In vitro inhibitory effects of plant-based foods and their combinations on intestinal ¿-glucosidase and pancreatic ¿-amylase

ABSTRACT: BACKGROUND: Plant-based foods have been used in traditional health systems to treat diabetes mellitus. The successful prevention of the onset of diabetes consists in controlling postprandial hyperglycemia by the inhibition of alpha-glucosidase and pancreatic alpha-amylase activities, resulting in aggressive delay of carbohydrate digestion to absorbable monosaccharide. In this study, five plant-based foods were investigated for intestinal alpha-glucosidase and pancreatic alpha-amylase. The combined inhibitory effects of plant-based foods were also evaluated. Preliminary phytochemical analysis of plant-based foods was performed in order to determine the total phenolic and flavonoid content. METHODS: The dried plants of Hibiscus sabdariffa (Roselle), Chrysanthemum indicum (chrysanthemum), Morus alba (mulberry), Aegle marmelos (bael), and Clitoria ternatea (butterfly pea) were extracted with distilled water and dried using spray drying process. The dried extracts were determined for the total phenolic and flavonoid content by using Folin-Ciocateu's reagent and AlCl3 assay, respectively. The dried extract of plant-based food was further quantified with respect to intestinal alpha-glucosidase (maltase and sucrase) inhibition and pancreatic alpha-amylase inhibition by glucose oxidase method and dinitrosalicylic (DNS) reagent, respectively. RESULTS: The phytochemical analysis revealed that the total phenolic content of the dried extracts were in the range of 460.0-230.3 mg gallic acid equivalent/ g dried extract. The dried extracts contained flavonoid in the range of 50.3-114.8 mg quercetin equivalent/g dried extract. It was noted that the IC50 values of chrysanthemum, mulberry and butterfly pea extracts were 4.24+/-0.12 mg/ml, 0.59+/-0.06 mg/ml, and 3.15+/-0.19 mg/ml, respectively. In addition, the IC50 values of chrysanthemum, mulberry and butterfly pea extracts against intestinal sucrase were 3.85+/-0.41 mg/ml, 0.94+/-0.11 mg/ml, and 4.41+/-0.15 mg/ml, respectively. Furthermore, the IC50 values of roselle and butterfly pea extracts against pancreatic alpha-amylase occurred at concentration of 3.52+/-0.15 mg/ml and 4.05+/-0.32 mg/ml, respectively. Combining roselle, chrysanthemum, and butterfly pea extracts with mulberry extract showed additive interaction on intestinal maltase inhibition. The results also demonstrated that the combination of chrysanthemum, mulberry, or bael extracts together with roselle extract produced synergistic inhibition, whereas roselle extract showed additive inhibition when combined with butterfly pea extract against pancreatic alpha-amylase. CONCLUSIONS: The present study presents data from five plant-based foods evaluating the intestinal alpha-glucosidase and pancreatic alpha-amylase inhibitory activities and their additive and synergistic interactions. These results could be useful for developing functional foods by combination of plant-based foods for treatment and prevention of diabetes mellitus.     

CD4+ T-cell immunity to the Burkholderia pseudomallei ABC transporter LolC in melioidosis

Burkholderia pseudomallei causes melioidosis, a disease with a wide range of possible outcomes, from seroconversion and dormancy to sepsis and death. This spectrum of host-pathogen interactions poses challenging questions about the heterogeneity in immunity to B. pseudomallei. Models show protection to be dependent on CD4(+) cells and IFN-γ, but little is known about specific target antigens. Having previously implicated the ABC transporter, LolC, in protective immunity, we here use epitope prediction, HLA-binding studies, HLA-transgenic models and studies of T cells from seropositive individuals to characterize HLA-restricted LolC responses. Immunized mice showed long-lasting memory to the protein, whereas predictive algorithms identified epitopes within LolC that subsequently demonstrated strong HLA class II binding. Immunization of HLA-DR transgenics with LolC stimulated T-cell responses to four of these epitopes. Furthermore, the responsiveness of HLA transgenics to LolC revealed a hierarchy supportive of HLA polymorphism-determined differential susceptibility. Seropositive human donors of diverse HLA class II types showed T-cell responses to LolC epitopes, which are conserved among Burkholderia species including Burkholderia cenocepacia, associated with life-threatening cepacia complex in cystic fibrosis patients and Burkholderia mallei, which causes glanders. These findings suggest a role for LolC epitopes in multiepitope vaccine design for melioidosis and related diseases.     

