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Background: Wood apple (Limonia acidissima) has been reported to possess various pharmacological activities. The present study aimed to evaluate the 11 selected constituents of Wood apple (L. acidissima) as potent anti-dandruff and anti-acne agents using a molecular docking approach. Materials and Methods: The 11 selected constituents of Wood apple were studied on the molecular docking behavior of Malassezia globosa Lipase-1 and Cutibacterium acnes beta-keto acyl synthase-III enzymes by using the patchdock method. Furthermore, STITCH analysis was carried out to determine the ligand-protein interactions. STITCH analysis reveals that two ligands, namely, psoralen and umbelliferone, have exhibited interactions with both the M. globosa and P. acnes KPA 171202 proteins. Results: The docking studies revealed that isopimpinellin and saponarin exhibited the highest (ACE) atomic contact energy (-162.32 and - 318.63 kcal/mol) with that of M. globosa Lipase-1 and C. acnes beta-ketoacyl synthase-III, respectively. Conclusion: Thus, the present finding provides new knowledge for understanding the 11 selected ligands of Wood apple (L. acidissima) as potent anti-dandruff and anti-acne agents.
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Background: Cancer rates continue to climb, owing largely to the world population's aging and growth, as well as economically developing countries, a surge in cancer-causing behavior, particularly smoking. The third or fourth most prevalent type of cancer is colon cancer. Cancer of the large intestine (colon) is one of the primary causes of death from cancer. Colorectal cancer prevention is mostly based on adenomatous disease screening approaches. The cytotoxic and pharmacological properties of Phoenix pusilla are widely documented. As a result, there is little recorded evidence of its cytotoxic activity against colon cancer cells. Therefore, we planned to study the efficacy of a methanolic leaf extract of Phoenix pusilla against in vitro colon cancer cells. Aim: To evaluate the anti-cancer effects of the methanolic leaf extract of Phoenix pusilla on colon cancer cell lines. Materials and Methods: In vitro screening and anti-cancer effects of the methanolic effect of Phoenix pusilla on colon cancer cell lines were assessed by cell viability assays and cell and nuclear morphological studies. For the in vitro cell culture study, different concentrations of Phoenix pusilla leaf extract (0, 25, 50, 75, 100, 150 µg/ml) were used, and IC50 doses were calculated. Results: The results of the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay revealed that the fraction of viability cells significantly decreased in treated cells when compared to untreated control groups, was expressed as 100%, and an inhibitory concentration of µg/ml was identified. A phase-contrast microscope was used to observe cell shrinkage and cytoplasmic membrane blebbing. A fluorescent microscope was used to examine the apoptotic nuclei (internally dyed nuclei, shattered nuclei, and condensed chromatin). Conclusion: In conclusion, the present study results showed that the leaf extracts of Phoenix pusilla had a strong cytotoxic effect and induced significant apoptosis in the colon cancer cell lines at a concentration of 75 µg/ml in the 24 h incubation period. More research is needed to investigate the extract's active components as well as the molecular mechanisms underlying its anti-cancer properties.
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BACKGROUND: While existing evidence suggests less severe clinical manifestations and lower mortality are associated with the Omicron variant as compared to the Delta variant. However, these studies fail to control for differences in health systems facilities and providers. By comparing patients hospitalized on a single medical service during the Delta and Omicron surges we were able to conduct a more accurate comparison of the two varaints' clinical manifestations and outcomes. METHODS: We conducted a prospective study of 364 Omicron (BA.1) infected patients on a single hospitalist service and compared these findings to a retrospective analysis of 241 Delta variant infected patients managed on the same service. We examined differences in symptoms, laboratory measures, and clinical severity between the two variants and assessed potential risk drivers for case mortality. FINDINGS: Patients infected with Omicron were older and had more underlying medical conditions increasing their risk of death. Although they were less severely ill and required less supplemental oxygen and dexamethasone, in-hospital mortality was similar to Delta cases, 7.14% vs. 4.98% for Delta (q-value = 0.38). Patients older than 60 years or with immunocompromised conditions had much higher risk of death during hospitalization, with estimated odds ratios of 17.46 (95% CI: 5.05, 110.51) and 2.80 (1.03, 7.08) respectively. Neither vaccine history nor variant type played a significant role in case fatality. The Rothman score, NEWS-2 score, level of neutrophils, level of care, age, and creatinine level at admission were highly predictive of in-hospital death. INTERPRETATION: In hospitalized patients, the Omicron variant is less virulent than the Delta variant but is associated with a comparable mortality. Clinical and laboratory features at admission are informative about the risk of death.
