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1.
Mol Phylogenet Evol ; 193: 107997, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38128795

RESUMEN

Madagascar exhibits extraordinarily high level of species richness and endemism, while being severely threatened by habitat loss and fragmentation (HL&F). In front of these threats to biodiversity, conservation effort can be directed, for instance, in the documentation of species that are still unknown to science, or in investigating how species respond to HL&F. The tufted-tail rats genus (Eliurus spp.) is the most speciose genus of endemic rodents in Madagascar, with 13 described species, which occupy two major habitat types: dry or humid forests. The large species diversity and association to specific habitat types make the Eliurus genus a suitable model for investigating species adaptation to new environments, as well as response to HL&F (dry vs humid). In the present study, we investigated Eliurus spp. genomic diversity across northern Madagascar, a region covered by both dry and humid fragmented forests. From the mitochondrial DNA (mtDNA) and nuclear genomic (RAD-seq) data of 124 Eliurus individuals sampled in poorly studied forests of northern Madagascar, we identified an undescribed Eliurus taxon (Eliurus sp. nova). We tested the hypothesis of a new Eliurus species using several approaches: i) DNA barcoding; ii) phylogenetic inferences; iii) species delimitation tests based on the Multi-Species Coalescent (MSC) model, iv) genealogical divergence index (gdi); v) an ad-hoc test of isolation-by-distance within versus between sister-taxa, vi) comparisons of %GC content patterns and vii) morphological analyses. All analyses support the recognition of the undescribed lineage as a putative distinct species. In addition, we show that Eliurus myoxinus, a species known from the dry forests of western Madagascar, is, surprisingly, found mostly in humid forests in northern Madagascar. In conclusion, we discuss the implications of such findings in the context of Eliurus species evolution and diversification, and use the distribution of northern Eliurus species as a proxy for reconstructing past changes in forest cover and vegetation type in northern Madagascar.


Asunto(s)
Biodiversidad , Ecosistema , Ratas , Animales , Filogenia , Madagascar , Bosques , Roedores/genética , ADN Mitocondrial/genética , Genómica
2.
Skin Res Technol ; 30(3): e13632, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38407411

RESUMEN

BACKGROUND: The Grand-AID research project, consisting of GRANDEL-The Beautyness Company, the dermatology department of Augsburg University Hospital and the Chair of IT Infrastructure for Translational Medical Research at Augsburg University, is currently researching the development of a digital skin consultation tool that uses artificial intelligence (AI) to analyze the user's skin and ultimately perform a personalized skin analysis and a customized skin care routine. Training the AI requires annotation of various skin features on facial images. The central question is whether videos are better suited than static images for assessing dynamic parameters such as wrinkles and elasticity. For this purpose, a pilot study was carried out in which the annotations on images and videos were compared. MATERIALS AND METHODS: Standardized image sequences as well as a video with facial expressions were taken from 25 healthy volunteers. Four raters with dermatological expertise annotated eight features (wrinkles, redness, shine, pores, pigmentation spots, dark circles, skin sagging, and blemished skin) with a semi-quantitative and a linear scale in a cross-over design to evaluate differences between the image modalities and between the raters. RESULTS: In the videos, most parameters tended to be assessed with higher scores than in the images, and in some cases significantly. Furthermore, there were significant differences between the raters. CONCLUSION: The present study shows significant differences between the two evaluation methods using image or video analysis. In addition, the evaluation of the skin analysis depends on subjective criteria. Therefore, when training the AI, we recommend regular training of the annotating individuals and cross-validation of the annotation.


Asunto(s)
Inteligencia Artificial , Piel , Humanos , Elasticidad , Cara/diagnóstico por imagen , Proyectos Piloto , Piel/diagnóstico por imagen , Estudios Cruzados
3.
New Microbiol ; 46(2): 95-119, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37247231

RESUMEN

Although progress has led to a drop in infections, meningitis still represents a threat worldwide, affecting some areas more than others. As a medical emergency, it requires prompt recognition and treatment. Moreover, diagnosis relies on invasive methods, while representing a tug-of-war with timely therapeutic interventions, since delays are burdened by mortality and life-long sequalae. While counterbalancing the overuse of antimicrobials, it is imperative to assess correct interventions in order to optimize treatments and reduce negative outcomes. Because the drop in mortality and consequences has been consistent, although not as impactful as with other vaccine-preventable diseases, the WHO has traced a roadmap detailing actions to reduce the meningitis burden by 2030. There are currently no updated guidelines, whereas novel diagnostic methods as well as pharmacological interventions are increasing, along with the shifting epidemiology. In light of the above, this paper wishes to summarize existing data and evidences and suggest potential novel solutions to a complex problem.


