Molecular identification and whole genome sequence analyses of methicillin-resistant and mastitis-associated Staphylococcus aureus sequence types 6 and 2454 isolated from dairy cows.

The emergence of antimicrobial-resistant and mastitis-associated Staphylococcus aureus is of great concern due to the huge economic losses worldwide. Here, we report draft genome sequences of two Staphylococcus aureus strains which were isolated from raw milk samples obtained from mastitis-infected cows in Bangladesh. The strains were isolated and identified using conventional microbiological and molecular polymerase chain reaction (PCR) methods. Antibiotic susceptibility testing was performed. Genomic DNA of the two strains was extracted and the strains were sequenced using the Illumina NextSeq 550 platform. The assembled contigs were analyzed for virulence determinants, antimicrobial resistance genes, extra-chromosomal plasmids, and multi-locus sequence type (MLST). The genomes of the two strains were compared with other publicly available genome sequences of Staphylococcus aureus strains. The raw read sequences were downloaded and all sequence files were analyzed identically to generate core genome phylogenetic trees. The genome of BR-MHR281strain did not harbour any antibiotic resistance determinants, however BR-MHR220 strain harbored mecA and blaZ genes. Analysis of BR-MHR220 strain revealed that it was assigned to sequence type (ST-6), clonal complex (CC) 5 and spa type t304, while BR-MHR281 strain belonged to ST-2454, CC8, and harbored the spa type t7867. The findings of the present study and the genome sequences of BR-MHR220 and BR-MHR281 strains will provide data on the detection and genomic analysis and characterization of mastitis-associated Staphylococcus aureus in Bangladesh. In addition, the findings of the present study will serve as reference genomes for future molecular epidemiological studies and will provide significant data which help understand the prevalence, pathogenesis and antimicrobial resistance of mastitis-associated Staphylococcus aureus.

Bacterial flagella hijack type IV pili proteins to control motility.

Bacterial flagella and type IV pili (TFP) are surface appendages that enable motility and mechanosensing through distinct mechanisms. These structures were previously thought to have no components in common. Here, we report that TFP and some flagella share proteins PilO, PilN, and PilM, which we identified as part of the Helicobacter pylori flagellar motor. H. pylori mutants lacking PilO or PilN migrated better than wild type in semisolid agar because they continued swimming rather than aggregated into microcolonies, mimicking the TFP-regulated surface response. Like their TFP homologs, flagellar PilO/PilN heterodimers formed a peripheral cage that encircled the flagellar motor. These results indicate that PilO and PilN act similarly in flagella and TFP by differentially regulating motility and microcolony formation when bacteria encounter surfaces.

Characterisation and mitigation of gas leaks at laparoscopy: an international prospective, multi-center cohort clinical trial.

INTRODUCTION: Gas leaks polluting the operating room are common in laparoscopy. Studies defining methods for sensitive leak characterisation and mechanical mitigation in real world settings are, however, lacking. METHODS: Mobile optical gas imagers (both a miniaturised Schlieren system and sensitive tripod-mounted near-infrared carbon dioxide camera (GF343, FLIR)) prospectively defined trocar-related gas leaks occurring either spontaneously or with instrumentation during planned laparoscopic surgery at three hospitals. A boutique Matlab-based analyser using sequential frame subtraction categorised leaks (class 0-no observable leak; class 1-marginally detectable leak; class 2-short-lived plume; class 3-energetic, turbulent jet). Concurrently, the usefulness of a novel vacuum-ring device (LeakTrap™, Palliare, Ireland) designed as a universal adjunct for existing standard laparoscopic ports at both abdominal wall and port valve level was determined similarly in a phase I/11 clinical trial along with the device's useability through procedural observation and surgeon questionnaire. RESULTS: With ethical and regulatory approval, 40 typical patients (mean age 58.6 years, 20 males) undergoing planned laparoscopic cholecystectomy (n = 36) and hernia repair (n = 4) were studied comprising both control (n = 20) and intervention (n = 20) cohorts. Dual optical gas imaging was successfully performed across all procedures with minimal impact on procedural flow. In total, 1643 trocar instrumentations were examined, 819 in the control group (mean 41 trocar instrumentations/procedure) and 824 in the intervention group (mean 41.2 trocar instrumentations/procedure). Gas leaks were detected during 948(62.6%) visualised trocar instrumentations (in 129-7.8%-the imaging was obscured). 14.8% (110/742) and 60% (445/742) of leaks in control patients were class 0 and 3, respectively, versus 59.1% (456/770) and 8.7% (67/772) in the interventional group (class 3 v non-class 3, p < 0.0001, χ2). The Leaktrap proved surgically acceptable without significant workflow disruption. CONCLUSION: Laparoscopic gas leaks can be sensitively detected and consistently, effectively mitigated using straightforward available-now technology with most impact on the commonest, highest energy instrument exchange leaks.

