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1.
World J Urol ; 39(10): 3861-3866, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33866401

ABSTRACT

PURPOSE: The aim of this study was to assess the post biopsy infection rate, feasibility and prostate cancer (PCa) detection rate (CDR) by performing transperineal MRI-TRUS fusion biopsy of the prostate (TPBx) under local anesthesia (LA) without antibiotic prophylaxis (AP). METHODS: We prospectively screened 766 men with suspicious lesions on mpMRI, an elevated PSA level or a suspect digital examination undergoing MRI-TRUS-TPBx in LA, from May 2019 to July 2020. Patients with the need for antibiotic prophylaxis or without a PI-RADS target lesion were excluded from final analyses. We reported CDR, perioperative pain (0-10) and postoperative complications. PCa with an ISUP grade ≥ 2 was classified as clinically significant PCa (csPCa). RESULTS: We included 621 patients with a median age of 68 years (IQR 62-74), a PSA of 6.43 ng/mL (IQR 4.72-9.91) and a prostate volume of 45 cc (IQR 32-64). In median, 4 targeted (TB) (IQR 3-4) and 6 (IQR 5-7) systematic biopsies (SB) detected in combination overall 416 (67%) PCa and 324 (52%) csPCa. Overall CDR of TB for PI-RADS 3, 4 and 5 was 26%, 65% and 84%, respectively. Patients reported a median perioperative pain level of 2 (IQR 1-3). Four patients (0.6%) developed a post biopsy infection, one experienced urosepsis. CONCLUSION: Our results demonstrate that transperineal MRI-TRUS fusion-guided prostate biopsy under LA without AP is feasible, safe and well tolerated.


Subject(s)
Image-Guided Biopsy/methods , Prostatic Neoplasms/pathology , Sepsis/epidemiology , Surgical Wound Infection/epidemiology , Urinary Tract Infections/epidemiology , Aged , Anesthesia, Local , Antibiotic Prophylaxis/methods , Endosonography , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Multiparametric Magnetic Resonance Imaging , Perineum , Prostate/pathology , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/diagnostic imaging , Retrospective Studies
2.
J Sex Med ; 18(3): 632-645, 2021 03.
Article in English | MEDLINE | ID: mdl-33642235

ABSTRACT

BACKGROUND: The number of adolescents presenting with gender dysphoria (GD) in healthcare services has increased significantly, yet specialized services offering transition-related care (TRC) for trans youth is lacking. AIM: To investigate satisfaction with TRC, regret, and reasons for (dis)satisfaction with transition-related medical interventions (TRMIs) in trans adolescents who had presented to the Hamburg Gender Identity Service for children and adolescents (Hamburg GIS). METHODS: Data were collected from a clinical cohort sample of 75 adolescents and young adults diagnosed with GD (81% assigned female at birth) aged 11 to 21 years (M = 17.4) at baseline and follow-up (on a spectrum of ongoing care, on average 2 years after initial consultation). To determine progress of the youth's medical transitions, an individual treatment progress score (ITPS) was calculated based on number of desired vs received TRMIs. OUTCOMES: Main outcome measures were satisfaction with TRC at the time of follow-up, ITPS, social support, reasons for regret and termination of TRC, and (dis)satisfaction with TRMIs. RESULTS: Participants underwent different stages of TRMIs, such as gender-affirming hormone treatment or surgeries, and showed overall high satisfaction with TRC received at the Hamburg GIS. Regression analysis indicated that a higher ITPS (an advanced transition treatment stage) was predictive of higher satisfaction with TRC. Sex assigned at birth, age, and time since initial consultation at the clinic showed no significant effects for satisfaction with TRC, while degree of social support showed a trend. No adolescents regretted undergoing treatment at follow-up. Additional analysis of free-text answers highlighted satisfaction mostly with the physical results of TRMI. CLINICAL IMPLICATIONS: Because youth were more satisfied with TRC when their individual transition (ITPS) was more progressed, treatment should start in a timely manner to avoid distress from puberty or long waiting lists. STRENGTHS AND LIMITATIONS: This study is one of the first to report on treatment satisfaction among youth with GD from Europe. The ITPS allowed for a more detailed evaluation of TRMI wishes and experiences in relation to satisfaction with TRC and may close a gap in research on these treatments in adolescent populations. However, all participants were from the same clinic, and strict treatment eligibility criteria may have excluded certain trans adolescents from the study. Low identification rates with non-binary identities prevented comparisons between non-binary and binary genders. CONCLUSION: The study highlights the role of TRMI and individual treatment or transition progress for youth's overall high satisfaction with TRC received at the Hamburg GIS. Nieder TO, Mayer TK, Hinz S, et al. Individual Treatment Progress Predicts Satisfaction With Transition-Related Care for Youth With Gender Dysphoria: A Prospective Clinical Cohort Study. J Sex Med 2021;18:632-645.


