Myoinositol and methyl stearate increases rifampicin susceptibility among drug-resistant Mycobacterium tuberculosis expressing Rv1819c.

The alarming increase in multidrug resistance, which includes Bedaquiline and Delamanid, stumbles success in Tuberculosis treatment outcome. Mycobacterium tuberculosis gains resistance to rifampicin, which is one of the less toxic and potent anti-TB drugs, through genetic mutations predominantly besides efflux pump mediated drug resistance. In recent decades, scientific interventions are being carried out to overcome this hurdle using novel approaches to save this drug by combining it with other drugs/molecules or by use of high dose rifampicin. This study reports five small molecules namely Ellagic acid, Methyl Stearate, Myoinositol, Rutin, and Shikimic acid that exhibit synergistic inhibitory activity with rifampicin against resistant TB isolates. In-silico examinations revealed possible blocking of Rv1819c-an ABC transporter efflux pump that was known to confer resistance in M. tuberculosis to rifampicin. The synergistic anti-TB activity was assessed using a drug combination checkerboard assay. Efflux pump inhibition activity of ellagic acid, myoinositol, and methyl stearate was observed through ethidium bromide accumulation assay in the drug-resistant M. tuberculosis clinical strains and recombinant Mycobacterium smegmatis expressing Rv1819c in coherence with the significant reduction in the minimum inhibitory concentration of rifampicin. Cytotoxicity of the active efflux inhibitors was tested using in silico and ex vivo methods. Myoinositol and methyl stearate were completely non-toxic to the hematological and epithelial cells of different organs under ex vivo conditions. Based on these findings, these molecules can be considered for adjunct TB therapy; however, their impact on other drugs of anti-TB regimen needs to be tested.

Bacteria-derived long chain fatty acid exhibits anti-inflammatory properties in colitis.

OBJECTIVE: Data from clinical research suggest that certain probiotic bacterial strains have the potential to modulate colonic inflammation. Nonetheless, these data differ between studies due to the probiotic bacterial strains used and the poor knowledge of their mechanisms of action. DESIGN: By mass-spectrometry, we identified and quantified free long chain fatty acids (LCFAs) in probiotics and assessed the effect of one of them in mouse colitis. RESULTS: Among all the LCFAs quantified by mass spectrometry in Escherichia coli Nissle 1917 (EcN), a probiotic used for the treatment of multiple intestinal disorders, the concentration of 3-hydroxyoctadecaenoic acid (C18-3OH) was increased in EcN compared with other E. coli strains tested. Oral administration of C18-3OH decreased colitis induced by dextran sulfate sodium in mice. To determine whether other bacteria composing the microbiota are able to produce C18-3OH, we targeted the gut microbiota of mice with prebiotic fructooligosaccharides (FOS). The anti-inflammatory properties of FOS were associated with an increase in colonic C18-3OH concentration. Microbiota analyses revealed that the concentration of C18-3OH was correlated with an increase in the abundance in Allobaculum, Holdemanella and Parabacteroides. In culture, Holdemanella biformis produced high concentration of C18-3OH. Finally, using TR-FRET binding assay and gene expression analysis, we demonstrated that the C18-3OH is an agonist of peroxisome proliferator activated receptor gamma. CONCLUSION: The production of C18-3OH by bacteria could be one of the mechanisms implicated in the anti-inflammatory properties of probiotics. The production of LCFA-3OH by bacteria could be implicated in the microbiota/host interactions.

Synthesis and application of 188Re-MN-16ET/Lipiodol in a hepatocellular carcinoma animal model.

