Immobilization of amyloglucosidase onto macroporous cryogels for continuous glucose production from starch

Poly(methyl methacrylate-glycidyl methacrylate) [Poly(MMA-GMA)] cryogels were synthesized using monomers of methylmethacrylic acid and epoxy group bearing GMA via radical cryopolymerization technique. Synthesized cryogels were used for the immobilization of amyloglucosidase to the cryogel surface using epoxy chemistry. Characterizations of the free and immobilized amyloglucosidase were carried out by comparing the optimum and kinetic parameters of enzymes. For this, pH and temperature profiles of free and immobilized preparation were studied and, it was found that, optimum pH of enzyme was not change upon immobilization (pH 5.0), while optimum temperature of the enzyme shifted 10 °C to warmer region after immobilization (optimum temperatures for free and immobilized enzyme were 55 and 65 °C, respectively). Kinetic parameters of free and immobilized enzyme were also investigated and K_m values of free and immobilized amyloglucosidase were found to be 2.743 and 0.865 mg/mL, respectively. V_max of immobilized amyloglucosidase was found to be (0.496 µmol/min) about four times less than that of free enzyme (2.020 µmol/min). Storage and operational stabilities of immobilized amyloglucosidase were also studied and it was showed that immobilized preparation had much more stability than free preparation. In the present work, amyloglucosidase immobilized poly(MMA-GMA) cryogels were used for continuous glucose syrup production from starch for the first time. Efficiency of immobilized enzyme was investigated and released amount of glucose was found to be 2.54 mg/mL at the end of the 5 min of hydrolysis. The results indicate that the epoxy functionalized cryogels offer a good alternative for amyloglucosidase immobilization applications with increased operational and thermal stability, and reusability. Also, these cryogels can be used for immobilization of other industrially valuable enzymes beyond amyloglucosidase.     

The Role of Serum Procalcitonin Levels in Predicting Ascitic Fluid Infection in Hospitalized Cirrhotic and Non-cirrhotic Patients

Objective: To determine the role of serum procalcitonin levels in predicting ascites infection in hospitalized cirrhotic and non-cirrhotic patients.Methods: A total of 101 patients (mean age: 63.4±1.3, 66.3% were males) hospitalized due to cirrhosis (n=88) or malignancy related (n=13) ascites were included in this study. Spontaneous bacterial peritonitis (SBP, 19.8%), culture-negative SBP (38.6%), bacterascites (4.9%), sterile ascites (23.8%) and malign ascites (12.9%) groups were compared in terms of procalcitonin levels in predicting ascites infection. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic performance of procalcitonin levels and predicting outcome of procalcitonin levels was compared with C-reactive protein (CRP).Results: Culture positivity was determined in 26.7% of overall population. Serum procalcitonin levels were determined to be significantly higher in patients with positive bacterial culture in ascitic fluid compared to patients without culture positivity (median (min-max): 4.1 (0.2-36.4) vs. 0.4 (0.04-15.8), p<0.001). Using ROC analysis, a serum procalcitonin level of <0.61 ng/mL in SBP (area under curve (AUC): 0.981, CI 95%: 0.000-1.000, p<0.001), <0.225 ng/mL in culture-negative SBP (AUC: 0.743, CI 95%: 0.619-0.867, p<0.001), <0.42 ng/mL in SBP and culture-negative SBP patients (AUC: 0.824, CI 95%: 0.732-0.916, p<0.001), and <1.12 ng/mL in bacterascites (AUC: 0.837, CI 95%: 0.000-1.000, p=0.019) were determined to accurately rule out the diagnosis of bacterial peritonitis. Predictive power of serum procalcitonin levels in SBP + culture-negative SBP group (AUCs: 0.824 vs 0.622, p=0.004, Fig 4), culture-positive SBP (AUCs: 0.981 vs 0.777, p=0.006, Fig 5) and (although less powerfull) in culture-negative SBP (AUCs: 0.743 vs 0.543, p=0.02, Fig 6) were found significantly higher than CRP.Conclusion: According to our findings determination of serum procalcitonin levels seems to provide satisfactory diagnostic accuracy in differentiating bacterial infections in hospitalized patients with liver cirrhosis related ascites.     

