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1.
Opt Express ; 30(17): 31122-31135, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-36242201

ABSTRACT

We explore the use of femtosecond laser pulses to clean a variety of colors of spray paint from the Moruya granite, a stone with high heritage value that is widely used for monuments and sculptures in Sydney and New South Wales (Australia). The efficiency of the cleaning treatment and the effects on the stone substrate are evaluated using optical microscopy, optical profilometry, Raman spectroscopy, energy-dispersive X-ray spectroscopy, and colorimetry. We demonstrate that femtosecond laser cleans granite without damaging it and without discoloration when the laser fluence is set below the damage threshold of the stone.

2.
Ned Tijdschr Geneeskd ; 1662022 03 17.
Article in Dutch | MEDLINE | ID: mdl-35499618

ABSTRACT

We describe an 11-year-old boy with sudden onset of right groin pain which occurred during soccer. He was diagnosed with an avulsion fracture of the lesser trochanter, a hyperextension and rotation trauma due to traction on the iliopsoas tendon. The treatment was conservative and full function returned.


Subject(s)
Fractures, Bone , Soccer , Child , Femur/injuries , Groin , Humans , Male , Pelvic Pain
3.
Anaesthesia ; 75(12): 1596-1604, 2020 12.
Article in English | MEDLINE | ID: mdl-33090469

ABSTRACT

Maintaining safe elective surgical activity during the global coronavirus disease 2019 (COVID-19) pandemic is challenging and it is not clear how COVID-19 may impact peri-operative morbidity and mortality in this population. Therefore, adaptations to normal care pathways are required. Here, we establish if implementation of a bespoke peri-operative care bundle for urgent elective surgery during a pandemic surge period can deliver a low COVID-19-associated complication profile. We present a single-centre retrospective cohort study from a tertiary care hospital of patients planned for urgent elective surgery during the initial COVID-19 surge in the UK between 29 March and 12 June 2020. Patients asymptomatic for COVID-19 were screened by oronasal swab and chest imaging (chest X-ray or computed tomography if aged ≥ 18 years), proceeding to surgery if negative. COVID-19 positive patients at screening were delayed. Postoperatively, patients transitioning to COVID-19 positive status by reverse transcriptase polymerase chain reaction testing were identified by an in-house tracking system and monitored for complications and death within 30 days of surgery. Out of 557 patients referred for surgery (230 (41.3%) women; median (IQR [range]) age 61 (48-72 [1-89])), 535 patients (96%) had COVID-19 screening, of which 13 were positive (2.4%, 95%CI 1.4-4.1%). Out of 512 patients subsequently undergoing surgery, 7 (1.4%) developed COVID-19 positive status (1.4%, 95%CI 0.7-2.8%) with one COVID-19-related death (0.2%, 95%CI 0.0-1.1%) within 30 days. Out of these seven patients, four developed pneumonia, of which two required invasive ventilation including one patient with acute respiratory distress syndrome. Low rates of COVID-19 infection and mortality in the elective surgical population can be achieved within a targeted care bundle. This should provide reassurance that elective surgery can continue, where possible, despite high community rates of COVID-19.


Subject(s)
Coronavirus Infections/epidemiology , Elective Surgical Procedures , Perioperative Period , Pneumonia, Viral/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19 , Child , Child, Preschool , Cohort Studies , Coronavirus Infections/diagnosis , Coronavirus Infections/transmission , Female , Humans , Infant , Male , Mass Screening , Middle Aged , Pandemics , Pneumonia/epidemiology , Pneumonia/etiology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/transmission , Postoperative Complications/epidemiology , Postoperative Complications/mortality , Respiration, Artificial , Retrospective Studies , Tertiary Care Centers , Young Adult
4.
BMC Vet Res ; 16(1): 409, 2020 Oct 29.
Article in English | MEDLINE | ID: mdl-33121487