INTRODUCTION: Hepatocellular carcinoma is the most common form of primary hepatic carcinoma. A new N(2)S(2) tetradentate ligand, N-[2-(triphenylmethyl)thioethyl]-3-aza-19-ethyloxycarbonyl-3-[2-(triphenylmethyl)thioethyl]octadecanoate (H(3)MN-16ET), was introduced and labeled with (188)Re to create (188)Re-MN-16ET in the Lipiodol phase. The potential of (188)Re-MN-16ET/Lipiodol for hepatoma therapy was evaluated in a hepatocellular carcinoma animal model of Sprague-Dawley rats implanted with the N1S1 cell line. METHODS: Synthesis of H(3)MN-16ET was described, and characterization was identified by infrared, nuclear magnetic resonance and mass spectra. We compared the effects of transchelating agents (glucoheptonate or tartaric acid) and a reducing agent (stannous chloride) on the complexing of (188)Re-perrhenate and H(3)MN-16ET. Twenty-four rats implanted with hepatoma were injected with 3.7 MBq/0.1 ml of (188)Re-MN-16ET/Lipiodol or (188)Re-MN-16ET via transcatheter arterial embolization. Biodistribution experiments and single-photon emission computed tomography imaging were performed to investigate tumor accumulation. RESULTS: H(3)MN-16ET was proved to easily conjugate with the Re isotope and showed good solubility in Lipiodol. The radiochemical purity of (188)Re-MN-16ET/Lipiodol with 10 mg tartaric acid and stannous chloride was shown to be more than 90%. The major distribution sites of (188)Re-MN-16ET in Sprague-Dawley rats were hepatoma and the liver. However, the radioactivity at the tumor site postadministered with (188)Re-MN-16ET was quickly decreased from 9.15±0.23 (at 1 h) to 2.71%±0.18% of injected dose/g (at 48 h). The biodistribution and micro-single-photon emission computed tomography/computed tomography image data showed that (188)Re-MN-16ET/Lipiodol was selectively retained at the tumor site, with 11.55±1.44, 13.16±1.46 and 10.67%±0.95% of injected dose/g at 1, 24 and 48 h postinjection, respectively. The radioactivity in normal liver tissue was high but significantly lower than that of the tumors. CONCLUSION: H(3)MN-16ET is a suitable tetradentate ligand for (188)Re labeling. From the animal data, we suggest that (188)Re-MN-16ET/Lipiodol has the potential to be a therapeutic radiopharmaceutical for hepatoma treatment.

Prevention of carcinogenesis and inhibition of breast cancer tumor burden by dietary stearate.

Previous studies have shown that stearate (C18:0), a dietary long-chain saturated fatty acid, inhibits breast cancer cell neoplastic progression; however, little is known about the mechanism modulating these processes. We demonstrate that stearate, at physiological concentrations, inhibits cell cycle progression in human breast cancer cells at both the G(1) and G(2) phases. Stearate also increases cell cycle inhibitor p21(CIP1/WAF1) and p27(KIP1) levels and concomitantly decreases cyclin-dependent kinase 2 (Cdk2) phosphorylation. Our data also show that stearate induces Ras- guanosine triphosphate formation and causes increased phosphorylation of extracellular signal-regulated kinase (pERK). The MEK1 inhibitor, PD98059, reversed stearate-induced p21(CIP1/WAF1) upregulation, but only partially restored stearate-induced dephosphorylation of Cdk2. The Ras/mitogen-activated protein kinase/ERK pathway has been linked to cell cycle regulation but generally in a positive way. Interestingly, we found that stearate inhibits both Rho activation and expression in vitro. In addition, constitutively active RhoC reversed stearate-induced upregulation of p27(KIP1), providing further evidence of Rho involvement. To test the effect of stearate in vivo, we used the N-Nitroso-N-methylurea rat breast cancer carcinogen model. We found that dietary stearate reduces the incidence of carcinogen-induced mammary cancer and reduces tumor burden. Importantly, mammary tumor cells from rats on a stearate diet had reduced expression of RhoA and B as well as total Rho compared with a low-fat diet. Overall, these data indicate that stearate inhibits breast cancer cell proliferation by inhibiting key check points in the cell cycle as well as Rho expression in vitro and in vivo and inhibits tumor burden and carcinogen-induced mammary cancer in vivo.

Efficacy of a lactylate on production performance and intestinal health of broilers during a subclinical Clostridium perfringens infection.