Asunto(s)
Meningitis , Micosis , Humanos , Sistema Nervioso Central , Micosis/diagnóstico , Micosis/tratamiento farmacológico
4.
Sensors (Basel) ; 21(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206328

RESUMEN

In this work, a sensitivity analysis for the closed-form approach of irradiance sensing through photovoltaic devices is proposed. A lean expression to calculate irradiance on a photovoltaic device, given its operating point, temperature and equivalent circuit model, is proposed. On this expression, the sensitivity towards errors in the measurement of the photovoltaic device operating point and temperature is analyzed, determining optimal conditions to minimize sensitivity. The approach is studied for two scenarios, a stand-alone sensor and irradiance sensing on an operating power-producing photovoltaic device. A low-cost realization of a virtual sensor employing the closed form for monitoring performance of photovoltaic module is also presented, showing the advantage of this kind of simple solution. The proposed solution can be used to create a wireless sensor network for remote monitoring of a photovoltaic plant, assessing both electrical and environmental conditions of the devices in real time.


Asunto(s)
Energía Solar , Electricidad , Temperatura
5.
Klin Monbl Augenheilkd ; 238(2): 146-152, 2021 Feb.
Artículo en Inglés, Alemán | MEDLINE | ID: mdl-33543764

RESUMEN

Glaucoma patients often bear a long-lasting burden of disease. This can result in anxiety and stress. Causes and effects of anxiety are identified and case studies illustrate how to deal with them. Some knowledge of psychosomatic management is helpful for doctors in dealing with their patients to provide necessary treatment in a less fearful and stressful format.


Asunto(s)
Glaucoma , Médicos , Estudios de Seguimiento , Glaucoma/cirugía , Humanos , Trastornos Psicofisiológicos/diagnóstico
6.
Future Oncol ; 16(12): 763-778, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32250169

RESUMEN

Aim: To differentiate Warthin tumors (WTs) and pleomorphic adenomas (PAs) measuring heterogeneity of intravoxel incoherent motion (IVIM) and dynamic-contrast enhanced-magnetic resonance imaging biomarkers. Methods: Volumes of interest were traced on 18 WT and 18 PA in 25 patients. For each IVIM and dynamic-contrast enhanced biomarker, histogram parameters were calculated and then compared using the Wilcoxon-signed-rank test. Receiver operating characteristic curves and multivariate analysis were employed to identify the parameters and their pairs with the best accuracy. Results: Most of the biomarkers exhibited significant difference (p < 0.05) between PA and WT for histogram parameters. Time to peak median and skewness, and D* median and entropy showed the highest area under the curve. No meaningful improvement of accuracy was obtained using two features. Conclusion: IVIM and dynamic-contrast enhanced histogram descriptors may help in the classification of WT and PA.


Asunto(s)
Neoplasias de la Parótida/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Variación Biológica Poblacional , Estudios de Factibilidad , Femenino , Histocitoquímica , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Clasificación del Tumor , Estadificación de Neoplasias , Curva ROC , Estudios Retrospectivos , Adulto Joven
7.
Am J Primatol ; 81(12): e23070, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31808195

RESUMEN

Tropical forests harbor extremely high levels of biological diversity and are quickly disappearing. Despite the increasingly recognized high rate of habitat loss, it is expected that new species will be discovered as more effort is put to document tropical biodiversity. Exploring under-studied regions is particularly urgent if we consider the rapid changes in habitat due to anthropogenic activities. Madagascar is known for its extraordinary biological diversity and endemicity. It is also threatened by habitat loss and fragmentation. It holds more than 100 endemic primate species (lemurs). Among these, Microcebus (mouse lemurs) is one of the more diverse genera. We sampled mouse lemurs from several sites across northern Madagascar, including forests never sampled before. We obtained morphological data from 99 Microcebus individuals; we extracted DNA from tissue samples of 42 individuals and amplified two mitochondrial loci (cytb and cox2) commonly used for species identification. Our findings update the distribution of three species (Microcebus tavaratra, Microcebus arnholdi, and Microcebus mamiratra), including a major increase in the distribution area of M. arnholdi. We also report the discovery of a new Microcebus lineage genetically related to M. arnholdi. Several complementary approaches suggest that the newly identified Microcebus lineage might correspond to a new putative species, to be confirmed or rejected with additional data. In addition, morphological analyses showed (a) clear phenotypic differences between M. tavaratra and M. arnholdi, but no clear differences between the new Microcebus lineage and the sister species M. arnholdi; and (b) a significant correlation between climatic variables and morphology, suggesting a possible relationship between species identity, morphology, and environment. By integrating morphological, climatic, genetic, and spatial data of two northern Microcebus species, we show that the spatial distribution of forest-dwelling species may be used as a proxy to reconstruct the past spatial changes in forest cover and vegetation type.