Pal power: Demonstration of the functional association of the Helicobacter pylori flagellar motor with peptidoglycan-associated lipoprotein (Pal) and its preliminary crystallographic analysis.

The bacterial flagellar motor is a molecular nanomachine, the assembly and regulation of which requires many accessory proteins. Their identity, structure and function are often discovered through characterisation of mutants with impaired motility. Here, we demonstrate the functional association of the Helicobacter pylori peptidoglycan-associated lipoprotein (HpPal) with the flagellar motor by analysing the motility phenotype of the ∆pal mutant, and present the results of the preliminary X-ray crystallographic analysis of its globular C-terminal domain HpPal-C. Purified HpPal-C behaved as a dimer in solution. Crystals of HpPal-C were grown by the hanging drop vapour diffusion method using medium molecular weight polyethylene glycol (PEG) Smear as the precipitating agent. The crystals belong to the primitive orthorhombic space group P1 with unit cell parameters a = 50.7, b = 63.0, c = 75.1 Å. X-ray diffraction data were collected to 1.8 Å resolution on the Australian Synchrotron beamline MX2. Calculation of the Matthews coefficient (VM=2.24 Å3/Da) and molecular replacement showed that the asymmetric unit contains two protein subunits. This study is an important step towards elucidation of the non-canonical role of H. pylori Pal in the regulation, or function of, the flagellar motor.

The use of fluorescence angiography to assess bowel viability in the acute setting: an international, multi-centre case series.

INTRODUCTION: Assessing bowel viability can be challenging during acute surgical procedures, especially regarding mesenteric ischaemia. Intraoperative fluorescence angiography (FA) may be a valuable tool for the surgeon to determine whether bowel resection is necessary and to define the most appropriate resection margins. The aim of this study is to report on FA use in the acute setting and to judge its impact on intraoperative decision making. MATERIALS AND METHODS: This is a multi-centre, retrospective case series of patients undergoing emergency abdominal surgery between February 2016 and 2021 in three general/colorectal units where intraoperative FA was performed to assess bowel viability. Primary endpoint was change of management after the FA assessment. RESULTS: A total of 93 patients (50 males, 66.6 ± 19.2 years, ASA score ≥ III in 85%) were identified and studied. Initial surgical approach was laparotomy in 66 (71%) patients and laparoscopy in 27 (29% and seven, 26% conversions). The most common aetiologies were mesenteric ischaemia (n = 42, 45%) and adhesional/herniae-related strangulation (n = 41, 44%). In 50 patients a bowel resection was performed. Overall rates of anastomosis after resection, reoperation and 30-day mortality were 48% (n = 24/50, one leak), 12% and 18%, respectively. FA changed management in 27 (29%) patients. In four patients (4% overall), resection was avoided and in 21 (23%) extra bowel length was preserved (median 50 cm of bowel saved, IQR 28-98) although three patients developed further ischaemia. FA prompted extended resection (median of 20 cm, IQR 10-50 extra bowel) in six (6%) patients. CONCLUSION: Intraoperative use of FA impacts surgical decisions regarding bowel resection for intestinal ischaemia, potentially enabling bowel preservation in approximately one out of four patients. Prospective studies are needed to optimize the best use of this technology for this indication and to determine standards for the interpretation of FA images and the potential subsequent need for second-look surgeries.

