitable highly radioactive hormone analog with high affinity for the receptor. Here we report that the synthetic ecdysteroid 26-iodoponasterone A is one of the most active ecdysones known, inducing half-maximal morphological transformation in Drosophila Kc167 cells when present at 0.5 nM. 26-[125I]Iodoponasterone A can be prepared at a specific activity of 2175 Ci/mmol (1 Ci = 37 GBq) by reaction of the precursor 26-mesylinokosterone with carrier-free Na125I. The radiolabeled material binds to Kc167 cell ecdysone receptors specifically and with affinity (Kd ca. 3.8 X 10(-10) M). Thus, 26-[125I]iodoponasterone A appears to be a superior radioligand for ecdysone receptors on grounds both of affinity and of specific activity. Its ready availability should greatly facilitate studies of these receptors.

Cardiopulmonary dysfunction in cirrhosis

Cirrhosis is associated with several circulatory abnormalities. These include hyperkinetic systemic and splanchnic circulation, hepatopulmonary syndromes including pulmonary hypertension, and cirrhotic cardiomyopathy. Hepatopulmonary syndrome generally refers to hypoxaemia seen in patients with chronic liver disease and appears to be relatively common, although often subclinical. However, significant pulmonary hypertension occurs in 0.2-0.7% of cirrhotic patients. Nitric oxide and/or other vasodilators appear to be involved in the pathogenesis of hepatopulmonary syndrome through induction of pulmonary capillary dilatation which increases the alveolar-arterial oxygen gradient. Cirrhotic cardiomyopathy refers to abnormal left ventricular function which is manifested under conditions of physiological or pharmacological stress. The emergence of liver transplantation as an effective treatment for end-stage liver disease has led to recognition of previously subclinical cardiomyopathy and congestive heart failure accounts for significant morbidity and mortality after this procedure. Diminished myocardial beta-adrenergic receptor function has been shown to play an important role in the pathogenesis of this condition. The contributions of other factors including nitric oxide, catecholamines and membrane fluidity changes are under investigation. Cirrhotic patients also have an increased incidence of other cardiac abnormalities, such as endocarditis and pericardial effusions.

Phylogenetic relationships of Cheju horses to other horse breeds as determined by mtDNA D-loop sequence polymorphism

Historical records suggest that horses inhabiting the island of Cheju in Korea are descendants of Mongolian horses introduced in 1276. Other studies, however, suggest that horses may have been present on the island prior to the Mongolian introduction. To determine the origin of the Cheju horses we used a phylogenetic analysis of sequences of the mitochondrial DNA (mtDNA) D-loop region, including tRNA Pro and parts of tRNA thr and tRNA Phe sequences (1102-bp excluding the tandem repeat region). Maximum parsimony and neighbor-joining trees were constructed using sequences determined for seven Cheju, four Mongolian, one Przewalskii and two Chinese Yunnan horses, and published sequences for one Swedish and three Thoroughbred horses. Donkey mtDNA was used as an outgroup. We found that the mtDNA D-loop sequence varies considerably within Mongolian, Cheju and Thoroughbred horse breeds, and that Cheju horses clustered with Mongolian horses as well as with horses from other distantly related breeds. On the basis of these findings we propose that horses on Cheju Island are of mixed origin in their maternal lineage, and that horses may have existed and been traded on the island before the Mongolian introduction.

Patient volume per surgeon does not predict survival in adult level I trauma centers

BACKGROUND

The 1999 American College of Surgeons resources for optimal care document added the requirement that Level I trauma centers admit over 240 patients with Injury Severity Score (ISS) > 15 per year or that trauma surgeons care for at least 35 patients per year. The purpose of this study was to test the hypothesis that high volume of patients with ISS > 15 per individual trauma surgeon is associated with improved outcome.

METHODS

Data were obtained from the trauma registry of the five American College of Surgeons-verified adult Level I trauma centers in our mature trauma system between January 1, 1998, and March 31, 1999. Data abstracted included age, sex, Glasgow Coma Scale (GCS) score, intensive care unit length of stay, hospital length of stay, probability of survival (Ps), mechanism of injury, number of patients per each trauma surgeon and institution, and mortality. Multiple logistic regression was performed to select independent variables for modeling of survival.

