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1.
Clin Transl Radiat Oncol ; 47: 100789, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38741926

RESUMO

Background: The impact of body composition and sarcopenia in locally advanced rectal cancer (LARC) is still unclear, even several studies have been published on this issue. Our study aims to analyze the impact of sarcopenia on neoadjuvant chemoradiotherapy (nCRT) tolerance and survival outcomes. Methods: This is a retrospective, monocentric study where LARC patients treated between 2010 and 2020 were enrolled. A single slice, from the pre-therapy simulation computed tomography (CT) scan, was used to perform the body composition analysis with dedicated software. The primary endpoint was the impact of body composition on radiotherapy (RT) interruption secondarily on overall survival (OS), disease-free survival (DFS), and local control (LC). Results: The study included 628 LARC patients (40.9 % female, mean age 63.4 years): 24 % had low skeletal muscle index (SMI), 30 % had low muscle density (MD) and 17 (10.3 % of obese) were sarcopenic obese. Higher BMI (OR 2.38, 95 % CI 1.36-4.01) and lower SMI (0.73, 95 % CI 0.55-0.94) resulted as independent predictors of RT interruption. Sarcopenic obesity (HR 2.83, 95 % CI 1.24-6.45) was related to worse OS, while MD (0.96, 95 % CI 0.93-0.98), and higher SMI (0.97, 95 % CI 0.95-0.99) were related to better OS; a lower MD remained also associated even in adjusted multivariable analysis (0.96, 95 % CI0.93-0.98). Moreover, higher visceral adipose tissue (VAT) resulted associated with worse DFS (1.02, 95 % CI 1.01-1.03), while higher SMI was related to better Local Control (0.96, 95 % CI 0.93-0.99). Conclusions: Body composition analysis, particularly of muscle and fat masses, may be a useful tool for better management of LARC patients undergoing RT. Increased collaboration between radiation oncologists and clinical nutritionists is advisable, to enable early nutritional support of LARC.

2.
J Am Acad Orthop Surg ; 32(3): e134-e145, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37824083

RESUMO

BACKGROUND: Intramedullary nail fixation is commonly used for prophylactic stabilization of impending and fixation of complete pathological fractures of the long bones. However, metallic artifacts complicate imaging evaluation for bone healing or tumor progression and postoperative radiation planning. Carbon-fiber implants have gained popularity as an alternative, given their radiolucency and superior axial bending. This study evaluates incidences of mechanical and nonmechanical complications. METHODS: Adult patients (age 18 years and older) treated with carbon-fiber nails for impending/complete pathological long bone fractures secondary to metastases from 2013 to 2020 were analyzed for incidences and risk factors of mechanical and nonmechanical complications. Mechanical complications included aseptic screw loosening and structural failures of host bone and carbon-fiber implants. Deep infection and tumor progression were considered nonmechanical. Other complications/adverse events were also reported. RESULTS: A total of 239 patients were included; 47% were male, and 53% were female, with a median age of 68 (IQR, 59 to 75) years. Most common secondary metastases were related to breast cancer (19%), lung cancer (19%), multiple myeloma (18%), and sarcoma (13%). In total, 17 of 30 patients with metastatic sarcoma received palliative intramedullary nail fixation for impending/complete pathological fractures, and 13 of 30 received prophylactic nail stabilization of bone radiated preoperatively to manage juxta-osseous soft-tissue sarcomas, where partial resection of the periosteum or bone was necessary for negative margin resection. 33 (14%) patients had complications. Mechanical failures included 4 (1.7%) structural host bone failures, 7 (2.9%) implant structural failures, and 1 (0.4%) aseptic loosening of distal locking screws. Nonmechanical failures included 8 (3.3%) peri-implant infections and 15 (6.3%) tumor progressions with implant contamination. The 90-day and 1-year mortalities were 28% (61/239) and 53% (53/102), respectively. The literature reported comparable failure and mortality rates with conventional titanium treatment. CONCLUSIONS: Carbon-fiber implants might be an alternative for treating impending and sustained pathological fractures secondary to metastatic bone disease. The seemingly comparable complication profile warrants further cohort studies comparing carbon-fiber and titanium nail complications.


