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BACKGROUND AND PURPOSE: Progressive multifocal leukoencephalopathy (PML) represents a life-threatening demyelinating disorder of the brain caused by reactivation of a rare opportunistic infection with JC Polyomavirus. The aims of this study were to describe the incidence of a susceptibility-weighted imaging hypointense rim in patients with multifocal leukoencephalopathy and to explore the histologic correlates and prognostic value of the rim with regard to the clinical outcome. MATERIALS AND METHODS: This retrospective study included 18 patients with a definite diagnosis of progressive multifocal leukoencephalopathy. Ten patients were HIV-positive, 3 patients had natalizumab-associated progressive multifocal leukoencephalopathy, 1 patient had multiple myeloma, 3 patients had a history of lymphoma, and 1 was diagnosed with acute myeloid leukemia. Patients were divided into short- (up to 12 months) and long-term (>12 months) survivors. A total of 93 initial and follow-up MR imaging examinations were reviewed. On SWI, the presence and development of a hypointense rim at the periphery of the progressive multifocal leukoencephalopathy lesions were noted. A postmortem histologic examination was performed in 2 patients: A rim formed in one, and in one, there was no rim. RESULTS: A total of 73 progressive multifocal leukoencephalopathy lesions were observed. In 13 (72.2%) patients, a well-defined thin, linear, hypointense rim at the periphery of the lesion toward the cortical side was present, while in 5 (27.8%) patients, it was completely absent. All 11 long-term survivors and 2 short-term survivors presented with a prominent SWI-hypointense rim, while 5/7 short-term survivors did not have this rim. CONCLUSIONS: The thin, uniformly linear, gyriform SWI-hypointense rim in the paralesional U-fibers in patients with definite progressive multifocal leukoencephalopathy might represent an end-point stage of the neuroinflammatory process in long-term survivors.

BackgroundDiagnosis of idiopathic inflammatory myopathies (IIM) represents a clinical challenge and muscle biopsy itself is regarded as the cornerstone for confirming diagnosis of IIM. However, the significance of muscle biopsy as diagnostical tool remains inconclusiveObjectivesTo determine the diagnostic accuracy and clinical relevance of muscle biopsy in patients with suspected myositis.MethodsIn this retrospective cohort study, histopathological findings of muscle biopsy specimens of adult (≥ 18 years of age) patients with clinically suspected or differential diagnosis of myositis referred from all over Austria to the Medical University of Vienna through the period of 01.01.2007-31.10.2021 were analyzed. Following information were extracted from handwritten assignment sheets: referral department, suspected diagnosis (inflammatory and/or non-inflammatory myopathy), sampling location, demographic, clinical, laboratory and serologic data, and imaging results.Histological findings were grouped in: 1) inflammatory, 2) non-inflammatory (neurogenic, metabolic etc.), 3) inflammatory and non-inflammatory mixed, and 4) normal. Clinical information on start of immunosuppressive treatment after muscle biopsy could be partly retrieved form electronical medical records (EMR). Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of histological results were calculated using clinical diagnosis (defined as initiation of immunosuppressive therapy) as gold standard.Results778 muscle biopsy specimens of 762 patients with suspected myositis (49.6% female, mean age of 56 years) were analyzed. Cohort descriptives are displayed in Table 1.Overall, 373/778 (47.9%) muscle biopsies revealed inflammatory features only or had mixed results with non-inflammatory characteristics. Out of 541 samples with suspected diagnosis of myositis, diagnosis was confirmed histologically in 300 (55.5%) cases; 46 (8.5%) specimens additionally showed co-features of non-inflammatory myopathy, whereas 221 (40.3%) were non-inflammatory at all and 15 (2.8%) were normal. Proportion of myositis was more pronounced, when CK was elevated at time of biopsy (Figure 1).Figure 1.From suspicion to histological verification depending on CK-levelsOut of 237 samples with differential diagnosis of non-inflammatory myopathy in addition to myositis, 53 (22.4%) were histology. confirmed as inflammatory only and 20 (8.4%) showed mixed features. 153 (64.6%) biopsies were non-inflammatory only and 8 (3.4%) normal. Samples with no pathological features were observed in 24/778 (2.3%) of the cases, with 0.8% sampling error (no muscle tissue).Of 421/778 (54.1%) patients, clinical data could be extracted from EMR of which 209/421 (49.6%) had histological features of inflammation. In 287/421 (68%) cases, information regarding initiation of immunosuppressive treatment were available on EMR. 224/287 (78%) patients received immunosuppression (steroids and/or disease-modifying anti-rheumatic drug [DMARD]), thus fulfilled clinical diagnosis of myositis. In 155/224 (69.2%) cases, muscle biopsy confirmed histology. features of inflammation. Tests on diagnostic accuracy of muscle biopsy using initiation of any immunosuppressive treatment as gold standard were performed. The sensitivity of the test (biopsy) for diagnosing IIM was 71.4% with a specificity of 79.6%. PPV was high (92.8%), whereas NPV low (43.1%).ConclusionLess than 50% of biopsy samples with suspected diagnosis of myositis histologically revealed an inflammatory myopathy. The percentage increased when CK levels were elevated. Sensitivity and specificity of muscle biopsy was moderate, when using start of immunosuppressive therapy as gold standard for IIM diagnosis.References[1]Tanboon, J. & Nishino, I. Classification of idiopathic inflammatory myopathies: pathology perspectives. Curr. Opin. Neurol. 32, 704–714 (2019)Disclosure of InterestsNone declared

