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1.
The results of femoral lengthening using the Italian modification of the Ilizarov are presented. Mean age of the patients was 14 years (ranging from 7 to 29). The most frequent etiology of limb shortening was femoral hypoplasia (7 patients) and sequelae of septic arthritis of the hip and/or the knee (6 patients). Indications for surgical treatment were limb shortening from 3 to 12 cm (mean 6.5 cm), along with axial deviation ranging from 10 degrees to 40 degrees in 6 patients. Mean follow-up time was 15 months (ranging from 6 to 35 months). The Ilizarov apparatus was based on two distal rings, stabilized by "K" wires, and proximally by a ring connected with an Italian femoral arch, stabilized by a Schanz screw. Planned lengthening (ranging from 3.5 cm to 12 cm) was achieved in all treated patients. The healing index ranged from 0.8 to 2.1 month/cm (mean 1.4). Problems, obstacles and complications were analyzed according to the Paley classification. In all 16 patients without primary knee stabilization, limited knee flexion ranging from 5 degrees to 90 degrees (mean 40 degrees) was noted during the distraction phase, which didn't improve significantly during the consolidation phase. Knee flexion improved to a mean 90 degrees after a 6 month follow-up. Bone regenerate defects (cysts, narrowing) were noted in 4 patients. Secondary knee stabilization was performed in 2 cases. In the first case because of knee pain and a severe limitation of knee motion. In the second, during a revision procedure because of distal femur angulation. Premature consolidation was noted in one patient and was treated by osteotomy. In one case axial deviation during the consolidation phase required osteotomy. In another case a fracture of the femur was treated by a plaster cast. In one case 1.5 years after the lengthening procedure subluxation of the hip was noted. Permanent knee flexion limitation to less than 90 degrees was noted in 6 patients. Femoral lengthening with the use of the Italian modification of the Ilizarov device give a high incidence of knee range of motion limitation, which can be decreased by preserving more than 30 degrees knee flexion during the distraction phase.  相似文献   
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IntroductionHigh smoking prevalence leads to increased morbidity and mortality in individuals with depression/anxiety. Integrated interventions targeting both smoking and mood have been found to be more effective than those targeting smoking alone, but the mechanisms of change of these interventions have not been investigated. This qualitative study aimed to understand participants'' experiences of the mechanisms underlying change in smoking behaviour following an integrated cognitive behavioural technique‐based intervention for smoking cessation and depression/anxiety.MethodsThis study was embedded within an ongoing randomized‐controlled acceptability and feasibility trial (http://www.isrctn.com/ISRCTN99531779). Semistructured interviews were conducted with 15 IAPT service users. Data were analysed using thematic analysis. During the interviews, participants were asked open‐ended questions about their quitting experience and perception of how the intervention aided their behaviour change.ResultsFive themes were identified. Acquiring an increased awareness of smoking patterns: participants described an increased understanding of how smoking was contributing towards their mental health difficulty. Developing individualized strategies: participants described acquiring ‘a couple of tricks up your sleeve’ that were helpful in making smoking cessation feel more ‘manageable’. Practitioner style as ‘supportive but not lecture‐y’: participants expressed how important the therapeutic alliance was in helping change their smoking behaviour. Importance of regular sessions: participants expressed the importance of ‘having someone that''s checking in on you’. Having the opportunity to access the intervention at ‘the right time’: participants described the intervention as the ‘push’ that they ‘needed’.ConclusionsParticipants identified key factors towards smoking behaviour change. Perceived increased awareness of how smoking negatively impacted participants'' mental health, and the opportunity to be offered smoking cessation treatment in a ‘non‐judgemental’, ‘supportive’ environment, with regular sessions and individualized strategies contributed to successful smoking cessation outcomes. If similar results are found in more diverse samples, these aspects should be embedded within integrated interventions for smoking cessation and depression/anxiety.Patient or Public ContributionPersons with lived experience of depression, anxiety and tobacco addiction contributed towards the design of the interview schedule, participant information sheets and the debriefing process. This was to ensure that interview questions were relevant, nonjudgemental and acceptable for those who did not manage to quit smoking.  相似文献   
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Viruses produce more viruses by manipulating the metabolic and replication systems of their host cells. Many have acquired metabolic genes from ancestral hosts and use the encoded enzymes to subvert host metabolism. The polyamine spermidine is required for bacteriophage and eukaryotic virus replication, and herein, we have identified and functionally characterized diverse phage- and virus-encoded polyamine metabolic enzymes and pathways. These include pyridoxal 5′-phosphate (PLP)-dependent ornithine decarboxylase (ODC), pyruvoyl-dependent ODC and arginine decarboxylase (ADC), arginase, S-adenosylmethionine decarboxylase (AdoMetDC/speD), spermidine synthase, homospermidine synthase, spermidine N-acetyltransferase, and N-acetylspermidine amidohydrolase. We identified homologs of the spermidine-modified translation factor eIF5a encoded by giant viruses of the Imitervirales. Although AdoMetDC/speD is prevalent among marine phages, some homologs have lost AdoMetDC activity and have evolved into pyruvoyl-dependent ADC or ODC. The pelagiphages that encode the pyruvoyl-dependent ADCs infect the abundant ocean bacterium Candidatus Pelagibacter ubique, which we have found encodes a PLP-dependent ODC homolog that has evolved into an ADC, indicating that infected cells would contain both PLP- and pyruvoyl-dependent ADCs. Complete or partial spermidine or homospermidine biosynthetic pathways are found encoded in the giant viruses of the Algavirales and Imitervirales, and in addition, some viruses of the Imitervirales can release spermidine from the inactive N-acetylspermidine. In contrast, diverse phages encode spermidine N-acetyltransferase that can sequester spermidine into its inactive N-acetyl form. Together, the virome-encoded enzymes and pathways for biosynthesis and release or biochemical sequestration of spermidine or its structural analog homospermidine consolidate and expand evidence supporting an important and global role of spermidine in virus biology.