Assuntos
Fixação Intramedular de Fraturas , Fraturas Espontâneas , Sarcoma , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pinos Ortopédicos , Fibra de Carbono , Fixação Intramedular de Fraturas/métodos , Fraturas Espontâneas/etiologia , Titânio , Resultado do Tratamento
3.
Curr Oncol ; 30(10): 9335-9345, 2023 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-37887575

RESUMO

Giant cell tumors of bone are a rare entity, usually occurring in young patients and characteristically arising in the long bones. The spinal location is rare and usually presents with pain and/or neurological symptoms. The treatment of choice is surgery. Treatment with Denosumab, a bisphosphonate inhibitor of RANK-L, which is highly expressed in these tumors, has shown extensive activity in unresectable patients or those undergoing incomplete surgery. Preoperative treatment with this drug is gaining increasing interest, as its high potency in tumor reduction in this subtype of neoplasm has allowed resectability in selected patients. We present the case of a young patient with a large spinal tumor who, after neoadjuvant Denosumab, underwent complete en bloc surgery with clean margins and a great pathological response.


Assuntos
Conservadores da Densidade Óssea , Tumor de Células Gigantes do Osso , Neoplasias da Coluna Vertebral , Humanos , Denosumab/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Terapia Neoadjuvante , Tumor de Células Gigantes do Osso/tratamento farmacológico , Tumor de Células Gigantes do Osso/cirurgia , Neoplasias da Coluna Vertebral/tratamento farmacológico , Neoplasias da Coluna Vertebral/patologia , Células Gigantes/patologia
4.
Healthcare (Basel) ; 11(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37830695

RESUMO

BACKGROUND: Aneurysmal bone cysts (ABCs) are benign but locally aggressive cystic lesions of the bone. Pelvic ABCs are extremely rare and hard to treat due to their high risk of local recurrence and the tough access to pelvic bones. METHODS: In this retrospective study, we evaluated pediatric cases with pelvic ABC treated with curettage, cryotherapy and bone grafting treated in our institution between 2016 and 2022. Complications were recorded, as well as local recurrences. Patients' post-operative functionality was assessed with the MSTS score. RESULTS: Fourteen consecutive cases were included in our study. Their mean age at surgery was 13.5 years. The mean lesion size was 55 mm. The mean follow-up was 38 months. Two cases (11.8%) had local recurrences, which were successfully treated with further curettage. At their latest FU, 13 cases were continuously disease free (CDF), and one had no evidence of disease (NED). Only one case had a post-operative compilation (wound dehiscence). Patients' mean post-operative MSTS score was 29.6. CONCLUSIONS: Pelvic ABCs are a challenge, even for the most experienced orthopedic surgeon. Our study suggests that the association of an accurate curettage, intraoperative cryotherapy and bone grafting can be a reliable and effective therapeutic option for large-sized ABCs of the pelvis.

5.
Healthcare (Basel) ; 11(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37444784

RESUMO

To evaluate the adoption of an integrated eHealth platform for televisit/monitoring/consultation during the COVID-19 pandemic. METHODS: During the lockdown imposed by the Italian government during the COVID19 pandemic spread, a dedicated multi-professional working group was set up in the Radiation Oncology Department with the primary aim of reducing patients' exposure to COVID-19 by adopting de-centralized/remote consultation methodologies. Each patient's clinical history was screened before the visit to assess if a traditional clinical visit would be recommended or if a remote evaluation was to be preferred. Real world data (RWD) in the form of patient-reported outcomes (PROMs) and patient reported experiences (PREMs) were collected from patients who underwent televisit/teleconsultation through the eHealth platform. RESULTS: During the lockdown period (from 8 March to 4 May 2020) a total of 1956 visits were managed. A total of 983 (50.26%) of these visits were performed via email (to apply for and to upload of documents) and phone call management; 31 visits (1.58%) were performed using the eHealth system. Substantially, all patients found the eHealth platform useful and user-friendly, consistently indicating that this type of service would also be useful after the pandemic. CONCLUSIONS: The rapid implementation of an eHealth system was feasible and well-accepted by the patients during the pandemic. However, we believe that further evidence is to be generated to further support large-scale adoption.

