37 research outputs found
Time-kill profiles and cell-surface morphological effects of crude Polycephalomyces nipponicus Cod-MK1201 mycelial extract against antibiotic-sensitive and -resistant Staphylococcus aureus
Purpose: To examine the effect of crude Polycephalomyces nipponicus Cod-MK1201 mycelial extract on the viability and cell surface morphology of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA).Methods: Time-kill assays were conducted by incubating test bacteria with the extract and sampling at selected time points within a 24 h period. The effects of the extract on MSSA and MRSA ultrastructure were determined using a scanning electron microscope (SEM).Results: Time-kill assay data indicate a bactericidal effect against both strains of staphylococci. The extracts were rapidly bactericidal at concentrations of 1 x MIC and 2 x MIC, achieving complete elimination of the test bacterial strains within 2 h. SEM micrographs of S. aureus taken after treatment with various concentrations of the extract revealed extensive morphological alterations to the cell surface of both MSSA and MRSA.Conclusion: The results confirm the antibacterial activity of P. nipponicus Cod-MK1201 mycelial extract. Further research may allow this to be developed as an alternative therapy to alleviate S. aureus infection.Keywords: Antibacterial activity, Polycephalomyces nipponicus, Staphylococcus aureus, Time-kill assay, Cell surface morpholog
Effects of mycelial extract and crude protein of the medicinal mushroom, Ophiocordyceps sobolifera, on the pathogenic fungus, Candida albicans
Purpose: To investigate the antifungal effect of the mycelial extracts and crude proteins of the medicinal mushroom, Ophiocordyceps sobolifera on Candida albicans.Methods: The antifungal activities of the mycelial extracts and crude proteins of seven strains of the entomopathogenic fungus, Ophiocordyceps sobolifera, were screened against Candida albicans strain NCYC854 using an agar well diffusion method. Minimum inhibitory concentrations (MIC) and minimum fungicidal concentration (MFC) were determined using broth microdilution method. The kinetics of fungal death was elucidated via time-kill assays, and while ultrastructural alteration changes to fungal cells were investigated by scanning electron microscopy (SEM).Results: The antifungal activities of the mycelial extracts were superior to those of the crude proteins. Among the isolates, Cod-KK1643 exhibited the highest activity with the lowest MIC against the test strains. Therefore, it was chosen for further investigations. The isolate Cod-KK1643 exhibited concentration- and time-dependent fungistatic activity in the time kill assay. However, these activities were absent in the crude protein of the isolate. Moreover, Cod-KK1643 mycelial extract induced morphological alterations in fungal cells, such as decreased cell size, and crushed or cracked appearance. Slight alterations in cell morphology (decreased cell size or crushed appearance) were observed in the crude protein treatment.Conclusion: The mycelial extracts of the fungus, O. sobolifera (especially isolate Cod-KK1643) exert potent antifungal activity against human pathogenic fungus, C. albicans.Keywords: Anti-fungal activity, Candida albicans, Entomopathogenic fungus, Ophiocordyceps sobolifer
Microarray Method for the Rapid Detection of Glycosaminoglycan–Protein Interactions
Glycosaminoglycans (GAGs) perform numerous vital functions within the body. As major components of
the extracellular matrix, these polysaccharides participate in a diverse array of cell-signaling events. We have
developed a simple microarray assay for the evaluation of protein binding to various GAG subclasses. In a
single experiment, the binding to all members of the GAG family can be rapidly determined, giving insight
into the relative specificity of the interactions and the importance of specific sulfation motifs. The arrays
are facile to prepare from commercially available materials
Surgical Outcomes of Bariatric Surgery in Siriraj Hospital for the First 100 Morbidly Obese Patients Treated
Objective: Bariatric surgery is considered the most effective treatment for morbid obesity, and is increasingly performed in Thailand and globally. We aimed to establish the outcomes of bariatric surgery performed at Siriraj Hospital, Bangkok.
