Toll-like Receptor 4 Activation Promotes Cardiac Arrhythmias By Decreasing The Transient Outward Potassium Current (ito) Through An Irf3-dependent And Myd88-independent Pathway.

Cardiac arrhythmias are one of the main causes of death worldwide. Several studies have shown that inflammation plays a key role in different cardiac diseases and Toll-like receptors (TLRs) seem to be involved in cardiac complications. In the present study, we investigated whether the activation of TLR4 induces cardiac electrical remodeling and arrhythmias, and the signaling pathway involved in these effects. Membrane potential was recorded in Wistar rat ventricle. Ca(2+) transients, as well as the L-type Ca(2+) current (ICaL) and the transient outward K(+) current (Ito), were recorded in isolated myocytes after 24 h exposure to the TLR4 agonist, lipopolysaccharide (LPS, 1 μg/ml). TLR4 stimulation in vitro promoted a cardiac electrical remodeling that leads to action potential prolongation associated with arrhythmic events, such as delayed afterdepolarization and triggered activity. After 24 h LPS incubation, Ito amplitude, as well as Kv4.3 and KChIP2 mRNA levels were reduced. The Ito decrease by LPS was prevented by inhibition of interferon regulatory factor 3 (IRF3), but not by inhibition of interleukin-1 receptor-associated kinase 4 (IRAK4) or nuclear factor kappa B (NF-κB). Extrasystolic activity was present in 25% of the cells, but apart from that, Ca(2+) transients and ICaL were not affected by LPS; however, Na(+)/Ca(2+) exchanger (NCX) activity was apparently increased. We conclude that TLR4 activation decreased Ito, which increased AP duration via a MyD88-independent, IRF3-dependent pathway. The longer action potential, associated with enhanced Ca(2+) efflux via NCX, could explain the presence of arrhythmias in the LPS group.

Analysis Of The Contribution Of Immunologically-detectable Her2, Steroid Receptors And Of The Triple-negative" Tumor Status To Disease-free And Overall Survival Of Women With Epithelial Ovarian Cancer."

We assessed associations between steroid receptors including: estrogen-alpha, estrogen-beta, androgen receptor, progesterone receptor, the HER2 status and triple-negative epithelial ovarian cancer (ERα-/PR-/HER2-; TNEOC) status and survival in women with epithelial ovarian cancer. The study included 152 women with primary epithelial ovarian cancer. The status of steroid receptor and HER2 was determined by immunohistochemistry. Disease-free and overall survival were calculated and compared with steroid receptor and HER2 status as well as clinicopathological features using the Cox Proportional Hazards model. A mean follow-up period of 43.6 months (interquartile range=41.4 months) was achieved where 44% of patients had serous tumor, followed by mucinous (23%), endometrioid (9%), mixed (9%), undifferentiated (8.5%) and clear cell tumors (5.3%). ER-alpha staining was associated with grade II-III tumors. Progesterone receptor staining was positively associated with a Body Mass Index≥25. Androgen receptor positivity was higher in serous tumors. In stand-alone analysis of receptor contribution to survival, estrogen-alpha positivity was associated with greater disease-free survival. However, there was no significant association between steroid receptor expression, HER2 status, or TNEOC status, and overall survival. Although estrogen-alpha, androgen receptor, progesterone receptor and the HER2 status were associated with key clinical features of the women and pathological characteristics of the tumors, these associations were not implicated in survival. Interestingly, women with TNEOC seem to fare the same way as their counterparts with non-TNEOC.

Fluorescence, Aggregation Properties And Ft-ir Microspectroscopy Of Elastin And Collagen Fibers.