Asunto(s)
Distribución Animal , Cheirogaleidae/anatomía & histología , Cheirogaleidae/genética , Animales , Cheirogaleidae/clasificación , ADN Mitocondrial/análisis , Ecosistema , Madagascar
8.
Mar Drugs ; 16(10)2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30297608

RESUMEN

Bacteria of the family Rhodobacteraceae are widespread in marine environments and known to colonize surfaces, such as those of e.g., oysters and shells. The marine bacterium Labrenzia sp. 011 is here investigated and it was found to produce two cyclopropane-containing medium-chain fatty acids (1, 2), which inhibit the growth of a range of bacteria and fungi, most effectively that of a causative agent of Roseovarius oyster disease (ROD), Pseudoroseovarius crassostreae DSM 16950. Additionally, compound 2 acts as a potent partial, ß-arrestin-biased agonist at the medium-chain fatty acid-activated orphan G-protein coupled receptor GPR84, which is highly expressed on immune cells. The genome of Labrenzia sp. 011 was sequenced and bioinformatically compared with those of other Labrenzia spp. This analysis revealed several cyclopropane fatty acid synthases (CFAS) conserved in all Labrenzia strains analyzed and a putative gene cluster encoding for two distinct CFASs is proposed as the biosynthetic origin of 1 and 2.


Asunto(s)
Antibacterianos/farmacología , Organismos Acuáticos/metabolismo , Ciclopropanos/farmacología , Ácidos Grasos/farmacología , Receptores de Superficie Celular/metabolismo , Rhodobacteraceae/metabolismo , Animales , Antibacterianos/metabolismo , Ciclopropanos/metabolismo , Ácidos Grasos/metabolismo , Metiltransferasas/metabolismo , Ostreidae/microbiología , beta-Arrestinas/metabolismo
9.
Planta Med ; 83(12-13): 1044-1052, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28081580

RESUMEN

Natural products from fungi, especially Ascomycota, play a major role in therapy and drug discovery. Fungal strains originating from marine habitats offer a new avenue for finding unusual molecular skeletons. Here, the marine-derived fungus Epicoccum nigrum (strain 749) was found to produce the azaphilonoid compounds acetosellin and 5',6'-dihydroxyacetosellin. The latter is a new natural product. The biosynthesis of these polyketide-type compounds is intriguing, since two polyketide chains are assembled to the final product. Here we performed 13C labeling studies on solid cultures to prove this hypothesis for acetosellin biosynthesis.


Asunto(s)
Ascomicetos/química , Productos Biológicos/química , Policétidos/química , Ascomicetos/metabolismo , Productos Biológicos/metabolismo , Isótopos de Carbono/análisis , Descubrimiento de Drogas , Estructura Molecular , Policétidos/metabolismo
11.
Biomolecules ; 14(4)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38672514

RESUMEN

Circulating cell-free DNA (cfDNA) refers to small fragments of DNA molecules released after programmed cell death and necrosis in several body fluids such as blood, saliva, urine, and cerebrospinal fluid. The discovery of cfDNA has revolutionized the field of non-invasive diagnostics in the oncologic field, in prenatal testing, and in organ transplantation. Despite the potential of cfDNA and the solid results published in the recent literature, several challenges remain, represented by a low abundance, a need for highly sensitive assays, and analytical issues. In this review, the main technical advances in cfDNA analysis are presented and discussed, with a comprehensive examination of the current available methodologies applied in each field. Considering the potential advantages of cfDNA, this biomarker is increasing its consensus among clinicians, as it allows us to monitor patients' conditions in an easy and non-invasive way, offering a more personalized care. Nevertheless, cfDNA analysis is still considered a diagnostic marker to be further validated, and very few centers are implementing its analysis in routine diagnostics. As technical improvements are enhancing the performances of cfDNA analysis, its application will transversally improve patients' quality of life.


