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Aim To assess our personal experience of a case of tuberculosis of the talus, and to provide an overview of the literature about the tuberculosis manifestations, including all its aspects: epidemiology, clinical and imaging presentation, and all the treatments available to the current state of knowledge. Methods We present our experience in a case of a 34-year-old patient, who came to our attention with difficulty in walking and pain due to a talar tuberculosis, with consequent bone disruption and reabsorption, and foot deformities. Results A tibiotalocalcaneal arthrodesis with retrograde nail and bone graft was performed after antibiotic therapy. Today, almost two years after the treatment, the patient can walk independently with no major limitations in everyday life. Conclusion Tibiotalocalcaneal arthrodesis with bone graft showed good functional results in this case study, with complete graft fusion and good functional and radiological outcomes.
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Prosthetic instability is one of the most challenging complications to manage when considering reverse shoulder arthroplasty (RSA). Additional tools are available to improve accuracy in planning and execution of arthroplasties, such as 3-dimensional (3D) virtual planning based on computer tomography (CT) scan and intra-operative navigation. We report a case of an 84-year-old male treated for RSA prosthetic instability combined with severe glenoid deformity and bone loss, and subclinical periprosthetic joint infection (PJI). The definitive surgery consisted in implanting a customized metaglene component realized on the basis of the bone defect detected in the 3D-CT scan and implanted with the aid of computer-assisted intra-operative navigation. The patient was periodically followed-up for a year with clinical and radiological evaluations with the absence of further prosthetic dislocations nor PJI, a good overall satisfaction, a satisfying range of motion, and acceptable functional scores (American Shoulder and Elbow Surgeons Score 62, Constant-Murley Score 36). This is the first description, to our knowledge, of a customized glenoid baseplate implanted with the aid of intraoperative navigation. The combined use of 3D-CT planning and intra-operative computer-assisted navigation allows to manage complex cases of prosthetic revision surgery even where extensive bone defects are present.
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Joint dysplasias always represent a great challenge for prosthetic surgeons. The common altered anatomical landmarks and the subversion of the anatomy of soft tissues surrounding the dysplastic joint are problems that can cause difficulties if approached with standard methods. Together with the resolution of functional issues related to dysplasia, the understanding of the underlying cause is fundamental. DNA analysis is generally performed via blood sampling; however, this might lead to misdiagnosis in case mosaicism is not detected in blood components. The etiology of genetic diseases can be further examined by means of whole exome sequencing and the detection of somatic mosaicism, recognized as a fundamental contributor to genetic diseases themselves. In this study, the clinical case of a patient suffering from a rare unilateral dysplasia localized to the left coxo-femoral and glenohumeral joint and treated at our center for reverse shoulder arthroplasty is reported. By virtue of the glenohumeral anatomical peculiarities, we had to devise a hybrid custom-made and navigated approach by means of a custom-made prosthetic stem and dedicated patient-specific instrumentation, using intraoperative GPS navigation for glenoid prosthesis. In addition, a genetic study was conducted on intraoperatively harvested bone marrow, which proved to be crucial in understanding the epigenetic basis of dysplasia. In fact, the patient resulted negative in blood but positive for a truncating variant of PTEN c.781C > T (p.(Gln261 *)) in 12% of the sequence analyzed in the bone marrow.
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Tomato leaf curl New Delhi virus (ToLCNDV), a bipartite Begomovirus belonging to the family Geminiviridae, causes severe damage to many economically important crops worldwide. In the present study, pathogenicity of Asian (ToLCNDV-In from Pakistan) and Mediterranean isolates (ToLCNDV-ES from Italy) were examined using infectious clones in tomato plants. Only ToLCNDV-In could infect the three tomato cultivars, whereas ToLCNDV-ES could not. Genome-exchange of the two ToLCNDVs revealed the ToLCNDV DNA-A segment as the main factor for ToLCNDV infectivity in tomato. In addition, serial clones with chimeric ToLCNDV-In A and ToLCNDV-ES A genome segments were generated to identify the region determining viral infectivity in tomatoes. A chimeric clone carrying the ToLCNDV-In coat protein (CP) exhibited pathogenic adaptation in tomatoes, indicating that the CP of ToLCNDV is essential for its infectivity. Analyses of infectious clones carrying a single amino acid substitution revealed that amino acid at position 143 of the CP is critical for ToLCNDV infectivity in tomatoes. To better understand the molecular basis whereby CP function in pathogenicity, a yeast two-hybrid screen of a tomato cDNA library was performed using CPs as bait. The hybrid results showed different interactions between the two CPs and Ring finger protein 44-like in the tomato genome. The relative expression levels of upstream and downstream genes and Ring finger 44-like genes were measured using quantitative reverse transcription PCR (RT-qPCR) and compared to those of control plants. This is the first study to compare the biological features of the two ToLCNDV strains related to viral pathogenicity in the same host plant. Our results provide a foundation for elucidating the molecular mechanisms underlying ToLCNDV infection in tomatoes.
