MITO END-3: Efficacy of Avelumab immunotherapy according to molecular profiling in first-line endometrial cancer therapy

BACKGROUND

Immunotherapy combined with chemotherapy significantly improves progression-free survival compared to first-line chemotherapy alone in advanced endometrial cancer, with a much larger effect size in microsatellite-instability high (MSI-H) cases. New biomarkers might help to select patients that may have benefit among those with a microsatellite-stable (MSS) tumor.

METHODS

In a pre-planned translational analysis of the MITO END-3 trial, we assessed the significance of genomic abnormalities in patients randomized to standard carboplatin/paclitaxel without or with avelumab.

RESULTS

Out of 125 randomized patients, 109 had samples eligible for next-generation sequencing (NGS) analysis, and 102 had MSI tested. According to The Cancer Genome Atlas (TCGA), there were 29 cases MSI-H, 26 MSS TP53 wild-type (wt), 47 MSS TP53 mutated (mut), and one case with POLE mutation. Four mutated genes were present in more than 30% of cases: TP53, PIK3CA, ARID1A, and PTEN. Eleven patients (10%) had a BRCA1/2 mutation (five in MSI-H and six in MSS). High TMB (≥10 Muts/Mb) was observed in all MSI-H patients, in four out of 47 MSS/TP53 mut, and no case in the MSS/TP53 wt category. The effect of avelumab on progression-free survival significantly varied according to TCGA categories, being favorable in MSI-H and worst in MSS/TP53 mut (P interaction=0.003); a similar non-significant trend was seen in survival analysis. ARID1A and PTEN also showed a statistically significant interaction with treatment effect, which was better in the presence of the mutation (ARID1A P interaction=0.01; PTEN P interaction=0.002).

CONCLUSION

The MITO END-3 trial results suggest that TP53 mutation is associated with a poor effect of avelumab, while mutations of PTEN and ARID1A are related to a positive effect of the drug in patients with advanced endometrial cancer.

Effect of pomegranate (Punica granatum) anthelmintic treatment on milk production in dairy sheep naturally infected with gastrointestinal nematodes

Anthelmintic drug resistance has proliferated across Europe in sheep gastrointestinal nematodes (GINs). Sheep welfare and health are adversely impacted by these phenomena, which also have an impact on productivity. Finding alternatives for controlling GINs in sheep is thus of utmost importance. In this study, the anthelmintic effectiveness (AE) of a Calabrian ethnoveterinary aqueous macerate based on Punica granatum (whole fruits) was assessed in Comisana pregnant sheep. Furthermore, an examination, both qualitative and quantitative, was conducted on milk. Forty-five sheep were selected for the investigation. The sheep were divided by age, weight, physiological state (pluripara at 20 days before parturition), and eggs per gram of feces (EPG) into three homogeneous groups of 15 animals each: PG received a single oral dosage of P. granatum macerate at a rate of 50 mL per sheep; AG, treated with albendazole, was administered orally at 3.75 mg/kg/bw; and CG received no treatment. Timelines were as follows: D0, treatments, group assignment, fecal sampling, and AE assessment; D7, D14, D21, fecal sampling, and AE evaluation. The FLOTAC technique was used to evaluate the individual GIN fecal egg count (FEC) using a sodium chloride flotation solution (specific gravity = 1.20) and 100 × (1-[T2/C2]) as the formula for evaluating FEC reduction. Following the lambs' weaning, milk was collected on the following days (DL) in order to quantify production: DL35, DL42, DL49, DL56, DL63, DL70, DL77, and DL84. The amount of milk produced by every animal was measured and reported in milliliters (ml) for quantitative evaluations. Using MilkoScan TM fT + foss electric, Denmark, the quality of the milk (casein, lactose, protein concentration, and fat, expressed as a percentage) was assessed. The macerate demonstrated a considerable AE (51.8%). Moreover, its use has resulted in higher milk production rates quantitatively (15.5%) and qualitatively (5.12% protein, 4.12% casein, 4.21% lactose, and 8.18% fat). The study showed that green veterinary pharmacology could be the easiest future approach to counteracting anthelmintic resistance in sheep husbandry.