Genetic discoveries of Alzheimer’s disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer’s disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer’s disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer’s disease. © 2021, The Author(s).

Background: PSP is a neuropathologically defined disease entity. Clinical diagnostic criteria, published in 1996 by the National Institute of Neurological Disorders and Stroke/Society for PSP, have excellent specificity, but their sensitivity is limited for variant PSP syndromes with presentations other than Richardson's syndrome. Objective: We aimed to provide an evidence- and consensus-based revision of the clinical diagnostic criteria for PSP. Methods: We searched the PubMed, Cochrane, Medline, and PSYCInfo databases for articles published in English since 1996, using postmortem diagnosis or highly specific clinical criteria as the diagnostic standard. Second, we generated retrospective standardized clinical data from patients with autopsy-confirmed PSP and control diseases. On this basis, diagnostic criteria were drafted, optimized in two modified Delphi evaluations, submitted to structured discussions with consensus procedures during a 2-day meeting, and refined in three further Delphi rounds. Results: Defined clinical, imaging, laboratory, and genetic findings serve as mandatory basic features, mandatory exclusion criteria, or context-dependent exclusion criteria. We identified four functional domains (ocular motor dysfunction, postural instability, akinesia, and cognitive dysfunction) as clinical predictors of PSP. Within each of these domains, we propose three clinical features that contribute different levels of diagnostic certainty. Specific combinations of these features define the diagnostic criteria, stratified by three degrees of diagnostic certainty (probable PSP, possible PSP, and suggestive of PSP). Clinical clues and imaging findings represent supportive features. Conclusions: Here, we present new criteria aimed to optimize early, sensitive, and specific clinical diagnosis of PSP on the basis of currently available evidence. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society

Dementia, Alzheimer's disease (AD) being the most common cause of it, is a major and growing medical and social problem, particularly in the advanced age, with the highest rate in the population over 75 y. Recent sophisticated therapeutic measures require more sensitive diagnostic tests to recognize early stages of the disease. In this paper, the current neuronuclear imaging literature is reviewed with regard to early and differential diagnosis of dementia. Functional imaging with single photon emission computed tomography (SPECT) and positron emission tomography (PET) could provide the clinician with additional information complementary to morphological assessments, thus contributing to achieve a more adequate diagnosis, and also with information regarding prodromal stages of AD.

The feasibility of using the Mitsunobu reaction for coupling of purines with steroids to obtain nucleosteroids was investigated in the particular case of 6-chloropurine and cholesterol. Three principal products were obtained: 3βbT-(6-chloropurin-9-yl)-5-cholestene (1), 3α-(6-chloropurin-9-yl)-5-cholestene (2), and 6βbT-(6-chloropurin-9-yl)-3,5-cyclocholestane (3), isolated with 10.5%, 22.7%, and 12.6% yield, respectively. The stereochemical and structural diversity of the coupling products are explained by the formation of a homoallylic carbocation through participation of the double bond of cholesterol.

The reaction of acetylaminoacetonitrile with penta-O-benzoyl-α-D-glucopyranose in dichloromethane-nitromethane, in a 1:1 stoichiometric proportion, catalysed by stannic chloride, gave a nitrilium salt that, after hydrolysis, afforded the corresponding N-acyl glycosylamine and a mixture of several compounds originating from different competitive reactions. Among these compounds, N-benzoyl-3,5,6-tri-O-benzoyl-β-D-glucofuranosyl amine, tetra-O-benzoyl-D-glucopyranose, and octa-O-benzoyl-β-D-glucopyranosyl-(1→1)-α-D-glucopyranoside (octa-O-benzoyl-α,β-trehalose) were identified.