Clostridium perfringens, an α-toxin producing gram-positive bacterium, is an enteric pathogen for poultry. Because subclinical C. perfringens infections often result in damage of the intestinal mucosa, decreased nutrient digestion, and poor performance, efforts should be taken to find an effective strategy that controls overgrowth of C. perfringens. For this purpose, the efficacy of a sodium lauroyl lactylate (LauL) as a feed additive to prevent C. perfringens colonization in broilers was determined. First, the effect of LauL was compared with capric and lauric mono- and diglycerides (MDG) and capric and lauric free fatty acids in Clostridium-infected chickens. Clostridial lesion scoring at d 16 showed that MDG and LauL were both effective in reducing the severity of lesions. When taking into account results on BW gain and mortality, LauL was more effective than MDG. For this reason, a dose response study was made to determine the optimal dietary dosage of LauL. In this experiment, it was shown that a LauL dose higher than 0.15% should be used to expect positive effects on lesion severity and mortality. None of the LauL doses led to a significant better response on growth performance. In a third trial, efficacy of LauL was compared with commercial products that limit bacterial activity in the intestinal tract (Aromabiotic Poul 60) or coccidiosis (chemical coccidiostat, Clinacox). None of the products were able to reduce the number or severity of lesions, and no effect on production performance was observed. Thus, despite the clear positive effect seen in experiment 1, and in experiment 2 with LauL doses higher than 0.15%, supplementing this lactylate to the diet does not consistently reduce C. perfringens colonization in broiler chickens because no such effects were observed in experiment 3. These results, however, provide a scientific basis for future studies to further investigate lactylates as potential additives to reduce the severity of necrotic enteritis in broilers in a C. perfringens challenge model.

Estudo descritivo sobre a antibioticoprofilaxia na rupturaprematura pré-termo de membranas / Perinatal results of antibioticprophyxalis with erythromycin in preterm premature rupture of the membranes

Objetivo: avaliar os resultados perinatais do uso profilático de estearato de eritromicina nas pacientesinternadas na unidade de gestação alto risco da Maternidade Carmela Dutra (MCD), Florianópolis–SC, com diagnóstico de ruptura prematura pré-termo de membranas (RPM). Métodos: estudo descritivo com análise de todas as pacientes internadas com o diagnóstico de RPM e com idade gestacional entre 20 semanas e 33 semanas e cinco dias. Foram excluídas da pesquisa gestantes com históriade hipersensibilidade à eritromicina, com sinais clínicos e/ou laboratoriais de corioamnionite, que estavam emtrabalho de parto ou que faziam uso de antibióticos no momento da internação. A amostra obtida entre 1º de abril de 2007 e 15 de maio de 2008 foi de 22 pacientes. Resultados e conclusões: o tempo médio de latência foi de 12 dias. Não houve casos confirmados decorioamnionite. Uma (4,54%) gestante desenvolveu quadro de endometrite puerperal. Não houve óbitos maternos. Dois (9,09%) recém-nascidos desenvolveram sepse. A taxa de óbito neonatal foi de 13,63%. Apesarda nossa pequena casuística, o uso de eritromicina nas pacientes com RPM parece estar associado a umadiminuição na taxa de corioamnionite.

Objective: The purposes of this study were to evaluate perinatal results of the prophylactic use of erythromycin to patients admitted in the high-riskgestation unit at Carmela Dutra Maternity Hospital, Florianópolis – SC with preterm premature rupture ofmembranes (PROM). Methods: We performed a descriptive analysis ofall patients with PROM and gestational age between 20 weeks and 33 weeks plus 5 days. Patients with erythromycin allergy, with chorioamnionitis signs orwomen who already being prescribed antibiotics were excluded from this study. Enrolment was from April 1,2007, until May 15, 2008. Twenty-two women had been followed up in this study. Results and Conclusions: The medium latency period was 12 days. There was not confirmed chorioamnionitis case. The occurrence of endometritis was 4,54%. There was not maternal death. The occurrence of neonatal sepsis was 9,09% and theoccurrence of neonatal deaths was 13,63%. Despite our small casuistry, the prophylactic use of erythromycinseems to reduce the chorioamnionitis rate.