Alternative academic approaches for testing homologous recombination deficiency in ovarian cancer in the MITO16A/MaNGO-OV2 trial

Background

The detection of homologous recombination deficiency (HRD) can identify patients who are more responsive to platinum and poly ADP ribose polymerase inhibitors (PARPi). MyChoice CDx (Myriad) is the most used HRD test in ovarian cancer (OC). However, some limitations of commercial tests exist, because of the high rate of inconclusive results, costs, and the impossibility of evaluating functional resistance mechanisms.

Patients and methods

Two academic genomic tests and a functional assay, the RAD51 foci, were evaluated to detect HRD. One hundred patients with high-grade OC enrolled in the MITO16A/MaNGO-OV2 trial and treated with first-line therapy with carboplatin, paclitaxel, and bevacizumab were analyzed.

Results

The failure rate of the two genomic assays was 2%. The sensitivity in detecting HRD when compared with Myriad was 98.1% and 90.6%, respectively. The agreement rate with Myriad was 0.92 and 0.87, with a Cohen’s κ coefficient corresponding to 0.84 and 0.74, respectively. For the RAD51 foci assay, the failure rate was 30%. When the test was successful, discordant results for deficient and proficient tumors were observed, and additional HRD patients were identified compared to Myriad; sensitivity was 82.9%, agreement rate was 0.65, and Cohen’s κ coefficient was 0.18. The HRD detected by genomic assays and residual tumor at primary surgery and stage was correlated with progression-free survival at multivariate analysis.

Conclusions

Results suggest the feasibility of academic tests for assessing HRD status that show robust concordance with Myriad and correlation with clinical outcome. The contribution of the functional information related to the RAD51 foci test to the genomic data needs further investigation.

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Deficiency in homologous recombination repair of DNA generates genomic instability and permanent genomic changes.

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HRD status is fundamental for identifying OC patients suitable for platinum and PARPi treatment.

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HRD testing is considered a topic with urgent need for improvement, going beyond those available commercially.

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Within this study, two academic genomic tests and a functional assay, the RAD51 foci, were evaluated to detect HRD.

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Our tests compare favorably with the reference Myriad assay and correlate with the outcome of high-grade OC patients.

P49 SURGICAL OPEN AORTA TRANSCATHETER VALVE IN VALVE IMPLANT FOR A MALFUNCTIONING AORTIC BIOPROSTHESIS

Background

Most cases of aortic valve bioprosthesis degenerative disease are currently best managed by transcatheter aortic valve replacement (TAVR). Compared to redo surgery, advantages of TAVR include reduced invasiveness and a minimized prosthesis gradient; however, this approach is occasionally unfeasible due to the risk for coronary flow impairment or prosthesis stent dimensions unfit to accommodate an appropriately sized device. We present a case of an open TAVR after surgical leaflets excision of a failing aortic valve bioprosthesis.

Case Summary

A 76 years old female with type 2 diabetes, hypertension and dyslipidemia was referred to our institution for a malfunctioning 21 Carpentier Edwards pericardial aortic valve bioprosthesis implanted 9 years earlier. Patient was initially considered for a valve in valve TAVR. However, because of very low–lying coronary arteries origin at preoperative CT scan we estimated substantial chances for ostia impingement when prosthesis leaflets would have been stretched out by the deploying transcatheter device (Figure 1); although feasible, conventional redo surgery with bioprosthesis excision and re–suture was not preferred because of patients age and comorbidities; risk of damaging the aortic ring and wall including coronaries emergence when dissecting out the stent of the biopsosthesis and reimplanting a new one was also evaluated. We therefore opted for an hybrid procedure. After redo median sternotomy, careful dissection of adhesions, central Cardio–Pulmonary Bypass (CPB), aortic cross clamp and antegrade cardioplegia, a transverse aortotomy was done. The prosthesis was inspected and found grossly deteriorated: leaflets only were excised leaving the stent intact (Figure 2) and a 23 Sapien3 Ultra valve was carefully deployed under direct vision. Coronary ostia were checked and found patent. Myocardial ischemia and CPB times were 61 and 85 minutes respectively. Intensive care unit stay was 2 days. After a reassuring postoperative CT scan (Figure 3), patient was discharged home 11 days after surgery.