Asunto(s)
Ácidos Nucleicos Libres de Células , Medicina de Precisión , Humanos , Medicina de Precisión/métodos , Ácidos Nucleicos Libres de Células/sangre , Ácidos Nucleicos Libres de Células/genética , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/sangre , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo
12.
Clin Drug Investig ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39172297

RESUMEN

BACKGROUND AND OBJECTIVE: Untreated spinal muscular atrophy (SMA) is the leading genetic cause of death in children younger than 2 years of age. Early detection through newborn screening allows for presymptomatic diagnosis and treatment of SMA. With effective treatments available and reimbursed by the National Health Service, many regions in Italy are implementing newborn screening for SMA. We evaluated the cost effectiveness of universal newborn screening for SMA in Italy. METHODS: A decision-analytic model assessed the cost effectiveness of newborn screening from the National Health Service perspective in 400,000 newborns. Newborn screening enabling early identification and presymptomatic treatment of SMA was compared with no newborn screening, symptomatic diagnosis, and treatment. Transition probabilities between health states were estimated from clinical trial data. Higher-functioning health states were associated with increased survival, higher utility values, and lower costs. Long-term survival and utilities were extrapolated from scientific literature. Health care costs were collected from official Italian sources. A lifetime time horizon was applied, and costs and outcomes were discounted at an annual rate of 3%. Deterministic and probabilistic sensitivity analyses were conducted. RESULTS: Newborn screening followed by presymptomatic treatment yielded 324 incremental life-years, 390 incremental quality-adjusted life-years, and reduced costs by €1,513,375 over a lifetime time horizon compared with no newborn screening. Thus, newborn screening was less costly and more effective than no newborn screening. Newborn screening has a 100% probability of being cost effective, assuming a willingness-to-pay threshold of > €40,000. CONCLUSIONS: Newborn screening followed by presymptomatic SMA treatment is cost effective from the Italian National Health Service perspective.

13.
Infect Dis Rep ; 16(1): 93-104, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38391585

RESUMEN

The subcutaneous (s.c.) route is a commonly used method for delivering various drugs, although its application in the administration of antibiotics is relatively uncommon. In this case, we report a successful treatment of nosocomial pneumonia using piperacillin/tazobactam via continuous subcutaneous administration. Furthermore, this article provides an overview of the current literature regarding the s.c. administration of beta-lactam antibiotics. Based on our analysis, we identified only 15 studies that described the s.c. use of beta-lactam antibiotics in human subjects. Among these studies, cephalosporins were the most extensively investigated antibiotic class, with 10 available studies. According to the study findings, all three antibiotic classes (cephalosporins, penicillins, and carbapenems) demonstrated a similar pharmacokinetic profile when administered via the subcutaneous route. The subcutaneous route appears to be associated with a lower peak serum concentration (Cmax) but a comparable minimum blood concentration (Cmin) and an extended half-life (t1/2) when compared to conventional routes of antibiotic administration. Further research is necessary to determine whether subcutaneously administered beta-lactam antibiotics in human subjects achieve pharmacodynamic targets and demonstrate clinical efficacy.

14.
Diagn Microbiol Infect Dis ; 109(1): 116205, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38422663

RESUMEN

External ventricular drain-related cerebrospinal fluid infection represents a fearsome complication of neurosurgical interventions. Although vancomycin represents the standard of care for methicillin-resistant CoNS healthcare-associated ventriculitis, resistance phenomena have been described. We reported a case of a persistent external ventricular fluid drain infection after device removal by pandrug-resistant Staphylococcus epidermidis successfully treated with intravenous ceftaroline in combination with fosfomycin and vancomycin. No evidence regarding pandrug-resistant S. epidermidis therapy currently exists to our knowledge. In this case, the S. epidermidis phenotype emerged during the therapy course, possibly due to initial device retention, biofilm formation and the host immune impaired response. Despite being poorly studied in vivo, ceftaroline may be considered an option when other alternatives are unavailable, thanks to its described activity against CoNS in vitro. This case extends the experience with ceftaroline for central nervous system infections suggesting it could also be used in high antimicrobial resistance settings for immunocompromised people.