Materials and Methods: This was a retrospective study of patients who underwent bariatric surgery between January 2012 and June 2016.
Results: The records of the first 100 patients who underwent bariatric surgery were reviewed, comprising 58 patients who underwent laparoscopic sleeve gastrectomy (LSG) and 42 patients who underwent laparoscopic Roux-en-Y gastric bypass (LRYGB). The median patient age, preoperative body weight, and BMI were 36 years old, 129 kg, and 46.3 kg/m2. All the procedures were performed by a laparoscopic approach. The median operative times for LSG and LRYGB were 156 [85-435] and 265 [180-435] minutes. The median hospital stay was 3 days [3-14]. The major complication rate was 4%. There was no mortality in the 30-day postoperative period. The mean %excess weight loss (%EWL) of LSG was 56.8 ± 19.8%, 59.9 ± 21.7%, and 55.1 ± 21.3%, at 1, 2, and 3 years after surgery. The mean %EWL of LRYGB was 67 ± 18.3%, 66.2 ± 21.4%, and 63.6 ± 19.9%, at 1, 2, and 3 years after surgery. In the patients with type-II diabetes mellitus, 67% had complete diabetic remission at 1 year. The median FBS dropped from 127 to 99 mg/dL (p < 0.001) and HbA1c from 6.6% to 5.5% (p < 0.001). The remission rates of hypertension and dyslipidemia were 58% and 73%.
Conclusion: The bariatric procedures are safe with a low complication rate. The procedures also provide good outcomes in postoperative weight loss and comorbidity resolution
Changes in Physical Components after Gastrectomy for Adenocarcinoma of Stomach and Esophagogastric Junction
Objective: Enhanced Recovery After Surgery (ERAS) is a multidisciplinary approach that aims to optimize perioperative management, promote postoperative recovery, reduce postoperative complications, and improve long-term survival. The current study aimed to evaluate and compare the postoperative physical activity after gastrectomy between patients who underwent upper gastrointestinal surgery according to ERAS and those who underwent surgery based on the conventional care (CC) protocol.
Materials and Methods: This prospective and retrospective review enrolled 60 patients (n = 31, ERAS group; n = 29, CC protocol group) diagnosed with adenocarcinoma of the stomach and esophagogastric junction who underwent curative surgical resection. Physical outcomes, including body weight, body mass index, body fat percentage, basal metabolic rate, muscle mass, gait speed, and handgrip strength at the preoperative and immediate postoperative periods and at 1, 3, and 6 months postoperatively, were comparedbetween the ERAS and CC protocol groups.
Results: One month after surgery, the ERAS group had a lower percentage of body weight loss than the CC protocol group. There was no significant difference in terms of muscle mass loss between the two groups. The hand grip strength of the ERAS group increased after surgery. Further, at 1 month postoperatively, the gait speed of patients who underwent total gastrectomy in the ERAS group was significantly higher than that of patients in the CC protocol group.