Conclusions

We found this approach a good compromise when dealing with challenging aortic valve reoperations, as it is associated to reduced surgical complexity and potential for less morbidity and mortality compared to conventional surgery when low coronary ostia make valve in valve TAVR unachievable.

Age-related metabolic changes of pre-weaned Simmental calves fed whole bulk milk and ad libitum calf starter

The present study aimed to investigate blood biomarkers encompassing the metabolic status of Simmental calves, with emphasis on weekly differences in the pre-weaning period. Ten Italian Simmental calves were used for the experiment and were offered 6 L of bulk whole milk/d from an open-bucket starting at day 2 from birth and through 5 weeks. Blood samples were collected at birth and weekly to assess biochemical indicators related to energy metabolism and liver function, minerals, markers of inflammation, and oxidative stress. Body weight (BW), heart girth (HG), and solid feed intake were positively affected by aging. Calves increased solid feed intake consumption after 2 week and reached a BW gain of 28.16 kg at 5 weeks. Most of blood biomarkers were affected by age, mostly concerned the period after birth and day 1, whereas no changes were observed for haptoglobin, urea, β-hydroxybutyrate, Na, and K. The amount of milk fed to calves throughout this study contributes to the maintenance of glucose concentration over time, coupled also with a considerable amount of starter intake. Glucose levels associated to the high ADG (0.89 ± 0.09 kg/d, mean ± SEM) suggest that calves experienced a positive energy balance throughout the entire pre-weaning period. Similar levels of haptoglobin and ceruloplasmin, together with a gradual increase of albumin, reflect good liver functionality and a stable condition regarding the inflammatory status. These results suggest that blood biomarkers of Simmental calves in the pre-weaning phase vary with growing stages.

Increased early inflammatory response and osteoclastic activity in gingival tissues following conventional osseous resective surgery compared with the fibre retention technique: a pilot study

BACKGROUND AND OBJECTIVE

The retention of suprabony connective fibres attached into the root cementum during fibre retention osseous resective surgery (FibReORS) results in a more conservative intrasurgical removal of bone, and limits further bone loss and patient morbidity during healing, compared with conventional osseous resective surgery (ORS). This may be a result of the protective effect of preserved connective tissue over the interproximal sites and the lower activation of the inflammatory mechanisms. Thus, the aim of this pilot study was to compare the expression of inflammatory and osteoclastic activity markers in gingival tissues following FibReORS and ORS in the early postsurgical phase.

MATERIAL AND METHODS

Twenty-six posterior sextants requiring osseous resective surgery were selected in 13 patients with chronic periodontitis: 13 sextants were randomly assigned to ORS and 13 to FibReORS in a split-mouth design. Gingival biospies were collected during the surgical sessions and at suture removal. Tissue samples were analysed to evaluate the expression of proinflammatory and immunity regulatory mediators (interleukin-1α, C-X-C motif chemokine ligand 5, interferon-γ and tumour necrosis factor-α), cluster of differentiation 14 (CD14; a monocyte/macrophage marker) and TRAP (an osteoclast marker) using immunohistochemical, immunofluorescence and cytofluorimetric analyses, respectively.

RESULTS

Postsurgery, a higher number of inflammatory cells and stronger expression of proinflammatory cytokines were observed in the epithelium and connective tissue of ORS gingival samples compared with FibReORS gingival samples (p < 0.001). This was accompanied by increased numbers of CD14-positive and TRAP-positive cells.

CONCLUSION

Retention of the supracrestal connective fibres appears to reduce the postsurgical intensity of the host-mediated inflammatory response.