The reaction of mono- and diethanolamine with a 6-chloropurinyl inositol gave 6-ethanolaminopurinyl-inositol derivatives which by reaction with thionyl chloride generated, through quaternization of N of the purine, condensed imidazo-purinyl carbocyclic nucleoside analogs.

In definite Creutzfeldt-Jakob disease (CJD), morphological and immunohistochemical patterns are useful to identify molecular subtypes. Severe cerebellar pathology and hippocampal involvement helps to identify VV subtypes. The rare VV1 variant (1%), more frequent in young individuals, is additionally characterized by the presence of ballooned neurones in affected areas. In 1985, Cartier et al. described a family cluster of three individuals with an ataxic CJD form, showing, in addition to severe cerebellar and hippocampal involvement, the presence of frequent Hirano bodies (HB) in CA1 pyramidal neurones. HB are frequently found in aged individuals with Alzheimer pathology although they are not a specific finding.In this study, we evaluated the presence of HB in hippocampi of 54 genetically and molecularly characterized CJD cases, aiming to elucidate whether additional morphological features could be helpful to point to molecular subtypes.We identified nine cases (four VV1, one out of three MV2K, three out of six MV2K+2C and one MV carrying a 96-base pair insertion) with abundant, partly bizarre and clustered HB in CA1 sector, not observed in other subtypes. The presence of HB was independent of hippocampal involvement by the disease itself.Clusters of abundant HB might be found in rare CJD subtypes such as VV1, MV2K/MV2K+2C and some genetic cases. In addition to histopathological and PrP immunohistochemical deposition patterns, their presence might be a useful additional morphologic feature that could point to the molecular subtype, especially when genetic and/or Western blot analyses are not available.

Several carbocyclic nucleoside analogs possessing a 6-substituted purine linked to a mesylated muco-inositol were synthesized. The coupling of triethylamine-activated 6-chloropurine with 2,3-anhydro-l,5,6-tri-O-(methanesulfonyl)-epi-inositol gave a 6-chloro purinyl muco-inositol amenable to further synthetic transformations in the heterocyclic moiety by substitution of the chlorine atom by nitrogen nucleophiles such as methylamino, diethylamino, benzylamino, hydrazino, morpholino, hydroxylamino, piperidino, and glycyl groups.

The reaction of acetylaminoacetonitrile with penta-O-benzoyl-α-D-glucopyranose in dichloromethane-nitromethane, in a 1:1 stoichiometric proportion, catalysed by stannic chloride, gave a nitrilium salt that, after hydrolysis, afforded the corresponding N-acyl glycosylamine and a mixture of several compounds originating from different competitive reactions. Among these compounds, N-benzoyl-3,5,6-tri-O-benzoyl-β-D-glucofuranosyl amine, tetra-O-benzoyl-D-glucopyranose, and octa-O-benzoyl-β-D-glucopyranosyl-(1→1)-α-D-glucopyranoside (octa-O-benzoyl-α,β-trehalose) were identified.

Starting from a mesylated inosamine several ethanol-, β - chloroethyl-, β-mesyloxy ethyl-, and β-iodoethylamino compounds were synthesized. Different chlorinated derivatives were obtained through variations in the chlorinating reagent, solvent, and reaction time.

Several nucleocyclitols were synthesized in good yield from an inositol epoxide and some activated purine derivatives (adenine, 6-methylmercaptopurine). The reaction was also carried out with other more basic, nitrogen heterocycles such as imidazole and piperidine, although side reactions can then became significant.

Steroidal nucleoside analogs were synthesized starting from testosterone. By reduction of the oxime of 17 beta-hydroxy-androst-4-en-3-one (testosterone), a mixture of the two amino epimers of C-3 were obtained. The 3 alpha-amino-androst-4-en-17 beta-ol was crystallized in 73% yield and coupled with 5-amino-4,6-dichloropyrimidine to give 3 alpha-(5'-amino-4'-chloro-pyrimidin-6'-yl)amino-androst-4-en-17 beta-ol. This compound was treated with triethyl orthoformate in acid media to give the corresponding purinyl steroid adduct 3 alpha-(6'-chloro-purin-9'-yl)-androst-4-en-17 beta-ol in 98% yield. This substance, in turn, was converted with good yield into the 6'-thio, 6'-methylamino, and 6'-diethyl aminopurinyl derivatives through nucleophilic reactions at C-6 of the purine nucleus.