ABSTRACT

BACKGROUND: Meckel's diverticula are a rare cause of small intestinal strangulation, diagnosed at laparotomy or necropsy. This congenital anomaly of the gastrointestinal tract originates from a remnant of the vitelline duct. In reported equine cases, they present as a full-thickness diverticulum on the antimesenteric border of the distal jejunum or proximal ileum. CASE PRESENTATION: On laparotomy a Meckel's diverticulum positioned at the mesenteric side was found to be the cause of small intestinal strangulation. This position is very uncommon and to the best knowledge of the authors there is no unambiguous description of another case. CONCLUSIONS: Meckel's diverticula should be on the list of differential diagnoses in cases of small intestinal strangulation. As in humans, equine Meckel's diverticula can have the standard antimesenteric as well as a more exceptional mesenteric location. This case adds to the series of anecdotal reports of anomalies with regard to Meckel's diverticula in the horse.


Subject(s)
Intestinal Obstruction/veterinary , Meckel Diverticulum/veterinary , Abdominal Pain/diagnosis , Abdominal Pain/etiology , Abdominal Pain/veterinary , Animals , Female , Horses , Intestinal Obstruction/diagnosis , Intestinal Obstruction/surgery , Laparotomy/veterinary , Meckel Diverticulum/diagnosis , Meckel Diverticulum/surgery , Mesentery/pathology , Mesentery/surgery
5.
Phys Rev Lett ; 124(7): 073401, 2020 Feb 21.
Article in English | MEDLINE | ID: mdl-32142320

ABSTRACT

The introduction of optical tweezers for trapping atoms has opened remarkable opportunities for manipulating few-body systems. Here, we present the first bottom-up assembly of atom triads. We directly observe atom loss through inelastic collisions at the single event level, overcoming the substantial challenge in many-atom experiments of distinguishing one-, two-, and three-particle processes. We measure a strong suppression of three-body loss, which is not fully explained by the presently availably theory for three-body processes. The suppression of losses could indicate the presence of local anticorrelations due to the interplay of attractive short range interactions and low dimensional confinement. Our methodology opens a promising pathway in experimental few-body dynamics.

7.
Unfallchirurg ; 123(3): 225-237, 2020 Mar.
Article in German | MEDLINE | ID: mdl-32077972

ABSTRACT

Lesions of peripheral nerves substantially influence the long-term prognosis and functional outcome. Approximately 70% of peripheral nerval lesions are associated with vascular injuries and occur more frequently with certain fractures and osteosynthesis types. The prognosis and treatment depend on the severity of the injury and the presence of axonal lesions, in particular, determines the further procedure. Treatment as early as possible is associated with a clear improvement in the prognosis. Defects longer than 8 mm in size necessitate a nerve transplantation. Iatrogenic vascular lesions occur particularly in percutaneous interventions and are reported in up to 8% of cases after operations involving the musculoskeletal system. Iatrogenic nerve lesions are almost exclusively the result of surgical procedures and represent up to 17.5% of traumatic nerve injuries. For all lesions the general principles of surgical treatment are valid and the rapid involvement of professional expertise is decisive.


Subject(s)
Fractures, Bone , Neuromuscular Diseases , Peripheral Nerve Injuries , Extremities , Fractures, Bone/complications , Humans , Iatrogenic Disease , Neuromuscular Diseases/etiology , Peripheral Nerve Injuries/etiology , Treatment Outcome
8.
Plant Biol (Stuttg) ; 22 Suppl 1: 123-132, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31532043