Subject(s)
Gender Dysphoria , Transgender Persons , Adolescent , Adult , Child , Cohort Studies , Europe , Female , Gender Dysphoria/therapy , Gender Identity , Humans , Male , Personal Satisfaction , Prospective Studies , Young Adult
3.
Urologe A ; 59(10): 1225-1230, 2020 Oct.
Article in German | MEDLINE | ID: mdl-32161979

ABSTRACT

The perineal approach for prostate biopsy (PB) is a sterile alternative to conventional transrectal PB. Targeted local anesthesia allows perineal prostate biopsy (pPB) to be performed without general anesthesia. This paper presents the first results after establishing perineal MRI/ultrasound fusion biopsy (pFB) under local anesthesia without standard perioperative antibiotic prophylaxis. For this purpose, 144 patients were included in the study after pFB at the Vivantes Klinikum am Urban. No peri-interventional antibiotic prophylaxis was applied. Peri- and postoperatively, the pain sensation, measured using an analogue pain scale from 0-10, and complications were recorded. The median patient age was 68 and the median prostate-specific antigen (PSA) value 7.07 ng/ml. In all, 49% of the patients received primary PB. The overall detection rate for prostate cancer (PCa) was 71% and for PI-RADS 3, 4 and 5 was 44, 71 and 92%, respectively. The median pain sensation during biopsy was 2. Furthermore, 63% of patients with a transrectal prebiopsy considered this to be more painful and another 20% expressed similar pain levels. Only 1 patient developed a febrile urinary tract infection. The pFB of the prostate under local anesthesia without antibiotic, perioperative prophylaxis is a suitable alternative to the transrectal PB with regard to the detection rate of PCa, the side effect profile and the subjective pain perception of the patients during the intervention.


Subject(s)
Anesthesia, Local , Prostatic Neoplasms , Antibiotic Prophylaxis , Humans , Image-Guided Biopsy , Magnetic Resonance Imaging , Male , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/surgery
4.
BMC Cancer ; 19(1): 429, 2019 May 09.
Article in English | MEDLINE | ID: mdl-31072339

ABSTRACT

BACKGROUND: Despite rising incidence rates of colorectal malignancies, only a few prognostic tools have been implemented in proven clinical routine. Cell division and proliferation play a significant role in malignancies. In terms of colorectal cancer, the impact of proliferation associated proteins is controversially debated. The aim of our study was to examine the expression of topoisomerase II α and minichromosome maintenance protein 6 and to correlate these findings with the clinical data. METHODS: Tissue samples of 619 patients in total were stained using the antibodies Ki-S4 and Ki-MCM6 targeting topoisomerase II α as well as minichromosome maintenance protein 6. The median rate of proliferation was correlated with clinical and follow up data. RESULTS: The expression rate of minichromosome maintenance protein 6 is significantly higher than the proportion of topoisomerase II α in tumour cells (p < 0.001). A high expression of both proteins coincides with a beneficial outcome for the patient, indicating a favourable prognostic marker (p < 0.001 and p = 0.008). CONCLUSIONS: We have demonstrated that high expression rates of proliferative markers is linked to a beneficial patient outcome. According to the general opinion, a high expression rate correlates with a poor patient outcome. In this study, we were able to refute this assertion.


Subject(s)
Biomarkers, Tumor/metabolism , Colorectal Neoplasms/pathology , DNA Topoisomerases, Type II/metabolism , Minichromosome Maintenance Complex Component 6/metabolism , Poly-ADP-Ribose Binding Proteins/metabolism , Aged , Cell Proliferation , Colon/pathology , Colon/surgery , Colorectal Neoplasms/mortality , Colorectal Neoplasms/surgery , Disease-Free Survival , Female , Humans , Male , Middle Aged , Prognosis , Rectum/pathology , Rectum/surgery , Retrospective Studies , Survival Analysis
5.
Chirurg ; 88(5): 411-421, 2017 May.
Article in German | MEDLINE | ID: mdl-28451729

ABSTRACT

Pylorus-preserving pancreaticoduodenectomy is one of the most complex procedures in general surgery. Laparoscopic pancreaticoduodenectomy was initially described in 1994; however, its worldwide distribution is so far limited to only a few specialist centers. Robotic surgery using the DaVinci® system can overcome many limitations of laparoscopic surgery. The system is a promising tool for a more widespread introduction of minimally invasive surgery for pancreatic diseases. Mortality rates of 0-5% and pancreatic fistula rates of 0-35% are described in the literature; therefore, thorough complication management is crucial in the postoperative course. The video presents a robotic pylorus-preserving pancreaticoduodenectomy for periampullary carcinoma in a female patient.


