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1.
J Endocrinol Invest ; 46(9): 1875-1880, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36870015

RESUMO

BACKGROUND AND AIMS: Retinal sensitivity (RS) and gaze fixation (GF) assessed by retinal microperimetry are useful and complementary tools for identifying mild cognitive impairment (MCI) in patients with type 2 diabetes (T2D). The hypothesis is that RS and GF examine different neural circuits: RS depends only on the visual pathway while GF reflects white matter complex connectivity networks. The aim of the study is to shed light to this issue by examining the relationship of these two parameters with visual evoked potentials (VEP), the current gold standard to examine the visual pathway. MATERIALS AND METHODS: Consecutive T2D patients > 65 years were recruited from the outpatient clinic. Retinal microperimetry (MAIA 3rd generation) and visual evoked potentials (VEP) (Nicolet Viking ED). RS (dB), GF (BCEA63%, BCEA95%) (MAIA) and VEP (Latency P100ms, Amplitude75-100 uV) were analyzed. RESULTS: Thirty three patients (45% women, 72.1 ± 4.6 years) were included. VEP parameters significantly correlated with RS but not with GF. CONCLUSIONS: These results confirm that RS but not GF depends on the visual pathway, reinforcing the concept that they are complementary diagnostic tools. Used together can further increase the value of microperimetry as screening test for identifying T2D population with cognitive impairment.


Assuntos
Diabetes Mellitus Tipo 2 , Testes de Campo Visual , Humanos , Feminino , Masculino , Testes de Campo Visual/métodos , Campos Visuais , Diabetes Mellitus Tipo 2/complicações , Potenciais Evocados Visuais , Retina
2.
Obes Surg ; 33(4): 1211-1217, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36849786

RESUMO

BACKGROUND: Bariatric surgery (BS) has a significant impact on body composition. The purpose of the study is to evaluate the usefulness of musculoskeletal ultrasound (MUS) to bioelectrical impedance (BIA) in the follow-up of patients undergoing BS in terms of body composition and quality of life (QoL). METHODS: This is a prospective pilot study including 32 subjects (75% female, mean age: 49.15 ± 1.9 years) who underwent BS. Fat mass (FM), lean mass (LM), and skeletal muscle index (SMI) were calculated by BIA. MUS measured subcutaneous fat (SF) and thigh muscle thickness (TMT) of the quadriceps. QoL was assessed by the Moorehead-Ardelt questionnaire. All these measurements were performed 1 month prior to BS and at 12-month follow-up. RESULTS: The mean BMI decreased by 6.63 ± 1.25 kg/m2 (p=0.001). We observed significant reductions in FM (p=0.001) and SF (p=0.007) and in LM (p=0.001) but not in SMI and TMT. We found a correlation between the FM and SF (pre-surgical, r=0.42, p=0.01; post-surgical, r=0.52, p=0.003) and between SMI and TMT (pre-surgical, r=0.35, p=0.04; post-surgical, r=0.38, p=0.03). QoL test showed significant improvement (p=0.001). In addition, a correlation between the QoL questionnaire and TMT post-surgery (r=0.91, p=0.019) was observed. However, we did not find any statistically significant correlation between QoL assessment and SMI or LM. CONCLUSIONS: Our results suggest that MUS can be complementary to BIA for the evaluation and the follow-up of body composition after BS. TMT of quadriceps can provide relevant information about regional sarcopenia and has a significant correlation with QoL.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Qualidade de Vida , Projetos Piloto , Obesidade Mórbida/cirurgia , Estudos Prospectivos , Composição Corporal/fisiologia , Cirurgia Bariátrica/métodos , Índice de Massa Corporal , Impedância Elétrica
4.
J Laryngol Otol ; 137(5): 570-576, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35871798

RESUMO

OBJECTIVE: Numerous factors are considered to impact on the rate of complications during salvage total laryngectomy procedures. Neck dissection could be one of these factors. This study analysed the pattern of lymph node metastasis and rate of occult neck disease during salvage total laryngectomy as well as the impact of neck dissection on survival and complication rates. METHOD: This was a retrospective analysis of a prospectively maintained laryngectomy database in two large tertiary teaching hospitals. RESULTS: The rate of occult neck disease was 11.1 per cent. Most cases with occult neck disease had rT4 disease. Patients with complications, advanced tumour stage and positive margins had a significant decrease in overall survival. Patients receiving elective neck dissection did not have any survival benefit. Positron emission tomography-computed tomography showed a very high specificity and negative predictive value. CONCLUSION: According to the low risk of occult neck disease when using contemporary imaging techniques as well as the lack of impact on survival, conservative management of the neck should be considered for crT1-T3 recurrence.