Histological and histochemical observations support the hypothesis that collagen fibers can link to elastic fibers. However, the resulting organization of elastin and collagen type complexes and differences between these materials in terms of macromolecular orientation and frequencies of their chemical vibrational groups have not yet been solved. This study aimed to investigate the macromolecular organization of pure elastin, collagen type I and elastin-collagen complexes using polarized light DIC-microscopy. Additionally, differences and similarities between pure elastin and collagen bundles (CB) were investigated by Fourier transform-infrared (FT-IR) microspectroscopy. Although elastin exhibited a faint birefringence, the elastin-collagen complex aggregates formed in solution exhibited a deep birefringence and formation of an ordered-supramolecular complex typical of collagen chiral structure. The FT-IR study revealed elastin and CB peptide NH groups involved in different types of H-bonding. More energy is absorbed in the vibrational transitions corresponding to CH, CH2 and CH3 groups (probably associated with the hydrophobicity demonstrated by 8-anilino-1-naphtalene sulfonic acid sodium salt [ANS] fluorescence), and to νCN, δNH and ωCH2 groups of elastin compared to CB. It is assumed that the α-helix contribution to the pure elastin amide I profile is 46.8%, whereas that of the B-sheet is 20% and that unordered structures contribute to the remaining percentage. An FT-IR profile library reveals that the elastin signature within the 1360-1189cm(-1) spectral range resembles that of Conex-Toray aramid fibers.

Strict Criteria For Selection Of Laparoscopy For Women With Adnexal Mass.

We compared the indication of laparoscopy for treatment of adnexal masses based on the risk scores and tumor diameters with the indication based on gynecology-oncologists' experience. This was a prospective study of 174 women who underwent surgery for adnexal tumors (116 laparotomies, 58 laparoscopies). The surgeries begun and completed by laparoscopy, with benign pathologic diagnosis, were considered successful. Laparoscopic surgeries that required conversion to laparotomy, led to a malignant diagnosis, or facilitated cyst rupture were considered failures. Two groups were defined for laparoscopy indication: (1) absence of American College of Obstetrics and Gynecology (ACOG) guideline for referral of high-risk adnexal masses criteria (ACOG negative) associated with 3 different tumor sizes (10, 12, and 14 cm); and (2) Index of Risk of Malignancy (IRM) with cutoffs at 100, 200, and 300, associated with the same 3 tumor sizes. Both groups were compared with the indication based on the surgeon's experience to verify whether the selection based on strict rules would improve the rate of successful laparoscopy. ACOG-negative and tumors ≤10 cm and IRM with a cutoff at 300 points and tumors ≤10cm resulted in the same best performance (78% success = 38/49 laparoscopies). However, compared with the results of the gynecology-oncologists' experience, those were not statistically significant. The selection of patients with adnexal mass to laparoscopy by the use of the ACOG guideline or IRM associated with tumor diameter had similar performance as the experience of gynecology-oncologists. Both methods are reproducible and easy to apply to all women with adnexal masses and could be used by general gynecologists to select women for laparoscopic surgery; however, referral to a gynecology-oncologist is advisable when there is any doubt.

Elevated Cetp Activity During Acute Phase Of Myocardial Infarction Is Independently Associated With Endothelial Dysfunction And Adverse Clinical Outcome.

Recent data suggests that cholesteryl ester transfer protein (CETP) activity may interact with acute stress conditions via inflammatory-oxidative response and thrombogenesis. We investigated this assumption in patients with ST-elevation myocardial infarction (STEMI). Consecutive patients with STEMI (n = 116) were enrolled <24-h of symptoms onset and were followed for 180 days. Plasma levels of C-reactive protein (CRP), interleukin-2 (IL-2), tumor necrosis factor (TNFα), 8-isoprostane, nitric oxide (NOx) and CETP activity were measured at enrollment (D1) and at fifth day (D5). Flow-mediated dilation (FMD) was assessed by ultrasound and coronary thrombus burden (CTB) was evaluated by angiography. Neither baseline nor the change of CETP activity from D1 to D5 was associated with CRP, IL-2, TNFα, 8-isoprostane levels or CTB. The rise in NOx from D1 to D5 was inferior [3.5(-1; 10) vs. 5.5(-1; 12); p < 0.001] and FMD was lower [5.9(5.5) vs. 9.6(6.6); p = 0.047] in patients with baseline CETP activity above the median value than in their counterparts. Oxidized HDL was measured by thiobarbituric acid reactive substances (TBARS) in isolated HDL particles and increased from D1 to D5, and remaining elevated at D30. The change in TBARS content in HDL was associated with CETP activity (r = 0.72; p = 0.014) and FMD (r = -0.61; p = 0.046). High CETP activity at admission was associated with the incidence of sudden death and recurrent MI at 30 days (OR 12.8; 95% CI 1.25-132; p = 0.032) and 180 days (OR 3.3; 95% CI 1.03-10.7; p = 0.044). An enhanced CETP activity during acute phase of STEMI is independently associated with endothelial dysfunction and adverse clinical outcome.