Enzymatic Debridement in Necrotizing Pancreatitis

Multiple organ failure and pancreatic necrosis are the factors that determine prognosis in acute pancreatitis attacks. We investigated the effects of collagenase on the debridement of experimental pancreatic necrosis. The study covered 4 groups; each group had 10 rats. Group I was the necrotizing pancreatitis group. Group II was the collagenase group with pancreatic loge by isotonic irrigation following necrotizing pancreatitis. Group III was the collagenase group with pancreatic loge following necrotizing pancreatitis. Group IV was the intraperitoneal collagenase group following necrotizing pancreatitis. The progress of the groups was compared hematologically and histopathologically. There was no difference among the groups regarding the levels of leukocyte, hemogram, and urea. The differences in AST levels between Group I and II; and differences in glucose, calcium, LDH, AST, and amylase between Group II and III; between Group II and IV; between Group I and III; and between Group I and IV were statistically significant (P < 0.05). There were statistically significant differences between Group II and III, and Group II and IV regarding edema, acinar necrosis, inflammatory cell infiltration, hemorrhage, and fat necrosis (P < 0.05). In conclusion, the collagenase preparation used in this experimental pancreatitis model was found to be effective in the debridement of pancreatic necrosis.Key words: Acute pancreatitis, Necrose, Collagenase, DebridementAcute pancreatitis (AP) is a nonbacterial inflammatory disease of the pancreas that can range from interstitial edema to pancreatic necrosis in its severest form. In about 20% of AP attacks necrosis can develop in the pancreas while the disease limits itself and regresses in a couple of days in many patients (80%).¹The definitions that are still widely in effect today regarding the classification of acute pancreatitis were determined in 1992 at the Atlanta Conference.² The conference aimed at achieving a common classification for AP and its complications. Within severe acute pancreatitis, of which necrotizing pancreatitis is a part, organ failure and local complications can be seen (necrosis, pseudocyst, and abscess). Multiple organ failure and pancreatic necrosis are the factors that determine the prognosis. Half of the mortalities are observed within a period of 1 or 2 weeks. Necrotizing pancreatitis makes up for the 10–20% of AP cases. Severe pancreatitis has a high mortality rate and functional diseases like diabetes are seen in one-third to one-fifth of the recovered patients.³While the mortality rates are about 10% in the presence of sterile pancreatic necrosis, they go up over 30% in the existence of infected necrosis.¹ Regarding acute necrotizing pancreatitis, there is still no consensus on surgical indications and the time of surgical intervention, the surgical method to be used, and which patients need conservative treatment and which ones need surgical treatment. The goal in the surgical treatment of acute necrotizing pancreatitis is to isolate the necrotic tissue that might cause sepsis and multiple organ failure and to reduce the risk of mortality. The timing of necrosectomy as well as the way in which necrosectomy is performed is significant in necrotizing pancreatitis. The issue of the possibility that necrosectomy can be performed through minimally-invasive interventions instead of open surgery is still being discussed.³We planned to investigate the activity of collagenase clostridiopeptidase A (EC 3.424.3), which has never been attempted before in the debridement of experimental pancreatic necrosis (but which has been used for enzymatic debridement), and the enzyme preparation containing the accompanying proteases (Sterile Novuxol^®, Abbott, Uetersen, Germany). We aimed to evaluate the response of the disease to treatment through laboratory and histopathologic data, by using the enzyme preparation to treat necrotizing pancreatitis.     

Bone mineral density evaluation of patients with type 2 diabetes mellitus

[Purpose] Diabetes mellitus is a metabolic disorder resulting from a defect in insulin secretion, insulin action, or both. A consequence of this is chronic hyperglycemia with disturbances in carbohydrate, fat and protein metabolism. We investigated whether there is any difference among DM patients and a control group in terms of lumbar and femur BMD (bone mineral density), and standard deviation scores (Z score and T score). [Subjects and Methods] This randomized, prospective, controlled, single-blind study was conducted in the Physical Medicine and Rehabilitation Department Faculty of Medicine, Bezm-i Alem Vakıf University. Patients with type 2 diabetes mellitus were included in the patient groups. Healthy individuals were included in the control group. [Results] A total of 126 patients completed the study (63 in the study group, 63 in the control group). There was no significant difference in the results of the laboratory examinations of the cases. The bone mineral densities of the cases were found to be significantly low in terms of the lumbar (L1–4) T scores in the type 2 diabetes group. [Conclusion] Although osteoporosis is one of the potential complications of type 1 diabetes, its effect on bone mineral density in type 2 DM is controversial. In different studies, the bone mineral density values have increased, decreased or remained normal. With the exception of the lumbar (L1–4) T score, similar results were obtained in this study.Key words: Type 2 diabetes mellitus, Osteoporosis, Bone mineral density     

Predictors of Treatment Outcomes in ANCA-Associated Vasculitis with Severe Kidney Failure

Background and objectives

In ANCA-associated GN, severe renal dysfunction portends a poor prognosis for renal recovery and patient survival. This study evaluated the prognostic factors affecting renal and patient outcomes in patients presenting with severe kidney failure to guide immunosuppressive therapy.

Design, setting, participants, & measurements

This study retrospectively evaluated clinical and histopathologic characteristics of 155 patients who underwent biopsy between October 1985 and February 2011 (median eGFR at presentation, 7.1 ml/min per 1.73 m²; 87% required hemodialysis), all treated with immunosuppressive medications. Three outcomes of interest were measured: patient survival, renal survival, and treatment response (defined as dialysis-free survival without active vasculitis by 4 months after biopsy). Competing risk, Cox, and logistic regression analyses were conducted for each outcome measure.