Assuntos
Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/patologia , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia , Esvaziamento Cervical/métodos , Hospitais de Ensino , Laringectomia/efeitos adversos , Laringectomia/métodos , Terapia de Salvação/métodos
5.
J Laryngol Otol ; 136(12): 1231-1236, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35189991

RESUMO

BACKGROUND: The introduction of transoral robotic surgery into routine management of patients is complex. It involves organisational, logistical and clinical challenges. This study presents our experience of implementing such a programme and provides a blueprint for other centres willing to establish similar services. METHODS: Implementation of the robotic surgery programme focused on several key domains: training, logistics, governance, multidisciplinary team awareness, pre-operative imaging, anaesthesia, post-operative care, finance, patient selection and consent. Programme outcomes were evaluated by assessing operative outcomes of the first 117 procedures performed. RESULTS: The success of the transoral robotic surgery programme has been possible because of the scrupulous planning phase before the first procedure, and the time invested on team awareness and training. CONCLUSION: Implementation of a new transoral robotic surgery service has led to: the development of a dedicated transoral robotic surgery patient care protocol, the performance of progressively more complex procedures, the inclusion of transoral robotic surgery training and the establishment of several research projects.


Assuntos
Neoplasias de Cabeça e Pescoço , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias de Cabeça e Pescoço/cirurgia , Reino Unido
6.
Int J Infect Dis ; 110: 426-432, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34332083

RESUMO

OBJECTIVES: To characterize high-risk HPV types associated with cervical precancerous lesions in women living in Yaounde, Cameroon, and to determine their distribution with HIV status. METHODS: Women with abnormal pap smears recorded from February 2015 to May 2019 at Saint Martin de Porres' Health Centre, Yaounde, Cameroon, were recruited in this study after obtaining informed consent. Pap smears were collected and re-examined. Human immunodeficiency virus (HIV) serology was determined. HPV16, 18, 33, and 45 were assessed using standard PCR. RESULTS: All included participants (370) were HPV-positive and had either low grade squamous intraepithelial lesions (67.03%) or high grade squamous intraepithelial lesions (31.35%). They were subdivided into HIV-positive (N =102) and HIV-negative (N =268). In the HIV-negative subgroup, we observed 66.04% HPV16-positve, 41.79% HPV18-positve, 21.27% HPV33-positve and 8.21% HPV45-positve. In the HIV-positive subgroup, we observed 22.55% HPV16-positve, 5.88% HPV18-positve, 75.49% HPV33-positve, and 49.02% HPV45-positve. Married HIV-positive participants (47.14 ± 1.19) were older than both their single counterparts (34.94±1.22, P = 0.0008) and HIV-negative participants (41.43 ± 0.79, P = 0.0001). Single HIV-positive women reported higher numbers of miscarriages (P = 0.0023), and had later first sexual intercourse than HIV-negative (P = 0.0079) women. CONCLUSION: Our study suggested differential expressions in high-risk HPV types with HIV status and cervical precancerous lesions and warrants more extensive studies.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Lesões Pré-Cancerosas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Camarões/epidemiologia , Feminino , Genótipo , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Lesões Pré-Cancerosas/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Displasia do Colo do Útero/epidemiologia
7.
J Laryngol Otol ; 135(2): 168-172, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33517925

RESUMO

OBJECTIVE: The coronavirus disease 2019 pandemic resulted in the cessation of elective surgery. The continued provision of complex head and neck cancer surgery was extremely variable, with some UK centres not performing any cancer surgery. During the pandemic, Guy's and St Thomas' NHS Foundation Trust received high numbers of coronavirus disease 2019 admissions. This paper presents our experience of elective complex major head and neck cancer surgery throughout the pandemic. METHODS: A head and neck cancer surgery hub was set up that provided a co-ordinated managed care pathway for cancer patients during the pandemic; the Guy's Cancer Centre provided a separate, self-enclosed coronavirus-free environment within the hospital campus. RESULTS: Sixty-nine head and neck cancer patients were operated on in two months, and 13 patients had a microvascular free tissue transfer. Nosocomial infection with coronavirus disease 2019 was detected in two cases (3 per cent), neither required critical care unit admission. Both patients made a complete recovery and were discharged home. There were no deaths. CONCLUSION: Performing major head and neck surgery, including free flap surgery, is possible during the pandemic; however, significant changes to conventional practice are required to achieve desirable patient outcomes.