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BACKGROUND: Complex proximal humeral fractures (cPHFs) represent an important public health concern, and reverse shoulder arthroplasty (RSA) has emerged as a feasible treatment option in the elderly with high functional demands. Recent studies have shown that tuberosity healing leads to better clinical outcomes and an improved range of motion. However, the best surgical technique for the management of the tuberosities is still a topic of debate. The purpose of this retrospective observational study is to report the radiographic and clinical outcomes of a consecutive series of patients who underwent RSA for cPHFs using a novel "7 sutures and 8 knots" technique. MATERIALS AND METHODS: A consecutive series of 32 patients (33 shoulders) were treated with this technique by a single surgeon from January 2017 to September 2021. Results at a minimum follow-up of 12 months and a mean ± SD follow-up of 35.9 ± 16.2 (range 12-64) months are reported. RESULTS: The tuberosity union rate was 87.9% (29 out of 33 shoulders), the mean Constant score was 66.7 ± 20.5 (range 29-100) points, and the mean DASH score was 33.4 ± 22.6 (range 2-85) points. CONCLUSIONS: The "7 sutures and 8 knots" technique, which relies on three sutures around the implant and five bridging sutures between the tuberosities, is a relatively simple procedure which provides a reliable means for anatomic restoration of the tuberosities and allows functional recovery of the shoulder in elderly patients with cPHFs treated with RSA. LEVEL OF EVIDENCE: IV; retrospective atudy. TRIAL REGISTRATION: At our institution, no institutional review board nor ethical committee approval is necessary for retrospective studies.
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Artroplastía de Reemplazo de Hombro , Fracturas del Hombro , Articulación del Hombro , Humanos , Anciano , Artroplastía de Reemplazo de Hombro/métodos , Estudios Retrospectivos , Resultado del Tratamiento , Curación de Fractura , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Suturas , Rango del Movimiento Articular , Articulación del Hombro/cirugíaRESUMEN
Introduction: The COVID-19 pandemic has affected and is still deeply affecting all aspects of public life. World governments have been forced to enact restrictive measures to stem the contagion which have led to a decrease in the movement of people within national territory and to a redirection of health care resources with a suspension of non-urgent procedures. In Italy, a lockdown was imposed from March 9th to May 3rd, 2020. As a result, a significant reduction in the overall operative volume of orthopedic trauma was expected, but it was not possible to predict a similar trend regarding fragility fractures of the proximal femur in the elderly. Methods: The aim of this paper was to examine the impact of COVID-19 on the operating volume for trauma surgeries and to determine how the pandemic affected the management of fragility hip fractures (FHFs) in non-COVID patients at a single Institution. Results: The first result was a statistically significant reduction in the overall operative volume of orthopedic trauma during the period of the first lockdown and an increase in the mean age of patients undergoing surgery, as expected. As regard to the second aim, the incidence of FHFs remained almost unchanged during the periods analysed. The population examined were superimposable in terms of demographics, comorbidities, type of fracture, peri-operative complications, percentage of operations performed within 48 hours from hospitalization and 1-year outcome. Discussion: Our results are in line with those already present in the Literature. Conclusions: Our study revealed a significant impact of the restrictive anti-contagion measures on the overall orthopedic surgical volume, but, at the same time, we could affirm that the pandemic did not affect the management of FHFs in non-COVID patients, and their results.