6.
Adv Orthop ; 2023: 1868943, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36938102

RESUMO

Background: Knee osteoarthritis is a common disease with increasing incidence and prevalence in western countries. It can cause severe pain and functional limitations, thereby representing a threat for patients' quality of life and a burden for national health systems. Intra-articular injections with hyaluronic acid (HA) and platelet-rich plasma (PRP) have been used for decades in order to reduce the symptoms caused by osteoarthritis. In recent years, a combination of HA and PRP has been introduced in clinical practice with the aim to minimize the clinical presentation of osteoarthritis and potentially delay articular degeneration. Materials and Methods: Sixty cases with grade II-III knee osteoarthritis according to the Kellgren-Lawrence classification were included in a prospective study, focused on the evaluation of clinical and functional outcomes after intra-articular knee injections. Cases were randomly divided into three groups. Twenty cases (Group A) were injected with HA, 20 (Group B) had PRP, and the remaining 20 (Group C) received a combination of HA and PRP. Basal WOMAC score and VAS score were recorded before the treatment and repeated within 3 and 6 months after the treatment. Results: At 6-month follow-up, Group C (PRP + HA) was the one with the lowest WOMAC and VAS mean values. It was also the only group that reported a reduction in the two values both in the first three months and in the following three months. No major complication was recorded. Conclusion: The combination of platelet-rich plasma and hyaluronic acid can be effective in the treatment of grade II-III knee osteoarthritis in a short-to-mid-term scenario. It represents an innovative and valuable alternative to the administration of its two components alone.

7.
Sci Adv ; 9(10): eadg4392, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36897940

RESUMO

Among hydrocolloids, gellan is one of the most studied polysaccharides due to its ability to form mechanically stable gels. Despite its long-standing use, the gellan aggregation mechanism is still not understood because of the lack of atomistic information. Here, we fill this gap by developing a new gellan force field. Our simulations offer the first microscopic overview of gellan aggregation, detecting the coil to single-helix transition at dilute conditions and the formation of higher-order aggregates at high concentration through a two-step process: first, the formation of double helices and then their assembly into superstructures. For both steps, we also assess the role of monovalent and divalent cations, complementing simulations with rheology and atomic force microscopy experiments and highlighting the leading role of divalent cations. These results pave the way for future use of gellan-based systems in a variety of applications, from food science to art restoration.

8.
Acta Biomed ; 94(1): e2023013, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36786271

RESUMO

BACKGROUND AND AIM: Femoral neck fractures are among the most frequent in mankind. Screw fixation is considered a suitable approach specially for undisplaced or slightly displaced fractures that occur to young patients. We conducted our study in order to evaluate both functional outcomes and complication rates of patients who received this treatment in our institution. A particular focus was given to the aseptic necrosis of the head, trying to identify if anamnestic, clinical or radiological data could play a significant role as prognostic factors. METHODS: For each case who was treated with screw fixation due to a femoral neck fracture, we recorded data regarding, among the others, BMI and whether they used tobacco products or corticosteroids on a regular basis. Necrosis of the femoral head and mechanical complications were recorded. Functional outcome was evaluated using the Harris Hip Score.      Results: 74 cases were included in our study. The mean Harris Hip score was 89.5. Aseptic necrosis of the femoral head occurred in 9 cases (12.2%). Regular use of tobacco was associated with a higher risk to develop necrosis (p=0.007). The Body Mass Index was significantly higher in cases who had necrosis compared to the rest of our population (p=0.043) and was inversely proportional to the post-operative Harris hip score (p=0.001). CONCLUSIONS: While considering screw fixation to treat cases with femoral neck fractures, patient's weight and use of tobacco should be considered as prognostic factors.  (www.actabiomedica.it).