Assuntos
COVID-19/epidemiologia , Infecção Hospitalar/epidemiologia , Neoplasias de Cabeça e Pescoço/cirurgia , Procedimentos Cirúrgicos Otorrinolaringológicos , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Retalhos de Tecido Biológico , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Hemorragia Pós-Operatória/epidemiologia , SARS-CoV-2 , Infecção da Ferida Cirúrgica/epidemiologia , Reino Unido/epidemiologia , Adulto Jovem
8.
J Laryngol Otol ; : 1-10, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33143760

RESUMO

OBJECTIVES: Tracheostomy for coronavirus disease 2019 pneumonitis patients requiring prolonged invasive mechanical ventilation remains a matter of debate. This study analysed the timing and outcomes of percutaneous tracheostomy, and reports our experience of a dedicated ENT-anaesthetics department led tracheostomy team. METHOD: A prospective single-centre observational study was conducted of patients undergoing tracheostomy, who had been diagnosed with coronavirus disease 2019 pneumonitis, between 21st March and 20th May 2020. RESULTS: Eighty-one patients underwent tracheostomy after a median (interquartile range) of 16 (13-20) days of invasive mechanical ventilation. Median follow-up duration was 32 (23-40) days. Of patients, 86.7 per cent were successfully liberated from invasive mechanical ventilation in a median (interquartile range) of 12 (7-16) days. Moreover, 68.7 per cent were subsequently discharged from hospital. On univariate analysis, there was no difference in outcomes between early (before day 14) and late (day 14 or later) tracheostomy. The mortality rate was 8.6 per cent and no deaths were tracheostomy related. CONCLUSION: Outcomes appear favourable when patients are carefully selected. Percutaneous tracheostomy performed via a multidisciplinary approach, with appropriate training, was safe and optimised healthcare resource utilisation.

9.
J Laryngol Otol ; : 1-8, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32873344

RESUMO

OBJECTIVE: The global coronavirus disease 2019 (COVID-19) pandemic has necessitated rapid alterations to diagnostic pathways for head and neck cancer patients that aim to reduce risk to patients (exposure to the hospital environment) and staff (aerosol-generating procedures). Transoral fine needle aspiration cytology offers a low-risk means of rapidly diagnosing patients with oral cavity or oropharyngeal lesions. The technique was utilised in selected patients at our institution during the pandemic. The outcomes are considered in this study. METHOD: Diagnostic outcomes were retrospectively evaluated for a series of patients undergoing transoral fine needle aspiration cytology of oral cavity and oropharyngeal lesions during the COVID-19 pandemic. RESULTS: Five patients underwent transoral fine needle aspiration cytology, yielding lesional material in 100 per cent, with cell blocks providing additional information. In one case, excision biopsy of a lymphoproliferative lesion was required for final diagnosis. CONCLUSION: Transoral fine needle aspiration cytology can provide rapid diagnosis in patients with oral cavity and oropharyngeal lesions. Whilst limitations exist (including tolerability and lesion location), the technique offers significant advantages pertinent to the COVID-19 era, and could be employed in the future to obviate diagnostic surgery in selected patients.