ABSTRACT

The stimulatory effect of elevated [CO2 ] (e[CO2 ]) on crop production in future climates is likely to be cancelled out by predicted increases in average temperatures. This effect may become stronger through more frequent and severe heat waves, which are predicted to increase in most climate change scenarios. Whilst the growth and yield response of some legumes grown under the interactive effect of e[CO2 ] and heat waves has been studied, little is known about how N2 fixation and overall N metabolism is affected by this combination. To address these knowledge gaps, two lentil genotypes were grown under ambient [CO2 ] (a[CO2 ], ~400 µmol·mol-1 ) and e[CO2 ] (~550 µmol·mol-1 ) in the Australian Grains Free Air CO2 Enrichment facility and exposed to a simulated heat wave (3-day periods of high temperatures ~40 °C) at flat pod stage. Nodulation and concentrations of water-soluble carbohydrates (WSC), total free amino acids, N and N2 fixation were assessed following the imposition of the heat wave until crop maturity. Elevated [CO2 ] stimulated N2 fixation so that total N2 fixation in e[CO2 ]-grown plants was always higher than in a[CO2 ], non-stressed control plants. Heat wave triggered a significant decrease in active nodules and WSC concentrations, but e[CO2 ] had the opposite effect. Leaf N remobilization and grain N improved under interaction of e[CO2 ] and heat wave. These results suggested that larger WSC pools and nodulation under e[CO2 ] can support post-heat wave recovery of N2 fixation. Elevated [CO2 ]-induced accelerated leaf N remobilisation might contribute to restore grain N concentration following a heat wave.


Subject(s)
Carbon Dioxide , Hot Temperature , Lens Plant , Nitrogen Fixation , Nitrogen , Australia , Carbon Dioxide/metabolism , Carbon Dioxide/pharmacology , Environment , Lens Plant/drug effects , Lens Plant/growth & development , Lens Plant/metabolism , Nitrogen/metabolism
9.
Anaesthesia ; 75(2): 162-170, 2020 02.
Article in English | MEDLINE | ID: mdl-31270799

ABSTRACT

NHS England recently mandated that the National Early Warning Score of vital signs be used in all acute hospital trusts in the UK despite limited validation in the postoperative setting. We undertook a multicentre UK study of 13,631 patients discharged from intensive care after risk-stratified cardiac surgery in four centres, all of which used VitalPACTM to electronically collect postoperative National Early Warning Score vital signs. We analysed 540,127 sets of vital signs to generate a logistic score, the discrimination of which we compared with the national additive score for the composite outcome of: in-hospital death; cardiac arrest; or unplanned intensive care admission. There were 578 patients (4.2%) with an outcome that followed 4300 sets of observations (0.8%) in the preceding 24 h: 499 out of 578 (86%) patients had unplanned re-admissions to intensive care. Discrimination by the logistic score was significantly better than the additive score. Respective areas (95%CI) under the receiver-operating characteristic curve with 24-h and 6-h vital signs were: 0.779 (0.771-0.786) vs. 0.754 (0.746-0.761), p < 0.001; and 0.841 (0.829-0.853) vs. 0.813 (0.800-0.825), p < 0.001, respectively. Our proposed logistic Early Warning Score was better than the current National Early Warning Score at discriminating patients who had an event after cardiac surgery from those who did not.


Subject(s)
Cardiac Surgical Procedures/mortality , Early Warning Score , Heart Arrest/diagnosis , Intensive Care Units , Patient Readmission/statistics & numerical data , Humans , Predictive Value of Tests , Reproducibility of Results , Sensitivity and Specificity , United Kingdom
11.
Unfallchirurg ; 122(7): 555-572, 2019 Jul.
Article in German | MEDLINE | ID: mdl-31270552

ABSTRACT

Neurovascular injuries in fractures threaten at least the function of extremities. The timely interaction between diagnosis and treatment of vascular injuries helps to avoid a poor outcome or even fatal complications. An important parameter is to "think about it" for injuries under strain. An ankle-brachial index (ABI) of <0.9 is an indicator. Massive bleeding, manifest and long-lasting peripheral ischemia and a rapidly expanding hematoma necessitate an immediate surgical intervention. Endovascular techniques are recommended on the extremities of stable patients with circumscribed vascular lesions. The debate about the sequence of repair (vascular vs. osseous) has to be decided on an individual basis; however, when in doubt vascular repair should be given priority. Vessel reconstructions should be performed without tension and must be covered by vital soft tissues, the indications for fasciotomy should be liberally interpreted. The prognosis with respect to preservation of the extremity and long-term functional outcome substantially depends on the quality of treatment of accompanying injuries.