Assuntos
Fraturas do Colo Femoral , Necrose da Cabeça do Fêmur , Cirurgiões , Humanos , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fraturas do Colo Femoral/cirurgia , Parafusos Ósseos/efeitos adversos , Resultado do Tratamento , Estudos Retrospectivos
9.
Acta Med Litu ; 30(2): 163-170, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38516519

RESUMO

Background: Giant cell tumor of the tendon sheath (GCTTS), also termed Tenosynovial giant cell tumor (TGCT), is a locally aggressive tumor which originates from tendon sheaths or bursas. Around 3-5% of these tumors arise from foot and ankle. Localized lesions in this area are often manifested as firm masses or nodules with slow but continuous progression through months and years. Pain associated with weight-bearing, as well as limitations in joint motions, may be reported, depending on tumor's location. Surgery is the treatment of choice for the definitive removal of GCTTSs with the aim to eradicate the neoplasm and restore the lower limb's functionality. Methods: Thirteen cases suffering from GCTTS of the foot and ankle underwent surgical resection at our institution between 2017 and 2022. For each case we recorded pre-operative and post-operative symptoms, as well as their pre-operative and post-operative functional status according to both MSTS and AOFAS scores. Eventual complications and local recurrences were reported. Results: Each patient experienced an at least mild pain before surgical treatment. The mean pre-operative MSTS and AOFAS scores were 22.8 and 70.7, respectively. The mean tumor size was 17.7 mm. Each patient received a resection with wide margins. Two cases (15.4%) had local recurrences. None had major complications at their latest follow-up. After the surgery, the mean post-operative MSTS and AOFAS scores increased to 28.3 and 92.2, respectively. Conclusion: Resection with wide margins for foot and ankle GCTTS is effective in restoring the patients' lower limb functionality and is associated with reasonable local recurrence rates.

10.
J Musculoskelet Neuronal Interact ; 22(1): 87-92, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35234163

RESUMO

OBJECTIVES: Peroneal nerves Schwannomas are rare benign tumors. Literature is still poor of studies about clinical and functional outcomes after surgical treatment. We evaluated the pre-operative presentation of the disease and assessed clinical and functional outcomes after surgery. METHODS: We collected all the cases of peroneal nerves' neurinoma treated surgically between June 2016 and June 2020. We analyzed each patients' personal data and carried out accurate clinical examinations before and after surgery. MRI was performed both pre-operatively and post-operatively. RESULTS: We reported 9 cases of peroneal nerves schwannomas: five arising from the common peroneal nerve and four arising from the deep or superficial branches alone. Their mean size was 22.6 mm. Each patient showed sensation deficits before surgery; pre-operative MRC score was 4.2. Pre-Operative MSTS and LEFS scores were 23.6 and 64.4. Surgery was successful in each case. No local recurrence nor major complication occurred. Tumor size was significantly associated with both diagnostic delay and development of pre-operative deficits. Surgery was proven to be globally successful: post-operative evaluations highlighted a marked reduction of neurological signs and overall functional limitations. CONCLUSIONS: Surgical treatment at early stages of the disease represents a reliable and relatively safe therapeutic option.


Assuntos
Neurilemoma , Nervo Fibular , Diagnóstico Tardio , Humanos , Neurilemoma/diagnóstico por imagem , Neurilemoma/patologia , Neurilemoma/cirurgia , Nervo Fibular/patologia , Nervo Fibular/cirurgia
11.
Acta Biomed ; 93(1): e2022085, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35315411