RESULTS

From the five Level I centers there were 11,932 trauma patients in this time interval; of these, 1,754 patients (14.7%) with ISS > 15 were identified and used for analysis. Patients with ISS > 15 varied from 173 to 625 per institution; trauma surgeons varied from 8 to 25 per institution; per-surgeon patient volume varied from 0.8 to 96 per year. Logistic regression analysis revealed that the best independent predictors of survival were Ps, GCS score, age, mechanism of injury, and institutional volume (p < 0.01). Age and institutional volume correlated negatively with survival. Analysis of per-surgeon patient caseload added no additional predictive value (p = 0.44).

CONCLUSION

The significant independent predictors of survival in severely injured trauma patients are Ps, GCS score, age, mechanism of injury, and institutional volume. We found no statistically meaningful contribution to the prediction of survival on the basis of per-surgeon patient volume. Since this volume criterion for surgeon enpanelment and trauma center designation would not be expected to improve outcome, such a requirement should be justified by other measures or abandoned.

Antibiotic-impregnated autogenic cancellous bone grafting is an effective and safe method for the management of small infected tibial defects: a comparison study

OBJECTIVE

Bone grafting plays an important role in reconstructing infected tibial nonunions. The effects of antibiotic-impregnated bone grafting in infection elimination and bone incorporation was reported in this retrospective study.

METHODS

Ninety-six patients treated for infected tibial nonunions were evaluated. These patients were managed with local antibiotic bead therapy and staged antibiotic-impregnated autogenous cancellous bone graft or pure autogenous cancellous bone graft. Patients were randomized to antibiotic-impregnated bone grafting or bone grafting-only groups on the basis of whether the admission date was odd or even. Patients were divided into two groups (antibiotic-impregnated bone grafting group and pure cancellous bone grafting group), according to the procedure used in preparing the bone grafts. The antibiotic-impregnated bone grafting group included 37 men and 9 women whose average age was 36 years (range, 17 to 72 years). The average follow-up period was 4.8 years. By using the Cierny-Mader staging classification of chronic osteomyelitis, 32 of 46 patients (70%) were stage 4A, and 14 of 36 patients (30%) were stage 4B. The pure cancellous bone grafting group included 39 men and 11 women whose average age was 37 years (range, 18 to 72 years). The average follow-up period was 4.5 years (range, 4 to 6 years). Thirty-nine of 50 patients (78%) were stage 4A, and 11 of 50 patients (22%) were stage 4B. The bone defects in both groups ranged from 2 to 4 cm.

RESULTS

Wound healing and bony union were achieved in the antibiotic-impregnated bone grafting group. Only two patients had recurrent infections. The infection arrest rate was 95.6%. However, 9 of 50 patients in the pure cancellous bone grafting group had recurrent infections. The infection arrest rate was 82%. The antibiotic-impregnated bone grafting group had significantly superior results (95.6% vs. 82% chi2 test, p < 0.05) in infection elimination than the pure cancellous bone grafting group.

CONCLUSION

After 4 to 6 years of follow-up, our results suggest that the use of impregnating antibiotics have no adverse effects on autogenic cancellous bone graft incorporation and could help to eliminate infection effectively.

Effects of altered cardiac membrane fluidity on beta-adrenergic receptor signalling in rats with cirrhotic cardiomyopathy

BACKGROUND/AIMS

The relationship between cardiac plasma membrane physical properties and beta-adrenergic receptor signalling function in cirrhotic cardiomyopathy remains unclear. We aimed to clarify this issue by examining the effect of altering membrane fluidity on beta-adrenergic receptor signalling in cirrhotic rats.

METHODS

Cirrhosis was induced by chronic bile duct ligation, while controls were sham-operated. Left ventricular papillary muscle contractility was measured in an organ bath containing 95% oxygen saturated Tyrode's buffer. Cardiac plasma membrane physical properties, represented by membrane fluidity, were evaluated by fluorescent depolarization, using 1,6-diphenyl-1,3,5,-hexatriene as a probe. Membrane cAMP levels were measured after stimulation at the beta-adrenoceptor level by isoproterenol (10(-4) mol/l), the G-protein level with AIF(-4) (10 mmol/l) and the adenylyl cyclase level with forskolin (100 micromol/l) before and after membrane fluidization with 2-(2-methoxyethoxy)ethyl 8-(cis-2-n-octylcyclopropyl)octanoate (A2C).

