Structural Characterization of Mannoglucan Isolated from Ophiocordyceps sobolifera and Its Antioxidant Activities.

A novel polysaccharide structure (PS-T80) was collected from Ophiocordyceps sobolifera biomass and characterized via a combination of chemical and spectral analyses. Employing high-performance gel permeation chromatography (HPGPC), the average molecular weight is proven to be 7.4 × 104 Da. Furthermore, a sugar composition analysis of the obtained polysaccharide suggests two main sugars, ß-d-glucose and α-d-mannose, at a molar ratio of 2:1, respectively, in the backbone. The structure analysis unveils that PS-T80 is a mannoglucan, possessing the repeating unit of [→3)-ß-d-Glcp-(1 → 3)-α-d-Manp-(1 → 3)-ß-d-Glcp-(1→] n . Such a configuration could be considered a novel polysaccharide. Impressively, in vitro antioxidant tests revealed that PS-T80 has a promising antioxidant activity. These results demonstrate that the obtained PS is a potential bioactive material for biomedical applications.

Rich d-Fructose-Containing Polysaccharide Isolated from Myxopyrum smilacifolium Roots toward a Superior Antioxidant Biomaterial.

The presented study attempts to unveil and evaluate the antioxidant activity of a novel heteropolysaccharide separated from the roots of Myxopyrum smilacifolium (denoted as PS-MSR). The molecular weight of PS-MSR is found to be 1.88 × 104 Da and contains two principal sugars, which are d-glucose and d-fructose, in the backbone. Decoding the structure of the obtained PS-MSR sample has disclosed a novel polysaccharide for the first time. Indeed, the PS-MSR is composed of (1 → 3)-linked glucosyl units and (2 → 3)-linked fructosyl units. In addition, the 1D and 2D NMR spectra of the PS-MSR sample display the repeating unit of the isolated polysaccharide, [→3)-α-d-Glcp-(1 → 3)-ß-d-Frucf-(2 → 3)-ß-d-Frucf-2 → 3)-)-ß-d-Frucf-ß-(2→] n . Interestingly, the PS-MSR sample exhibits outstanding antioxidant activity, signifying the potential utilization of the explored polysaccharide for antioxidant-based material.

Antimicrobial susceptibility of Burkholderia pseudomallei isolates in Northern Vietnam.

OBJECTIVES: The antimicrobial susceptibility pattern of clinical Burkholderia pseudomallei (B. pseudomallei) in Vietnam has not been reported since the first publication in 2008. The present study aimed to determine the antimicrobial susceptibility pattern of B. pseudomallei isolated in a tertiary referral centre in Hanoi from January 2012 to December 2017. METHODS: A total of 312 B. pseudomallei isolates obtained from melioidosis patients admitted to a 2000-bed general hospital were analysed by the Etest method. Interpretation of the susceptibility testing results were reported using Clinical and Laboratory Standards Institute guidelines. RESULTS: All isolates were susceptible to ceftazidime, imipenem and amoxicillin-clavulanate (100%) with MIC90s relatively low (2µg/mL). Two isolates had intermediate resistance to doxycycline (0.6%) and 34 isolates were resistant to trimethoprim/sulfamethoxazole (10.9%). CONCLUSION: The results of this study suggest that currently recommended antibiotics for melioidosis treatment can be empirically used, but continuously monitoring antimicrobial susceptibility should be a concern.

The Dlx5-FGF10 signaling cascade controls cranial neural crest and myoblast interaction during oropharyngeal patterning and development.