Spectrum of enteropathogens detected by the FilmArray GI Panel in a multicentre study of community-acquired gastroenteritis

The European, multicentre, quarterly point-prevalence study of community-acquired diarrhoea (EUCODI) analysed stool samples received at ten participating clinical microbiology laboratories (Austria, Finland, France, Germany, Greece, Ireland, Italy, Portugal, Romania, and the UK) in 2014. On four specified days, each local laboratory submitted samples from ≤20 consecutive patients to the Austrian Study Centre for further testing with the FilmArray GI Panel (BioFire Diagnostics, Salt Lake City, UT, USA). Of the 709 samples from as many patients received, 325 (45.8%) tested negative, 268 (37.8%) yielded only one organism, and 116 (16.4%) yielded multiple organisms. Positivity rates ranged from 41% (30 of 73 samples) in France to 74% (59 of 80 samples) in Romania. With the exception of Entamoeba histolytica and Vibrio cholerae, all of the 22 targeted pathogens were detected at least once. Enteropathogenic Escherichia coli, Campylobacter species, toxigenic Clostridium difficile, enteroaggregative E. coli, norovirus and enterotoxigenic E. coli were the six most commonly detected pathogens. When tested according to local protocols, seven of 128 positive samples (5.5%) yielded multiple organisms. Overall, the FilmArray GI Panel detected at least one organism in 54.2% (384/709) of the samples, as compared with 18.1% (128/709) when testing was performed with conventional techniques locally. This underlines the considerable potential of multiplex PCR to improve routine stool diagnostics in community-acquired diarrhoea. Classic culture methods directed at the isolation of specific pathogens are increasingly becoming second-line tools, being deployed when rapid molecular tests give positive results. This optimizes the yield from stool examinations and dramatically improves the timeliness of diagnosis.

Review of cerebellopontine angle medulloblastoma

Cerebellopontine angle (CPA) medulloblastomas (MB) are rare lesions with few cases previously described in the literature. We report two further cases of CPA MB. The patients were a 22-year-old man and a 26-year-old woman with a mass developing in the CPA. The preoperative radiological diagnosis was vestibular schwannoma in the first case and petrosal meningioma in the second case. The patients were operated on through a retrosigmoid approach. The intraoperative findings revealed an intra-axial tumour and the histological diagnosis was classic type of MB in both cases. We review the literature and discuss pathological and radiological features and possible pathogenesis of CPA MB, underlining the necessity to consider MB in the differential diagnosis of CPA lesions.

Extra-anatomical hepatic artery reconstruction following post-embolization iatrogenic dissection and arterial anastomotic rupture in two liver transplant recipients

When hepatic artery reconstruction is required during hepatic transplantation, this is generally performed with donor vessels. We describe two cases requiring a prosthesis. The first case was a 58-year-old man transplanted for cirrhosis complicated by hepatocellular carcinoma. During transplantation, dissection of the celiac trunk occurred due to arterial embolization and the use of the patient's vessels was impossible. An extra-anatomical bypass between the infra-renal aorta and the donor hepatic artery was performed via the interposition of a graft tube. The second case was a 52-year-old man transplanted for cirrhosis complicated by hepatocellular carcinoma. On day 16, a ruptured anastomosis was suspected and the patient underwent emergency revision laparotomy. Arterial revascularisation was performed with an aortohepatic bypass using a synthetic GoreTex((R)) graft. Patient follow-up was uneventful.

Adenylate cyclase/cAMP pathway downmodulation counteracts apoptosis induced by IFN-alpha in human epidermoid cancer cells