Subject(s)
Adenocarcinoma/surgery , Ampulla of Vater/surgery , Common Bile Duct Neoplasms/surgery , Pancreaticoduodenectomy/methods , Robotic Surgical Procedures/methods , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/pathology , Aged , Ampulla of Vater/diagnostic imaging , Ampulla of Vater/pathology , Cholestasis, Intrahepatic/diagnostic imaging , Cholestasis, Intrahepatic/surgery , Common Bile Duct Neoplasms/diagnostic imaging , Common Bile Duct Neoplasms/pathology , Female , Humans , Jejunostomy/instrumentation , Jejunostomy/methods , Laparoscopy/instrumentation , Laparoscopy/methods , Neoplasm Staging , Pancreaticoduodenectomy/instrumentation , Pancreaticojejunostomy/instrumentation , Pancreaticojejunostomy/methods , Robotic Surgical Procedures/instrumentation , Suture Techniques/instrumentation , Tomography, X-Ray Computed
6.
Zentralbl Chir ; 141(2): 139-41, 2016 Apr.
Article in German | MEDLINE | ID: mdl-27074208

ABSTRACT

BACKGROUND: The surgical treatment of pancreatic head tumours is one of the most complex procedures in general surgery. In contrast to colorectal surgery, minimally-invasive techniques are not very commonly applied in pancreatic surgery. Both the delicate dissection along peri- and retropancreatic vessels and the extrahepatic bile ducts and subsequent reconstruction are very demanding with rigid standard laparoscopic instruments. The 4-arm robotic surgery system with angled instruments, unidirectional movement of instruments with adjustable transmission, tremor elimination and a stable, surgeon-controlled 3D-HD view is a promising platform to overcome the limitations of standard laparoscopic surgery regarding precise dissection and reconstruction in pancreatic surgery. INDICATION: Pancreatic head resection for mixed-type IPMN of the pancreatic head. PROCEDURE: Robot-assisted, minimally-invasive pylorus-preserving pancreaticoduodenectomy (Kausch-Whipple procedure). CONCLUSION: The robotic approach is particularly suited for complex procedures such as pylorus-preserving pancreatic head resections. The fully robotic Kausch-Whipple procedure is technically feasible and safe. The advantages of the robotic system are apparent in the delicate dissection near vascular structures, in lymph node dissection, the precise dissection of the uncinate process and, especially, bile duct and pancreatic anastomosis.


Subject(s)
Carcinoma, Pancreatic Ductal/surgery , Laparoscopy/instrumentation , Laparoscopy/methods , Pancreatic Neoplasms/surgery , Pancreaticoduodenectomy/instrumentation , Pancreaticoduodenectomy/methods , Robotic Surgical Procedures/instrumentation , Robotic Surgical Procedures/methods , Aged , Anastomosis, Surgical/instrumentation , Anastomosis, Surgical/methods , Dissection/instrumentation , Dissection/methods , Feasibility Studies , Female , Gastrostomy/instrumentation , Gastrostomy/methods , Humans , Jejunostomy/instrumentation , Jejunostomy/methods , Pylorus/surgery , Surgical Equipment , Surgical Instruments
7.
Urologe A ; 54(8): 1115-7, 2015 Aug.
Article in German | MEDLINE | ID: mdl-25821170

ABSTRACT

Sertoli cell tumors are a rare malignancy which account for approximately 1.5 % of all testicular tumors. Although malignant Sertoli cell tumors are uncommon, they are associated with a poor prognosis. So far 36 cases of malignant courses of disease have been described. We present a patient with a lymphogenic metastasized Sertoli cell tumor, who 24 months after orchiectomy and extended retroperitoneal lymphadenectomy is relapse-free.