Nitric Oxide-releasing Poly(vinyl Alcohol) Film For Increasing Dermal Vasodilation.

Pathological conditions associated with the impairment of nitric oxide (NO) production in the vasculature, such as Raynaud's syndrome and diabetic angiopathy, have stimulated the development of new biomaterials capable of delivering NO topically. With this purpose, we modified poly(vinyl-alcohol) (PVA) by chemically crosslinking it via esterification with mercaptosuccinic acid. This reaction allowed the casting of sulfhydrylated PVA (PVA-SH) films. Differential scanning calorimetry and X-ray diffractometry showed that the crosslinking reaction completely suppressed the crystallization of PVA, leading to a non-porous film with a homogeneous distribution of -SH groups. The remaining free hydroxyl groups in the PVA-SH network conferred partial hydrophylicity to the material, which was responsible for a swelling degree of ca. 110%. The PVA-SH films were subjected to an S-nitrosation reaction of the -SH groups, yielding a PVA containing S-nitrosothiol groups (PVA-SNO). Amperometric and chemiluminescence measurements showed that the PVA-SNO films were capable of releasing NO spontaneously after immersion in physiological medium. Laser Doppler-flowmetry, used to assess the blood flow in the dermal microcirculation, showed that the topical application of hydrated PVA-SNO films on the health skin led to a dose- and time-dependent increase of more than 5-fold in the dermal baseline blood flow in less than 10min, with a prolonged action of more than 4h during continuous application. These results show that PVA-SNO films might emerge as a new material with potential for the topical treatment of microvascular skin disorders.

Sorghum Flour Fractions: Correlations Among Polysaccharides, Phenolic Compounds, Antioxidant Activity And Glycemic Index.

Nutrients composition, phenolic compounds, antioxidant activity and estimated glycemic index (EGI) were evaluated in sorghum bran (SB) and decorticated sorghum flour (DSF), obtained by a rice-polisher, as well as whole sorghum flour (WSF). Correlation between EGI and the studied parameters were determined. SB presented the highest protein, lipid, ash, β-glucan, total and insoluble dietary fiber contents; and the lowest non-resistant and total starch contents. The highest carbohydrate and resistant starch contents were in DSF and WSF, respectively. Phenolic compounds and antioxidant activities were concentrated in SB. The EGI values were: DSF 84.5±0.41; WSF 77.2±0.33; and SB 60.3±0.78. Phenolic compounds, specific flavonoids and antioxidant activities, as well as total, insoluble and soluble dietary fiber and β-glucans of sorghum flour samples were all negatively correlated to EGI. RS content was not correlated to EGI.

Production Of Microparticles With Gelatin And Chitosan.

In the past few decades, the textile industry has significantly increased investment in research to develop functional fabrics, with a special focus on those aggregating values. Such fabrics can exploit microparticles inferior to 100 μm, such as those made by complex coacervation in their creation. The antimicrobial properties of chitosan can be attributed to these microparticles. Developing particles with uniform structure and properties would facilitate the control for the eventual release of the core material. Thus, a complex coacervation between gelatin and chitosan was studied, and the optimal conditions were replicated in the encapsulation of limonene. Spherical particles formed had an average diameter (D3,2) of 30 μm and were prepared with 89.7% efficiency. Cross-linking of these microparticles using glutaraldehyde and tripolyphosphate was carried out before spray drying. After drying, microparticles cross-linked with glutaraldehyde were oxidized and clustered and those that were cross-linked with tripolyphosphate resisted drying and presented a high yield.