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BACKGROUND: Delayed bone healing and nonunions represent a great challenge for the orthopedic surgeon. In addition to traditional surgical approaches, increasing attention is being given to the use of systemic anabolic therapy with Teriparatide, whose efficacy in preventing osteoporotic fractures is widely validated and whose application as a promoter of bone healing has been described but it is still debated. The aim of the study was to evaluate bone healing in a series of patients with delayed unions or nonunions treated with Teriparatide in conjunction with eventual appropriate surgical procedure. METHODS: Twenty patients with an unconsolidated fracture that were treated at our Institutions from 2011 to 2020 with Teriparatide were retrospectively included into the study. The pharmacological anabolic support was used off-label with a planned duration of 6 months; radiographic healing was evaluated at 1-, 3- and 6-months follow-up outpatient visits over plain radiographs. Also, eventual side-effects were registered. RESULTS: Radiographic signs indicative of favorable evolution of the bone callus were observed as early as at 1 month of therapy in 15% of cases; at 3 months, healing progression was appreciated in 80% of cases and complete healing in 10%; at 6 months, 85% of delayed and nonunions had healed. In all patients, the anabolic therapy was well tolerated. CONCLUSIONS: In accordance to Literature, this study suggests that Teriparatide plays a potentially important role in the treatment of some forms of delayed unions or nou-nions, even in the presence of failure of hardware. The results suggest a greater effect of the drug when associated with a condition in which the bone is in an active phase of callogenesis, or with a "revitalizing" treatment which represents a local (mechanical and/or biological) stimulus to the healing process. Despite the small sample size and the variety of cases, the efficacy of Teriparatide in treating delayed unions or nonunions emerged, highlighting how this anabolic therapy can represent a useful pharmacological support in the treatment of such a pathology. Although the results obtained are encouraging, further studies, particularly prospective and randomized, are needed to confirm the efficacy of the drug, and define a specific treatment algorithm.
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Conservadores de la Densidad Ósea , Fracturas Osteoporóticas , Humanos , Teriparatido/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Estudios Prospectivos , Estudios Retrospectivos , Curación de Fractura , Fracturas Osteoporóticas/tratamiento farmacológico , Resultado del TratamientoRESUMEN
Tomato leaf curl New Delhi virus-ES (ToLCNDV-ES), a high threat to cucurbits in the Mediterranean Basin, is listed as a different strain from the Asian ToLCNDV isolates. In this study, the infectivity of two clones previously isolated from Italy and Pakistan were compared in cucumbers, which resulted in the opposite symptom appearance. The swapping subgenome was processed; however, the mechanisms related to the disease phenotype remain unclear. To identify the disease-associated genes that could contribute to symptom development under the two ToLCNDV infections, the transcriptomes of ToLCNDV-infected and mock-inoculated cucumber plants were compared 21 days postinoculation. The number of differentially expressed genes in ToLCNDV-India-infected plants was 10 times higher than in ToLCNDV-ES-infected samples. The gene ontology (GO) and pathway enrichment were analyzed using the Cucurbits Genomics Database. The flavonoid pathway-related genes were upregulated in ToLCNDV-ES, but some were downregulated in ToLCNDV-India infection, suggesting their role in resistance to the two ToLCNDV infections. The relative expression levels of the selected candidate genes were validated by qRT-PCR under two ToLCNDV-infected conditions. Our results reveal the different infectivity of the two ToLCNDVs in cucumber and also provide primary information based on RNA-seq for further analysis related to different ToLCNDV infections.
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Begomovirus , Cucumis sativus , Cucumis sativus/genética , Reacción en Cadena de la Polimerasa , India , Pakistán , Italia , Begomovirus/genética , Enfermedades de las Plantas/genéticaRESUMEN
Charcot Foot (CF), part of a broader condition known as Charcot Neuro-Osteoarthropathy (CNO), is characterized by neuropathic arthropathy with a progressive alteration of the foot. CNO is one of the most devastating complications in patients with diabetes mellitus and peripheral neuropathy but can also be caused by neurological or infectious diseases. The pathogenesis is multifactorial; many studies have demonstrated the central role of inflammation and the Receptor Activator of NF-κB ligand (RANKL)-Receptor Activator of NF-κB (RANK)-Osteoprotegerin (OPG) pathway in the acute phase of the disease, resulting in the serum overexpression of RANKL. This overexpression and activation of this signal lead to increased osteoclast activity and osteolysis, which is a prelude to bone destruction. The aim of this narrative review is to analyze this signaling pathway in bone remodeling, and in CF in particular, to highlight its clinical aspects and possible therapeutic implications of targeting drugs at different levels of the pathway. Drugs that act at different levels in this pathway are anti-RANKL monoclonal antibodies (Denosumab), bisphosphonates (BP), and calcitonin. The literature review showed encouraging data on treatment with Denosumab, although in a few studies and in small sample sizes. In contrast, BPs have been re-evaluated in recent years in relation to the high possibility of side effects, while calcitonin has shown little efficacy on CNO.