RESUMO

BACKGROUND AND AIM OF THE WORK: Schwannomas of the lower limb are uncommon benign tumors and those arising from Tibial Nerve are particularly rare. We report our experience on the topic, with particular attention to clinical presentation and lower limbs overall functionality before and after treatment. Our aim is to assess clinical impairment caused by the tumor and evaluate the effectiveness of surgical treatment. MATERIALS AND METHODS: Time between symptoms outbreak and diagnosis, as well as pre- operative tumor size were evaluated for each case. Pre-operative and post-operative overall lower limb functionality were assessed using both MSTS and LEFS scores. Sensitive symptoms and muscular strength were also evaluated before and after surgery. RESULTS: 7 patients were included in our study. The mean follow-up was 22.9 months. Average diagnostic delay was 8 months and tumor size was 29.3mm. Before surgery each patient had positive Hoffmann-Tinel sign and an at least mild paresthesia, 57% of our cases had slight reduction of muscular strength. Pre-operative MSTS score was 24.4 and LEFS score was 64.7. Tumor size and diagnostic delay were associated with pre-operative functionality. No major local complication was recorded during or after surgery. Each patient with pre-operative sensitive or motorial deficit benefited the effects of surgical treatment. CONCLUSIONS: Our cases suggest early diagnosis could reduce the impact of the disease on patients' activities of daily living and quality of life. Surgery, for its part, represents a safe and reliable approach to Tibial Nerve schwannomas with good chances of clinical and functional remission.


Assuntos
Neurilemoma , Neoplasias Cutâneas , Atividades Cotidianas , Diagnóstico Tardio , Humanos , Neurilemoma/diagnóstico , Neurilemoma/cirurgia , Qualidade de Vida , Nervo Tibial/cirurgia
12.
Adv Orthop ; 2021: 5559377, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33828866

RESUMO

Proximal humerus is one of the anatomical sites that are most frequently involved by bone and soft tissue malignant tumors. Alone or in association with adjuvant treatments, surgery represents the main therapeutic option to treat and eradicate these diseases. Once the first-line option, in the last decades, amputation lost its role as treatment of choice for the large majority of cases in favor of the modern limb sparing surgery that promises to preserve anatomy and-as much as possible-upper limb functionality. Currently, the main approaches used to replace proximal humerus after a wide resection in oncologic surgery can be summarized in biological reconstructions (allografts and autografts), prosthetic reconstructions (anatomic endoprostheses, total reverse shoulder prostheses), and graft-prosthetic composite reconstructions. The purpose of this overview is to present nowadays surgical options for proximal humerus reconstruction in oncological patients, with their respective advantages and disadvantages.

13.
Polymers (Basel) ; 13(9)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919087

RESUMO

Microgels composed of stimuli responsive polymers have attracted worthwhile interest as model colloids for theorethical and experimental studies and for nanotechnological applications. A deep knowledge of their behaviour is fundamental for the design of new materials. Here we report the current understanding of a dual responsive microgel composed of poly(N-isopropylacrylamide) (PNIPAM), a temperature sensitive polymer, and poly(acrylic acid) (PAAc), a pH sensitive polymer, at different temperatures, PAAc contents, concentrations, solvents and pH. The combination of multiple techniques as Dynamic Light Scattering (DLS), Raman spectroscopy, Small Angle Neutron Scattering (SANS), rheology and electrophoretic measurements allow to investigate the hydrodynamic radius behaviour across the typical Volume Phase Transition (VPT), the involved molecular mechanism and the internal particle structure together with the viscoelastic properties and the role of ionic charge in the aggregation phenomena.

14.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919803

RESUMO

The phase behaviour of soft colloids has attracted great attention due to the large variety of new phenomenologies emerging from their ability to pack at very high volume fractions. Here we report rheological measurements on interpenetrated polymer network microgels composed of poly(N-isopropylacrylamide) (PNIPAM) and polyacrylic acid (PAAc) at fixed PAAc content as a function of weight concentration. We found three different rheological regimes characteristic of three different states: a Newtonian shear-thinning fluid, an attractive glass characterized by a yield stress, and a jamming state. We discuss the possible molecular mechanisms driving the formation of these states.