Asunto(s)
Fosfomicina , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Ceftarolina , Vancomicina/uso terapéutico , Antibacterianos/uso terapéutico , Staphylococcus epidermidis/genética , Fosfomicina/uso terapéutico , Cefalosporinas/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Drenaje , Pruebas de Sensibilidad Microbiana
15.
Am J Case Rep ; 25: e941165, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943241

RESUMEN

BACKGROUND SARS-CoV-2 infection can persist in immunocompromised patients with hematological malignancies, despite antiviral treatment. This report is of a 67-year-old man with chronic lymphocytic leukemia (CLL), secondary hypogammaglobulinemia, and thrombocytopenia on maintenance therapy with ibrutinib, with persistent SARS-CoV-2 infection unresponsive to antiviral treatment, including remdesivir, nirmatrelvir/ritonavir (Paxlovid), and tixagevimab/cilgavimab (Evusheld). CASE REPORT The patient was admitted to our hospital 3 times. During his first hospitalization, he was treated with 5-day course of remdesivir and intravenous steroids; however, antigen and molecular nasopharyngeal swabs were persistently positive, and he was discharged home. Due to respiratory worsening, he was rehospitalized, and despite being treated initially with tixagevimab/cilgavimab, and subsequently with a remdesivir course of 5 days, SARS-CoV-2 tests remained persistently positive. During his third hospital stay, our patient was subjected to combined therapy with remdesivir and nirmatrelvir/ritonavir for 5 days, obtaining a significant reduction of viral load at both antigen and molecular testing. As an ultimate attempt to achieve a negative status before discharge, a 10-day course of combined remdesivir and nirmatrelvir/ritonavir was administered, with a temporary reduction of viral load, followed by a sudden increase immediately after the discontinuation of Paxlovid. Due to worsening hematological disease and bacterial over-infections, the patient gradually worsened until death. CONCLUSIONS This is an emblematic case of correlation between persistent SARS-CoV-2 infection and immunosuppression status in hematological hosts. In these patients, the viral load remains high, favoring the evolution of the virus, and the immunodeficiency makes it difficult to identify the appropriate therapeutic approach.


Asunto(s)
Adenina , COVID-19 , Leucemia Linfocítica Crónica de Células B , Piperidinas , Humanos , Masculino , Anciano , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/complicaciones , Adenina/análogos & derivados , Adenina/uso terapéutico , COVID-19/diagnóstico , Piperidinas/uso terapéutico , Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , SARS-CoV-2 , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/uso terapéutico , Alanina/análogos & derivados , Alanina/uso terapéutico , Huésped Inmunocomprometido , Quimioterapia de Mantención
16.
J Acoust Soc Am ; 134(1): 782-90, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23862884

RESUMEN

An experimental study was carried out in 20 squares in the center of Rome, covering a wide range of different uses, sonic environments, geometry, and architectural styles. Soundwalks along the perimeter of each square were performed during daylight and weekdays taking binaural and video recordings, as well as spot measurements of illuminance. The cluster analysis performed on the physical parameters, not only acoustic, provided two clusters that are in satisfactory agreement with the "a priori" classification. Applying the principal component analysis (PCA) to five physical parameters, two main components were obtained which might be associated to two environmental features, namely, "chaotic/calm" and "open/enclosed." On the basis of these two features, six squares were selected for the laboratory audio-video tests where 32 subjects took part filling in a questionnaire. The PCA performed on the subjective ratings on the sonic environment showed two main components which might be associated to two emotional meanings, namely, "calmness" and "vibrancy." The linear regression modeling between five objective parameters and the mean value of subjective ratings on chaotic/calm and enclosed/open attributes showed a good correlation. Notwithstanding these interesting results being limited to the specific data set, it is worth pointing out that the complexity of the soundscape quality assessment can be more comprehensively examined merging the field measurements of physical parameters with the subjective ratings provided by field and/or laboratory tests.

17.
Life (Basel) ; 13(5)2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37240771

RESUMEN

Multidrug-resistant Staphylococcus epidermidis (MDRSE) is responsible for difficult-to-treat infections in humans and hospital-acquired-infections. This review discusses the epidemiology, microbiology, diagnosis, and treatment of MDRSE infection and identifies knowledge gaps. By using the search term "pan resistant Staphylococcus epidermidis" OR "multi-drug resistant Staphylococcus epidermidis" OR "multidrug-resistant lineages of Staphylococcus epidermidis", a total of 64 records have been identified from various previously published studies. The proportion of methicillin resistance in S. epidermidis has been reported to be as high as 92%. Several studies across the world have aimed to detect the main phylogenetic lineages and antibiotically resistant genes through culture, mass spectrometry, and genomic analysis. Molecular biology tools are now available for the identification of S. epidermidis and its drug resistance mechanisms, especially in blood cultures. However, understanding the distinction between a simple colonization and a bloodstream infection (BSI) caused by S. epidermidis is still a challenge for clinicians. Some important parameters to keep in mind are the number of positive samples, the symptoms and signs of the patient, the comorbidities of the patient, the presence of central venous catheter (CVC) or other medical device, and the resistance phenotype of the organism. The agent of choice for empiric parenteral therapy is vancomycin. Other treatment options, depending on different clinical settings, may include teicoplanin, daptomycin, oxazolidinones, long-acting lipoglycopeptides, and ceftaroline. For patients with S. epidermidis infections associated with the presence of an indwelling device, assessment regarding whether the device warrants removal is an important component of management. This study provides an overview of the MDRSE infection. Further studies are needed to explore and establish the most correct form of management of this infection.