RESULTS

Maximum papillary muscle contractile force under isoproterenol stimulation was 0.48+/-0.05 and 0.34+/-0.03 N/cm2 in sham-operated and bile duct ligated rats, respectively (p<0.05). Cardiac membranes from cirrhosis were rigid and this was associated with diminished cAMP generation. After the fluidity of membranes from cirrhotic rats was restored to control values with A2C, cAMP production stimulated with isoproterenol was significantly increased. However, cAMP production stimulated by AIF(-4) and forskolin did not differ before and after membrane fluidization.

CONCLUSIONS

The blunted cardiac contractility of cirrhosis was associated with decreased membrane fluidity and diminished beta-adrenergic receptor signalling. The results suggest that in cirrhotic cardiomyopathy, the rigid plasma membrane interferes with the beta-adrenoceptor and G-protein coupling process.

Study of the gastrointestinal protective effects of polysaccharides from Angelica sinensis in rats

We studied the protective effects of polysaccharides isolated from the root of Angelica sinensis (Oliv.) (Danggui) on gastrointestinal damage induced by ethanol or indomethacin in rats. Oral administration of ethanol provoked a marked hemorrhagic damage in the glandular mucosa, which was accompanied with a significant increase of myeloperoxidase (MPO) activity, a marker enzyme for inflammation and neutrophil infiltration. An extract from Angelica, which mainly consisted of polysaccharides (95%) (AP), dose-dependently prevented gastric mucosal damage. This ulcer protective effect could last at least 12 h after administration. Prostaglandin E2 produced a similar anti-lesion effect. AP and prostaglandin E2 also reduced mucosal MPO activity. Indomethacin-induced gastrointestinal damage, another neutrophil-dependent lesion model in the gastrointestinal tract, was also prevented by AP pretreatment. The present findings suggest that polysaccharides from Angelica possess an anti-inflammatory action, perhaps through the inhibitory action on neutrophil infiltration in the gastrointestinal mucosa. AP could potentially be useful to prevent any neutrophil-dependent mucosal injury in the gastrointestinal tract.

Molecular cloning and localization of human syntaxin 16, a member of the syntaxin family of SNARE proteins

We have cloned a new member of the syntaxin family of proteins, designated human syntaxin 16 (hsyn16). The open reading frame encodes a polypeptide of 307 amino acids with potential coiled-coil domains and a carboxy-terminal hydrophobic tail, which is characteristic of other members of the syntaxin family. The encoded polypeptide bears sequence homology to known syntaxin molecules. Northern blot analysis revealed a single transcript that is fairly ubiquitous, being slightly more enriched in heart and pancreas. Indirect immunofluorescence localised myc-tagged hsyn16 (myc-hsyn16) to the Golgi apparatus, colocalizing well with lens culinaris agglutinin, an established Golgi marker, as well as with other Golgi SNAREs such as GS28 and syntaxin 5. Myc-hsyn16 is redistributed to the endoplasmic reticulum upon brefeldin A treatment, indicating that it is localised to the Golgi stack. The ubiquitous expression and Golgi localization of hsy16 suggest that it is involved in a vesicular transport step within the organelle.

Growth of Diamond from Atomic Hydrogen and a Supersonic Free Jet of Methyl Radicals

The growth of small ( approximately 10-micrometer) diamond particles (on 0.1-or 0.25-micrometer seed crystals) using an effusive glow discharge nozzle for H.and a separate supersonic pyrolysis jet for .CH(3) is reported. Laser micro-Raman, scanning electron microscopy, and x-ray photoelectron spectroscopy data are presented as evidence that well-crystallized diamond is indeed formed. Resonant multiphoton ionization spectroscopy is used as a diagnostic for the gas-phase chemistry indicating that the radical sources are clean and quantitative and that there is no detectable interconversion of .CH(3) to C(2)H(2) under the conditions of the experiment. Diamond growth is found at substrate temperatures greater than or equal to 650 degrees C with no marked increase in the rate of growth up to 850 degrees C. Acetylene does not give good quality diamond under similar conditions.