Conclusion: ERAS for gastrectomy was associated with a lower percentage of weight loss and a trend toward physical activity enhancement in the early postoperative period
Paramyxovirus Fusion and Entry: Multiple Paths to a Common End
The paramyxovirus family contains many common human pathogenic viruses, including measles, mumps, the parainfluenza viruses, respiratory syncytial virus, human metapneumovirus, and the zoonotic henipaviruses, Hendra and Nipah. While the expression of a type 1 fusion protein and a type 2 attachment protein is common to all paramyxoviruses, there is considerable variation in viral attachment, the activation and triggering of the fusion protein, and the process of viral entry. In this review, we discuss recent advances in the understanding of paramyxovirus F protein-mediated membrane fusion, an essential process in viral infectivity. We also review the role of the other surface glycoproteins in receptor binding and viral entry, and the implications for viral infection. Throughout, we concentrate on the commonalities and differences in fusion triggering and viral entry among the members of the family. Finally, we highlight key unanswered questions and how further studies can identify novel targets for the development of therapeutic treatments against these human pathogens
Gastroduodenal intussusception of a gastrointestinal stromal tumor: a rare cause of acute pancreatitis
Patients with symptomatic gastrointestinal stromal tumor (GIST) typically present with gastrointestinal bleeding and abdominal pain. This report presents an unusual case of fundic GIST complicated by gastroduodenal intussusception, manifesting as acute pancreatitis. The patient presented with epigastric pain and pancreatic enzyme elevation; thus, he was diagnosed with acute pancreatitis. Computed tomography showed evidence of pancreatitis and a 4×4.7 cm well-defined hyperdense lesion in the 2nd part of the duodenum, compressing the pancreatic head and pancreatic duct. Esophagogastroduodenoscopy revealed invagination of the gastric folds into the duodenum, causing pyloric canal blockage consistent with gastroduodenal intussusception. Spontaneous reduction of the lesion during endoscopy revealed a 4 cm pedunculated subepithelial mass with central ulceration originating from the gastric fundus. Endoscopic ultrasound demonstrated a heterogeneous hypoechoic lesion originating from the 4th layer of the gastric wall. Laparoscopic-endoscopic intragastric wedge resection of the fundic lesion was subsequently performed, and surgical histology confirmed GIST
Diversity in Glycosaminoglycan Binding Amongst hMPV G Protein Lineages
We have previously shown that hMPV G protein (B2 lineage) interacts with cellular glycosaminoglycans (GAGs). In this study we examined subtypes A1, A2 and B1 for this interaction. GAG-dependent infectivity of available hMPV strains was demonstrated using GAG-deficient cells and heparin competition. We expressed the G protein ectodomains from all strains and analysed these by heparin affinity chromatography. In contrast to the B2 lineage, neither the A2 or B1 G proteins bound to heparin. Sequence analysis of these strains indicated that although there was some homology with the B2 heparin-binding domains, there were less positively charged residues, providing a likely explanation for the lack of binding. Although sequence analysis did not demonstrate well defined positively charged domains in G protein of the A1 strain, this protein was able to bind heparin, albeit with a lower affinity than G protein of the B2 strain. These results indicate diversity in GAG interactions between G proteins of different lineages and suggest that the GAG-dependency of all strains may be mediated by interaction with an alternative surface protein, most probably the conserved fusion (F) protein. Analysis of both native and recombinant F protein confirmed that F protein binds heparin, supporting this conclusion
Role of Cellular Glycosaminoglycans and Charged Regions of Viral G Protein in Human Metapneumovirus Infection▿
Human metapneumovirus (hMPV) is an important cause of lower respiratory tract disease, particularly in infants and young children. hMPV has two major glycoproteins, G and F, which are responsible for virus attachment and membrane fusion, respectively. We investigated the role of cellular glycosaminoglycans (GAGs) and G protein in hMPV infection. The pretreatment of hMPV with soluble heparin markedly inhibited the infection of HEp-2 cells. Recombinant G protein, comprising the extracellular domain of G, bound to heparin-agarose columns and also to HEp-2 cells. hMPV infection and G protein binding to HEp-2 cells was inhibited by other soluble GAGs, including chondroitin sulfates, by the enzymatic removal of cell surface GAGs with GAG lyases or by the pretreatment of cells with basic fibroblast growth factor. The role of cellular GAGs was confirmed by the binding of G protein to wild-type CHO cells but not to GAG-deficient CHO-pgsA745 cells. An analysis of the G protein sequence revealed two adjacent clusters of positively charged amino acids (149EKKKTRA155 and 159QRRGKGKE166). Truncated G fragments were expressed, and only the fragment containing these putative heparin binding domains retained heparin binding. The alanine mutagenesis of charged residues in either of these regions resulted in the loss of binding to heparin and to HEp-2 cells, suggesting that both sites are likely to be required for hMPV attachment. These results, taken together with the inhibition of hMPV infection by soluble G protein, indicate an important role for G protein and cellular GAGs in hMPV infection