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COVID-19 , Médicos Hospitalares , Humanos , Mortalidade Hospitalar , Estudos Prospectivos , Estudos Retrospectivos , SARS-CoV-2RESUMO
Background: Bunch berry (Lantana camara) is primarily composed of flavonoids and vitamin C; therefore, it has been shown to possess various medical characteristics, including the ability to relieve fever, inflammation, and urinary tract infections. Objective: In this study, we intended to assess twenty chosen constituents of Bunch berry as potent inhibitory agents of human acetylcholinesterase (hAchE), carbonic anhydrase II (hCA-II) and carboxylesterase 1 (hCES-1) employing in silico techniques. Methods: The twenty chosen Bunch berry components were examined about docking behaviour of hAchE, hCA-II and hCES-I by using the Swissdock method. Apart from to docking, Molecular physico-chemical, drug-likeness, ADME (ingesting, dispersing, metabolising, and excreting), and toxicity assessments were also performed utilising the Molinspiration, Swiss ADME, pkCSM, and STITCH web sites, correspondingly. Results: Eight ligands (40 %) have exhibited strict adherence to Lipinski's rule of five (Ro5), according to molecular physico-chemical study. Drug-likeness property analysis has shown that five ligands (25 %) of Bunch berry predicted to exhibit moderate bioactivity score against all the descriptors. ADME analysis has shown that five ligands (25 %) of Bunch berry are predicted to possess high gastrointestinal absorption property Toxicity analysis has shown that six ligands (30 %) of Bunch berry are predicted to have hERG II (Human ether-a-go-go-related gene) inhibition activity. According to the docking analysis, lantic acid has the lowest atomic binding energy for all three target enzymes, hAchE (-6.23 kcal/mol), hCA-II (-4.46 kcal/mol), and hCES-I (-5.99 kcal/mol), respectively. Conclusions: Thus the current find provides an advanced understanding the twenty selected ligands of Bunch berry as potent inhibitory agents of human acetylcholinesterase (hAchE), carbonic anhydrase II (hCA-II) and carboxylesterase 1 (hCES-1).
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Aim: To compare the effect of salivary contamination on the shear bond strength (SBS) of seventh- and eighth-generation adhesives. Materials and methods: Specimens were randomly divided into group I and group II, subdivided into three subgroups of 11 samples. Subgroup IA-seventh-generation uncontaminated (control); adhesive; air-dried; light cured. Subgroup IB-seventh-generation adhesive; saliva application, air-dried; light cured. Subgroup IC-seventh-generation adhesive; saliva application, air-dried, reapplication of adhesive, air-dried, light cured. Subgroup IIA- eighth-generation uncontaminated (control); adhesive, air-dried; light cured. Subgroup IIB- eighth-generation adhesive; saliva application, air-dried; light cured. Subgroup IIC-eighth-generation adhesive, saliva application, air-dried, reapplication of adhesive, air-dried; light cured. Following bonding procedure, composite resin restoration was done and subjected to SBS analysis. Results: Mean SBS of eighth-generation adhesive was higher compared to seventh with and without saliva contamination. Reduction of SBS in seventh- and eighth-generation after saliva contamination was regained by reapplication of adhesive, which was less compared to the control [statistically significant (p < 0.05) for seventh and statistically not significant for eighth-generations]. Conclusion: The eighth-generation adhesives show better SBS with and without saliva contamination and reapplication of eighth-generation adhesives significantly improved the SBS close to the control. Clinical significance: Single-step self-etch adhesives are the adhesives which are currently used for bonding composite restorations to dentin. The adhesive bond strength can be adversely affected by moisture contamination, especially by saliva, which can lead to failure of restoration. So, it is imperative to study a material which gives better bond strength and is less affected by salivary contamination and effect of decontamination to regain the bond strength. The study concluded that eighth-generation adhesives showed higher mean SBS with and without saliva contamination and reapplication of eighth-generation adhesives significantly improved the bond strength close to the control group. How to cite this article: Mohan MC, Geetha P, Soman D, et al. The Effect of Salivary Contamination on the Shear Bond Strength of Seventh- and Eighth-generation Adhesive Systems. Int J Clin Pediatr Dent 2023;16(S-1):S63-S66.