Beneficial hemodynamic effects of ketanserin in patients with cirrhosis: possible role of serotonergic mechanisms in portal hypertension

We studied the acute effects of ketanserin, a serotonin S2 antagonist, on systemic and splanchnic hemodynamics in 11 patients with cirrhosis. Mean arterial pressure decreased moderately but significantly after ketanserin. This effect was maximal at 5 min and correlated to the severity of cirrhosis. Cardiac index and systemic vascular resistance were not significantly changed. The hepatic venous pressure gradient, used as an index of portal pressure, significantly decreased after ketanserin (-23%). Azygos blood flow, a reflection of superior portosystemic collateral blood flow, also significantly decreased (-26%), but this effect was delayed, progressive and not correlated to the arterial pressure decrease. Hepatic blood flow was unchanged. These findings suggest that the systemic and splanchnic circulations may be hypersensitive to ketanserin in cirrhotic patients, and that serotonergic mechanisms may contribute to maintain portal hypertension. New specific antiserotonergic drugs deserve further evaluation for potential therapeutic implications in portal hypertension.

Roles of phosphatidylinositol 3-kinase and Rac in the nuclear signaling by tumor necrosis factor-alpha in rat-2 fibroblasts

We investigated the extent to which phosphatidylinositol 3-kinase (PI 3-kinase) and Rac, a member of the Rho family of small GTPases, are involved in the signaling cascade triggered by tumor necrosis factor (TNF)-alpha leading to activation of c-fos serum response element (SRE) and c-Jun amino-terminal kinase (JNK) in Rat-2 fibroblasts. Inhibition of PI 3-kinase by LY294002 or wortmannin, two specific PI 3-kinase antagonists, or co-transfection with a dominant negative mutant of PI 3-kinase dose-dependently blocked stimulation of c-fos SRE by TNF-alpha. Similarly, LY294002 significantly diminished TNF-alpha-induced activation of JNK, suggesting that nuclear signaling triggered by TNF-alpha is dependent on PI 3-kinase-mediated activation of both c-fos SRE and JNK. We also found nuclear signaling by TNF-alpha to be Rac-dependent, as demonstrated by the inhibitory effect of transient co-transfection with a dominant negative Rac mutant, RacN17. Our findings suggest that Rac is situated downstream of PI 3-kinase in the TNF-alpha signaling pathway to the nucleus, and we conclude that PI 3-kinase and Rac each plays a pivotal role in the nuclear signaling cascade triggered by TNF-alpha.

Retropharyngeal abscess: epiglottitis of the new millennium

From 1993 through 1999, 26 children with retropharyngeal abscess and 2 children with acute epiglottitis were cared for by pediatric otolaryngologists in northern Virginia. Fever, sore throat, dysphagia, refusal to swallow, dysphonia, drooling, and neck extension are common presenting signs and symptoms in acute epiglottitis and in retropharyngeal abscess. Contrast-enhanced computed tomography of the oropharynx was performed in all cases and was the most helpful diagnostic test.

Rapid typing of apolipoprotein B DNA polymorphisms by DNA amplification. Association between Ag epitopes of human apolipoprotein B-100, a signal peptide insertion/deletion polymorphism, and a 3'flanking DNA variable number of tandem repeats polymorphism of the apolipoprotein B gene

We present here rapid and efficient methods for the analysis of multiple variable apolipoprotein (apo) B loci using polymerase chain reaction based techniques. For illustrative purposes, we have applied these methods to establish an association between these polymorphisms and the apo B Ag immunological epitopes. The 5 DNA polymorphisms include 3 restriction endonuclease sites (for XbaI, EcoRI and MspI), a variable number of tandem repeat (VNTR) locus at the 3' end of the apo B gene, and an insertion/deletion polymorphism involving the signal peptide region of apo B. The latter two newly described polymorphisms are directly detectable following amplification and may have physiological effects on apo B expression because of their critical locations. All of these sites were typed using flanking oligonucleotides and the newly developed polymerase chain reaction. Amplification products were typed either directly (3' VNTR and signal peptide insertion/deletion alleles), or following specific enzyme digestion (for the restriction sites), or by allele specific oligonucleotides. The detailed methods presented will prove generally useful for rapidly typing DNA variation in the apo B gene. Using these techniques, we found a significant linkage disequilibrium between the Ag(t/z) locus and the 3' VNTR, and the Ag(c/g) locus and the signal peptide length polymorphism. Future association studies using these DNA polymorphisms should take into consideration that observed effects may be related to its linkage disequilibrium with the Ag loci and vice versa.