10.
Radiother Oncol ; 145: 146-153, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31981964

RESUMO

PURPOSE: To evaluate whether the 8th staging system is a better discriminator of overall survival (OS) than the 7th edition for oropharyngeal cancer patients after definitive (chemo)radiotherapy (CRT). MATERIAL AND METHODS: Data from oropharyngeal cancer patients treated with CRT with curative intent between 2010 and 2016 at Guy's and St Thomas' Hospitals were reviewed. Human papillomavirus (HPV) status was ascertained in all cases. Patients were staged using the 7th edition and the 8th edition TNM staging system. Demographics, tumor characteristics and treatment response data were included in univariate and multivariate analysis for OS. OS and disease-free survival (DFS) were estimated using the Kaplan-Meier method. In addition, a multivariate survival Cox regression analysis of several clinical variables was performed. RESULTS: A total of 273 patients were included. The median follow-up was 4.7 years. Overall 63 patients died. In multivariate analysis, HPV status, complete response at 3 months and ≤21 units/week alcohol were prognostic for OS. For the entire cohort, the 5-year OS and DFS rates were 78.1% (95% confidence interval CI 0.719-0.831) and 73.9% (95% CI 0.677-0.792), respectively. Better stratification of OS and DFS was recorded by 8th edition for the entire cohort. In HPV-positive cases, risk stratification based on tobacco smoking and nodal stage resulted in statistically higher discrimination in OS rates (5-year OS 90.7% in low risk patients and 84.6% in intermediate risk, p = 0.05) and DFS rates (5-year DFS 91.5% in low risk and 76.1% in intermediate risk, p = 0.001). CONCLUSION: The 8th edition TNM staging system provides better OS stratification in oropharyngeal cancer after definitive CRT compared with the 7th edition. Other clinical variables, such as complete response at 3 months, alcohol and tobacco smoking, should also be considered in future classifications as they provide additional risk stratification information in both HPV-positive and HPV-negative disease.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Humanos , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/terapia , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
11.
Eur J Surg Oncol ; 46(5): 754-762, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31952928

RESUMO

With improved understanding of the biology of differentiated thyroid carcinoma its management is evolving. The approach to surgery for the primary tumour and elective nodal surgery is moving from a "one-size-fits-all" recommendation to a more personalised approach based on risk group stratification. With this selective approach to initial surgery, the indications for adjuvant radioactive iodine (RAI) therapy are also changing. This selective approach to adjuvant therapy requires understanding by the entire treatment team of the rationale for RAI, the potential for benefit, the limitations of the evidence, and the potential for side-effects. This review considers the evidence base for the benefits of using RAI in the primary and recurrent setting as well as the side-effects and risks from RAI treatment. By considering the pros and cons of adjuvant therapy we present an oncologic surgical perspective on selection of treatment for patients, both following pre-operative diagnostic biopsy and in the setting of a post-operative diagnosis of malignancy.


Assuntos
Adenocarcinoma Folicular/radioterapia , Radioisótopos do Iodo/uso terapêutico , Radioterapia Adjuvante , Câncer Papilífero da Tireoide/radioterapia , Neoplasias da Glândula Tireoide/radioterapia , Tireoidectomia , Adenocarcinoma Folicular/patologia , Intervalo Livre de Doença , Humanos , Margens de Excisão , Invasividade Neoplásica , Recidiva Local de Neoplasia , Seleção de Pacientes , Oncologia Cirúrgica , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia
12.
Br J Oral Maxillofac Surg ; 57(10): 1039-1043, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31564483

RESUMO

To validate the use of neck dissection as part of the management of patients with parotid carcinomas, we retrospectively reviewed pathological and clinical data from the head and neck pathology archive at Guy's and St Thomas' Hospital on all patients who had primary parotid carcinomas resected between 1992 and 2014. The main outcome measure was the incidence of metastatic disease. A total of 54 of the 82 patients identified had neck dissections. Nodal metastases were detected in 10 with high-grade, invasive carcinoma ex-pleomorphic adenomas, two with salivary duct carcinomas, one with a high-grade adenocarcinoma not otherwise specified (NOS), one with an adenoid cystic carcinoma, and one with a high-grade acinic cell carcinoma. No metastases were found in those with a low-grade acinic cell carcinoma, low-grade mucoepidermoid carcinoma, epithelial-myoepithelial carcinoma, or non-invasive carcinoma ex-pleomorphic adenoma. The findings of this study support the use of routine neck dissection for the treatment of high-grade, invasive carcinoma ex-pleomorphic adenoma, salivary duct carcinoma, high-grade adenocarcinoma NOS, adenoid cystic carcinoma, and high-grade acinic cell carcinoma.