The polyamine spermidine (Fig. 1) is a metabolically primordial polycation found throughout bacteria, archaea, and eukaryotes (1). It is a fundamental molecule of life that was likely present in the last universal common ancestor (2). In Escherichia coli, 90% of spermidine is noncovalently bound to RNA (3) and is required for efficient translational elongation by the ribosome (4). Spermidine increases global messenger RNA (mRNA) translation in E. coli by facilitating the queuosine modification of specific tRNA anticodon wobble bases (4). Consistent with these findings, in strains of E. coli deleted for genes that modify the anticodon wobble position in transfer RNAs (tRNAs), spermidine becomes absolutely essential for growth (5), which may be due to spermidine-mediated stabilization of the tRNA interaction with the translating ribosome. Spermidine is not only important for growth of bacteria; over 40 y ago, it was shown that T4 and T7 bacteriophages replicated more slowly in a spermidine-deficient mutant of E. coli (6). Replication of JG004 and N4-like phages in Pseudomonas aeruginosa PAO1 is absolutely dependent on spermidine (7, 8).Open in a separate windowFig. 1.Polyamine metabolic pathways. Pathways biochemically characterized herein are indicated by blue arrows and blue enzyme names.In eukaryotic cells, spermidine is universally required for growth and cell proliferation. An aminobutyl moiety of spermidine (Fig. 1) is transferred by deoxyhypusine synthase (DHS) to a single lysine of the translation factor eIF5A to eventually form the essential hypusine posttranslational modification (9). Hypusinated eIF5a is needed for translation of mRNAs encoding proline-rich motifs and for translation termination (10). Replication of eukaryotic RNA viruses is highly dependent on host spermidine (11), and spermidine-derived hypusination of host eIF5a is required for Ebola virus replication and is considered a potential target to inhibit viral replication (12).Viruses reprogram the metabolism of host cells to make more virions by redirecting expression and activity of host-encoded enzymes and by expressing virus-encoded enzymes. Using homology-based approaches, nucleocytoplasmic large DNA viruses have been found to encode homologs of enzymes involved in nitrogen metabolism, glycolysis, and the tricarboxylic acid cycle (13). Bacteriophages have been found to encode homologs of enzymes involved in inorganic sulfur metabolism (14) and nucleotide metabolism (15). The eukaryotic chlorovirus Paramecium bursaria chlorella virus 1 (PBCV-1) encodes an entire functional biosynthetic pathway for production of homospermidine (Fig. 1), a structural analog of spermidine, consisting of L-arginine decarboxylase (ADC), agmatine deiminase/iminohydrolase (AIH), N-carbamoylputrescine amidohydrolase (NCPAH), and homospermidine synthase (HSS) (1618). In addition, PBCV-1 encodes a polyamine N-acetyltransferase (19). A biochemically functional HSS enzyme is encoded by Ralstonia phage ϕRSL1 (20). Considering the importance of polyamines to phage and virus replication, we sought to systematically identify and functionally characterize polyamine metabolic enzymes and pathways encoded in phage and virus genomes. Some of the taxonomic affiliations of giant viruses included in our study are based on a recently published hierarchical taxonomy for the Nucleocytoviricota (21).  相似文献   
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A case of osteomyelitis in an infant following a burn injury sustained in Pakistan caused by a GES-13-producing Pseudomonas aeruginosa (the first reported in Canada) and an OXA-48 producing Klebsiella pneumoniae is described. The present case serves to highlight the importance of international travel as a risk factor for infection with carbapenemase-producing bacteria and the challenges in the laboratory detection of these organisms.  相似文献   
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Background

Measurement of the common bile duct (CBD) is considered a fundamental component of biliary point-of-care ultrasound (POCUS), but can be technically challenging.