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Conservadores de la Densidad Ósea , Diabetes Mellitus , Pie Diabético , Osteólisis , Humanos , Osteoprotegerina/metabolismo , Pie Diabético/tratamiento farmacológico , Pie Diabético/etiología , Receptor Activador del Factor Nuclear kappa-B , Calcitonina , Denosumab , Conservadores de la Densidad Ósea/uso terapéutico , FN-kappa B , Ligando RANK/metabolismoRESUMEN
Introduction. The ever-expanding indications for total hip arthroplasty are leading to more implants being placed in younger as well as in older patients with high functional demand. Also, prolonged life expectancy is contributing to an overall increment of periprosthetic femoral fractures. The Vancouver classification has been the most used for guiding the surgeon choice since its proposal in 1995. Fractures occurring over a hip femoral implant can be divided into intra-operative and post-operative PFFs, and their treatment depends on factors that may severely affect the outcome: level of fracture, implant stability, quality of bone stock, patients' functional demand, age and comorbidities, and surgeon expertise. There are many different treatment techniques available which include osteosynthesis and revision surgery or a combination of both. The goals of surgical treatment are patients' early mobilization, restoration of anatomical alignment and length with a stable prosthesis and maintenance of bone stock. Significance. The aim of this review is to describe the state-of-the-art treatment and outcomes in the management of PFFs. We performed a systematic literature review of studies reporting on the management of PFFs around hip stems and inter-prosthetic fractures identifying 45 manuscripts eligible for the analysis. Conclusions. PFFs present peculiar characteristic that must be considered and special features that must be addressed. Their management is complex due to the extreme variability of stem designs, the possibility of having cemented or uncemented stems, the difficulty in identifying the "real" level of the fracture and the actual stability of the stem. As a result, the definition of a standardized treatment is unlikely, thereby high expertise is fundamental for the surgical management of PPFs, so this kind of fractures should be treated only in specialized centres with both high volume of revision joint arthroplasty and trauma surgery.
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In this study, a new virus was identified in French hydrangea plants, exhibiting chlorotic vein banding and necrotic ring spots on older leaves. The virus was mechanically transmitted to herbaceous hosts, in which it induced local and systemic or only local symptoms. The genome of the new virus was characterized and consisted of three RNA sequences that were 3422 (RNA 1), 2905 (RNA 2) and 2299 (RNA 3) nucleotides long, with five predicted open reading frames; RNA2 was bicistronic and contained conserved domains and motifs typical of ilarviruses. The phylogenetic analysis of the predicted proteins-p1, p2a, p3a and p3b-revealed its close relationship to recognized members of subgroup 2 within the genus Ilarvirus. Homologous antiserum was effective in the detection of the virus in plant extracts and no cross reactions with two other distinct members of subgroup 2 were observed. Overall, the biological features, phylogenetic relationships and serological data suggest that this virus is a new member of the genus, for which we propose the name hydrangea vein banding virus (HdVBV).
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Introduction: An increasing number of patients is annually undergoing total hip arthroplasty (THA), and a significant proportion of these patients are elderly and consequently at a higher risk of complications because of age, osteoporosis, and medical comorbidities. Periprosthetic femoral fractures (PFFs) are one of the worst complications of THA associated with high rates of unfavorable prognosis. Besides, in the last decade, a new independent disease entity called "atypical femoral fracture" (AFF) has been identified and defined by the American Society for Bone and Mineral Research (ASBMR) task force. Some PFFs present clinical history and radiographic aspect consistent with an AFF, meeting the ASBMR criteria for the diagnosis of AFF except that PFFs by themselves are an exclusion criterion for AFF. However, there is an increasing number of published studies suggesting that periprosthetic atypical femoral fractures (PAFFs) exist and should not be excluded by definition. Significance: Nowadays, although there is an increasing interest in PAFFs, there are still very few studies published on the topic and a lack of consensus regarding their treatment. This narrative literature review aims to introduce this new emerging topic to a wider readership describing the characteristics of PAFFs and the state-of-the-art in their management. Conclusions: Many authors agree that PAFFs should be considered as a subgroup of PFFs that have atypical characteristics; they also show a significant correlation with prolonged bisphosphonate use. A correct diagnosis is paramount for proper treatment of the disease that requires both surgical and medical actions to be taken.