Question: To investigate the features of sympathetic skin response in patients with amyotrophic lateral sclerosis (ALS) and determine a possible involvement of the autonomic nervous system in ALS. Methods: The data of outpatients and inpatients with definite ALS were collected in Peking Union Medical College Hospital from Jun, 2009 to Jun, 2012.Standard sensory and motor nerve conduction was performed in median nerve, ulnar nerve and tibial nerve in 95 patients with ALS. F-wave and sympathetic skin response were measured in median nerve. Parameters analyses mainly included sensory conduction velocity and amplitude, distal motor latency (DML), compound muscle action potential (CMAP) amplitude, SSR latency and amplitude. Findings were compared with those in 50 normal controls. Results: The SSR was present in 100% of the controls but was absent in 5.3% in the hands and12.6% in the feet in ALS patients. The mean amplitudes of the ALS patients (palmar SSR: 1.26±0.78 mv; plantar SSR: 0.76±0.66 mv) were lower than that of the controls (palmar SSR: 3.31±2.15 mv; plantar SSR: 1.73±0.98 mv) (P 0.05). The abnormality rate of SSR was 35.8% in 95 ALS patients, 13.5% in the hands, 35.8% in the legs. The abnormality of the plantar SSR is higher than that of the palmar SSR (P

In 1981, an unknown disease appeared in Spain, the Spanish Toxic Oil Syndrome. Nowadays and despite all efforts, the etiological agent is still unknown. Early studies showed a link between this illness and the consumption of denatured rapeseed oil fraudulently processed and marketed as edible oil. Two families of aniline derivatives present in these oils (fatty acid anilides and acylated phenyl amino propanediol derivatives or PAPs) were found to be good chemical markers of toxic oils. In this work, a new method has been developed to analyze these aniline derivatives in oil samples by HPLC-MS and HPLC-MS/ MS with an API source. For their quantification, three different internal standards were used, one for anilides and two for PAPs. Quantification limits were 8 ppm for anilides and 0.2 ppm for PAPs. Anilides and PAPs were found in marker-positive samples at levels up to 50 000 and 330 ppm, respectively. The relative abundance of the different fatty acid anilides and PAPs correlates with the fatty acid composition of the oils. More than 2600 different samples were analyzed by this method in the most exhaustive screening of suspected toxic oils carried out to date.

Previous studies have demonstrated that intestinal preconditioning protects the organ from ischemia reperfusion damage. Xanthine oxidase mediating free radical generation contributes to the development of injury associated to ischemia reperfusion. Thus, any process able to modulate the oxygen free radical generation system could attenuate the injury. Also, it is known that nitric oxide is implicated in the preconditioning response. The aim of this work is to determine: (1) the effect of intestinal preconditioning on the xanthine oxidase system, (2) the relevance of this system in the development of injury, and (3) its relationship with nitric oxide. For this purpose, we have determined the activity of the xanthine dehydrogenase/xanthine oxidase system, the levels of its substrate (xanthine), and end-product (uric acid) and oxidant stress status in rat small intestine subjected to ischemic pre-conditioning. The effects of nitric oxide inhibition have also been evaluated. Results show that the percentage of xanthine dehydrogenase to xanthine oxidase conversion, xanthine, uric acid concentration, lipoperoxides, and reduced glutathione were significantly reduced in preconditioned rats irrespectively of nitric oxide inhibition. In summary, this work shows that oxidative stress in intestinal preconditioning is reduced as consequence of the diminished conversion of xanthine dehydrogenase to xanthine oxidase, and also as a consequence of the reduced availability of xanthine.

This work studied the activation of hepatic macrophages during acute pancreatitis and the involvement of these cells in the lung inflammatory response. Pancreatitis was induced in Wistar rats by intraductal administration of 5% sodium taurocholate. Three hours after pancreatitis induction, the degree of pulmonary inflammation, TNF-alpha levels, and P-selectin expression were evaluated. The generation of TNF-alpha by Kupffer cells was also measured. Pancreatitis increases the serum concentration of TNF-alpha, neutrophil infiltration, and P-selectin expression in pancreas and lung. In addition, Kupffer cells generate increased levels of TNF-alpha. When Kupffer cells were inhibited, the increase in serum TNF-alpha levels and the infiltration of neutrophils in the lung were prevented, but P-selectin expression remained unmodified. We conclude that pulmonary inflammation induced by acute pancreatitis is mediated by Kupffer cell activation and that pancreatitis induces the expression of P-selectin on pulmonary endothelial cells but this effect is not mediated by Kupffer cells.