The flagellar motor protein FliL forms a scaffold of circumferentially positioned rings required for stator activation.

The flagellar motor stator is an ion channel nanomachine that assembles as a ring of the MotA5MotB2 units at the flagellar base. The role of accessory proteins required for stator assembly and activation remains largely enigmatic. Here, we show that one such assembly factor, the conserved protein FliL, forms an integral part of the Helicobacter pylori flagellar motor in a position that colocalizes with the stator. Cryogenic electron tomography reconstructions of the intact motor in whole wild-type cells and cells lacking FliL revealed that the periplasmic domain of FliL (FliL-C) forms 18 circumferentially positioned rings integrated with the 18 MotAB units. FliL-C formed partial rings in the crystal, and the crystal structure-based full ring model was consistent with the shape of the rings observed in situ. Our data suggest that each FliL ring is coaxially sandwiched between the MotA ring and the dimeric periplasmic MotB moiety of the stator unit and that the central hole of the FliL ring has density that is consistent with the plug/linker region of MotB in its extended, active conformation. Significant structural similarities were found between FliL-C and stomatin/prohibitin/flotillin/HflK/C domains of scaffolding proteins, suggesting that FliL acts as a scaffold. The binding energy released upon association of FliL with the stator units could be used to power the release of the plug helices. The finding that isolated FliL-C forms stable partial rings provides an insight into the putative mechanism by which the FliL rings assemble around the stator units.

In Vitro User Assessment of a Novel Wound Protection and Specimen Extraction System for Laparoscopic Procedures Involving Morcellation.

INTRODUCTION: The risk of unknowingly disseminating leiomyosarcoma by morcellation in women undergoing laparoscopic hysterectomy has massively impacted gynaecological practice. Here, we present the results of an in vitro assessment of a novel protection system developed to mitigate this hazard. METHODS: The Tissue Containment System for Manual Morcellation (Guardenia™, Advanced Surgical Concepts, Wicklow, Ireland) is an evolved wound protection/specimen extraction guarded bag system compatible with any 12mm trocar. Device use was assessed by device-naïve gynaecological and general surgeon volunteers (providing expert and inexpert morcellation cohorts, respectively) on a bench model consisting of biological tissue in a custom-built moulded rig with camera control after the operators were instructed in its use. RESULTS: Twenty surgeons (10 gynaecologists/10 general surgeons, median duration of practice experience: 8 years, median annual number of laparoscopic operative procedures: 150 and 80, respectively) completed the user assessment. All subjects understood and correctly performed each step; i.e., (i) placement of the bag through the trocar, (ii) specimen bagging, (iii) incision extension (range 25-60 mm) after tethering the bag through the port, (iv) insertion of the device guard through the mouth of the bag after trocar removal, and (v) sufficient tissue morcellation within the bag to enable complete specimen removal (mean specimen weight 390g, range 201-1800g). There was 100% bag integrity by water-leak testing following use, despite scalpel contact with the guard in 14/20 cases (70%). CONCLUSION: Among first-time clinical users, this novel device enabled complete containment of morcellation debris and removal of a laparoscopic specimen, which would support further submission for regulatory approval.

Structure-Activity Relationship Study Reveals the Molecular Basis for Specific Sensing of Hydrophobic Amino Acids by the Campylobacter jejuni Chemoreceptor Tlp3.