Dynamic ultrasound with postural change facilitated the detection of an incisional hernia in a case with negative MRI findings

Incisional hernias commonly develop after abdominal surgeries with a lower incidence in patients receiving laparoscopy. Diagnosis through a non-surgical approach is usually made by computed tomography or magnetic resonance images (MRI) but both image modalities require patients to be examined in a supine position. We reported a case noticing a mass over her right lower abdomen after a laparoscopic liver segmentectomy with negative findings of hernia on MRI. A hernia sac was found by ultrasound with the patient being standing, highlighting the utility of dynamic ultrasound with postural change in investigation of incisional hernias.     

Synergistic effect of vancomycin combined with cefotaxime,imipenem, or meropenem against Staphylococcus aureus with reduced susceptibility to vancomycin

Background/aim We investigated the synergistic effect between vancomycin and β-lactams against vancomycin-susceptible (VSSA) and nonsusceptible MRSA isolates [heterogeneous vancomycin-intermediate S. aureus (hVISA) and VISA].Materials and methods A total of 29 MRSA, including 6 VISA, 14 hVISA, and 9 VSSA isolates, were subjected to a microbroth dilution-minimum inhibitory concentration (MIC) checkerboard using vancomycin combined with cefotaxime, imipenem, or meropenem. To confirm synergistic activity, the representative strains of VISA, hVISA, and VSSA were then selected for the time-kill curve method.Results The combination of vancomycin with imipenem, meropenem, or cefotaxime exhibited synergistic effects against 17 (2 VISA, 9 hVISA, and 6 VSSA), 14 (3 VISA, 9 hVISA and 2 VSSA), and 5 (3 VISA and 2 hVISA) isolates, respectively. Additive and indifferent effects were found in the remaining isolates, but no antagonistic effect was observed. Using time-kill assay, the vancomycin combined with either imipenem or cefotaxime demonstrated synergism against both VISA and hVISA isolates, while the synergistic effect with meropenem was obtained only in the VISA isolates.Conclusion This study demonstrated in vitro enhanced antibacterial activity of vancomycin plus β-lactams against clinical hVISA or VISA isolates. These combinations may be an alternative treatment for MRSA infections in clinical practice.     

Association between the expression of core 3 synthase and survival outcomes of patients with cholangiocarcinoma

Cholangiocarcinoma (CCA) is a highly aggressive and metastatic type of malignant carcinoma that is associated with high mortality rates and is difficult to detect at early stages. Core 3 structure is a mucin-type O-glycans synthesized by β1,3-N-acetylglucosaminyltransferase 6 (core 3 synthase), which plays an important role in the digestive system, in particular gastrointestinal goblet cells. It has been reported that core 3 synthase-expressing cells show lower migratory and invasive rates, and lower metastatic activity. A immunohistochemical study also showed that this enzyme was expressed in normal epithelial cells of the colon, but completely disappeared in colorectal cancer cells. The present study aimed to identify biomarkers that could be used to predict the prognosis of patients with CCA. Pathological specimens of 185 CCA tissues were immunohistochemically stained with two antibodies, G8-144 and MECA-79, which recognize core 3 synthase and 6-sulfated N-acetyllactosamine on the extended core-1 O-glycans, respectively. The association between G8-144 or MECA-79 positivity and patient prognosis was statistically analyzed. Positive expression of G8-144 was associated with improved prognosis in patients with distal CCA (dCCA). Patients with dCCA positive for G8-144 showed lower mortality rates than those with negative expression. However, the positive expression of MECA-79 was associated with CCA progression and metastasis, indicating that it is a poor prognostic marker for CCA. In conclusion, as both antibodies resulted in mirror-image staining, the involvement of G8-144 and MECA-79 in O-glycan synthesis could be considered as potential favorable and unfavorable biomarkers, respectively, for CCA prognosis.     

The Utility of Serum Tryptase in the Diagnosis of Food-Induced Anaphylaxis

Purpose

This study investigates the utility of serum tryptase for the confirmation of shrimp-induced anaphylaxis.

Methods

Patients with a history of shrimp allergy and positive skin prick tests (SPT) to commercial shrimp extract were recruited for shrimp challenges. Serum total tryptase was obtained at baseline and 60 min (peak) after the onset of symptoms.

Results

Thirty-nine patients were challenged. There were 12 patients with anaphylaxis, 20 with mild reactions and 7 without symptoms (control group). Characteristic features and baseline tryptase were not different among the 3 groups. The peak tryptase levels were higher than the baseline in anaphylaxis and mild reaction groups (P<0.05). The delta-tryptase (peak minus baseline) and the tryptase ratio (peak divided by baseline) in the anaphylaxis group were higher than the mild reaction and control groups (P<0.01). The optimum cut-off for peak tryptase to confirm anaphylaxis was 2.99 µg/L with 50% sensitivity, 85% specificity, 3.33 positive likelihood ratio (LR) and 0.59 negative LR. The manufacturer''s cut-off for peak tryptase was >11.4 µg/L with 17% sensitivity, 100% specificity, infinity positive LR and 0.83 negative LR. The best cut-off for delta-tryptase was ≥0.8 µg/L with 83% sensitivity, 93% specificity, 11.86 positive LR and 0.18 negative LR. The best cut-off for tryptase ratio was ≥1.5 with 92% sensitivity, 96% specificity, 23 positive LR and 0.08 negative LR.