The design of more effective therapies for metastatic disease involves development of new compounds able to specifically block the malignant process. We demonstrated previously that a new synthetic nitrogenated compound 3'-1-chloroethyl-2,3-dihydro-1H-imidazo-(2, 1-i)-purine-4-ium-7-yl-3'-deoxy-1',5', 6'-tri-O-(methylsulfonyl)-muco-inositol chloride (DIC) had an anti-proliferative activity on tumor cells in vitro. In the present work we demonstrate that DIC induces apoptosis on the LM3 murine mammary adenocarcinoma cell line in vitro and has anti-angiogenic activity in vivo. We also evaluated toxicity, biodistribution and anti-neoplastic properties of DIC in vivo. Toxicity studies allowed us to establish the LD50 (750 mg/kg body weight). Administration of 250 mg/kg/day (LD10) for 6 days did not cause overt toxic effects. Biodistribution assays revealed that DIC was rapidly eliminated (60% at t=10 min), although it accumulated in tumor tissue at higher concentrations than in other tissues. Daily s.c. treatment with DIC (LD10) for 24 days significantly reduced the number of spontaneous lung metastases. These results suggest that DIC has the ability of impairing the metastatic development by inhibiting angiogenesis and inducing apoptosis on tumor cells.

Formation of nitric oxide (NO) in ischemia-reperfusion (I-R) associated with pancreas transplantation could modulate the inflammatory response. In this sense, previous studies have demonstrated the action of NO on vasoactive substances like prostacyclin or endothelin. The present study was designed to evaluate the contribution of endothelin to the inflammatory events induced by NO in the I-R process associated with pancreas transplantation. For this purpose, pancreatic levels of endothelin, neutrophil infiltration, and prostacyclin were evaluated in an experimental model of pancreas transplantation after inhibition of NO synthesis or after NO inhibition plus addition of endothelin. Results show significant posttransplantation increases in endothelin, neutrophil infiltration, and prostacyclin production. These increases were prevented by NO inhibition. Endothelin administration plus nitric oxide inhibition reversed this effect, resulting in an increase in myeloperoxidase and 6-keto-prostaglandin F1alpha. These results suggest that the proinflammatory effects of NO in I-R associated with pancreas transplantation are mediated by the induction of endothelin generation.

The role of nitric oxide, produced during reperfusion as a function of preservation time, in the development of the inflammatory process in pancreas transplantation has been explored. For this purpose, the effect of nitric oxide synthase inhibition, as well as 6-keto-prostaglandin F1alpha, leukotriene B4, and lipoperoxidation levels were evaluated in an experimental model of rat pancreas transplantation after different periods of cold preservation. The results show posttransplantation increases in 6-keto-prostaglandin F1alpha, leukotriene B4, and lipoperoxidation levels in pancreatic tissue and in plasma lipase. When ischemia was induced for 30 min, nitric oxide synthase inhibition prevented these increases, and L-arginine was able to reverse this effect. By contrast, nitric oxide synthase inhibition has no effect when ischemia was prolonged for 12 hr. In summary, this study suggests that, during reperfusion, nitric oxide modulates 6-keto-prostaglandin F1alpha synthesis, lipoperoxidation levels, and the development of pancreatic injury but only when the ischemic period is quite short.

The reaction of 16 alpha,17 alpha-epoxy-3 beta-hydroxy-5-pregnen-20-one with 6-methyl thiopurine activated with sodium hydride leads to the coupling of the purine base with the carbonyl group at C-20 to give a steroidal nucleoside analog, which is termed "nucleosteroid." In the presence of an excess of purine, a parallel reaction occurs in which the oxirane ring is opened, presumably by nucleophilic attack of an intermediate C-20 oxyanion, and yields as the main product of reaction an oligomeric mixture of nucleosteroid units linked together by ether linkages. Analogous reactions conducted with 3 beta-hydroxy-5-pregnen-20-one and with 3 beta,17 alpha-dihydroxy-5-pregnen-20-one gave minor amounts or only traces of the corresponding coupling adduct, and oligomerization did not occur. This behavior is interpreted in terms of the conformational differences showed by the different steroids to the attack by the purine.