Chemotaxis is an important virulence factor of the foodborne pathogen Campylobacter jejuni. Inactivation of chemoreceptor Tlp3 reduces the ability of C. jejuni to invade human and chicken cells and to colonise the jejunal mucosa of mice. Knowledge of the structure of the ligand-binding domain (LBD) of Tlp3 in complex with its ligands is essential for a full understanding of the molecular recognition underpinning chemotaxis. To date, the only structure in complex with a signal molecule is Tlp3 LBD bound to isoleucine. Here, we used in vitro and in silico screening to identify eight additional small molecules that signal through Tlp3 as attractants by directly binding to its LBD, and determined the crystal structures of their complexes. All new ligands (leucine, valine, α-amino-N-valeric acid, 4-methylisoleucine, ß-methylnorleucine, 3-methylisoleucine, alanine, and phenylalanine) are nonpolar amino acids chemically and structurally similar to isoleucine. X-ray crystallographic analysis revealed the hydrophobic side-chain binding pocket and conserved protein residues that interact with the ammonium and carboxylate groups of the ligands determine the specificity of this chemoreceptor. The uptake of hydrophobic amino acids plays an important role in intestinal colonisation by C. jejuni, and our study suggests that C. jejuni seeks out hydrophobic amino acids using chemotaxis.

Broad Specificity of Amino Acid Chemoreceptor CtaA of Pseudomonas fluorescens Is Afforded by Plasticity of Its Amphipathic Ligand-Binding Pocket.

Motile bacteria follow gradients of nutrients or other environmental cues. Many bacterial chemoreceptors that sense exogenous amino acids contain a double Cache (dCache; calcium channels and chemotaxis receptors) ligand-binding domain (LBD). A growing number of studies suggest that broad-specificity dCache-type receptors that sense more than one amino acid are common. Here, we present an investigation into the mechanism by which the dCache LBD of the chemoreceptor CtaA from a plant growth-promoting rhizobacterium, Pseudomonas fluorescens, recognizes several chemically distinct amino acids. We established that amino acids that signal by directly binding to the CtaA LBD include ones with aliphatic (l-alanine, l-proline, l-leucine, l-isoleucine, l-valine), small polar (l-serine), and large charged (l-arginine) side chains. We determined the structure of CtaA LBD in complex with different amino acids, revealing that its ability to recognize a range of structurally and chemically distinct amino acids is afforded by its easily accessible plastic pocket, which can expand or contract according to the size of the ligand side chain. The amphipathic character of the pocket enables promiscuous interactions with both polar and nonpolar amino acids. The results not only clarify the means by which various amino acids are recognized by CtaA but also reveal that a conserved mobile lid over the ligand-binding pocket adopts the same conformation in all complexes, consistent with this being an important and invariant part of the signaling mechanism.

Molecular Basis of Unexpected Specificity of ABC Transporter-Associated Substrate-Binding Protein DppA from Helicobacter pylori.

The gastric pathogen Helicobacter pylori has limited ability to use carbohydrates as a carbon source, relying instead on exogenous amino acids and peptides. Uptake of certain peptides by H. pylori requires an ATP binding cassette (ABC) transporter annotated dipeptide permease (Dpp). The transporter specificity is determined by its cognate substrate-binding protein DppA, which captures ligands in the periplasm and delivers them to the permease. Here, we show that, unlike previously characterized DppA proteins, H. pylori DppA binds, with micromolar affinity, peptides of diverse amino acid sequences ranging between two and eight residues in length. We present analysis of the 1.45-Å-resolution crystal structure of its complex with the tetrapeptide STSA, which provides a structural rationale for the observed broad specificity. Analysis of the molecular surface revealed a ligand-binding pocket that is large enough to accommodate peptides of up to nine residues in length. The structure suggests that H. pylori DppA is able to recognize a wide range of peptide sequences by forming interactions primarily with the peptide main chain atoms. The loop that terminates the peptide-binding pocket in DppAs from other bacteria is significantly shorter in the H. pylori protein, providing an explanation for its ability to bind longer peptides. The subsites accommodating the two N-terminal residues of the peptide ligand make the greatest contribution to the protein-ligand binding energy, in agreement with the observation that dipeptides bind with affinity close to that of longer peptides.IMPORTANCE The World Health Organization listed Helicobacter pylori as a high-priority pathogen for antibiotic development. The potential of using peptide transporters in drug design is well recognized. We discovered that the substrate-binding protein of the ABC transporter for peptides, termed dipeptide permease, is an unusual member of its family in that it directly binds peptides of diverse amino acid sequences, ranging between two and eight residues in length. We also provided a structural rationale for the observed broad specificity. Since the ability to import peptides as a source of carbon is critical for H. pylori, our findings will inform drug design strategies based on inhibition or fusion of membrane-impermeant antimicrobials with peptides.