Endoscopic removal of biliary self-expandable metallic stents: a prospective study

BACKGROUND AND STUDY AIMS

The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs.

PATIENTS AND METHODS

30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session.

RESULTS

The covered SEMSs were easily removed in 19 out of 22 patients (86.4 %), whereas none of the eight uncovered SEMSs (0 %) could be removed. The only factor predicting successful stent removal was the presence of a stent covering ( P = 0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents.

CONCLUSIONS

In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.

Suppression of mouse skin tumor promotion and induction of apoptosis in HL-60 cells by Alpinia oxyphylla Miquel (Zingiberaceae)

There have been considerable efforts to search for naturally occurring substances for the intervention of carcinogenesis. Many components from dietary or medicinal plants have been identified that possess substantial chemopreventive properties. An example is curcumin (Curcuma longa Linn., Zingiberaceae), which has been shown to inhibit tumor promotion in experimental carcinogenesis. Alpinia oxyphylla Miquel, another plant of the ginger family used in oriental herbal medicine, contains diarylheptanoids whose structures are analogous to that of curcumin. In the present study, we have tested A.oxyphylla for its ability to suppress tumor promotion. Thus, topical application of the methanolic extract of dried fruits of A.oxyphylla significantly ameliorated 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin tumor promotion as well as ear edema in female ICR mice. In another study, treatment of HL-60 cells with the methanolic extract of A.oxyphylla significantly reduced the viability of the cells and also inhibited DNA synthesis. Microscopic examination of the treated cells showed characteristic morphology of apoptosis. Furthermore, cells treated with the extract of A.oxyphylla exhibited internucleosomal DNA fragmentation in time- and concentration-dependent manners. TPA-stimulated generation of superoxide anion in differentiated HL-60 cells was also blunted by A.oxyphylla. Taken together, these findings suggest that A.oxyphylla possesses potential chemopreventive and antitumorigenic activities.

Lymphocyte subpopulation reference ranges for monitoring human immunodeficiency virus-infected Chinese adults

Two hundred eight healthy human immunodeficiency virus (HIV) type 1- and HIV type 2-seronegative Chinese adults (78 males and 130 females; mean age, 32 years; age range, 18 to 71 years) were analyzed for lymphocyte subsets by a standardized and quality-controlled flow cytometric immunophenotyping technique. While the leukocyte differential values were comparable to those found in studies of Caucasians, the means, medians, and 95% reference ranges of lymphocyte subsets were very different. The 95% reference ranges in absolute counts per microliter of whole blood (percentage of lymphocytes) for CD3+, CD3+ CD4+, CD3+ CD8+, CD3- CD19+ (B), and CD3- with CD16+ and/or CD56+ (NK) cells were 672 to 2,368 (54.8 to 83.0%), 292 to 1,366 (23.1 to 51.0%), 240 to 1,028 (17.9 to 47.5%), 82 to 560 (5.1 to 20.8%), and 130 to 938 (7.1 to 38.0%), respectively. CD3+ CD4+ cells showed significant sex difference (for males, mean of 702 [34.8%] and standard deviation of 258 [7.5%]; for females, mean of 728 [37.3%] and standard deviation of 254 [7.4%]) as well as an increase with age of 42 (1.6%) per decade. Investigations of the NK cell population did not show similar findings. Classification of HIV disease, treatment, and prophylactic regimens based on studies which relied heavily on estimations of lymphocyte subsets alone should be used with special caution for Chinese patients. Provided that adequate quality control measures are taken to ensure comparability of data, we recommend that these ranges be used on a day-to-day basis in laboratories that have not yet established their own reference ranges.

Basaloid squamous carcinoma of the oesophagus: a distinct neoplasm with multipotential differentiation

AIMS

Basaloid squamous carcinoma (BSC) is an uncommon variant of squamous cell carcinoma, with its prevalent sites being the hypopharynx, tongue base and larynx. In the oesophagus, BSC is rarer than in the head and neck region. This study was aimed to document the clinicopathological features of BSCs of the oesophagus, and to present their relative incidence and immunohistochemical findings.