Subject(s)
Lymph Node Excision/methods , Orchiectomy/methods , Sertoli Cell Tumor/secondary , Sertoli Cell Tumor/surgery , Testicular Neoplasms/secondary , Testicular Neoplasms/surgery , Adult , Combined Modality Therapy/methods , Humans , Male , Sertoli Cell Tumor/pathology , Testicular Neoplasms/pathology , Treatment Outcome
8.
Aktuelle Urol ; 46(1): 45-51, 2015 Jan.
Article in German | MEDLINE | ID: mdl-25526221

ABSTRACT

INTRODUCTION: The optimal surgical treatment of patients with a high risk prostate cancer (PCa) in terms of radical prostatectomy (RP) is still controversial: open retropubic RP (RRP), laparoscopic RP (LRP), or robot-assisted (RARP). We aimed to investigate the influence of the different surgical techniques on pathologic outcome and biochemical recurrence. PATIENTS AND METHODS: A total of 805 patients with a high risk PCa (PSA >20 ng/mL, Gleason Score ≥8, or clinical stage ≥cT2c) were included. A comparison of 407 RRP patients with 398 minimally invasive cases (LRP+RARP) revealed significant confounders. Therefore all 110 RARP cases were propensity score (PS) matched 1:1 with LRP and RRP patients. PS included age, clinical stage, preoperative PSA, biopsy Gleason score, surgeon's experience and application of a nerve sparing technique. Comparison of overall survival (OS) and recurrence-free survival (RFS) was done with the log rank test. Predictors of RFS were analyzed by means of Cox regression models. RESULTS: Within the post-matching cohort of 330 patients a pathologic Gleason score < 7, = 7 and > 7 was found in 1.8, 55.5 and 42.7% for RARP, in 8.2, 36.4, 55.5% for LRP and in 0, 60.9 and 39.1% for RRP (p=0.004 for RARP vs. LRP and p=0.398 for RARP vs. RRP). Differences in histopathologic stages were not statistically significant. The overall positive surgical margin rate (PSM) as well as PSM for ≥ pT3 were not different. PSM among patients with pT2 was found in 15.7, 14.0 and 20.0% for RARP, LRP and RRP (statistically not significant). The respective mean 3-year RFS rates were 41.4, 77.9, 54.1% (p<0.0001 for RARP vs. LRP and p=0.686 for RARP vs. RRP). The mean 3-year OS was calculated as 95.4, 98.1 and 100% respectively (statistically not significant). CONCLUSION: RARP for patients with a high risk PCa reveals similar pathologic and oncologic outcomes compared with LRP and RRP.


Subject(s)
Laparoscopy/methods , Propensity Score , Prostatectomy/methods , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Robotic Surgical Procedures/methods , Aged , Biomarkers, Tumor/blood , Case-Control Studies , Cohort Studies , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Recurrence, Local/blood , Neoplasm Recurrence, Local/etiology , Neoplasm Staging , Postoperative Complications/blood , Postoperative Complications/etiology , Prostate/pathology , Prostate-Specific Antigen/blood , Risk Factors , Treatment Outcome
9.
J Vet Intern Med ; 28(5): 1414-7, 2014.
Article in English | MEDLINE | ID: mdl-25146756

ABSTRACT

BACKGROUND: Vomiting is a common complication associated with the use of hydromorphine for pre-emptive analgesia in dogs. The ideal anti-emetic protocol for prevention of this complication has not been established. HYPOTHESIS: Maropitant administered concurrently or before hydromorphone would reduce the incidence of vomiting, signs of nausea, ptyalism, and increased panting compared to administration of acepromazine or a 0.9% saline control. ANIMALS: Sixty mixed-breed female dogs scheduled for ovariohysterectomy. METHODS: Randomized, blinded, placebo-controlled experimental study. Dogs were assigned to 4 experimental groups with 15 dogs per group. All groups received 0.2 mg/kg of hydromorphone IM. Group "Control" received 0.1 mL/kg saline SC 30-45 minutes before hydromorphone, group "Marop1" received 1 mg/kg maropitant SC 30-45 minutes before hydromorphone, group "Ace" received 0.02 mg/kg IM acepromazine 30-45 minutes before hydromorphone, and group "Marop2" received 1 mg/kg SC maropitant concurrently with hydromorphone. A trained and blinded observer documented adverse events from the time hydromorphone was administered until the time dogs were induced for surgery. RESULTS: Marop1 had significantly less vomiting (0%) compared to Control (87%; P < .01) and Ace (53%; P < .01). Marop2 had significantly less vomiting (27%) compared to Control (P < .01). Marop1 had significantly greater incidence of ptyalism (73%) compared to Ace (P < .01; 20%). Ace showed significantly less panting (33%) compared to Marop2 (93%; P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE: In healthy dogs, maropitant citrate administered before hydromorphone significantly decreases the incidence of vomiting in dogs but does not improve signs of nausea, ptyalism, or increased panting.