Theoretically Guided Analytical Method Development and Validation for the Estimation of Rifampicin in a Mixture of Isoniazid and Pyrazinamide by UV Spectrophotometer.

A simple, rapid, economic, accurate, and precise method for the estimation of rifampicin in a mixture of isoniazid and pyrazinamide by UV spectrophotometeric technique (guided by the theoretical investigation of physicochemical properties) was developed and validated. Theoretical investigations revealed that isoniazid and pyrazinamide both were freely soluble in water and slightly soluble in ethyl acetate whereas rifampicin was practically insoluble in water but freely soluble in ethyl acetate. This indicates that ethyl acetate is an effective solvent for the extraction of rifampicin from a water mixture of isoniazid and pyrazinamide. Computational study indicated that pH range of 6.0-8.0 would favor the extraction of rifampicin. Rifampicin is separated from isoniazid and pyrazinamide at pH 7.4 ± 0.1 by extracting with ethyl acetate. The ethyl acetate was then analyzed at λmax of 344.0 nm. The developed method was validated for linearity, accuracy and precision according to ICH guidelines. The proposed method exhibited good linearity over the concentration range of 2.5-35.0 µg/mL. The intraday and inter-day precision in terms of % RSD ranged from 1.09 to 1.70% and 1.63 to 2.99%, respectively. The accuracy (in terms of recovery) of the method varied from of 96.7 ± 0.9 to 101.1 ± 0.4%. The LOD and LOQ were found to be 0.83 and 2.52 µg/mL, respectively. In addition, the developed method was successfully applied to determine rifampicin combination (isoniazid and pyrazinamide) brands available in Bangladesh.

Lean management in health care: definition, concepts, methodology and effects reported (systematic review protocol).

BACKGROUND: Lean is a set of operating philosophies and methods that help create a maximum value for patients by reducing waste and waits. It emphasizes the consideration of the customer's needs, employee involvement and continuous improvement. Research on the application and implementation of lean principles in health care has been limited. METHODS: This is a protocol for a systematic review, following the Cochrane Effective Practice and Organisation of Care (EPOC) methodology. The review aims to document, catalogue and synthesize the existing literature on the effects of lean implementation in health care settings especially the potential effects on professional practice and health care outcomes. We have developed a Medline keyword search strategy, and this focused strategy will be translated into other databases. All search strategies will be provided in the review. The method proposed by the Cochrane EPOC group regarding randomized study designs, non-randomised controlled trials controlled before and after studies and interrupted time series will be followed. In addition, we will also include cohort, case-control studies, and relevant non-comparative publications such as case reports. We will categorize and analyse the review findings according to the study design employed, the study quality (low- versus high-quality studies) and the reported types of implementation in the primary studies. We will present the results of studies in a tabular form. DISCUSSION: Overall, the systematic review aims to identify, assess and synthesize the evidence to underpin the implementation of lean activities in health care settings as defined in this protocol. As a result, the review will provide an evidence base for the effectiveness of lean and implementation methodologies reported in health care. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42014008853.

Associated liver enzymes with hyperlipidemic profile in type 2 diabetes patients.

Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia and is associated with dyslipidemia and disturbed liver function. Aim of the present work is to assess the liver enzymes and to find its association with hyperlipidemic profile in T2DM. Total of 157 subjects were studied and divided into two groups; diabetes (n=81) and non-diabetes (n=76). Various biochemical parameters like fasting glucose, post prandial glucose, HbA1c, total cholesterol (TC), triglycerides (Tg), high density lipoprotein cholesterol (HDL-C), alanine amino transferase (ALT), aspartate amino transferase (AST) and gamma-glutamyl transferase (GGT) were analyzed by ROCHE module Cobas 6000 (C501 & C601) analyzer, kits were procured by ROCHE diagnostics. Low density lipoprotein cholesterol (LDL-C) was estimated by Freidwald's formula. Statistical analysis was performed by applying student t test and Pearson's correlation coefficient, at 0.0001 and 0.05 level of significance, respectively. All the glycemic control parameters, lipid profile parameters except HDL-C and liver enzymes were found increased in diabetes group and significantly differ from non-diabetes group (p>0.0001). ALT showed significant positive correlation with fasting glucose, post prandial glucose, HbA1c, TC, Tg, LDL-C and GGT at p>0.05. AST showed very weak relation with all parameters while GGT was positively associated with fasting glucose, post prandial glucose, HbA1c, TC, Tg, LDL-C and ALT at p>0.05. In conclusion, T2DM incline to elevate liver enzymes, especially ALT and GGT were of significance. Routine screening of ALT and GGT in T2DM patients may assists early detection of liver abnormalities and to arrest the progress of disease.

Labda-8(17),12,14-trien-19-oic acid contained in fruits of Cupressus sempervirens suppresses benign prostatic hyperplasia in rat and in vitro human models through inhibition of androgen and STAT-3 signaling.

Fruit extract of Cupressus sempervirens (CS), which is used traditionally to treat Benign Prostatic Hyperplasia (BPH)-like urinary symptoms in patients, was scientifically validated for anti-BPH activity. The ethanolic fruit extract of CS inhibited proliferation of human BPH-stromal cells and the activity was localized to its chloroform-soluble, diterpene-rich fraction. Eight major diterpenes isolated from this fraction exhibited moderate to potent activity and the most active diterpene (labda-8(17),12,14-trien-19-oic acid) exhibited an IC50 of 37.5 µM (antiproliferative activity against human BPH-stromal cells). It significantly inhibited activation (phosphorylation) of Stat-3 in BPH-stromal cells and prevented transactivation of androgen sensitive KLK3/PSA and TMPRSS2 genes in LNCaP cells. Labda-8(17),12,14-trien-19-oic acid-rich CS fraction prevented prostatic hyperplasia in rat model and caused TUNEL labeling of stromal cells with lower expressions of IGF-I, TGF-ß and PCNA, and bcl-2/bax ratio. Human BPH tissues exhibited precise lowering of stromal component after incubation in labda-8(17),12,14-trien-19-oic acid, ex vivo. We conclude that labda-8(17),12,14-trien-19-oic acid contained in CS exhibits anti-BPH activity through inhibition of stromal proliferation and suppression of androgen action in the prostate, presenting a unique lead structure for further optimization of anti-BPH activity.

Constituents from fruits of Cupressus sempervirens.

Two new phenolic glycosides (1, 2), along with fourteen known compounds (3-16) have been isolated from the fruit of Cupressus sempervirens. The structures of these compounds were determined by spectroscopic analysis and were evaluated for their inhibitory activity against glycogen phosphorylase and glucose-6-phosphatase enzymes. Compounds 14 showed a moderate inhibition against glucose-6-phosphatase and 15 against glycogen phosphorylase enzymes.

Liver metastases in rats: chemoembolization combined with interstitial laser ablation for treatment.