We have reported previously that interferon-alpha (IFN-alpha) induces apoptosis that is counteracted by an epidermal growth factor (EGF) --> Ras --> extracellular signal-regulated kinase (ERK)-dependent survival response in human epidermoid cancer KB cells. We have studied the effects of the cytokine on the cAMP-dependent pathway in these cells. A decrease in the intracellular cAMP levels was recorded in KB cells treated with IFN-alpha, whereas forskolin induced an increase in the production of cAMP that was reduced in the presence of IFN-alpha, suggesting a reduction in the activity of adenylate cyclase (AC) induced by IFN-alpha. These effects were paralleled by significant change in the expression of some AC catalytic subunit(s) and by reduction in the activity of protein kinase A (PKA). 8-Br-cAMP completely antagonized the reduction of PKA activity induced by IFN-alpha, whereas PKA inhibitor KT5720 enhanced the reduction of the enzyme activity induced by IFN-alpha. We have found that IFN-alpha induced a decrease in cAMP response element binding protein (CREB) phosphorylation without changes in its total expression. The concomitant treatment with IFN-alpha and 8-Br-cAMP potentiated and KT5720 counteracted apoptosis induced by IFN-alpha alone. In conclusion, these data suggest that the decrease in AC/cAMP pathway activity is a survival response to the apoptosis induced by IFN-alpha. Therefore, this pathway could represent a target to enhance the antitumor activity of IFN-alpha.

Differentiation of H9c2 cardiomyoblasts: The role of adenylate cyclase system

The adenylate cyclase (AC)/cAMP/cAMP-dependent protein kinase pathway controls many biological phenomena. The molecular mechanisms by which cAMP induces alternative commitment towards differentiation or proliferation are not still completely known. The differentiation of myoblast cell lines into myocytes/myotubes represents a well-established model of skeletal muscle differentiation. We analyzed the AC/cAMP pathway during terminal differentiation of H9c2 myoblasts. When cultured in low-serum containing medium, H9c2 myoblasts exit the cell cycle and differentiate into myocytes/myotubes. A key step of this process is the expression of myogenin, an essential transcription factor for the terminal differentiation into myocytes. During this phenomenon we observed a decrease in both cAMP levels and AC activity, which suggests a functional negative role of cAMP on the differentiation process of H9c2 cells. 8-Br-cAMP and other cAMP-elevating agents, such as forskolin, IBMX, and isoproterenol, negatively affected skeletal muscle differentiation of H9c2 myoblasts. Both AC activity down-regulation and intracellular cAMP reduction were accompanied by significant variations in the levels of membrane proteins belonging to the AC system (AC catalytic subunit, G(alphai-1), G(alphas)). The functional relationship between intracellular cAMP content and protein levels of AC system is discussed.

Treatment of v-Ki-ras-transformed SVC1 cells with low retinoic acid induces malignancy reversion associated with ras p21 down-regulation

The effect of nontoxic, low concentrations (10(-8) M) of retinoic acid (RA) for a relatively long time (28 days) on a Kirsten ras-virus transformed cell line (Ki-SVC1), derived from the rat seminal vesicle epithelium, was investigated. In these experimental conditions, the cell treatment with RA induced a decrease of the proliferation rate, apoptosis and a marked reduction of both anchorage-independent growth and tumorigenicity. These biological responses were either preceded or associated with important changes in adenylate cyclase/protein kinase C signaling pathways, the activation of important apoptosis-linked genes and a marked decrease of the v-Ki-ras p21 protein. The significance of these findings is discussed.

tTGase/G alpha h protein expression inhibits adenylate cyclase activity in Balb-C 3T3 fibroblasts membranes

Stably transfected Balb-C 3T3 fibroblasts (clone 5), overexpressing a catalytically active tissue transglutaminase, showed a basal adenylate cyclase activity lower than control cells (clone 1). Several modulators of the adenylate cyclase activity (forskolin, Mn2+ and pertussis toxin) showed the existence of a marked negative control on the adenylate cyclase activity present in clone 5 cells. Very interestingly, this same marked negative control was also found in a Balb-C 3T3 fibroblast clone stably transfected with a mutagenized human tissue transglutaminase (mut277 cys > ser) virtually devoid of transglutaminase catalytic activity (clone Ser). Conversely, a significant increase of the adenylate cyclase activity was observed in bovine aortic endothelial cells after the lowering of tissue transglutaminase expression levels by the transfection of an eukaryotic expression vector containing the gene for tissue transglutaminase in antisense orientation. All these findings suggest a possible role for type II tissue transglutaminase as a negative modulator of the adenylate cyclase activity in different cell types, beside its transglutaminase enzyme activity.