Subject(s)
Acepromazine/therapeutic use , Analgesics, Opioid/adverse effects , Antiemetics/therapeutic use , Dog Diseases/chemically induced , Hydromorphone/adverse effects , Postoperative Nausea and Vomiting/veterinary , Quinuclidines/therapeutic use , Animals , Dog Diseases/prevention & control , Dogs , Female , Hysterectomy/adverse effects , Hysterectomy/veterinary , Incidence , Ovariectomy/adverse effects , Ovariectomy/veterinary , Postoperative Nausea and Vomiting/chemically induced , Postoperative Nausea and Vomiting/prevention & control
10.
Case Rep Nephrol Urol ; 4(1): 1-4, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24575115

ABSTRACT

Within the evaluation process of living kidney donors, split renal function is usually evaluated by renal scintigraphy. Since split renal function measured by conventional posterior scans depends on the position of the kidney, actual suitable donors may be rejected because of an inaccurate examination technique. We report the case of a 28-year-old male living kidney donor. Due to a complex vascular anatomy of the right kidney, only his left kidney was considered eligible for transplantation. In conventional posterior Tc99m-mercapto-acetyltriglycine scintigraphy, the left kidney had a relative function of 60%. A second scintigraphy using anterior and posterior dimercaptosuccinic acid scans with calculation of the geometric mean showed an adapted relative function of the left kidney of 53%, now meeting the inclusion criteria for living kidney donation. This case shows that the geometric mean method using simultaneous anterior and posterior views obtained with a dual-head gamma camera can be a very helpful approach to determine split renal function of potential living kidney donors. Further investigation is necessary to prove the benefit of a general bilateral scan before living kidney donation.

11.
J Biotechnol ; 168(4): 684-92, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24140638

ABSTRACT

Mass spectrometric analysis was used to compare the roles of two acetyl esterases (AE, carbohydrate esterase family CE16) and three acetyl xylan esterases (AXE, families CE1 and CE5) in deacetylation of natural substrates, neutral (linear) and 4-O-methyl glucuronic acid (MeGlcA) substituted xylooligosaccharides (XOS). AEs were similarly restricted in their action and apparently removed in most cases only one acetyl group from the non-reducing end of XOS, acting as exo-deacetylases. In contrast, AXEs completely deacetylated longer neutral XOS but had difficulties with the shorter ones. Complete deacetylation of neutral XOS was obtained after the combined action of AEs and AXEs. MeGlcA substituents partially restricted the action of both types of esterases and the remaining acidic XOS were mainly substituted with one MeGlcA and one acetyl group, supposedly on the same xylopyranosyl residue. These resisting structures were degraded to great extent only after inclusion of α-glucuronidase, which acted with the esterases in a synergistic manner. When used together with xylan backbone degrading endoxylanase and ß-xylosidase, both AE and AXE enhanced the hydrolysis of complex XOS equally.


Subject(s)
Acetylesterase/chemistry , Glucuronates/chemistry , Oligosaccharides/chemistry , Xylans/chemistry , Acetylation , Acetylesterase/metabolism , Aspergillus niger/enzymology , Endo-1,4-beta Xylanases/chemistry , Endo-1,4-beta Xylanases/metabolism , Glycoside Hydrolases/chemistry , Hydrolysis , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Substrate Specificity , Xylans/metabolism
12.
Enzyme Microb Technol ; 53(1): 25-32, 2013 Jun 10.
Article in English | MEDLINE | ID: mdl-23683701

ABSTRACT

Two novel GH11 endo-xylanases from Myceliophthora thermophila C1 (C1), Xyl7 and Xyl8, were purified and the influence of solubility and molecular structure of various xylans on their efficiency was investigated. Both endo-xylanases were hindered by a high degree of substitution of a xylan. The two GH11 xylanases released different products from the xylans, in which Xyl7 displayed a degradation product composition closer to GH10 xylanases. A correlation of the degradation product composition with a specific residue at position 163 in the amino acid sequence of Xyl8 is suggested: tyrosine in Xyl8; valine in Xyl7. This is confirmed with examples of various endo-xylanases reported in literature. The C1 GH11 xylanases were more efficient on self-associated xylan compared to C1 GH10 endo-xylanases and they released more small xylooligomers from these xylans. This is contrary to the general assumption that GH10 xylanases degrade xylans to a higher degree than GH11 xylanases.