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Endothelium of blood vessels is continuously exposed to various hemodynamic forces. Flow-mediated epigenetic plasticity regulates vascular endothelial function. Recent studies have highlighted the significant role of mechanosensing-related epigenetics in localized endothelial dysfunction and the regional susceptibility for lesions in vascular diseases. In this article, we review the epigenetic mechanisms such as DNA de/methylation, histone modifications, as well as non-coding RNAs in promoting endothelial dysfunction in major arterial and venous diseases, consequent to hemodynamic alterations. We also discuss the current challenges and future prospects for the use of mechanoepigenetic mediators as biomarkers of early stages of vascular diseases and dysregulated mechanosensing-related epigenetic regulators as therapeutic targets in various vascular diseases.
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Epigênese Genética , Hemodinâmica , Doenças Vasculares/genética , Doenças Vasculares/metabolismo , Animais , Aterosclerose/metabolismo , Biomarcadores/metabolismo , Metilação de DNA , Células Endoteliais/patologia , Endotélio Vascular/metabolismo , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Camundongos , Processamento de Proteína Pós-TraducionalRESUMO
Given the high prevalence of chronic venous diseases (CVD), defining criteria to screen patients who are in need for intervention is attaining primacy. An important clinical criterion for treating CVD is incompetence of larger veins. We have assessed the association of size of afflicted veins with disease severity in patients with CVD to define an acceptable criterion to identify patients who need intervention. Demographic characteristics and risk factors were recorded from 6350 patients. Based on physical examination and venous duplex ultrasound study, patients were classified into clinical severity, etiology, anatomy, and pathophysiology (CEAP) classes and grouped according to the size of the veins which had varicosities. Patients with reflux in smaller veins (vein size <4 mm diameter) were considered as type I and those with varicosities in truncal veins (>4 mm diameter) as type II. Risk ratio was determined by multivariate regression analysis. About 47.67% of patients in this study were found to have CEAP class 3 disease. Compared with varicose veins of large truncal veins, patients with varicosities in smaller superficial veins had 2.85-fold ( p < 0.01) more risk of edema and 5.71-fold ( p < 0.01) higher prevalence of hyperpigmentation. Varicosities in small superficial veins were associated with higher risk of ulceration (odds ratio 3.93, 95% confidence interval 2.51-6.18) compared with truncal vein reflux. Our study reveals that presence of small varicose veins in patients without truncal saphenous reflux involvement is associated with severe manifestations of venous insufficiency such as edema and skin lesions even in the absence of varicosities in truncal saphenous veins.
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INTRODUCTION: Hereditary spherocytosis (HS) is the most common inherited hemolytic anemia with heterogeneous clinico-laboratory manifestations. We evaluated the flow-cytometric tests: eosin-5'-maleimide (EMA) and flow-cytometric osmotic fragility test (FOFT) and the conventional osmotic fragility tests (OFT) for the diagnosis of hereditary spherocytosis (HS). METHODS: One hundred two suspected HS patients underwent EMA, FOFT, incubated OFT (IOFT), and room temperature OFT (RT-OFT). In addition, 10 cases of immune hemolytic anemia (IHA) were included, and performance of the above 4 tests was evaluated. For EMA and FOFT, 5 normal controls were assessed together with the patients and cutoffs were calculated using receiver-operator-characteristics curve (ROC) analysis. RESULTS: The best cutoff for %EMA decrease was 12.5%, and for FOFT, %residual red cells (%RRC) was 25.6%. The sensitivity and specificity of RT-OFT was 62.06% and 86.3%, respectively, while that of IOFT was 79.31% and 87.67%, respectively. Both flow cytometric tests performed better. Sensitivity and specificity of EMA was 86.2% and 93.9% respectively, and that of FOFT was 96.6% and 98.63%, respectively. The combination of the FOFT with IOFT or EMA dye-binding test yields a sensitivity of 100%, but with EMA, it had a higher specificity. Hb/MCHC was a predictor of the severity of the disease while %EMA decrease and %RRC did not correlate with severity of the disease. CONCLUSION: Flow-cytometric osmotic fragility test is the best possible single test followed by EMA for diagnosis of HS. A combination of FOFT and EMA can correctly diagnose 100% patients. These tests are likely to replace conventional OFTs in future.