Conclusions

The peak tryptase level should be compared with the baseline value to confirm anaphylaxis. The tryptase ratio provide the best sensitivity, specificity, positive and negative LR than a single peak serum tryptase for the confirmation of shrimp-induced anaphylaxis.     

Diabetes and cardiovascular risk factor controls in Thai type 2 diabetes with no history of cardiovascular complications; situation and compliance to diabetes management guideline in Thailand

BackgroundCardiovascular complication is one of the most important issues causing morbidity and death in diabetic patients. Primary prevention is a key to prevent this complication.AimsThe objective was to study the situations of diabetes and cardiovascular risk factor controls in Thai type 2 diabetic patients who had no history of cardiovascular complication at a university hospital in Thailand after the Thai diabetes management guideline was recently launched.MethodsThe study was a cross-sectional survey in type 2 diabetes patients with no history of cardiovascular disease. Seven hundred and fourteen patients were enrolled in the study and 54.3% were females. The data were collected retrospectively from out-patient medical records and an electronic data base for the patients who were followed up at the hospital during January–December 2010. The most recent laboratory values were utilized in the analysis.Results70%–90% of all patients were checked for HbA1c and lipid profiles (LDL-C, total cholesterol, triglycerides) at least once a year. It was observed that only 28% of the patients had HbA1c < 6.5%. Furthermore, the percentages of the patients who had blood pressure < 130/80 mmHg, and who had LDL-C < 100 mg/dL were 28% and 41%, respectively.ConclusionEven though the practice guideline has been launched since 2008, diabetes, hypertension and dyslipidemia were still poorly controlled. Further study is recommended to identify factors influencing these outcomes as well as the policy of diabetic care in Thailand is needed to be seriously implemented.     

Mycophenolic acid pharmacokinetics during maintenance immunosuppression in African American and Caucasian renal transplant recipients

Renal transplant recipients exhibit variability in mycophenolic acid (MPA) and MPA glucuronide (MPAG) pharmacokinetics, which are influenced by clinical and demographic factors. Racial influence on MPA and MPAG pharmacokinetics was investigated in 53 patients: 17 African American males, 22 Caucasian males, and 14 females receiving mycophenolate mofetil (MMF) and cyclosporine. A 12-hour steady-state pharmacokinetic study was conducted. Enterohepatic circulation of MPA was characterized by a second plasma concentration peak and was included in a novel statistical model with MPAG. MPA clearance in African American males was 26.5 ± 14.4 L/h versus 17.9 ± 6.1 L/h in Caucasian males (P = .035) and 16.1 ± 4.6 L/h in Caucasian females (P = .024) with no difference noted in MPA troughs. Enterohepatic circulation occurred less frequently in African American males (23%) compared with Caucasian males (42%) and Caucasian females (50%) (P > .05). Cyclosporine exposure was correlated with MPA and MPAG pharmacokinetics, whereas creatinine clearance influenced MPAG pharmacokinetics. A racial difference was noted with more rapid MPA clearance in African American males compared with Caucasians. The results support differential MPA dosing and the role of therapeutic drug monitoring in addition to considering the influence of renal function and concurrent immunosuppressives on MPA and MPAG pharmacokinetics.     

Effect of an empowerment-based nutrition promotion program on food consumption and serum lipid levels in hyperlipidemic Thai elderly

Abstract   This quasi-experimental study examined the effects of an empowerment-based nutrition promotion program on food consumption and serum lipid levels among hyperlipidemic Thai elderly. Fifty-six experimental subjects received the program; 48 control subjects maintained their habitual lifestyle. The statistical methods used were the t -test, Z -test, and χ²/Fisher's exact test. After the program, the consumption of high saturated fat, cholesterol, and simple sugar diets was significantly lower for the experimental group than for the control group. The percentage change of the serum total cholesterol of the experimental subjects was significantly higher than that of the control subjects. The number of experimental subjects that changed from hyperlipidemia to normolipidemia significantly increased compared to that for the control subjects. The implementation of this program was related to an improvement in food consumption and serum lipid levels among hyperlipidemic Thai elderly and, therefore, has implications for practice.