Subject(s)
Fractures, Bone , Vascular System Injuries , Extremities , Fasciotomy , Humans , Vascular Surgical Procedures
12.
Unfallchirurg ; 122(4): 328-332, 2019 Apr.
Article in German | MEDLINE | ID: mdl-30859241

ABSTRACT

BACKGROUND: Decentralized trauma care in the Wald and Weinviertel region in the north of lower Austria comprises five hospitals for primary care including one regional trauma center. Due to the geographical position and adverse weather conditions a web-based teleradiology system was established to ensure the best possible treatment and joint access to the results of radiological investigations. OBJECTIVE: The article describes a new picture archiving and communication system (PACS), which provides an online teleradiological workflow between the central trauma care unit and peripheral departments in a local trauma network as well as the advantages and disadvantages. MATERIAL AND METHODS: A corporately used PACS enables streaming-based full access to studies which are created within the system. Radiological studies can be obtained on request from all subscribers within the network. RESULTS: Teleradiological networks can essentially contribute to a suitable treatment pathway in an association of hospitals and therefore lead to a rapid initiation of treatment. CONCLUSION: Especially in rural areas with decentralized trauma care, the joint use of teleradiological resources can lead to a better treatment quality.


Subject(s)
Teleradiology/methods , Wounds and Injuries/diagnostic imaging , Austria , Delivery of Health Care , Humans , Quality of Health Care , Radiology Information Systems , Rural Population , Trauma Centers
13.
Oral Dis ; 24(8): 1388-1389, 2018 11.
Article in English | MEDLINE | ID: mdl-29363231

ABSTRACT

Taste receptor cells in the tongue are epithelial in nature and turnover frequently. Taste receptor cell-associated neurons carrying bitter, sweet, or sour signals never turnover and are hardwired to specific gustatory centers in the brain. How can ever-changing bitter or sweet receptors find never-changing neurons that must match the specificity of the signal? This article reviews a recent paper published in Nature (Lee, MacPherson, Parada, Zuker, & Ryba, , 548:330-333) that identified two molecules belonging to the semaphorin axon guidance family of molecules (SEMA3A and SEMA7A) that help maintain the "labeled line principle" between peripheral bitter or sweet receptors and their respective central projection area in the gustatory center.


Subject(s)
Taste Buds , Taste , Neurons , Taste Perception , Tongue
14.
BJA Educ ; 18(1): 16-22, 2018 Jan.
Article in English | MEDLINE | ID: mdl-33456790
15.
Unfallchirurg ; 120(9): 745-752, 2017 Sep.
Article in German | MEDLINE | ID: mdl-28623468

ABSTRACT

BACKGROUND: The monitoring of intracranial pressure (ICP) represents a cornerstone in the intensive care of patients with traumatic brain injury (TBI) and the industry provides various technical solutions to this end. Decompressive craniectomy can be an option if conservative measures fail to reduce excessive ICP. OBJECTIVE: To examine the pathophysiology of ICP in trauma, the management of polytrauma involving TBI, and the indications for decompressive craniectomy; and to compare the different monitoring systems and their complications. MATERIAL AND METHODS: A retrospective analysis of TBI patients between 2010 and 2016 was performed. Relevant publications are discussed, particularly those relating to the indications for monitoring and its influence on polytrauma management. RESULTS: Between 2010 and 2016, 106 patients with closed TBI and a mean age of 65.9 years received a total of 120 ICP monitors, most of which were parenchyma devices (111/120), followed by intraventricular catheters (8/120), and one combined system (1/120). Of these patients, 27.4% had sustained polytrauma, whilst 33% regularly used anticoagulants. ICP monitors were removed after 8.5 days on an average and the mean ICU stay was 20 days. Probe insertion was combined with craniectomy in 69.8% patients. Probe-related complications, most commonly involving malfunction, were seen in 6.6%. The duration of monitoring was significantly related to polytrauma (p ≤ 0.001) and age <60 (p = 0.03). ICU stay was also significantly related to polytrauma (p = 0.02) and monitoring complications (p ≤ 0.001). Mortality was related to anticoagulant medication (p = 0.01) and age <60 (p = 0.03). CONCLUSIONS: ICP monitoring is one of the most important tools in TBI treatment. The course and outcome of these severe injuries is affected by polytrauma, age, and the use of anticoagulants.