Plastias de estenoses de intestino delgado na doença de Crohn: resultados imediatos e tardios

BACKGROUND: Strictureplasty is an alternative surgical procedure for Crohn?s disease, particulary in patients with previous resections or many intestinal stenosis. AIM: To analyze surgical complications and clinical follow-up in patients submitted to strictureplasty secondary to Crohn?s disease. METHODS: Twenty-eight patients (57.1% male, mean age 33.3 years, range 16-54 years) with Crohn?s disease and intestinal stenosis (small bowel, ileocecal region and ileocolic anastomosis) were submitted to strictureplasty, at one institution, between September 1991 and May 2004. Thirteen patients had previous intestinal resections. The mean follow-up was 58.1 months. A total of 116 strictureplasties were done (94 Heineke-Mikulicz - 81%, 15 Finney - 13%, seven side-to-side ileocolic strictureplasty - 6%). Three patients were submitted to strictureplasty at two different surgical procedures and two in three procedures. RESULTS: Regarding to strictureplasty, postoperative complication rate was 25% and mortality was 3.6%. Early local complication rate was 57.1%, with three suture leaks (10.7%) and late complication was present in two patients, both with incisional hernial and enterocutaneous fistulas (28.6%). Patients remained hospitalized during a medium time of 12.4 days. Clinical and surgical recurrence rates were 63% and 41%, respectively. Among the patients submitted to another surgery, two patients had two more operations and one had three. Recurrence rate at strictureplasty site was observed in 3.5%, being Finney technique the commonest one. Presently, 19 patients had been asymptomatic with the majority of them under medical therapy. CONCLUSION: Strictureplasties have low complication rates, in spite of having been done at compromised site, with long term pain relief. Considering the clinical course of Crohn?s disease, with many patients being submitted to intestinal resections, strictureplasties should be considered as an effective surgical treatment to spare long intestinal resections.

Desmoid tumor in patients with familial adenomatous polyposis

CONTEXT: Desmoid tumors constitute one of the most important extraintestinal manifestations of familial adenomatous polyposis. The development of desmoids is responsible for increasing morbidity and mortality rates in cases of familial adenomatous polyposis. OBJECTIVES: To evaluate the occurrence of desmoid tumors in familial adenomatous polyposis cases following prophylactic colectomy and to present patient outcome. METHODS: Between 1984 and 2008, 68 patients underwent colectomy for familial adenomatous polyposis at the School of Medical Sciences Teaching Hospital, University of Campinas, SP, Brazil. Desmoid tumors were found in nine (13.2%) of these patients, who were studied retrospectively by consulting their medical charts with respect to clinical and surgical data. RESULTS: Of nine patients, seven (77.8%) were submitted to laparotomy for tumor resection. Median age at the time of surgery was 33.9 years (range 22-51 years). Desmoid tumors were found in the abdominal wall in 3/9 cases (33.3%) and in an intra-abdominal site in the remaining six cases (66.7%). Median time elapsed between ileal pouch-anal anastomosis and diagnosis of desmoid tumor was 37.5 months (range 14-60 months), while the median time between colectomy with ileorectal anastomosis and diagnosis was 63.7 months (range 25-116 months). In 6/9 (66.7%) patients with desmoid tumors, the disease was either under control or there was no evidence of tumor recurrence at a follow-up visit made a mean of 63.1 months later (range 12-240 months). CONCLUSIONS: Desmoid tumors were found in 13.2% of cases of familial adenomatous polyposis following colectomy; therefore, familial adenomatous polyposis patients should be followed-up and surveillance should include abdominal examination to detect signs and symptoms. Treatment options include surgery and clinical management with antiestrogens, antiinflammatory drugs or chemotherapy.

Espectroscopia de Ressonância Magnética Nuclear de 13C no estudo de rotas biossintéticas de produtos naturais

During the last five decades, as a result of an interaction between natural product chemistry, synthetic organic chemistry, molecular biology and spectroscopy, scientists reached an extraordinary level of comprehension about the natural processes by which living organisms build up complex molecules. In this context, 13C nuclear magnetic resonance spectroscopy, allied with isotopic labeling, played a determinant role. Nowadays, the widespread use of modern NMR techniques allows an even more detailed picture of the biochemical steps by accurate manipulation of the atomic nuclei. This article focuses on the development of such techniques and their impact on biosynthetic studies.