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Tomato leaf curl New Delhi virus (ToLCNDV) became an alerting virus in Europe from 2017 to 2020 because of its significant damage to Cucurbitaceae cultivation. Until now, just some cucurbit crops including sponge gourd, melon, pumpkin, and cucumber were reported to be resistant to ToLCNDV, but no commercial cultivars are available. In this study, a new isolate of ToLCNDV was identified in Pakistan and analyzed together with ToLCNDV-ES which was previously isolated in Italy. Furthermore, infectious clones of two ToLCNDV isolates were constructed and agroinoculated into different cucurbit crops to verify their infectivity. Results showed that both isolates exhibited severe infection on all tested cucurbit (>70%) except watermelon. Thus, those cultivars may be good candidates in the first step of screening genetic resources for resistance on both Southeast Asian and Mediterranean ToLCNDV isolates. Additional, comparison pathogenicity of different geographical ToLCNDV isolates will be aided to understand viral characterization as such knowledge could facilitate breeding resistance to this virus.
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Bemisia tabaci is a key pest of horticultural, fibre and ornamental crops worldwide, primarily as a vector of plant viruses. In Italy, B. tabaci has established since the 1980s-1990s in southern regions as well as in Sicily and Sardinia. Recent reports of infestations in some areas of central Italy prompted a new survey to assess the whitefly distribution in the country as well as to update the species and haplotype composition of the populations present in southern Italy and in the main islands. The survey confirmed that B. tabaci is nowadays established in central Italy even at more northern latitudes than those noticed before. Most of the specimens collected throughout the country belonged to the Mediterranean (MED) species. The MEDQ1 and Q2 haplogroups were prevailing in open-field and greenhouse cultivations, respectively, except in Sardinia where only Q1 specimens were found on a wide range of crops and weeds. Population genetics analyses showed that several MEDQ1 haplotypes currently occur in Italy and their distribution is unrelated to evident temporal and geographic trends, except for a new genetic variant which seems to have originated in Sardinia. The MED species is known to better adapt to insecticide treatments and high temperatures, and its northward spread in Italy may have been favoured by the intensive agricultural practices and steady increase in both winter and summer temperatures occurring in the last few decades. The extensive presence of B. tabaci in Italy proves that a strict surveillance for possible new outbreaks of whitefly-transmitted viruses should be addressed to a range of sites that are expanding northwards.
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BACKGROUND: Some periprosthetic femoral fractures (PFFs) present history and radiographic aspect consistent with an atypical femoral fracture (AFF), fulfilling the criteria for AFF except that PFFs by themselves are excluded from the diagnosis of AFFs. The aim of this study is to evaluate in a single institution series of PFFs if any of them could be considered a periprosthetic atypical femoral fracture (PAFF), and their prevalence. METHODS: Surgical records were searched for PFFs around a primary hip stem from January 2013 to December 2019. Cases were classified according to Vancouver classification. Demographic and medical history was extracted. Fisher's exact test was used for statistical analysis. RESULTS: One hundred fifteen PFFs were identified, 59 of them were type B1 and 16 were type C. Radiographs and medical records were available for all patients. Twenty-four patients (32%) have been treated with bisphosphonates (BPs) for longer than 4 years. Four patients presented a fracture with characteristics of PAFF. When enlarged to all PFFs of the series, no other PAFF was found: prevalence of PAFFs was 5.3% for type B1 and C cases and 3.5% for all surgically treated PFFs. Statistical significative difference between PAFFs and PFFs was found for prolonged BP assumption and for the level of fracture clear of the stem. CONCLUSION: Fracture with characteristics of AFFs can also happen over a prosthetic stem, configuring themselves as PAFFs, and they are related to prolonged BP use. As a correct diagnosis is mandatory for proper treatment, a revision of criteria for AFFs should be considered, accepting that PAFFs exist.