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Amarelo de Eosina-(YS)/análogos & derivados , Citometria de Fluxo/métodos , Fragilidade Osmótica , Esferocitose Hereditária/diagnóstico , Adulto , Idoso , Amarelo de Eosina-(YS)/metabolismo , Eritrócitos , Humanos , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Biofeedback therapy (BFT) is an established treatment for fecal incontinence (FI), with access often being restricted to tertiary centers due to resources and the perceived requirement for high-intensity regimes. However, the optimal regime remains unknown. We evaluated outcomes from our low-intensity integrated BFT program in a secondary care center. METHODS: Outcomes of our BFT service for FI were evaluated retrospectively. Response was defined by ≥50% improvement in FI frequency from baseline or complete continence. Responders were compared to non-responders for factors including symptoms, manometry data, sphincter exercise technique and duration of practice, and the number and frequency of sessions. Where patients dropped out, outcomes and the reason for dropout were obtained retrospectively. KEY RESULTS: Fecal incontinence patients (n=205, median 62 years, 72% female) attended a median (IQR) 3 (2) BFT sessions with 55 (36) days between visits. Overall, 146/205 (71%) responded with 97/205 (47%) achieving continence. Fecal incontinence frequency improved dramatically in completed cases (P=0.000). While non-response was associated with males (P=0.03) and dropout (P=0.000), "good" anal sphincter exercise technique (P=0.008) and longer in-home practice (P=0.007) and more sessions (P=0.04) were associated with response. Dropout rate was 80/205 (39%), with the reason for dropout being obtained in 80%. CONCLUSIONS & INFERENCES: Despite low-intensity BFT, comparable outcomes to data from tertiary centers were achieved. Our data emphasize the importance of technique and in-home practice of anal sphincter exercises. Customizing BFT intensity based on predictive factors and encouraging in-home practice may optimize outcomes, reduce dropout rates, and rationalize resources.
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Canal Anal/fisiologia , Biorretroalimentação Psicológica/métodos , Terapia por Exercício/métodos , Incontinência Fecal/diagnóstico , Incontinência Fecal/terapia , Serviços de Assistência Domiciliar , Idoso , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Varicose veins of lower extremities are a heritable common disorder. Mechanisms underlying its pathogenesis are still vague. Structural failures such as valve weakness and wall dilatation in saphenous vein result in venous retrograde flow in lower extremities of body. Reflux of blood leads to distal high venous pressure resulting in distended veins. In an earlier study, we observed a positive association between c.-512C>T FoxC2 gene polymorphism and upregulated FoxC2 expression in varicose vein specimens. FoxC2 overexpression in vitro in venous endothelial cells resulted in the elevated mRNA expression of arterial endothelial markers such as Delta-like ligand 4 (Dll4) and Hairy/enhancer-of-split related with YRPW motif protein 2 (Hey2). We hypothesized that an altered FoxC2-Dll4 signaling underlies saphenous vein wall remodeling in patients with varicose veins. Saphenous veins specimens were collected from 22 patients with varicose veins and 20 control subjects who underwent coronary artery bypass grafting. Tissues were processed for paraffin embedding and sections were immunostained for Dll4, Hey2, EphrinB2, α-SMA, Vimentin, and CD31 antigens and examined under microscope. These observations were confirmed by quantitative real-time PCR and western blot analysis. An examination of varicose vein tissue specimens by immunohistochemistry indicated an elevated expression of Notch pathway components, such as Dll4, Hey2, and EphrinB2, and smooth muscle markers, which was further confirmed by gene and protein expression analyses. We conclude that the molecular alterations in Dll4-Hey2 signaling are associated with smooth muscle cell hypertrophy and hyperplasia in varicose veins. Our observations substantiate a significant role for altered FoxC2-Dll4 signaling in structural alterations of saphenous veins in patients with varicose veins.