Clinical features and hormonal characteristics in a case of ovarian arrhenoblastoma

We report a case of a 34-year-old woman affected with ovarian arrhenoblastoma characterized by very high testosterone (T) levels (34.0-60.0 ng/ml; n.v.0.2-0.9) and suppressed gonadotropin levels. The physical examination revealed: severe hirsutism, acne, amenorrhea and other virilization signs. Basal hormonal evaluation also showed a markedly elevated 17-hydroxyprogesterone (17-OHP) and a mild delta 4 Androstenedione (A) and dehydroepiandrosterone sulfate (DHEAs) increase. ACTH test induced only slight changes in androgen secretion. By contrast, dexamethasone test greatly decreased A and DHEAs whereas T levels were only partially suppressed. Moreover, hCG test was clearly stimulatory for T and A. Suppressed gonadotropin levels did not respond to LHRH stimulation. The removal of the neoplasia was followed by normalization of T levels and increase of serum gonadotropins with subsequent restoration of a normal responsiveness to LHRH and resumption of an ovulatory menstrual cycle. This observation suggests that the high T levels played a primary role in the pathogenesis of the gonadotropin suppression and anovulation. Recovery of acne was complete whereas hirsutism score was reduced but still elevated after one year. This may be due to postoperative A and DHEAs levels slightly above the normal range, indicating the presence of adrenal hyperandrogenism.

Correlations between abnormalities on brain SPECT scan and interictal EEG-foci in children with 'intractable' partial epilepsy

SPECT scanning with Tc99mHM-PAO was performed on 40 children with 'intractable' partial epilepsy; 27 patients had abnormalities on SPECT images consisting of areas of decreased cerebral blood flow. In 18 of these 27 subjects there was a good correlation between site of the abnormalities on SPECT scan and interictal EEG foci. 12 patients with regionally decreased CBF had also neuroimaging (C.T. and/or R.M.I.) abnormalities. The brain SPECT provides more precise detection of epileptogenic foci, when used to complement EEG, also in childhood-onset epilepsy.

Aryl sulfotransferase-IV-catalyzed sulfation of aryl oximes: steric and substituent effects

The aryl sulfotransferases (EC 2.8.2.1) catalyze the sulfation of a wide variety of hydroxyl-containing molecules. The enzyme reaction requires 3'-phosphoadenosine-5'-phosphosulfate as the sulfate donor and several isozymes with broad, overlapping substrate specificities have been identified. One of the isozymes in rat hepatic cytosol, isozyme IV, is a major contributor to enzymatic sulfation. It exhibits the broadest substrate specificity of the three isozymes which have been characterized to date. Its substrates include a wide variety of phenols, certain aromatic hydroxylamines and benzylic alcohols. The latter two substrate types have implicated this isozyme in the bioactivation of several toxic compounds. Relatively little information is available, however, on substrate molecular features which account for the ability of isozyme IV to sulfate compounds not utilized by isozymes I and II. A recent investigation of isozymes I and II with a series of model aryl-oxime substrates suggested that catalysis is influenced primarily by steric factors and in particular substrate planarity and hydroxyl group orientation (Mangold et al. (1989) Biochim. Biophys. Acta 991, 453-458). In the present study, isozyme IV was investigated to characterize its substrate requirements with a more extensive series of aryl oxime substrates. The results indicated that isozyme IV has a much less stringent requirement for planarity and hydroxyl-group orientation than isozymes I or II. Isozyme IV accepted a greater variety of aryl-oxime substrates, including several classes which were not substrates for isozymes I and II. A comparison of kinetic constants and catalytic efficiencies suggested that substituent effects play a role in the sulfation of aryl oximes by isozyme IV.

Essential mental anorexia. Psychopathologic considerations and analysis of a case

The AA. report the case of an anorexic girl, who could resume her evolutive process after an individual psychotherapy and parent's psychotherapy. In this way she could work out her defensive mechanisms and her EGO could internalize a previous menacing and persecutory maternal object.