Assuntos
Resinas Acrílicas/química , Vidro/química , Reologia , Hidrodinâmica , Resistência ao Cisalhamento , Estresse Mecânico
15.
Med Clin (Engl Ed) ; 156(5): 221-228, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33585689

RESUMO

BACKGROUND: Several studies have reported the beneficial effect of glucocorticoids in the treatment of cytokine storm that occurs in patients with severe COVID-19. Various glucocorticoids regimens have been proposed. METHODS: Retrospective observational study that includes patients with severe SARS-CoV-2 pneumonia and compares admission to an Intensive Care Unit (ICU) or death during hospitalization in three groups of patients: no glucocorticoids treatment, use of glucocorticoids doses equivalent to less than 250 mg of prednisone daily and use of equivalent doses greater than or equal to 250 mg of prednisone daily. Multivariate analysis was performed using logistic regression, using the propensity index as a covariant. RESULTS: Of the 259 patients enrolled in the study, 67 (25.9%) had an unfavorable evolution, dying or requiring ICU admission. Comparative analyzes between different glucocorticoids treatments and the association with ICU admission or death were: glucocorticoids treatment (any dose) versus no glucocorticoids treatment (OR: 0.71 [0.30-1.66]), treatment with glucocorticoids (≥250 mg prednisone daily) versus no glucocorticoids treatment (OR: 0.35 [0.11-1.08]) and glucocorticoids treatment (≥250 mg prednisone daily) versus patients with glucocorticoids doses <250 mg prednisone daily or without glucocorticoids treatment (OR: 0.30 [0.10-0.88]). CONCLUSION: The results of this study show that patients with severe SARS-CoV-2 pneumonia treated with glucocorticoids pulses with equivalent doses of prednisone greater than or equal to 250 mg have a more favorable evolution (less mortality and less admission to ICU).


INTRODUCCIÓN: Se han comunicado varios trabajos donde se ha demostrado un efecto beneficioso de los glucocorticoides como tratamiento de la tormenta de citocinas que se asocia a los cuadros graves por SARS-CoV-2, plateándose diferentes pautas de glucocorticoides. MÉTODOS: Estudio observacional retrospectivo que incluye pacientes con neumonía grave por SARS-CoV-2 y compara el ingreso en una unidad de cuidados intensivos (UCI) o fallecimiento durante la hospitalización en 3 grupos de pacientes: sin tratamiento con glucocorticoides, uso de dosis diarias de glucocorticoides equivalentes menores a 250 mg de prednisona y dosis diarias equivalentes mayores o iguales a 250 mg de prednisona. Se realizó un análisis multivariante mediante regresión logística, utilizando el índice de propensión como covariante. RESULTADOS: De los 259 pacientes incorporados al estudio 67 (25,9%) tuvieron una evolución desfavorable, falleciendo o precisando ingreso en UCI. Los análisis comparativos entre diferentes tratamientos con glucocorticoides, y la asociación con ingreso en UCI o fallecimiento fueron: tratamiento con glucocorticoides (cualquier dosis) versus sin tratamiento con glucocorticoides (OR: 0,71 [0,30­1,66]), tratamiento con glucocorticoides (≥250 mg de prednisona al día) versus sin tratamiento con glucocorticoides (OR: 0,35 [0,11­1,08]) y tratamiento con glucocorticoides (≥250 mg de prednisona al día) versus pacientes con dosis de glucocorticoides < 250 mg de prednisona o sin tratamiento con glucocorticoides (OR: 0,30 [0,10­0,88]). CONCLUSIÓN: Los resultados de este estudio muestran que los paciente con neumonía grave por SARS-CoV-2 tratados con pulsos con glucocorticoides con dosis equivalentes de prednisona mayor o igual de 250 mg tienen una evolución más favorable (menos mortalidad e ingreso en UCI).