Results

Within 4 months after biopsy, treatment response was attained in 51% of patients, 35% remained on dialysis, and 14% died. In a competing risk analysis, estimated cumulative incidence rates of ESRD and disease-related mortality were 26% and 17% at 1 year and 32% and 28% at 5 years, respectively. Cyclophosphamide therapy and treatment response by 4 months were independently associated with patient and renal survival, adjusting for the percentage of normal glomeruli, histopathologic chronicity index score, and baseline clinical characteristics. Only 5% of patients still dialysis dependent at 4 months subsequently recovered renal function. Low chronicity index score (odds ratio [OR], 1.16; 95% confidence interval [95% CI], 1.04 to 1.30, per unit decrease) and baseline eGFR>10 ml/min per 1.73 m² (OR, 2.77; 95% CI, 1.09 to 7.01) were significantly associated with treatment response by 4 months. Among cyclophosphamide-treated patients, the likelihood of treatment response was >14% even with highest chronicity index score and eGFR<10 ml/min per 1.73 m².

Conclusions

Although low baseline renal function and severe renal scarring are associated with lower treatment response rate, no “futility” threshold could be identified. Conversely, continued immunosuppressive therapy beyond 4 months is unlikely to benefit patients who remain dialysis dependent.     

The foot in systemic disease: management of the patient with rheumatoid arthritis or diabetes mellitus

The foot is commonly affected in systemic diseases such as rheumatoid arthritis and diabetes mellitus. Treating patients who suffer with foot pathology secondary to systemic diseases requires a multidisciplinary approach, following the principles outlined within this review. There is little high level evidence in this field, such as prospective controlled clinical trials, hence much of what we know and practise is based upon the expert opinion of key individuals in specialist centres, to whom we owe a great debt.     

Safety and efficiency of interventional pulmonologists performing percutaneous tracheostomy

Background: The steady rise in the number of critically ill patients in the USA has led to an increase in the need for tracheostomies in patients requiring chronic ventilatory support. There is a matched need for experienced operators to safely and efficiently perform these procedures. Objectives: We evaluated the effects on procedural outcomes and efficiency of percutaneous dilatational tracheostomy (PDT) placement in the medical intensive care unit (MICU) by the surgical team (ST) or interventional pulmonologists (IP). The IP team joined the PDT team in September 2007 and became primarily responsible for all PDT in the MICU. Methods: A retrospective analysis of prospectively collected data of patients who received PDT in the MICU by ST and IP from September 2007 to August 2010 was made. Outcomes including safety, efficacy, and procedural efficiency were compared. Results: One hundred seven patients underwent bedside PDT in the MICU during this period. Forty-three procedures (40.2%) were performed by the ST and 64 procedures (59.8%) were performed by IP. There was no statistical difference between the incidence of airway injury and infection between the two procedural groups. There were no deaths related to the performance of PDT in our series. PDT was completed within 48 h of request in 100% of IP patients and 95% of ST patients (p = 0.08). Conclusions: There were no statistical differences in PDT between the ST and IP groups when comparing complications. There was a trend towards an increased efficiency in time to PDT after consultation within the IP PDT group. Trained IP can safely and effectively perform PDT.     

Effect of sex steroids on soleus muscle response in hypocalcemic medium (in vitro)

Purpose

Postoperative hypocalcemia is a frequently encountered complication of thyroid surgery. Since hypocalcemic symptoms are closely associated with sex, the aim of this study is to investigate the effects of sex steroids on muscle tissue under hypocalcemic conditions.

Methods

Six groups consisting of control male (M), control female (F), gonadectomized male (M−), gonadectomized female (F−), estradiol-applied gonadectomized male (MX), and testosterone-applied gonadectomized female (FX) rats were used. Contraction recordings were obtained from soleus muscle flaps. Maximal tension (PT), frequency required for 50% of PT (F50), contraction velocity at F50 (V50), and changes in contraction values (d[PT], d[F50], d[V50]) between normocalcemic and hypocalcemic conditions were calculated.

Results

d[PT], d[F50], and d[V50] were significantly higher in M− and MX groups compared with control M group. Whereas d[PT], d[F50], and d[V50] parameters of the F− group were significantly higher than control F group, d[F50] and d[PT] of the FX group showed no significant change and d[V50] for the FX group was significantly lower. A comparison of control groups showed that d[PT], d[F50], and d[V50] of the F group were significantly higher than those of the M group.

Conclusion

Whereas absence of both testosterone and estradiol caused an increase in hypocalcemia-induced changes in contraction parameters of rat skeletal muscle, presence or application of testosterone clearly stabilized contraction parameters.