Within the framework of an European Commission-funded project, groups of industrial workers exposed to heavy metals (cadmium, mercury and lead) or solvents were studied together with corresponding control groups. Eighty-one measurements were carried out on urine and serum samples and the scientific results together with individual questionnaire information were entered into a central database. Data obtained was assessed centrally and individually in subsidiary studies. The measurable contributions were assessed either singly or in combination, of smoking, gender, metal exposure and site, to nephrotoxicity. The potential value of each test as an indicator of nephrotoxicity was then assessed on the basis of sensitivity and specificity. A number of new tests including prostaglandins and for extracellular matrix components were investigated as well as established tests for renal damage and dysfunction. The data obtained from this comprehensive study emphasises the value of noninvasive biomarkers for the early detection of nephrotoxicity due to environmental toxins. The urinary profile varied with the type of environmental/occupational toxin. By careful selection of a small panel of markers they can be used to indicate the presence of renal damage, the principal region affected, and to monitor the progress of disease and damage. Biomarkers were also used to confirm and tentatively establish safe exposure levels to nephrotoxins.

With established urinary markers of kidney integrity the early renal effects of lead have previously been considered to be mainly tubular or tubulointerstitial. In a cross-sectional study on 81 male lead-exposed workers and 45 age-matched controls (median blood lead concentrations 2.03 and 0.34 mumol/l respectively) not only well-established but also new urinary markers of renal integrity preferentially or exclusively located along the different nephron segments were analysed. Markers related to the glomerulus were 6-keto-prostaglandin 1 alpha, thromboxane B2, mainly produced in the glomerulus, and the extracellular matrix protein fibronectin. Markers of the proximal tubule were the brush-border antigens BBA, BB50, and HF5 and the intestinal alkaline phosphatase. Prostaglandin E2 and F2 alpha, preferentially synthesized in the collecting duct and medullary interstitial cells, served as markers of these more distal nephron segments. In contrast to previous studies on the early phase of lead nephrotoxicity, not only tubular but also glomerular involvement could be shown in the study presented here by increases in the median values of 6-keto-prostaglandin 1 alpha and decreases in fibronectin. The proximal tubular markers intestinal alkaline phosphatase and BBA confirmed that this particular segment of the nephron is affected by lead. Effects on the collecting tubule or medullary interstitial cells could also be observed. It is concluded that lead affects both the glomerulus and the tubular apparatus and that combinations of new and established markers could be valuable for a better definition and early detection of lead nephropathy.

Starting from a mesylated inosamine several ethanol-, β - chloroethyl-, β-mesyloxy ethyl-, and β-iodoethylamino compounds were synthesized. Different chlorinated derivatives were obtained through variations in the chlorinating reagent, solvent, and reaction time.

2084 Background: Response to alkylating chemotherapy in patients with high grade gliomas (HGG) has been found correlated to epigenetic silencing of the DNA repair gene MGMT (O6-methylguanine-DNA methyltransferase) in the tumor tissue. Patients with HGG expressing a methylated MGMT promoter benefited from alkylating chemotherapy in terms of a prolonged survival as compared to patients with unmethylated MGMT promoter. Methods: Our study cohort comprised 47 patients with HGG, all treated with concomitant chemotherapy and radiotherapy in our institution. 23/47 patients (8 women, 15 men, aged 22.4–64.5 years, median 36.3) survived longer than 36 months (range of survival times 36–137 months, in median 46.9 months) and were defined as long term survivors (LS). 24/47 patients (5 women and 19 men, aged 18.3–73.3 years, median 47.7) with early tumor relapse who survived in median for 23.5 months were defined as HGG patients with conventional survival (CS). In all cases, we extracted DNA from formalin-fixed and paraffin-embedded tumor tissue samples. The methylation status of the MGMT promoter was determined by bisulfide modification of the DNA and methylation-specific polymerase-chain- reaction (MSP). MSP results were rated by 4 independent observers. Results: There was high interobserver agreement at interpretation of MSP results (range of kappa values: 0.71–0.87). Among LS, we found MGMT promoter methylation in 13/24 (81.5%) patients and an unmethylated MGMT promoter in 3 patients, whereas the MSP results were not interpretable in 7 patients of this patient subgroup. Among CS, we found promoter methylation in 16 patients (66.6%), unmethylated promoter in 6 patients and uninterpretable results in one patient. There was no statistically significant difference in MGMT promoter methylation rate between LS and CS. Conclusions: The proportion of gliomas with methylated MGMT promoter in this series is unexpectedly high, particularly for CS patients. Potential explanations for this finding are methodological differences due to the use of paraffin-embedded tumors instead of frozen tumor material as in most published series and a potential random accumulation of MGMT positive tumors in the patients with CS survival. No significant financial relationships to disclose.