16.
RSC Adv ; 11(55): 34449-34455, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-35494751

RESUMO

Alginate is a natural polysaccharide that has been recently gaining increasing attention as a biomaterial in the field of tissue engineering due to its favourable biocompatibility and gelation properties. Alginate hydrogels are commonly made by ionic crosslinking in the presence of divalent cations. Only a few studies have attempted to prepare alginate hydrogels without the presence of metal cations. Here the formation of metal free alginate hydrogels in the presence of the amino-acid glutamine is investigated. The transition from sol to gel is monitored by rheological measurements in the viscoelastic regime that reveal how the charged or neutral form of glutamine induces deep differences in the gelling ability. In particular, we show that the storage, G', and loss, G'', moduli differ significantly by shifting the glutamine zwitterionic equilibrium. Protonated amino acid could induce a shielding effect of the electrostatic repulsion of the alginate chains. Stable gels are obtained in the presence of a larger amount of free organic acid that gives rise to chain crosslink junctions and chain-chain stabilization. This opens up the possibility of preparing metal-free alginate hydrogels based on amino acid equilibria being pH sensitive.

17.
Med Clin (Barc) ; 156(5): 221-228, 2021 03 12.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33380371

RESUMO

INTRODUCTION: Several studies have reported the beneficial effect of glucocorticoids in the treatment of cytokine storm that occurs in patients with severe COVID-19. Various glucocorticoids regimens have been proposed. METHODS: Retrospective observational study that includes patients with severe SARS-CoV-2 pneumonia and compares admission to an Intensive Care Unit (ICU) or death during hospitalization in three groups of patients: no glucocorticoids treatment, use of glucocorticoids doses equivalent to less than 250mg of prednisone daily and use of equivalent doses greater than or equal to 250mg of prednisone daily. Multivariate analysis was performed using logistic regression, using the propensity index as a covariant. RESULTS: Of the 259 patients enrolled in the study, 67 (25.9%) had an unfavorable evolution, dying or requiring ICU admission. Comparative analyzes between different glucocorticoids treatments and the association with ICU admission or death were: glucocorticoids treatment (any dose) versus no glucocorticoids treatment (OR: 0.71 [0.30-1.66]), treatment with glucocorticoids (≥250mg prednisone daily) versus no glucocorticoids treatment (OR: 0.35 [0.11-1.08]) and glucocorticoids treatment (≥250mg prednisone daily) versus patients with glucocorticoids doses <250mg prednisone daily or without glucocorticoids treatment (OR: 0.30 [0.10-0.88]). CONCLUSION: The results of this study show that patients with severe SARS-CoV-2 pneumonia treated with glucocorticoids pulses with equivalent doses of prednisone greater than or equal to 250mg have a more favorable evolution (less mortality and less admission to ICU).


Assuntos
Anti-Inflamatórios/uso terapêutico , Tratamento Farmacológico da COVID-19 , Glucocorticoides/uso terapêutico , Adolescente , Adulto , Idoso , COVID-19/complicações , COVID-19/mortalidade , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Hospitalização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
18.
Polymers (Basel) ; 14(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35012137

RESUMO

Stimuli-responsive microgels have recently attracted great attention in fundamental research as their soft particles can be deformed and compressed at high packing fractions resulting in singular phase behaviours. Moreover, they are also well suited for a wide variety of applications such as drug delivery, tissue engineering, organ-on-chip devices, microlenses fabrication and cultural heritage. Here, thermoresponsive and pH-sensitive cross-linked microgels, composed of interpenetrating polymer networks of poly(N-isopropylacrylamide) (PNIPAM) and poly(acrylic acid) (PAAc), are synthesized by a precipitation polymerization method in water and investigated through differential scanning calorimetry in a temperature range across the volume phase transition temperature of PNIPAM microgels. The phase behaviour is studied as a function of heating/cooling rate, concentration, pH and PAAc content. At low concentrations and PAAc contents, the network interpenetration does not affect the transition temperature typical of PNIPAM microgel in agreement with previous studies; on the contrary, we show that it induces a marked decrease at higher concentrations. DSC analysis also reveals an increase of the overall calorimetric enthalpy with increasing concentration and a decrease with increasing PAAc content. These findings are discussed and explained as related to emerging aggregation processes that can be finely controlled by properly changing concentration, PAAc content an pH. A deep analysis of the thermodynamic parameters allows to draw a temperature-concentration state diagram in the investigated concentration range.