Subject(s)
Endo-1,4-beta Xylanases , Sordariales/enzymology , Xylans/metabolism , Amino Acid Sequence , Endo-1,4-beta Xylanases/chemistry , Endo-1,4-beta Xylanases/classification , Endo-1,4-beta Xylanases/metabolism , Fungal Proteins/chemistry , Fungal Proteins/metabolism , Kinetics , Models, Molecular , Molecular Sequence Data , Sequence Analysis, DNA , Solubility , Sordariales/classification , Substrate Specificity , Xylans/chemistry
13.
Biochemistry (Mosc) ; 77(11): 1303-11, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23240568

ABSTRACT

Genes of ß-mannosidase 97 kDa, GH family 2 (bMann9), ß-mannanase 48 kDa, GH family 5 (bMan2), and α-galactosidase 60 kDa, GH family 27 (aGal1) encoding galactomannan-degrading glycoside hydrolases of Myceliophthora thermophila C1 were successfully cloned, and the recombinant enzymes were purified to homogeneity and characterized. bMann9 displays only exo-mannosidase activity, the K(m) and k(cat) values are 0.4 mM and 15 sec(-1) for p-nitrophenyl-ß-D-mannopyranoside, and the optimal pH and temperature are 5.3 and 40°C, respectively. bMann2 is active towards galactomannans (GM) of various structures. The K(m) and k(cat) values are 1.3 mg/ml and 67 sec(-1) for GM carob, and the optimal pH and temperature are 5.2 and 69°C, respectively. aGal1 is active towards p-nitrophenyl-α-D-galactopyranoside (PNPG) as well as GM of various structures. The K(m) and k(cat) values are 0.08 mM and 35 sec(-1) for PNPG, and the optimal pH and temperature are 5.0 and 60°C, respectively.


Subject(s)
Fungal Proteins/metabolism , Glycoside Hydrolases/metabolism , Sordariales/enzymology , Amino Acid Sequence , Cloning, Molecular , Fungal Proteins/chemistry , Fungal Proteins/genetics , Glycoside Hydrolases/chemistry , Glycoside Hydrolases/genetics , Hydrogen-Ion Concentration , Kinetics , Molecular Sequence Data , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Substrate Specificity , Temperature
14.
Bioresour Technol ; 119: 123-32, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22728192

ABSTRACT

Xylanases are mostly classified as belonging to glycoside hydrolase (GH) family 10 and 11, which differ in catalytic properties and structures. However, within one family, differences may also be present. The influence of solubility and molecular structure of substrates towards the efficiency of two GH10 xylanases from Myceliophthora thermophila C1 was investigated. The xylanases differed in degradation of high and low substituted substrate and the substitution pattern was an important factor influencing their efficiency. Alkali-labile interactions, as well as the presence of cellulose within the complex cell wall structure hindered efficient hydrolysis for both xylanases. The presence of a carbohydrate binding module did not enhance the degradation of the substrates. The differences in degradation could be related to the protein structure of the two xylanases. The study shows that the classification of enzymes does not predict their performance towards various substrates.


Subject(s)
Ascomycota/classification , Ascomycota/enzymology , Cellulose/chemistry , Endo-1,4-beta Xylanases/chemistry , Xylans/chemistry , Enzyme Activation , Enzyme Stability , Protein Binding , Solubility , Species Specificity
15.
Bioresour Technol ; 112: 345-9, 2012 May.
Article in English | MEDLINE | ID: mdl-22429400

ABSTRACT

The Bxl5-gene encoding a GH3 glycoside hydrolase of Chrysosporium lucknowense C1 was successfully cloned, the homologous recombinant product was secreted, purified and characterized. Bxl5 (120 ± 5 kDa) was able to hydrolyze low molecular weight substrates and polysaccharides containing ß-glucosidic as well as ß-xylosidic residues. The K(m) and V(max)/E values were found to be 0.3mM and 88 s(-1) on p-nitrophenyl-ß-d-glucopyranoside (PNPG), and 13.5mM and 1.8s(-1) on p-nitrophenyl-ß-d-xylopyranoside (PNPX). Optimal pH and temperature for Bxl5 were 4.6 and 75°C for the PNPG hydrolysis, and 5.0-5.5 and 70°C for PNPX hydrolysis. The enzyme was quite stable when incubated at elevated temperatures up to 65°C. Bxl5 hydrolyzes polymeric ß-glucans by the exo-mechanism allowing their complete conversion to d-glucose and is effective for xylan hydrolysis in combination with endo-acting xylan-degrading enzymes. The enzyme seems to be a very promising for bioconversion purposes.