Brain SPECT and migraine in childhood

The recent development of SPECT has introduced a new procedure to evaluate neurological diseases. By mean of Tc99mHM-PAO we studied a group of 19 pediatric subjects (7 males and 12 females) with different form of migraine, within five days after the last headache attack. Postictally SPECT shows regionally decreased CBF in 3/4 of HM, in 5/6 of BAM, in 5/5 of CM and in 2/4 of M.

Treatment of "intractable childhood epilepsy" with high doses of intravenous gamma-globulins

The authors refer their experience in the treatment of intractable childhood epilepsies (18 cases) with intravenous gamma globulin. Seven patients showed great reduction or indeed disappearance of the seizures whereas modest improvement was observed in other 4 cases. A better organization of the EEG corresponded to this clinical improvement with a reduction or disappearance of paroxysmal anomalies, and also a better result in motor and cognitive capacities.

Sulfation of mono- and diaryl oximes by aryl sulfotransferase isozymes

Aryl sulfotransferases (3'-phosphoadenylsulfate:phenol sulfotransferase, EC 2.8.2.1) catalyze the sulfonation of a wide variety of hydroxyl-containing substrates, including numerous xenobiotics. The chemical diversity of aryl sulfotransferase substrates is in part attributable to the presence of multiple isozymes, each of which has broad substrate specificity. Of the aryl sulfotransferase isozymes in rat liver cytosol, two (designated isozymes I and II) have previously been shown to sulfonate phenolic compounds exclusively and, moreover, have very similar substrate specificity patterns. The recently reported unusually efficient, rapid isozyme I-catalyzed sulfonation of 9-fluorenone oxime (Mangold, J.B., Mangold, B.L.K. and Spina, A. (1986) Biochim. Biophys. Acta 874, 37-43) was therefore unexpected and suggested that aryl oximes may represent a useful class of model compounds to probe isozymic differences in substrate steric and electronic requirements. In the present study, several mono- and diaryl oximes have been prepared and tested as potential substrates for partially purified aryl sulfotransferases I and II from rat liver cytosol. The results indicate that steric factors, specifically planarity and hydroxyl group position, appear to be important requirements for enzyme-catalyzed sulfonation. In addition, although isozymes I and II had comparable activity with diaryl oximes, some striking differences in the ability of these two isozymes to sulfonate both substituted and unsubstituted monoaryl oximes were observed. This dissimilarity is consistent with distinct differences in the active sites of these isozymes.

Fisher syndrome. An infantile case

A case of acute onset of partial ophthalmoplegia, ataxia and areflexia in a child is described. This case closely resembles those described by Fisher (Fisher syndrome). Clinical data, also in relation to the few cases previously reported, are discussed.

Protein kinase C activities are increased in rat thyroid epithelial cells expressing v-ras genes

Both cytoplasmic and membrane-bound protein kinase C activities are increased in: Harvey-Sarcoma Virus, infected thyroid epithelial cells. The cytoplasmic kinase C increase is found in the chromatographic fraction eluted at lower salt concentration (100 mM NaCl-S100), while the more acidic protein fraction eluted at higher salt concentration (35 mM NaCl-S350) is virtually absent. Although the cytoplasmic S100 fraction from the control and ras-virus infected cells display a comparable PBt2 binding activity, they are different in the Ca+2-dependence and the TPA down regulation. In addition, the membranes from the control and ras-virus infected cells are different phosphate acceptors in place of the H1 histones.

Increased adenylate cyclase activity in rat thyroid epithelial cells expressing viral ras genes

The activity of the adenylate cyclase catalytic subunit is higher in Harvey and Kirsten Murine Sarcoma Viruses-infected thyroid epithelial cells than in uninfected control cells either in the presence of Mg2+ alone or following stimulation by Mn2+ or forskolin. The higher activity is associated with an increased cAMP cellular content. The Gpp(NH)p and F- anion are more effective positive modulators in the control than in the virus infected cells: these results exclude therefore that the ras p21 proteins can act as the G-protein alpha-subunit and suggest that they negatively interfere with the G-protein modulation of the adenylate cyclase system.