18.
ACS Biomater Sci Eng ; 9(12): 6926-6934, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37824106

RESUMEN

This work reports the design and validation of an innovative automatic photo-cross-linking device for robotic-based in situ bioprinting. Photo-cross-linking is the most promising polymerization technique when considering biomaterial deposition directly inside a physiological environment, typical of the in situ bioprinting approach. The photo-cross-linking device was designed for the IMAGObot platform, a 5-degree-of-freedom robot re-engineered for in situ bioprinting applications. The system consists of a syringe pump extrusion module equipped with eight light-emitting diodes (LEDs) with a 405 nm wavelength. The hardware and software of the robot were purposely designed to manage the LEDs switching on and off during printing. To minimize the light exposure of the needle, thus avoiding its clogging, only the LEDs opposite the printing direction are switched on to irradiate the newly deposited filament. Moreover, the LED system can be adjusted in height to modulate substrate exposure. Different scaffolds were bioprinted using a GelMA-based hydrogel, varying the printing speed and light distance from the bed, and were characterized in terms of swelling and mechanical properties, proving the robustness of the photo-cross-linking system in various configurations. The system was finally validated onto anthropomorphic phantoms (i.e., a human humerus head and a human hand with defects) featuring complex nonplanar surfaces. The designed system was successfully used to fill these anatomical defects, thus resulting in a promising solution for in situ bioprinting applications.


Asunto(s)
Bioimpresión , Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Bioimpresión/métodos , Impresión Tridimensional , Gelatina/química
19.
Bioengineering (Basel) ; 10(5)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37237631

RESUMEN

This study aims to critically analyse the workflow of the in situ bioprinting procedure, presenting a simulated neurosurgical case study, based on a real traumatic event, for collecting quantitative data in support of this innovative approach. After a traumatic event involving the head, bone fragments may have to be removed and a replacement implant placed through a highly demanding surgical procedure in terms of surgeon dexterity. A promising alternative to the current surgical technique is the use of a robotic arm to deposit the biomaterials directly onto the damaged site of the patient following a planned curved surface, which can be designed pre-operatively. Here we achieved an accurate planning-patient registration through pre-operative fiducial markers positioned around the surgical area, reconstructed starting from computed tomography images. Exploiting the availability of multiple degrees of freedom for the regeneration of complex and also overhanging parts typical of anatomical defects, in this work the robotic platform IMAGObot was used to regenerate a cranial defect on a patient-specific phantom. The in situ bioprinting process was then successfully performed showing the great potential of this innovative technology in the field of cranial surgery. In particular, the accuracy of the deposition process was quantified, as well as the duration of the whole procedure was compared to a standard surgical practice. Further investigations include a biological characterisation over time of the printed construct as well as an in vitro and in vivo analysis of the proposed approach, to better analyse the biomaterial performances in terms of osteo-integration with the native tissue.

20.
Antibiotics (Basel) ; 12(6)2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37370320

RESUMEN

(1) Background: Infections are among the most frequent and life-threatening complications of cardiovascular implantable electronic device (CIED) implantation. The aim of this study is to compare the outcome and safety of a single-procedure device extraction and contralateral implantation versus the standard-of-care (SoC) two-stage replacement for infected CIEDs. (2) Methods: We retrospectively included 66 patients with CIED infections who were treated at two Italian hospitals. Of the 66 patients enrolled in the study, 27 underwent a single procedure, whereas 39 received SoC treatment. All patients were followed up for 12 months after the procedure. (3) Results: Considering those lost to follow-up, there were no differences in the mortality rates between the two cohorts, with survival rates of 81.5% in the single-procedure group and 84.6% in the SoC group (p = 0.075). (4) Conclusions: Single-procedure reimplantation associated with an active antibiofilm therapy may be a feasible and effective therapeutic option in CIED-dependent and frail patients. Further studies are warranted to define the best treatment regimen and strategies to select patients suitable for the single-procedure reimplantation.

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