Experiments were performed in which meteoritic iron, iron ore and nickel-iron alloy were used to catalyze (in Fischer-Tropsch synthesis) the reaction of deuterium and carbon monoxide in a closed vessel. Normal alkanes and alkenes and their monomethyl substituted isomers and aromatic hydrocarbons were synthesized. Iron oxide and oxidized-reduced Canyon Diablo used as Fischer-Tropsch catalysts were found to produce aromatic hydrocarbons in distributions having many of the features of those observed in carbonaceous chondrites, but only at temperatures and reaction times well above 300 C and 6-8 h.

The reaction of octa-O-acetylcellobiononitrile with sodium methoxide, and acetylation of the resulting mixture, afforded the anomeric peracetates of O-β- D -glucopyranosyl-(1→3)- D -arabinopyranose and O-β- D -glucopyranosyl-(1→3)- D -arabinofuranose, which were isolated by fractional recrystallization. Their structures, anomeric configurations, and conformations were studied by chemical, optical, and spectroscopic methods.

Penta-O-acetyl and penta-O-propanoyl derivatives of 1,1-bis(benzamido)-1-deoxy- d -glucitol are transformed into 1-acetamido-1-benzamido-1-deoxy- d -glucitol and 1-benzamido-1-deoxy-1-propanamido- d -glucitol, respectively, by heating with a suspension of potassium cyanide in acetonitrile, and subsequently O-deacylating with sodium methoxide in methanol. The reaction was also studied in the presence of a crown ether. When other nucleophiles (HO− and CH3O−) or other aprotic solvents (propanonitrile, benzene) were employed, the yields of transacylation products diminished noticeably; likewise, the use of sodium as the counter-ion significantly affected this reaction. These results are qualitatively discussed in terms of the solvent effects on the reactivity of the nucleophiles employed.

The reaction of N -acetyl-α- d -glucofuranosylamine with 2,2-dimethoxypropane, catalyzed by p -toluenesulfonic acid, gave 1-acetamido-2,3:5,6-di- O -isopropylidene-1- O -methyl- d -glucitol (65.6%), 1-acetamido-2,3- O -isopropylidene-1- O -methyl- d -glucitol (3.7%), and N -acetyl-5,6- O -isopropylidene-α- d -glucofuranosylamine (3.2% yield). The structures of these compounds were determined by chemical and spectroscopic methods, and their relation to the pattern of n.m.r. resonances of the isopropylidene methyl groups is discussed.

The mass spectrometric structural identification of a new thromboxane (TXB2) derivative is reported. The derivative is formed by sequential oximation at C-11 with boronation of the 9,12-hydroxylated positions in addition to the usual methyl ester and 15-silylether formation. The practical advantages of this new multifunctional derivative lie in the simple fragmentation pattern with a relatively high mass (m/z 407) base peak at M-144, very suitable for selected ion monitoring. The determination of fragmentation pathways of significant ions rests on the comparative study of mass spectra of MO(NBB)TMS, d3-MO(NBB)TMS and PFBO(NBB)TMS 1 methyl ester derivatives.

The reaction of aqueous ammonia with octa- O -acetylgentiobiose gives 1,1-bis-(acetamido)-1-deoxy-6- O -β- D -glucopyranosyl- D -glucitol ( 1 ) and N -acetyl-6- O -β- D -glucopyranosyl-β- D -glucofuranosylamine ( 3 ). The structure of the furanoid compound 3 was demonstrated by methylation and hydrolysis techniques, and its anomeric configuration through periodate oxidation and borohydride reduction.

Benzoylation of L -sorbose at room temperature with an excess of benzoyl chloride in pyridine gave a mixture of unsaturated cyclic and acyclic benzoates. The synthesis, and the structure of the title compound based on spectroscopic and ozonolysis studies, are reported. Ethyl 2,3,4,5-tetra- O -benzoyl- L -xylonate is also described, as well as the mass spectra of these acyclic benzoates.