Subject(s)
Chrysosporium/enzymology , Glycoside Hydrolases/metabolism , Xylans/metabolism , beta-Glucans/metabolism , Chrysosporium/drug effects , Enzyme Inhibitors/pharmacology , Enzyme Stability/drug effects , Extracellular Space/drug effects , Extracellular Space/enzymology , Glycoside Hydrolases/antagonists & inhibitors , Glycoside Hydrolases/isolation & purification , Hordeum/drug effects , Hordeum/metabolism , Hydrogen-Ion Concentration/drug effects , Hydrolysis/drug effects , Kinetics , Mass Spectrometry , Molecular Sequence Data , Sequence Homology, Amino Acid , Substrate Specificity/drug effects , Temperature
16.
Carbohydr Res ; 352: 65-9, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22436888

ABSTRACT

Statistical modeling was applied for describing structural features of ß-(1→4)-D-galactomannans. According to the model suggested theoretical ratios of limiting degrees of locust bean, tara gum and guar gum galactomannan conversions by two ß-(1→4)-mannanases of different origin (Myceliophthora thermophila and Trichoderma reesei) were calculated. Then the enzymes were tested for enzymatic hydrolysis of three considered galactomannans. Experimentally observed results were compared with theoretically calculated ones. It was shown that T. reesei ß-mannanase attacks sequences of four and more unsubstituted mannopyranosyl residues in a row, while M. thermophila ß-mannanase is a more specific enzyme and attacks sequences of five and more mannopyranosyl residues in a row. Considered statistical model and approach allows to characterize both galactomannan structures and enzyme requirements for regions of unsubstituted mannose residues for substrate hydrolysis.


Subject(s)
Mannans/chemistry , Plants/metabolism , beta-Mannosidase/metabolism , Galactose/analogs & derivatives , Hydrolysis , Sordariales/enzymology , Substrate Specificity , Trichoderma/enzymology
17.
Enzyme Microb Technol ; 50(1): 77-85, 2012 Jan 05.
Article in English | MEDLINE | ID: mdl-22133444

ABSTRACT

Three ferulic acid esterases from the filamentous fungus Chrysosporium lucknowense C1 were purified and characterized. The enzymes were most active at neutral pH and temperatures up to 45 °C. All enzymes released ferulic acid and p-coumaric acid from a soluble corn fibre fraction. Ferulic acid esterases FaeA1 and FaeA2 could also release complex dehydrodiferulic acids and dehydrotriferulic acids from corn fibre oligomers, but released only 20% of all ferulic acid present in sugar beet pectin oligomers. Ferulic acid esterase FaeB2 released almost no complex ferulic acid oligomers from corn fibre oligomers, but 60% of all ferulic acid from sugar beet pectin oligomers. The ferulic acid esterases were classified based on both, sequence similarity and their activities toward synthetic substrates. The type A ferulic acid esterases FaeA1 and FaeA2 are the first members of the phylogenetic subfamily 5 to be biochemically characterized. Type B ferulic acid esterase FaeB2 is a member of subfamily 6.


Subject(s)
Biofuels , Carboxylic Ester Hydrolases/isolation & purification , Chrysosporium/enzymology , Biomass , Carboxylic Ester Hydrolases/classification , Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/metabolism , Chrysosporium/genetics , Coumaric Acids/metabolism , Fungal Proteins/classification , Fungal Proteins/genetics , Fungal Proteins/isolation & purification , Fungal Proteins/metabolism , Genes, Fungal , Hydrogen-Ion Concentration , Pectins/metabolism , Substrate Specificity , Temperature , Xylans/metabolism
18.
Enzyme Microb Technol ; 49(3): 312-20, 2011 Aug 10.
Article in English | MEDLINE | ID: mdl-22112517

ABSTRACT

Two novel acetyl xylan esterases, Axe2 and Axe3, from Chrysosporium lucknowense (C1), belonging to the carbohydrate esterase families 5 and 1, respectively, were purified and biochemically characterized. Axe2 and Axe3 are able to hydrolyze acetyl groups both from simple acetylated xylo-oligosaccharides and complex non-soluble acetylglucuronoxylan. Both enzymes performed optimally at pH 7.0 and 40 °C. Axe2 has a clear preference for acetylated xylo-oligosaccharides (AcXOS) with a high degree of substitution and Axe3 does not show such preference. Axe3 has a preference for large AcXOS (DP 9-12) when compared to smaller AcXOS (especially DP 4-7) while for Axe2 the size of the oligomer is irrelevant. Even though there is difference in substrate affinity towards acetylated xylooligosaccharides from Eucalyptus wood, the final hydrolysis products are the same for Axe2 and Axe3: xylo-oligosaccharides containing one acetyl group located at the non-reducing xylose residue remain as examined using MALDI-TOF MS, CE-LIF and the application of an endo-xylanase (GH 10).