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Artroplastia de Reemplazo de Cadera , Fracturas del Fémur , Fracturas Periprotésicas , Artroplastia de Reemplazo de Cadera/efectos adversos , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/epidemiología , Fracturas del Fémur/etiología , Humanos , Fracturas Periprotésicas/diagnóstico por imagen , Fracturas Periprotésicas/epidemiología , Fracturas Periprotésicas/etiología , Prevalencia , Reoperación , Estudios RetrospectivosRESUMEN
Aim To evaluate the efficacy of systemic plus local tranexamic acid (TXA) in reducing post-operative bleeding, haemoglobin loss and the need for allogeneic blood transfusion (ABT) in total knee arthroplasty (TKA). Methods All patients undergoing TKA between January 2017 and September 2019 were retrospectively evaluated. Exclusion criteria were cardiovascular comorbidities, diabetes and the assumption of any anticoagulant/antiaggregant therapy in the pre-operative period. All patients received the same prosthesis with the same surgical technique and were operated on by the same surgeon. Twenty patients were found (group A) that received intra-operative TXA (20 mg/kg intravenous 10 minutes before deflating tourniquet and 1g intra-articular after capsular suture). A control group of 26 patients not receiving TXA was matched for demographics (group B). Results Two (10%) patients in group A and 16 (61.5%) in group B needed ABT in the post-operative period (p=0.0004). Each patient in group A received 2 red blood cells (RBCs) units, while in group B 2 patients received one RBCs unit and one patient 4 RBCs units, for a total of 4 and 32 RBCs units in group A and B, respectively (p=0.0006). The minimum haemoglobin level was observed at 48 hours post-operatively in both groups: mean decrease was 3.54 and 4.64 g/dL in group A and B, respectively (p=0.0126). Conclusion The association of systemic and local TXA administration seems to significantly reduce post-operative bleeding and the need for RBCs transfusions after TKA in patients not assuming any anticoagulant / antiaggregant therapy and without cardiovascular and diabetic morbidities.
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Antifibrinolíticos , Artroplastia de Reemplazo de Rodilla , Trasplante de Células Madre Hematopoyéticas , Ácido Tranexámico , Antifibrinolíticos/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Transfusión Sanguínea , Humanos , Estudios Retrospectivos , Ácido Tranexámico/uso terapéuticoRESUMEN
INTRODUCTION: There is lack of consensus regarding best operative fixation strategy for periprosthetic femoral fractures (PFFs) around a stable stem. Evidence exists that some patterns of fracture around a stable stem are better treated with revision surgery than with standard fixation. Anyway, a more aggressive surgical procedure together with medical treatment could allow for stem retention, and reduced risk of nonunion/hardware failure, even in these cases. SIGNIFICANCE: This paper is placed in a broader context of lack of studies on the matter, and its aim is to shed some light on the management of PFFs around a stable stem, when peculiar mechanical and biological aspects are present. RESULTS: Based on our casuistry in the treatment of nonunions after PFF successfully treated with original stem retention, and on review of Literature about risk factors for fixation failure, an algorithm is proposed that can guide in choosing the ideal surgical technique even for first-time PFFs with a stable stem, without resorting to revision. Mechanical (major and minor) and biological (local and systemic) factors that may influence fracture healing, leading to nonunion and hardware failure, and subsequent need for re-operation, are considered. The proposed surgical technique consists of rigid fixation with absolute stability (using a plate and structural allograft) plus local biological support (structural allograft and autologous bone marrow concentrate over a platelet-rich plasma-based scaffold) at fracture site. Systemic anabolic treatment (Teriparatide) is also administered in the post-operative period. CONCLUSION: Mechanical factors are not the only issues to be considered when choosing the surgical approach to PFFs over a stable stem. Systemic and local biological conditions should be taken into account, as well. A therapeutic algorithm is proposed, given the prosthetic stem to be stable, considering mechanical and biological criteria.