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Fatores de Transcrição Forkhead/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Varizes/genética , Remodelação Vascular/genética , Actinas/genética , Actinas/metabolismo , Adulto , Idoso , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Western Blotting , Efrina-B2/genética , Efrina-B2/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Músculo Liso/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veia Safena/metabolismo , Veia Safena/patologia , Veia Safena/fisiopatologia , Transdução de Sinais/genética , Regulação para Cima/genética , Varizes/metabolismo , Adulto JovemRESUMO
Varicose veins (VVs) are generally characterized by their elongated, twisted, bulging, superficial appearance on the lower extremities and usually present with acute or chronic venous diseases. Despite diagnostic and surgical advances in the management of VV, patients suffer from post-therapeutic complications and recurrence. We present findings from a retrospective study of a modified treatment modality in patients with varicose veins who attended St. Thomas Institute of Research on Venous Diseases, Changanassery, Kerala. The hospital caters to patients from India and outside. Out of 14,707 patients treated from 1997 till May 2013, 6,350 patients from January to March 2011 were selected for the study from the routine clinical practice (mid-segment) to facilitate follow-up. They were categorized according to Clinical Etiologic Anatomic Pathophysiologic (CEAP) clinical classification system. Baseline data were accrued using a questionnaire. Patients were treated by microfoam sclerotherapy giving a maximum importance to smaller veins, depicting a modified technique of microfoam sclerotherapy (MMFST). This is based on the significance of microscopic venous valves (MVVs) in the development of chronic venous disease (CVD). Follow-up was according to a predefined schedule, and improvements and complications were recorded. A positive family history of VVs was reported in 85.23 % of patients. Half the study population belonged to CEAP clinical class IV. There were no significant complications in patients throughout the 2 to 6 years of follow-up. Recurrence was rarely reported during follow-up and was corrected by repeating the procedure as required during follow-up. MMFST is an innovation in the treatment of VVs based on new principles, with the potential to control and revert the symptoms of CVD, with minimal complications.
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Bioassay-guided isolation of methanolic extract of the leaves of Origanum vulgare Linn., yielded two protocatechuic acid ester derivatives, origanol A (1) and origanol B (2) along with ursolic acid (3), oleanolic acid (4), ß-sitosterol (5), and triacontanol (6). Structures of the compound were established based on physical and spectral data (UV, IR, (1)H and (13)C NMR and mass). Origanol A (1) showed significant mushroom tyrosinase inhibition activity.
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Papillary tumors of the pineal region are recently described as rare mass lesions with limited literature available on their natural history and imaging features. Magnetic resonance imaging (MRI) including perfusion, diffusion, and spectroscopic features were described in an 18-year-old girl with papillary tumor of pineal region. A well-defined, T1 hyperintense and contrast-enhancing mass lesion was noted in pineal region with few cystic spaces within. Solid portion of lesion showed minimal diffusion restriction with average apparent diffusion coefficient of 0.812 Χ 10 -3 mm 2 /s; on MR spectroscopy elevated myo-inositol peak with reduced N-acetylaspartate and elevated choline in the tumor. On perfusion study there was significantly high relative cerebral blood volume (rCBV) (6-9 times) and relative cerebral blood flow (rCBF). Our findings agree with previous descriptions of cystic areas with T1 hyperintense appearance of this tumor but very high level of tumor perfusion, diffusion restriction, and presence of myo-inositol peak are important imaging findings and may correlate with the recent reports of high tumor recurrence in these cases.
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Neoplasias Encefálicas/diagnóstico , Carcinoma Papilar/diagnóstico , Diagnóstico por Imagem/métodos , Glândula Pineal , Pinealoma/diagnóstico , Adolescente , Ácido Aspártico/análogos & derivados , Neoplasias Encefálicas/metabolismo , Carcinoma Papilar/metabolismo , Circulação Cerebrovascular , Colina , Feminino , Humanos , Glândula Pineal/diagnóstico por imagem , Glândula Pineal/patologia , Pinealoma/metabolismo , Radiografia , CintilografiaRESUMO
The present study demonstrates hexavalent chromium reduction and trivalent chromium tolerance behavior of marine Bacillus sp., MTCC 5514 through its extracellular enzyme reductase and biosurfactants production. The isolate reduces 10-2000 mg/L of hexavalent chromium to trivalent chromium with in 24-96 h respectively and the release of extracellular chromium reductase, found responsible for the reduction. Upon reduction, the concentration of trivalent chromium in the medium found comparatively less. Experimental results reveal, biosurfactants activity found responsible for the less concentration of Cr(III). Hypothetically, trivalent chromium upon formation get entrapped in the micelle of biosurfactants, prevents microbial cells from exposure towards trivalent chromium. Thus, the chosen isolate exhibit tolerance and growth with the increasing concentration of chromium.