Subject(s)
Brain Injuries, Traumatic/therapy , Intracranial Pressure/physiology , Monitoring, Physiologic , Multiple Trauma/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Brain Injuries, Traumatic/diagnosis , Brain Injuries, Traumatic/physiopathology , Cerebrovascular Circulation/physiology , Craniotomy , Critical Care , Female , Glasgow Coma Scale , Humans , Male , Middle Aged , Monitoring, Physiologic/instrumentation , Multiple Trauma/diagnosis , Multiple Trauma/physiopathology , Retrospective Studies , Young Adult
16.
Phys Rev Lett ; 118(10): 107001, 2017 Mar 10.
Article in English | MEDLINE | ID: mdl-28339246

ABSTRACT

Charge transport has been examined in junctions comprising the normal-metal tip of a low-temperature scanning tunneling microscope, the surface of a conventional superconductor, and adsorbed C_{60} molecules. The Bardeen-Cooper-Schrieffer energy gap gradually evolves into a zero-bias peak with decreasing electrode separation. The peak is assigned to the spectroscopic signature of Andreev reflection. The conductance due to Andreev reflection is determined by the atomic termination of the tip apex and the molecular adsorption orientation. Transport calculations unveil the finite temperature and the strong molecule-electrode hybridization as the origin to the surprisingly good agreement between spectroscopic data and the Blonder-Tinkham-Klapwijk model that was conceived for macroscopic point contacts.

17.
Hernia ; 21(2): 305-315, 2017 04.
Article in English | MEDLINE | ID: mdl-28012032

ABSTRACT

BACKGROUND: New biodegradable synthetic and biologic hernia implants have been promoted for rapid integration and tissue reinforcement in challenging repairs, e.g. at the hiatus or in contaminated wound fields. Interestingly, experimental data to support or falsify this assumption is scarce. METHODS: Synthetic (BioA®) and biologic implants (porcine and bovine collagen matrices Strattice® and Veritas®) have been tested in experimental onlay hernia repair in rats in observation periods of 30 and 60 days. The key outcome parameters were mesh integration and reinforcement of the tissue at the implant site over sutured and sealed defects as well as comparison to native abdominal wall. Macroscopic assessment, biomechanical analysis and histology with haematoxylin/eosin staining, collagen staining and van Willebrand factor staining for detection of neovascularization were performed. RESULTS: BioA® was well integrated. Although the matrices were already fragmented at 60 days follow-up, hernia sites treated with synthetic scaffolds showed a significantly enhanced tissue deflection and resistance to burst force when compared to the native abdominal wall. In porcine and bovine matrices, tissue integration and shrinkage were significantly inferior to BioA®. Histology revealed a lack of fibroblast ingrowth through mesh interstices in biologic samples, whereas BioA® was tightly connected to the underlying tissue by reticular collagen fibres. CONCLUSIONS: Strattice® and Veritas® yielded reduced tissue integration and significant shrinkage, prohibiting further biomechanical tests. The synthetic BioA® provides little inherent strength but reticular collagen remodelling led to an augmentation of the scar due to significantly higher burst force resistance in comparison to native tissue.


Subject(s)
Hernia, Ventral/physiopathology , Herniorrhaphy/methods , Incisional Hernia/physiopathology , Surgical Mesh , Wound Healing/physiology , Abdominal Wall/surgery , Absorbable Implants , Animals , Biocompatible Materials/administration & dosage , Biological Products/administration & dosage , Cattle , Collagen/administration & dosage , Fibrin Tissue Adhesive , Hernia, Ventral/surgery , Incisional Hernia/surgery , Male , Rats , Rats, Sprague-Dawley , Swine , Tissue Scaffolds
18.
Surg Endosc ; 31(12): 4973-4980, 2017 12.
Article in English | MEDLINE | ID: mdl-27800586