METHODS AND RESULTS

Eighteen cases of BSC of the oesophagus, comprising 3.6% of 502 oesophageal carcinomas, were reviewed for their pathological and clinical features, and examined for the immunohistochemical expression of neuroendocrine markers, cytokeratins, p53, pRb and bcl-2. Oesophageal basaloid squamous carcinomas tended to be biphasic or multiphasic carcinomas, most commonly with basaloid and squamous components (eight cases), or with additional adenocarcinoma (three cases) or with small cell carcinoma (two cases). Each component was microscopically clearly distinguishable from the others, and metastasized separately, chiefly the basaloid component. The remaining five cases were apparently pure basaloid carcinomas, being characterized by lobules and nests of monotonous round undifferentiated cells with frequent comedo necrosis. They resembled, but were differentiated from, the small cell carcinoma on the basis of neuroendocrine markers and cytokeratin expression. p53, pRb and bcl-2 oncoprotein, which are known to normally present in the basal/parabasal cells of the oesophageal epithelium, were detected in 40-50% of cases, with a heterogeneous expression pattern. The patients were all male, with the age ranging 47-74 years (median 57) and presented at variable stages. The plotted 3 years survival rate was 51%, and the immunohistochemical expression of p53, pRb and bcl-2 was not related to the survival of the patients.

CONCLUSION

Basaloid squamous carcinoma of the oesophagus is a peculiar neoplasm with a capacity of multidirectional differentiation, often with heterogeneous oncogene expression, probably reflecting the pluripotential stem cell origin.

Putaminal petechial haemorrhage as the cause of chorea: a neuroimaging study

OBJECTIVES

A hyperintense putamen on either CT or MRI as a finding associated with chorea has occasionally been described and is almost always associated with non-ketotic hyperglycaemia. The cause of the hyperintensity of the striatum in these images is still controversial. Some reports have found that calcification was responsible whereas others have advocated petechial haemorrhage as the cause. The purpose of this study was to determine whether hyperintense striata are caused by petechial haemorrhage or calcification, with the sequential imaging changes.

SUBJECTS AND METHODS

Five patients presenting with an acute onset of either hemichorea or generalised chorea and showed either unilateral or bilateral hyperdense striatum on the initial CT were assessed. Neuroimaging studies including sequential CT and MRI examinations and detailed biochemical tests were performed.

RESULTS

Three patients had pronounced hyperglycaemia and the other two patients had no biochemical abnormalities. In all patients, the first CT scans, performed within two weeks of the onset of chorea, showed a high density over the striatum contralateral to the chorea, which diminished or disappeared two months later. T1 weighted imaging disclosed hypersignal intensities over the striatum contralateral to the chorea on admission which diminished two months later. T2 weighted imaging at two months showed hyposignal intensity changes corresponding to the area with hypersignal changes on T1 weighted images, implying haemosiderin deposition.

CONCLUSION

Based on the evolution of clinical manifestations and the findings of neuroimaging, putaminal petechial haemorrhage might be a new entity causing either hemichorea or generalised chorea.

Anti-tumor promoting potential of naturally occurring diarylheptanoids structurally related to curcumin

In recent years, there have been considerable efforts to search for naturally occurring substances for intervention of carcinogenesis. Many components from medicinal or dietary plants have been identified to possess potential chemopreventive properties. For instance, curcumin, a yellow colouring agent from turmeric (Curcuma longa Linn., Zingiberaceae) has been shown to inhibit tumor formation in diverse animal models. Alpinia oxyphylla Miquel that also belongs to ginger family has been used in oriental herbal medicine. In the present work, we have evaluated the anti-tumor promoting potential of yakuchinone A (1-[4'-hydroxy-3'-methoxyphenyl]-7-phenyl-3-heptanone) and yakuchinone B (1-[4'-hydroxy-3'-methoxyphenyl]-7-phenylhept-1-en-3-one), major pungent ingredients of A. oxyphylla. Thus, topical application of yakuchinone A or B significantly suppressed TPA-induced epidermal ornithine decarboxylase activity. They also reduced TPA-stimulated production of tumor necrosis factor-alpha in cultured human promyelocytic leukemia (HL-60) cells. Both compounds blunted the TPA-induced superoxide generation in differentiated HL-60 cells in a concentration-related manner and also inhibited lipid peroxidation in rat brain homogenates. Furthermore, yakuchinone A and yakuchinone B nullified the activation of the activator protein-1 (AP-1) in immortalized mouse fibroblast cells in culture. These findings indicate that pungent diarylheptanoids from A. oxyphylla have anti-tumor promotional properties that can contribute to their chemopreventive potential.