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Bactérias/enzimologia , Espaço Extracelular/enzimologia , Metais Pesados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Água do Mar/microbiologia , Tensoativos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Cromo/metabolismo , Espaço Extracelular/efeitos dos fármacos , Oxirredução/efeitos dos fármacosRESUMO
The present study demonstrates in situ formation of multilamellar stable vesicles (MLSVs) of fatty acids released during the growth of microorganisms in the presence of triglycerides. Release of lipase during initial phase of growth hydrolyzes the triglycerides and release free fatty acids (mono or diglycerides) and glycerol. By extending the growth and the prevailing composition of media (unspent nutrients, salts, pH of the medium, biosurfactants, fatty acids, glycerol) and agitation transforms free fatty acids to MLSV of both cylindrical and spherical macroscopic structures via micelle formation with in 240h of incubation. Cross-sectional view and SEM analysis of macroscopic structures reveal the existence of continuous multilayering. Thermo-gravimetric analysis illustrates the stability of the vesicles. FT-IR analysis emphasizes the presence of amide linkages, responsible for self-assembly processes. Schematic representation of formation of MLSV demonstrated for further understanding. Additional exploration on MLSV formation in arteries and the relationship between MLSV and in situ plaque formation by the components of blood in the arteries are schematically explained and submitted as supporting information (SI-2).
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Bacillus/química , Ácidos Graxos não Esterificados/química , Tensoativos/química , Triglicerídeos/química , Bacillus/metabolismo , Bacillus/ultraestrutura , Proteínas de Bactérias/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Lipase/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Lipossomos/ultraestrutura , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/metabolismo , Termogravimetria , Triglicerídeos/metabolismoRESUMO
The present study demonstrates biopolymer production by in situ bio-based dimerization of fatty acids by microorganism isolated from marine sediments. Microbial isolate grown in Zobell medium in the presence of triglycerides for the period of 24-240 h at 37 degrees C, hydrolyze the applied triglycerides and sequentially dimerized the hydrolyzed products and subsequently polymerized and transformed to a biopolymer having appreciable adhesive properties. Physical (nature, odour, stickyness and tensile strength), chemical (instrumentation) and biochemical (cell free broth) methods of analyses carried out provided the hypotheses involved in the formation of the product as well as the nature of the product formed. Results revealed, lipolytic enzymes released during initial period of growth and the biosurfactant production during later period, respectively, hydrolyze the applied triglycerides and initiate the dimerization and further accelerated when the incubation period extended. The existence and the non-existence of in situ hydrolysis of various triglycerides followed by dimerization and polymerization and the mechanism of transformation of triglycerides to biopolymer are discussed in detail.
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Biopolímeros/química , Biopolímeros/metabolismo , Ácidos Graxos/metabolismo , Sedimentos Geológicos/microbiologia , Tensoativos/química , Tensoativos/metabolismo , Triglicerídeos/metabolismo , Dimerização , Ácidos Graxos/química , Hidrólise , Resistência à Tração , Triglicerídeos/química , ViscosidadeRESUMO
BACKGROUND: The role of palliative surgical resection in patients presenting with locally advanced or metastatic colorectal cancer (CRC) is unclear. Resection is often limited to symptomatic management of bleeding, obstruction, perforation or for relief of pain, in patients with an adequate performance status and an expected life span of over several weeks. An exploratory analysis to evaluate the influence of a palliative surgical resection on survival outcome in patients with advanced CRC is reported. METHOD: A retrospective review of medical records of all patients diagnosed with advanced CRC at our institution between the years 1998 and 2003 was undertaken. Tumour registry data were reviewed to identify age, gender, modalities of therapy [i.e. surgery (S), chemotherapy (C), radiation] and overall survival. IRB approval was obtained for this study. RESULTS: One hundred and eighty-five patients were identified. Median age was 67 years (range 30-99). M:F ratio was 1:1. Sixty-two per cent of patients (115/185) underwent a palliative surgical intervention. Median survival of patients who underwent S and those that did not undergo S was 22 and 3 months respectively (P < 0.0001). Forty-eight per cent of patients (79/184) underwent systemic C. Median survival of patients who received C + S, and patients who received C alone was 30 and 15 months respectively (P < 0.0004). Fifty-one per cent of patients who underwent S, received C; 30% of patients who did not undergo S, received C. Chemotherapy data were available on 46 of 79 patients. Patients treated with S + C, and C without S, received a median of 9 and 6 months of therapy respectively. The median number of regimens used were similar in both. CONCLUSION: These exploratory data suggest a positive influence of a palliative resection performed during the disease course of patients with advanced CRC. The increased frequency of utilization and the more prolonged duration of C in the surgically treated patients may in part contribute to this improved survival. This may also be reflective of performance status at the time of diagnosis. Future trials enrolling patients with advanced CRC should prospectively stratify for surgical intervention to further clarify the influence of this modality on the outcome of systemic therapy in this disease.