ABSTRACT

BACKGROUND: Adhesion formation remains an important issue in hernia surgery. Liquid agents were developed for easy and versatile application, especially in laparoscopy. The aim of this study was to compare the antiadhesive effect of fibrin sealant (FS, Artiss®), Icodextrin (ID, Adept®) and Polyethylene glycol (PEG, CoSeal®) alone and in combination and to evaluate the resulting effect on tissue integration of the mesh. METHODS: A total of 56 Sprague-Dawley rats were operated in open IPOM technique. A middleweight polypropylene mesh of 2 × 2 cm size was implanted and covered with 1: FS, 2: ID, 3: PEG, 4: FS + ID, 5: FS + PEG, 6: PEG + ID, 7: control group, uncovered mesh (n = 8 per treatment/control). Observation period was 30 days. Macroscopic and histological evaluation was performed. RESULTS: Severe adhesions were found in group 2 (ID), group 6 (PEG + ID) and the controls. Best results were achieved with FS alone or FS + ID. Mesh integration in the treatment groups was reduced in comparison with the control group. This is a new finding possibly relevant for the outcome of intraperitoneal mesh repair. Group 6 (PEG + ID) showed an impairment of tissue integration with <50 % of the mesh surface in seven samples. CONCLUSION: FS alone and in combination with ID yielded excellent adhesion prevention. ID alone did not show significant adhesion prevention after 30 days. Tissue integration of FS-covered meshes was superior to ID or PEG alone or combined. PEG did show adhesion prevention comparable to FS but evoked impaired tissue integration. So Artiss® is among the most potent antiadhesive agents in IPOM repair.


Subject(s)
Hernia, Abdominal/surgery , Herniorrhaphy/methods , Postoperative Complications/prevention & control , Tissue Adhesions/prevention & control , Tissue Adhesives/therapeutic use , Animals , Fibrin Tissue Adhesive/therapeutic use , Glucans/therapeutic use , Glucose/therapeutic use , Herniorrhaphy/instrumentation , Icodextrin , Laparoscopy , Male , Polyethylene Glycols/therapeutic use , Random Allocation , Rats , Rats, Sprague-Dawley , Surgical Mesh , Tissue Adhesions/etiology , Treatment Outcome
19.
Cancer Treat Rev ; 47: 12-21, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27214603

ABSTRACT

BACKGROUND: The value of adjuvant radiotherapy in triple negative breast cancer (TNBC) remains unclear. A systematic review and meta-analysis was conducted in TNBC patients to assess survival and recurrence outcomes associated with radiotherapy following either breast conserving therapy (BCT) or post-mastectomy radiotherapy (PMRT). METHODS: Four electronic databases were searched from January 2000 to November 2015 (PubMed, MEDLINE, EMBASE and Web of Science). Studies investigating overall survival and/or recurrence in TNBC patients according to radiotherapy administration were included. A random effects meta-analysis was conducted using mastectomy only patients as the reference. RESULTS: Twelve studies were included. The pooled hazard ratio (HR) for locoregional recurrence comparing BCT and PMRT to mastectomy only was 0.61 (95% confidence interval [CI] 0.41-0.90) and 0.62 (95% CI 0.44-0.86), respectively. Adjuvant radiotherapy was not significantly associated with distant recurrence. The pooled HR for overall survival comparing BCT and PMRT to mastectomy only was 0.57 (95% CI 0.36-0.88) and HR 1.12 (95% CI 0.75, 1.69). Comparing PMRT to mastectomy only, tests for interaction were not significant for stage (p=0.98) or age at diagnosis (p=0.85). However, overall survival was improved in patients with late-stage disease (T3-4, N2-3) pooled HR 0.53 (95% CI 0.32-0.86), and women <40years, pooled HR 0.30 (95% CI 0.11-0.82). CONCLUSIONS: Adjuvant radiotherapy was associated with a significantly lower risk of locoregional recurrence in TNBC patients, irrespective of the type of surgery. While radiotherapy was not consistently associated with an overall survival gain, benefits may be obtained in women with late-stage disease and younger patients.