19.
ACS Appl Polym Mater ; 2(7): 2791-2801, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32685926

RESUMO

Microgel particles have emerged in the past few years as a favorite model system for fundamental science and for innovative applications ranging from the industrial to biomedical fields. Despite their potentialities, no works so far have focused on the application of microgels for cultural heritage preservation. Here we show their first use for this purpose, focusing on wet paper cleaning. Exploiting their retentive properties, microgels are able to clean paper, ensuring more controlled water release from the gel matrix, in analogy to their macroscopic counterpart, i.e., hydrogels. However, differently from these, the reduced size of microgels makes them suitable to efficiently penetrate in the porous structure of the paper and to easily adapt to the irregular surfaces of the artifacts. To test their cleaning abilities, we prepare microgels made of Gellan gum, a natural and widespread material already used as a hydrogel for paper cleaning, and apply them to modern and ancient paper samples. Combining several diagnostic methods, we show that microgels performances in the removal of cellulose degradation byproducts for ancient samples are superior to commonly employed hydrogels and water bath treatments. This is due to the composition and morphology of ancient paper, which facilitates microgels penetration. For modern paper cleaning, performances are at least comparable to the other methods. In all cases, the application of microgels takes place on a time scale of a few minutes, opening the way for widespread use as a rapid and efficient cleaning protocol.

20.
Int J Gynecol Cancer ; 30(9): 1285-1291, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32571891

RESUMO

OBJECTIVE: This study aimed to analyze the prognostic factors for overall and progression-free survival in patients with vulvar cancer. METHODS: This international, multicenter, retrospective study included 2453 patients diagnosed with vulvar cancer at 100 different institutions. Inclusion criteria were institutional review board approval from each collaborating center, pathologic diagnosis of invasive carcinoma of the vulva, and primary treatment performed at the participating center. Patients with intraepithelial neoplasia or primary treatment at non-participating centers were excluded. Global survival analysis and squamous cell histology subanalysis was performed. RESULTS: After excluding patients due to incomplete data entry, 1727 patients treated for vulvar cancer between January 2001 and December 2005 were registered for analysis (1535 squamous, 42 melanomas, 38 Paget's disease and 112 other histologic types). Melanomas had the worse prognosis (p=0.02). In squamous vulvar tumors, independent factors for increase in local recurrence of vulvar cancer were: no prior radiotherapy (p<0.001) or chemotherapy (p=0.006), and for distant recurrence were the number of positive inguinal nodes (p=0.025), and not having undergone lymphadenectomy (p=0.03) or radiotherapy (p<0.001), with a HR of 1.1 (95% CI 1.2 to 1.21), 2.9 (95% CI 1.4 to 6.1), and 3.1 (95% CI 1.7 to 5.7), respectively. Number of positive nodes (p=0.008), FIGO stage (p<0.001), adjuvant chemotherapy (p=0.001), tumor resection margins (p=0.045), and stromal invasion >5 mm (p=0.001) were correlated with poor overall survival, and large case volume (≥9 vs <9 cases per year) correlated with more favorable overall survival (p=0.05). CONCLUSIONS: Advanced patient age, number of positive inguinal lymph nodes, and lack of adjuvant treatment are significantly associated with a higher risk of relapse in patients with squamous cell vulvar cancer. Case volume per treating institution, FIGO stage, and stromal invasion appear to impact overall survival significantly. Future prospective trials are warranted to establish these prognostic factors for vulvar cancer.


Assuntos
Neoplasias Vulvares/epidemiologia , Neoplasias Vulvares/mortalidade , Idoso , Feminino , Humanos , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
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