Objective

The primary objective of this study was to determine whether CBD diameter contributes to the diagnosis of complicated biliary pathology in emergency department (ED) patients with normal laboratory values and no abnormal biliary POCUS findings aside from cholelithiasis.

Methods

We performed a prospective, observational study of adult ED patients undergoing POCUS of the right upper quadrant (RUQ) and serum laboratory studies for suspected biliary pathology. The primary outcome was complicated biliary pathology occurring in the setting of normal laboratory values and a POCUS demonstrating the absence of gallbladder wall thickening (GWT), pericholecystic fluid (PCF) and sonographic Murphy's sign (SMS). The association between CBD dilation and complicated biliary pathology was assessed using logistic regression to control for other factors, including laboratory findings, cholelithiasis and other sonographic abnormalities.

Results

A total of 158 patients were included in the study. 76 (48.1%) received non-biliary diagnoses and 82 (51.9%) were diagnosed with biliary pathology. Complicated biliary pathology was diagnosed in 39 patients. Sensitivity of CBD dilation for complicated biliary pathology was 23.7% and specificity was 77.9%.

Conclusion

Of patients diagnosed with biliary pathology, none had isolated CBD dilatation. In the absence of abnormal laboratory values and GWT, PCF or SMS on POCUS, obtaining a CBD measurement is unlikely to contribute to the evaluation of this patient population.  相似文献   
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Cocaine-associated myocardial infarction (CAMI) is a well-reported entity. Most previous reports on CAMI have been limited to conservative care utilizing benzodiazepines, aspirin, nitroglycerin, calcium channel blockers, and thrombolytics. Current guidelines on CAMI advocate immediate use of angiography and angioplasty if available rather than routine administration of thrombolytics. However, based on literature search from 1966 to 2001 (using keywords "cocaine," "myocardial infarction," and "angioplasty"), there have been only two case reports of percutaneous coronary intervention (PCI) in patients with cocaine-associated myocardial infarction. Both were notable for complications either during or immediately after the procedure. We report a series of 10 patients with cocaine-associated myocardial infarction who were treated with percutaneous interventions, which included angioplasty, stenting, and AngioJet mechanical extraction of thrombus. Despite the different arteriopathic process involved, our findings suggest that PCI can be performed safely and with a high degree of procedural success in patients with CAMI.  相似文献   
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ObjectivesSystemic inflammatory response syndrome (SIRS) and hematoma expansion are independently associated with worse outcomes after intracerebral hemorrhage (ICH), but the relationship between SIRS and hematoma expansion remains unclear.Materials and methodsWe performed a retrospective review of patients admitted to our hospital from 2013 to 2020 with primary spontaneous ICH with at least two head CTs within the first 24 hours. The relationship between SIRS and hematoma expansion, defined as ≥6 mL or ≥33% growth between the first and second scan, was assessed using univariable and multivariable regression analysis. We assessed the relationship of hematoma expansion and SIRS on discharge mRS using mediation analysis.ResultsOf 149 patients with ICH, 83 (56%; mean age 67±16; 41% female) met inclusion criteria. Of those, 44 (53%) had SIRS. Admission systolic blood pressure (SBP), temperature, antiplatelet use, platelet count, initial hematoma volume and rates of infection did not differ between groups (all p>0.05). Hematoma expansion occurred in 15/83 (18%) patients, 12 (80%) of whom also had SIRS. SIRS was significantly associated with hematoma expansion (OR 4.5, 95% CI 1.16 - 17.39, p= 0.02) on univariable analysis. The association remained statistically significant after adjusting for admission SBP and initial hematoma volume (OR 5.72, 95% CI 1.40 – 23.41, p= 0.02). There was a significant indirect effect of SIRS on discharge mRS through hematoma expansion. A significantly greater percentage of patients with SIRS had mRS 4-6 at discharge (59 vs 33%, p=0.02).ConclusionSIRS is associated with hematoma expansion of ICH within the first 24 hours, and hematoma expansion mediates the effect of SIRS on poor outcome.  相似文献   
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