Subject(s)
Acetylesterase/metabolism , Biofuels , Chrysosporium/enzymology , Fungal Proteins/metabolism , Xylans/metabolism , Acetylation , Acetylesterase/classification , Acetylesterase/genetics , Acetylesterase/isolation & purification , Chrysosporium/genetics , Electrophoresis, Capillary , Eucalyptus , Fluorometry , Fungal Proteins/genetics , Fungal Proteins/isolation & purification , Hydrogen-Ion Concentration , Hydrolysis , Industrial Microbiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Substrate Specificity , Temperature , Wood
19.
Urologe A ; 50(9): 1083-8, 2011 Sep.
Article in German | MEDLINE | ID: mdl-21728009

ABSTRACT

The introduction of prostate cancer treatment centers according to the criteria of the German Cancer Society ("Deutsche Krebsgesellschaft", DKG) aims at improving the quality of care for patients with prostate cancer. Systematic analyses of the effects and costs are lacking as yet. Three years after certification of the Interdisciplinary Prostate Cancer Center at the Charité Hospital Berlin we observed a decrease in the rate of positive surgical margins (tumor stage pT2), but other parameters of treatment quality including patient satisfaction remained unchanged. A survey among urologists of the region showed a high acceptance of prostate cancer centers in general. The majority of participating urologists appreciated the work of the Charité center, in particular the treatment recommendations given by the center were mostly followed and the majority of urologists regularly use educational activities of the center. However, only 30% of the participating urologists confirmed short-term improvements in the quality of patient care. Yearly additional costs for the Charité prostate cancer center are estimated at 205,000 euro (precertification phase and certification) and 138,000 euro (monitoring phase), despite the initial drop in mean treatment costs per case (radical prostatectomy). The introduction of prostate cancer treatment centers certified by the DKG is cost intensive, increases in treatment efficiency notwithstanding. Short-term improvements in quality of care cannot be unequivocally demonstrated. Prostate cancer centers serve an important role in counseling and medical education and may thus help disseminate evidence-based treatment strategies.


Subject(s)
Accreditation , Cancer Care Facilities , Cooperative Behavior , Interdisciplinary Communication , Prostatic Neoplasms/surgery , Societies, Medical , Voluntary Health Agencies , Accreditation/economics , Cancer Care Facilities/economics , Cost-Benefit Analysis , Data Collection , Germany , Humans , Laparoscopy/economics , Male , National Health Programs/economics , Neoplasm Staging , Patient Satisfaction/economics , Prostatectomy/economics , Prostatic Neoplasms/economics , Prostatic Neoplasms/pathology , Quality Assurance, Health Care/economics , Referral and Consultation/economics , Reoperation/economics , Societies, Medical/economics , Voluntary Health Agencies/economics
20.
Bioresour Technol ; 102(2): 1636-43, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20933404

ABSTRACT

The mode of action of four Chrysosporium lucknowense C1 α-L-arabinohydrolases was determined to enable controlled and effective degradation of arabinan. The active site of endoarabinanase Abn1 has at least six subsites, of which the subsites -1 to +2 have to be occupied for hydrolysis. Abn1 was able to hydrolyze a branched arabinohexaose with a double substituted arabinose at subsite -2. The exo acting enzymes Abn2, Abn4 and Abf3 release arabinobiose (Abn2) and arabinose (Abn4 and Abf3) from the non-reducing end of reduced arabinose oligomers. Abn2 binds the two arabinose units only at the subsites -1 and -2. Abf3 prefers small oligomers over large oligomers. It is able to hydrolyze all linkages present in beet arabinan, including the linkages of double substituted residues. Abn4 is more active towards polymeric substrate and releases arabinose monomers from single substituted arabinose residues. Depending on the combination of the enzymes, the C1 arabinohydrolases can be used to effectively release branched arabinose oligomers and/or arabinose monomers.


Subject(s)
Arabinose/metabolism , Chrysosporium/enzymology , Glycoside Hydrolases/metabolism , Arabinose/chemistry , Chrysosporium/drug effects , Enzyme Inhibitors/pharmacology , Glycoside Hydrolases/antagonists & inhibitors , Molecular Weight , Oligosaccharides/metabolism , Protein Isoforms/metabolism , Substrate Specificity/drug effects , Time Factors
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