Subject(s)
Triple Negative Breast Neoplasms/mortality , Triple Negative Breast Neoplasms/radiotherapy , Female , Humans , Neoplasm Recurrence, Local/epidemiology , Neoplasm Recurrence, Local/prevention & control , Proportional Hazards Models , Radiotherapy, Adjuvant , Survival Analysis , Triple Negative Breast Neoplasms/surgery
20.
Int J Mycobacteriol ; 5 Suppl 1: S36-S37, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28043598

ABSTRACT

OBJECTIVE/BACKGROUND: Ethionamide (ETH) and isoniazid (INH) are part of the backbone regimen used for the treatment of multidrug-resistant tuberculosis (MDR-TB). Both ETH and INH are structurally similar and are activated by ethA and katG gene products. Resistance to INH among MDR-TB patients may cause ETH to be ineffective, as both target nicotinamide adenine dinucleotide-dependent enoyl-acyl carrier protein reductase inhA protein and mutations within inhA gene may lead to their cross-resistance. Furthermore, ETH resistance is caused by mutations within ethA and ethR genes forming part of the ETH drug activation pathway. Nicotinamide adenine dinucleotide is coded by the ndh gene, and its overexpresion may lead cross-resistance between INH and ETH drugs. Phenotypic drug susceptibility testing of ETH is difficult and often unreliable. We used whole genome sequencing to compare inhA, inhA promoter, ethA, ethR ndh, and katG genetic regions in serial isolates (baseline and follow-up) with treatment outcomes. METHODS: MDR-TB strains were collected from 46 patients before and during second-line drug treatment in KwaZulu-Natal and Eastern Cape between 2005 and 2009. All patients had phenotypically determined MDR-TB at baseline and had treatment outcomes documented. Unfavorable treatment outcomes were defined as death, default, and failure, while favorable outcomes were cure and treatment completion. Each strain had baseline and at least one strain collected on follow-up. From each strain, DNA was extracted from colonies grown on Löwenstein-Jensen slants, and fragment and jumping paired-end Illumina DNA libraries were constructed and sequenced on the Illumina HiSeq 2000 (Broad Institute, Cambridge, MA, USA). Sequences were aligned to H37Rv genome and Pilon was run to generate a list of SNPs. In silico spoligotyping was performed to a database 43 unique spacer sequences. Cross-resistance was defined as the presence of both inhA and either ethA or ethR mutations in clinical isolates. RESULTS: A total of 92 sequences from 46 serial isolates of MDR-TB patients from KwaZulu-Natal (29 isolates) and Eastern Cape (17 isolates) were analyzed. Most patients (29/46; 63.0%) had unfavorable outcomes, 13 (28.3%) had favorable outcomes, while four (8.7%) had unknown outcomes. Phylogenetic reconstruction revealed that primary genotype differed by province. The Beijing genotype was predominant in Eastern Cape, while EuroAmerican lineage (S, T, LAM, X) was found in KwaZulu-Natal. Whole genome analysis revealed nonsynonymous insertions and deletions within katG, ethA, ethR, ndh, and inhA and its promoter region. Among patients with treatment outcome data, mutations were detected in 92.8% in katG, 50% in inhA, 53.6% in ethA, 2.4% in ethR, and 19% in ndh. The majority of mutations causing ETH (20/29; 68.9%) and INH (18/29; 62.1%) resistance occurred among patients with unfavorable outcomes. Both inhA and either ethA or ethR mutations were detected in 16/29 (55.2%) patients with unfavorable outcomes. Cross-resistance of both INH and ETH drugs was associated with unfavorable treatment outcomes (p=0.021) in 16/29 (55.2%) patients compared with favorable treatment outcomes in 2/13 (15.4%) patients. CONCLUSION: Baseline ETH molecular resistance before second-line treatment is a concern. Unfavorable treatment outcomes of patients with ethA, ethR, and inhA mutations highlight the importance of genotypic testing before initiation of treatment containing ETH. The clinical significance of whole genome analysis for early detection of mutations predictive of treatment failure needs further investigation.

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