Stearate-enriched plant sterol esters lower serum LDL cholesterol concentration in normo- and hypercholesterolemic adults.

Studies in our laboratory have previously demonstrated in hamsters a superior cholesterol-lowering ability of plant sterol (PS) esters enriched in stearate compared with linoleate. We therefore conducted a randomized, double-blind, 2-group parallel, placebo-controlled study to test the cholesterol-lowering properties of stearate-enriched PS esters in normo- and hypercholesterolemic adults. Thirty-two adults, 16 per group with equal number of males and females in each group, participated in the 4-wk study. Participants consumed 3 g/d (1 g three times per day with meals) of either PS esters or placebo delivered in capsules. Serum LDL cholesterol concentration significantly decreased 0.42 mmol/L (11%) and the LDL:HDL cholesterol ratio decreased 10% with PS ester supplementation, whereas LDL particle size and lipoprotein subclass particle concentrations (as measured by NMR) were not affected. The percent change in LDL cholesterol was positively correlated with baseline lathosterol concentration (r = 0.729; P = 0.0014), indicating an association between the magnitude of LDL change and the rate of whole-body cholesterol synthesis. Serum campesterol (but not sitosterol) concentration significantly increased in the PS ester group. Serum tocopherol, retinol, and beta-carotene concentrations were not affected by PS ester supplementation. Thus, our findings demonstrate the usefulness of a novel stearate-enriched PS ester compound in decreasing LDL cholesterol in both normo- and hypercholesterolemic adults. The extent to which PS ester fatty acid composition affects intestinal micelle formation and cholesterol absorption in humans requires further study.

Dietary stearate reduces human breast cancer metastasis burden in athymic nude mice.

Stearate is an 18-carbon saturated fatty acid found in many foods in the western diet, including beef and chocolate. Stearate has been shown to have anti-cancer properties during early stages of neoplastic progression. However, previous studies have not investigated the effect of dietary stearate on breast cancer metastasis. In this study, we present evidence that exogenously supplied dietary stearate dramatically reduces the size of tumors that formed from injected human breast cancer cells within the mammary fat pads of athymic nude mice by approximately 50% and partially inhibits breast cancer cell metastasis burden in the lungs in this mouse model system. This metastatic inhibition appears to be independent of primary tumor size, as stearate fed animals that had primary tumors comparable in size to littermates fed either a safflower oil enriched diet or a low fat diet had reduced lung metastasis. Also stearate fed mice sub-groups had different primary tumor sizes but no difference in metastasis. This anti-metastasis effect may be due, at least in part, to the ability of stearate to induce apoptosis in these human breast cancer cells. Overall, this study suggests the possibility of dietary manipulation with selected long-chain saturated fatty acids such as stearate as a potential adjuvant therapeutic strategy for breast cancer patients wishing to maximize the suppression of metastatic disease.

The tandem repeated irritation test: a new method to assess prevention of irritant combination damage to the skin.

The effect of a protective cream was tested in a new tandem repeated irritation test with tandem application of 0.5% sodium lauryl sulphate (SLS) and undiluted toluene. The irritants were applied twice daily for 30 min to the ventral forearms of 20 volunteers. Irritant cutaneous reactions were quantified by a visual score, transepidermal water loss, chromametry and skin capacitance. Concurrent application of SLS/toluene induced stronger reactions than those caused by twice daily application of each irritant on its own. A protective effect of the protective cream was obtained against all treatment combinations and was significant for SLS/SLS (p < or = 0.01) and SLS/ toluene (p < or = 0.05). Our results indicate that the tandem repetitive irritation test has great potential in the evaluation of skin care products to prevent irritant contact dermatitis.

[Intra operative embolization of unresectable cerebral arterio-venous malformations. Occlusion attempt by means of a delayed polymerization mixture. Report of two cases (author's transl)]. / Embolisation per-opératoire des malformations artério-veineuses cérébrales inextirpables: tentative d'oblitération par un mélange à polymérisation retardée. A propos de deux cas.