PURPOSE: To assess the effect of transcatheter arterial chemoembolization (TACE) combined with laser-induced thermotherapy (LITT) for treatment of liver metastases in an animal model. MATERIALS AND METHODS: All experiments were approved by the German government and the institutional animal research review board. After subcapsular liver implantation of colorectal cancer cells in 30 WAG rats (on day 0), the animals were randomly assigned to three interventional treatment groups. In the 10 rats in group A, TACE was performed: Fourteen days after cancer cell implantation and within 20 minutes after laparotomy and retrograde placement of a microcatheter into the gastroduodenal artery, these rats were injected with mitomycin (0.1 mg), iodized oil (0.1 mL), and degradable starch microspheres (5.0 mg). In the 10 rats in group B, LITT was performed: Also on day 14, the tumors in these animals were exposed to Nd:YAG laser light of 1064 nm at 2 W for 5 minutes. In the 10 rats in group C, combined treatment was administered: TACE was performed on day 14, and LITT was performed on day 21. Tumor volumes were measured before (on day 13) and after (on day 28) treatment with magnetic resonance (MR) imaging, and the mean tumor growth ratio (day 13 tumor volume divided by day 28 tumor volume) was calculated. RESULTS: The mean tumor volumes measured before and after the treatments were, respectively, 0.11 and 0.60 cm(3) in group A, 0.11 and 0.68 cm(3) in group B, and 0.11 and 0.35 cm(3) in group C. The mean tumor growth ratio was 5.42 in group A, 6.14 in group B, and 3.15 in group C. According to Bonferroni test results, compared with the rats in groups A and B (controls), the group C rats had significantly inhibited tumor growth (P < .01 for both comparisons). CONCLUSION: Use of combined TACE-LITT treatment, compared with the use of TACE or LITT alone, significantly inhibits tumor growth.

Quantitative cartilage volume measurement using MRI: comparison of different evaluation techniques.

This study was aimed to investigate the accuracy and time saving of MRI Argus application in the assessment of cartilage volume in osteoarthritic knees. Twelve knees of patients suffering from osteoarthritis were scanned with a 1.5 T MRI using a 3D gradient echo sequence with selective water excitation. Cartilage volume of the tibial and patellar compartment was determined with a validated multiprocessing computer system (Octane Duo, Silicon Graphics, Mountain View, Calif., USA). The calculated cartilage volumes were compared to the results acquired by the Argus (Siemens Inc., Erlangen, Germany) application software using the MRI data sets. Compared to the multiprocessing computer system a time saving of at least 30 min for cartilage volume determination was achieved. The mean differences of Argus versus the multiprocessing computer system were 4.26+/-0.84 and 7.80+/-0.87% for the medial and lateral tibial plateau and 5.94+/-0.59% for the patella (no statistical significant difference; P>0.05). The applied Argus software can be used for fast and accurate determination of cartilage volume in the knee joint.

Minimally invasive versus conventional aortic valve replacement: a prospective randomized trial.

BACKGROUND AND AIM OF THE STUDY: A prospective randomized study was performed to compare conventional with minimally invasive aortic valve replacement (AVR). METHODS: Forty consecutive patients scheduled for elective aortic valve surgery were prospectively randomized either to the conventional group (group A, complete median sternotomy) or minimally invasive group (group B, partial upper sternotomy). Intraoperative and postoperative clinical data, and markers of myocardial and cerebral protection were determined. Neuropsychological tests were carried out to quantify psychological disorders. RESULTS: Operative time and cardiopulmonary bypass time were slightly longer in group B, but not significantly so. No significant inter-group differences were found for postoperative pain scores and respiratory function. Chest tube drainage was significantly less in group B (495 +/- 165 versus 240 +/- 69 ml, p = 0.008). Creatine kinase (CK), CK-MB and troponin T levels were similar in both groups. Neither S-100B protein nor neuron-specific enolase levels differed significantly between groups at all sampling times. There were no strokes in the entire cohort. None of the neuropsychological tests yielded significant inter-group differences between conventional and minimally invasive surgery. CONCLUSION: The safety and reliability of AVR via a partial upper sternotomy is reported. Minimally invasive AVR can be performed with only slightly longer operative times, good cosmetic results and significantly less blood loss. A limited surgical access affected neither the patients' neurological outcome nor the efficacy of myocardial protection.