Rat liver aryl sulfotransferase-catalyzed sulfation and rearrangement of 9-fluorenone oxime

The role of hepatic cytosolic aryl sulfotransferase (3'-phosphoadenylylsulfate:phenol sulfotransferase, EC 2.8.2.1) in the enzymic rearrangement of 9-fluorenone oxime to phenanthridone was investigated. 9-Fluorenone oxime was found to be an excellent substrate for a partially purified rat liver aryl sulfotransferase preparation. This compound was in fact superior to 2-naphthol, the standard assay substrate. This is the first reported observation of aryl oxime sulfation by the aryl sulfotransferases. 9-Fluorenone oxime sulfation exhibited pronounced substrate inhibition at high substrate concentrations. However, despite virtually complete conversion of 9-fluorenone oxime to the corresponding N-O-sulfate conjugate in enzyme incubation mixtures, only small amounts of rearrangement product were detected after long-term incubations. In addition, 9-fluorenone oxime-O-sulfonic acid was chemically synthesized and tested for stability. The results showed that rearrangement was pH-dependent and occurred slowly over several hours. It is therefore concluded that aryl sulfotransferase-catalyzed sulfation likely plays an important role in the in vitro and in vivo disposition of 9-fluorenone oxime. Moreover, sulfation facilitates the Beckmann-like conversion of 9-fluorenone oxime to phenanthridone. Sulfation alone, however, appears insufficient to account for all of the previously reported in vitro and in vivo rearrangement.

Adriamycin causes hyperlipemia as a consequence of nephrotoxicity

Adriamycin induced hyperlipemia: its features and mechanism(s) in rats were investigated. Massive hyperlipemia occurred 14-21 days after a single dose of adriamycin (7.5 mg/kg i.v.). All lipoprotein fractions were affected. Mild but significant changes in tissues were observed (liver and intestine triglycerides and kidney phospholipids were reduced). Lipid synthesis and secretion was decreased, as shown by the Triton WR1339 test 7 days after treatment, but subsequently returned to normal. Mitochondrial oxidation of long-chain fatty acids was markedly reduced in kidney, and a slight reduction was also observed in heart. Lipoprotein lipase activity was reduced in adipose tissue. These results suggest that adriamycin hyperlipemia is due to reduced lipid storage and utilization. Carnitine did not counteract hyperlipemia and proteinuria after adriamycin. Analogies to hyperlipemia following puromycin aminonucleoside-induced nephrotoxicity are discussed.

A stimulating effect of guanyl nucleotides on the rat-liver soluble cyclic GMP high-affinity phosphodiesterase activity

The high affinity (low Km) cyclic GMP phosphodiesterase (PDE) is activated by GTP, while the cyclic AMP PDE is not. GTP and its hydrolysis-resistant analogue, guanylylimidodiphosphate (GppNHp), display a half-maximal stimulating effect at almost the same concentration (5 X 10(-6) M). The GTP stimulating effect is not observed when the socalled cyclic GMP low affinity (high Km) PDE is operative. GTP cooperates with the increase of the substrate concentration on removing the IBMX inhibitory effect. The isolation through a classical chromatographic procedure on a DEAE-cellulose column, of a PDE fraction specific for cyclic GMP, results in the loss of the GTP stimulating effect.

[Morphologic and biologic properties of diphtherroid organisms (LDC) isolated in leprosy]

Acid-alcohol-fast bacteria are not always detectable in all leprosy lesions. Non acid-fast microorganisms may be associated with acid-fast bacteria. The most frequently isolated strains from leprosy lesions are non acid-fast bacteria, morphologically related to C. diptheirae. Hence their designation as diphtheroïds or LDC (leprosy derived corynebacteria). Their antigenic structure is more closely related to M. leprae and other mycobacteria than to classical corynebacteria. This leads to the hypothesis of a potential role in the pathogenesis of leprosy and their use as an antigen for skin tests by leprosy patients.