Two cases of unresectable intra-cranial arterio-venous malformation (AVM) are reported, treated by direct intra-operative embolization. A 50% mixture of Butyl-2-Cyano-Acrylate and Mono-Iodo-Stearate of Ethyle (Duroliopaque) was used after catheterization of some of the feeding cortical arteries. No intra-operative angiography was performed. The first patient, admitted after subarachnoid hemorrhage and presenting with a mild transient right hemiparesia and aphasia, showed evidence of a left temporal AVM with a left middle cerebral artery supply and contribution from the left cerebral posterior artery. The AVM was embolized with 3 cc of the mixture. A mild aphasia occurred after surgery and completely recovered after two weeks. Roughly half of the AVM was occluded on the postoperative angiograms. The second patient suffering from a long history of seizures had a huge right frontal AVM, with a right middle cerebral artery and right anterior cerebral artery supply, and contribution from a right lenticulostriate artery, the left anterior cerebral artery and the right posterior cerebral artery. The AVM was embolized with 7 cc of the mixture. A complete palsy of the left upper limb occurred after surgery, with complete recovery after two weeks. On the post-operative angiograms, more than three fourth of the AVM was occluded.

Treatment of acute bacterial infections of the upper respiratory tract.

An open comparative study was carried out to assess the effectiveness of 4 antibiotic regimens in eradicating acute bacterial infections of the upper respiratory tract. Patients in each treatment group had similar physical parameters, severity of disease and bacterial pathogens, and were treated for 10 days with either erythromycin estolate, erythromycin stearate, ampicillin or oxytetracycline in the recommended dosage. Each patient was reviewed daily by physical examination and the bacteriological findings from throat swab and salivary washings. The results showed that erythromycin stearate produced more rapid bacterial eradication and clinical resolution of symptoms and fever than with the other antibiotic preparations, and was well tolerated by most patients.

Comparison of erythromycin ethyl succinate, stearate and estolate treatments of group A streptococcal infections of the upper respiratory tract.

The microbiologic and clinical responses of acute Group A beta-hemolytic streptococcal infections of the upper respiratory tract to oral treatment with erythromycin ethyl succinate, stearate, and estolate were studied in 303 patients. Streptococcal M and T typing was done on all positive cultures. The overall cure rate was 95.4 per cent, with no statistically significant differences in clearing organisms from the pharynx. Of the 285 cured patients who completed the prescribed follow-up period, 11 had recurrences between the 12th and 31st day after initiation of therapy, and five developed new infections. No cases of rheumatic fever or glomerulonephritis were encountered during a follow-up study. Eight gastrointestinal reactions and one transient rash occurred. Results with these forms of erythromycin compare favorably with published results for similar infections treated with oral penicillins.

Erythromycin stearate in acute maxillary sinusitis.

76 patients with acute maxillary sinusitis were treated with oral erythromycin stearate (500 mg twice or 3 times a day for 10 days). The mean concentration of erythromycin in the sinus secretion after 3-5 days' treatment was 0.6 mug/ml with the lower dosage and 1.3 mug/ml with the higher. The concentration of erythromycin in the sinus secretion was, on the average, 10-20 times higher than the minimum inhibitory concentration (MIC) for group A streptococci and pneumococci, and reached MIC values for 15-30% of 100 examined strains of Haemophilus influenzae. 81% of the patients given the smaller and 94% of those given the larger dose improved or recovered. Radiological improvement was demonstrated in both groups. The infections with H. influenzae tended to respond somewhat less to the treatment than those with pneumococci. Comparisons of the roentgen findings and the findings at aspiration showed good agreement. An extra projection taken with the patient recumbent and the affected side downwards gave no information above that obtained from the routine projections. The large dose caused side effects more often (in 17/41 patients) than the smaller one (4/35 patients). In 10 patients treatment was discontinued because of side effects; 8 of them had received the larger dose.