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Chayote (Sechium edule (Jacq.) Sw.) is a vigorous perennial and climbing cucurbits, native to Mesoamerica, and cultivated for alimentary purposes in the American continent, Australia, New Zealand, South Europe, Asia and Africa. During spring 2019, some chayote plants showing bright yellow vein banding rings and lines were observed in a private garden in South Italy (Campania region). Symptoms coalesced in some leaves, covering almost the whole foliar area. Double-stranded RNAs were extracted from symptomatic leaves of a single chayote plant and reverse-transcribed, randomly amplified, and submitted to Illumina sequencing (Marais et al., 2018). Reads were assembled using CLC Genomics Workbench 11.1 (http://www.clcbio.com). Contigs were then annotated by Blastn and Blastx comparison with the Genbank database, which allowed the identification of eight contigs of between 380 and 980 nucleotides sharing significant identity with alfalfa mosaic virus (AMV) genomic RNAs. No other viral contigs were identified. Mapping of reads on AMV genomic RNAs identified 4,209 AMV reads (1.26% of total reads) and allowed the scaffolding of the contigs into three scaffolds corresponding to the three AMV genomic RNAs. To complete the sequence of the AMV chayote isolate genome (named See-1), primers were designed from the contig sequences and used to amplify RACE PCR products spanning the 5' and 3' terminal regions of the three genomic RNAs using the SMARTer™ RACE cDNA Amplification Kit (Clontech, China). All amplicons were cloned into the pGEM-T vector (Promega, USA) and sequenced (three clones for each amplicon) by Microsynth Seqlab (Microsynth AG, Switzerland). Finally, the complete genomic sequences of the three RNAs were assembled by MacVector 17.5 (MacVector Inc., USA). The RNA1, RNA2 and RNA3 of See-1 are 3,643, 2,593 and 2,037 nt respectively (GenBank accession Nos. MT093209 to MT093211), and share the highest nt sequence identity with the RNA1 and RNA3 of AMV isolate (HZ) from tobacco (99.5% for RNA1, HQ316635; 98.7% for RNA3, HQ316637) and with the RNA2 of isolate AMV-Gym from Gynostemma pentaphyllum (98.1%, MH332898), both from China. AMV isolate See-1 was classified as belonging to subgroup I based on the presence of a BamH I and two AvaII sites in the CP ORF (Parrella et al., 2000). Reverse transcription polymerase chain reaction, using primers targeting the CP gene (Parrella et al., 2000), confirmed AMV infection in three symptomatic cayote plants including that used for Illumina sequencing, with 100% of nt sequence identity of amplicons. Three plants each of Chenopodium amaranticolor, Nicotiana benthamiana and Solanum lycopersicon were mechanically inoculated with sap from isolate See-1 infected plant, leading to the appearance of typical AMV symptoms in all three hosts ten days post-inoculation (Jaspars & Bos, 1980). This note describes the first detection of AMV in cayote in Italy and, to the best of our knowledge, in the world. In some areas of Southern Italy, climatic conditions are favorable enough to allow chayote development in the wild. Further studies would be desirable to determine the distribution and incidence of AMV in chayote and to understand the possibility that this species may play a role in AMV epidemiology, representing a threat to other susceptible crops.
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Tomato leaf curl New Delhi virus (ToLCNDV) is a bipartite begomovirus affecting tomato cultivation on the Indian subcontinent. Recently, however, a new strain of the virus, named ToLCNDV-ES, has spread to Mediterranean countries such as Spain, Italy, and Tunisia, and occurred in Cucurbita crops, causing economic damage. Although ToLCNDV is spread by the sweet potato whitefly (Bemisia tabaci), like other begomoviruses, it has not been clear how ToLCNDV suddenly spread from the Indian subcontinent to the Mediterranean region. In 2017, ToLCNDV was diagnosed in young seedlings germinated naturally from fruits fallen in the prior year on a farm located in Giugliano in Campania, Naples, Italy, suggesting a possible role of the seeds in vertical transmission of the virus. Because sweet potato whiteflies were widespread naturally in that region, it was necessary to verify that in an artificial insect vector-free condition. Seeds were harvested from two ToLCNDV-infected zucchini squash cultivars in Naples in 2017 and 2018 to examine whether ToLCNDV can be transmitted from zucchini squash seeds to young plants. Viral DNA was amplified from these seeds and 1- to 3-week-old seedlings germinated from them with a ToLCNDV-specific primer set. According to PCR results, viral contamination was confirmed from all harvested seeds and dissemination was proven from 61.36% of tested seedling samples. Mechanical transmission from seed-borne virus-infected seedlings to healthy zucchini squash plants was also succesful, demonstrating that seedlings from ToLCNDV-infected seeds did act as inoculum. This is the first report demonstrating that ToLCNDV is a seed-transmissible virus in zucchini squash plants in Italy.