Craniofacial development depends on cell-cell interactions, coordinated cellular movement and differentiation under the control of regulatory gene networks, which include the distal-less (Dlx) gene family. However, the functional significance of Dlx5 in patterning the oropharyngeal region has remained unknown. Here, we show that loss of Dlx5 leads to a shortened soft palate and an absence of the levator veli palatini, palatopharyngeus and palatoglossus muscles that are derived from the 4th pharyngeal arch (PA); however, the tensor veli palatini, derived from the 1st PA, is unaffected. Dlx5-positive cranial neural crest (CNC) cells are in direct contact with myoblasts derived from the pharyngeal mesoderm, and Dlx5 disruption leads to altered proliferation and apoptosis of CNC and muscle progenitor cells. Moreover, the FGF10 pathway is downregulated in Dlx5-/- mice, and activation of FGF10 signaling rescues CNC cell proliferation and myogenic differentiation in these mutant mice. Collectively, our results indicate that Dlx5 plays crucial roles in the patterning of the oropharyngeal region and development of muscles derived from the 4th PA mesoderm in the soft palate, likely via interactions between CNC-derived and myogenic progenitor cells.

Heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a growing complication of a common medication used to prevent deep vein thrombosis (DVT) in hospitalized patients. The purpose of this article is to review the mechanism that causes paradoxical thrombus formation in HIT and ways to recognize this important complication with various testing modalities and to discuss the approaches to treatment once a diagnosis has been made. HIT is a clinical diagnosis that can be further supported by utilizing the "4 Ts": thrombocytopenia, timing of platelet count fall, thrombosis or other complications, and other causes for thrombocytopenia. Diagnosis of HIT can be established using an HIT antibody test. Once a drop in platelet count is observed in a patient, it is important to rule out HIT. When HIT is first suspected, it is important to discontinue all heparin products. The gold standard in diagnosing HIT is the 14C-serotonin release assay (14C-SRA) assay, which has high sensitivity and specificity but is technically demanding and more time consuming than other antibody-detecting immunoassays. Anticoagulation in HIT patients is essential due to the increased risk of thrombosis. Treatment consists of utilizing alternative, nonheparin anticoagulants like lepirudin, argatroban, bivalirudin, or fondaparinux (although fondaparinux is not formally approved by the US Food and Drug Administration for this condition). Each of these agents should be individually formulated based on the patient and the presence/absence of liver or renal failure. Treatment duration has yet to be determined. However, in patients requiring long-term anticoagulation (pulmonary embolism, DVT, stroke), the transition to warfarin can be made once the platelet count recovers and there has been at least 5 days of overlap with a nonheparin anticoagulant.

Improving frontline treatment for chronic myeloid leukemia: emerging evidence for use of nilotinib and dasatinib.

The approval of imatinib in 2001 changed the landscape of chronic myeloid leukemia (CML) management, becoming the standard of care and improving the survival rates of patients. With the prevalent use of imatinib worldwide, it was observed that up to one-third of patients are resistant to or intolerant of imatinib therapy, fueling the search for safer and more effective agents. The newer and more potent tyrosine kinase inhibitors nilotinib and dasatinib were first indicated for the treatment of imatinib-resistant/-intolerant patients, for whom these agents are both safe and efficacious. More recent clinical studies have examined nilotinib and dasatinib in the frontline setting in newly diagnosed patients. Data reported from the phase III ENESTnd (Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients) study and the DASISION (Dasatinib versus Imatinib in Patients with Newly Diagnosed Chronic-phase CML) trial support the use of nilotinib and dasatinib as potential new standards for frontline care of newly diagnosed patients with CML in chronic phase. Furthermore, both agents have received regulatory approval for use as frontline agents. These agents have demonstrated significantly superior efficacy compared with imatinib, as measured by complete cytogenetic response and major molecular response rates. In addition, progression to advanced disease was significantly lower for nilotinib, and a trend toward lower progression was observed with dasatinib. Although both nilotinib and dasatinib are generally well tolerated in the frontline setting, they have different safety profiles that may affect their selection as treatment. Understanding the efficacy, safety profiles, and patterns of resistance to various BCR-ABL1 mutations of these newer agents, as well as implementing management strategies to treat adverse events, will help physicians to provide the best therapy options for their patients with CML.

An unusual presentation of Burkitt lymphoma.

We describe a 37-year-old non-smoker who presented with dyspnea and a unilateral effusion secondary to Burkitt lymphoma (BL). The diagnosis was made by pleural tissue biopsy using video-assisted thoracoscopic surgery (VATS). Burkitt lymphoma is discussed.