Assuntos
Adenoma Pleomorfo , Carcinoma Adenoide Cístico , Esvaziamento Cervical , Neoplasias das Glândulas Salivares , Adenoma Pleomorfo/cirurgia , Carcinoma Adenoide Cístico/cirurgia , Humanos , Glândula Parótida/cirurgia , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/cirurgia
13.
BJS Open ; 3(2): 174-179, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30957064

RESUMO

Background: Sternotomy and lateral thoracotomy are required infrequently to remove an intrathoracic goitre (ITG). As few studies have explored the need for an extracervical approach (ECA), the aim of this study was to examine this in a large cohort of patients. Methods: A prospective database of all patients who had surgery for ITG between 2004 and 2016 was interrogated. Patient demographics, preoperative characteristics and type of operation were analysed to identify factors associated with an ECA. Results: Of 237 patients who had surgery for ITG, 29 (12·2 per cent) required an ECA. ITGs below the aortic arch (odds ratio (OR) 10·84; P = 0·004), those with an iceberg shape (OR 59·30; P < 0·001) and revisional surgery (OR 4·83; P = 0·022) were significant preoperative predictors of an ECA. Conclusion: The extent of intrathoracic extension in relation to the aortic arch, iceberg goitre shape and revisional surgery were independent risk factors for ECA. Careful preoperative assessment should take these factors into consideration when determining the optimal surgical approach to ITG.


Assuntos
Bócio Subesternal/cirurgia , Esternotomia/métodos , Toracotomia/métodos , Tireoidectomia/métodos , Idoso , Aorta Torácica/diagnóstico por imagem , Tomada de Decisão Clínica , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Feminino , Bócio Subesternal/diagnóstico , Humanos , Laringoscopia , Funções Verossimilhança , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Período Pré-Operatório , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Esternotomia/estatística & dados numéricos , Toracotomia/estatística & dados numéricos , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Tireoidectomia/estatística & dados numéricos
14.
J Endocrinol Invest ; 42(8): 881-888, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30788770

RESUMO

BACKGROUND: Depressive disorder encompasses a wide spectrum of somatic and psychological symptoms. It is not known whether there are differences regarding the cluster of depressive symptomatology between subjects with depression with and without T2DM. PURPOSE: To explore whether the cluster of depression that prevails among depressive subjects with T2DM differs from individuals with depression, but without T2DM. METHODS: 87 T2DM patients with a pathological Beck Depression Inventory test (BDI) were compared with 50 age- and gender-matched individuals with a major depressive disorder. All 21 items expressed in the BDI were compared between the two groups. RESULTS: The score obtained after administering the BDI was comparable between patients with T2DM and significant depressive symptoms and the control group (18.8 ± 2.7 vs 18.9 ± 3.4; p = 0.9). Subjects with T2DM had higher scores compared with the control group in the following items: sadness (1.4 ± 0.9 vs 0.9 ± 0.9; p = 0.011), difficulty in concentration (1.3 ± 0.8 vs 0.8 ± 0.8; p = 0.01), indecisiveness (1.1 ± 0.8 vs 0.5 ± 0.9; p = 0.012), worries about their health (1.3 ± 0.9 vs 0.6 ± 0.9; p < 0.0001), fatigue (1.2 ± 0.6 vs 0.8 ± 0.7; p = 0.003) and loss of sexual appetite (2.7 ± 0.6 vs 1.2 ± 1.3; p = 0.0001). Suicidal ideation was significantly lower among subjects with T2DM compared with the control group (0.1 ± 0.3 vs 0.6 ± 0.8; p = 0.0001). CONCLUSIONS: Subjects with T2DM and a positive screening for depression presented a different cluster of depression compared with depressed subjects without T2DM, with a predominance of somatic-biological depressive symptoms rather than psychological-cognitive cluster and negative emotions, such as suicidal ideation.


Assuntos
Sintomas Afetivos/etiologia , Depressão/classificação , Transtorno Depressivo Maior/etiologia , Diabetes Mellitus Tipo 2/complicações , Adulto , Estudos de Casos e Controles , Depressão/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
17.
Sci Rep ; 8(1): 6109, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29666448

RESUMO

Atmospheric new particle formation (NPF) and growth significantly influences the indirect aerosol-cloud effect within the polar climate system. In this work, the aerosol population is categorised via cluster analysis of aerosol number size distributions (9-915 nm, 65 bins) taken at Villum Research Station, Station Nord (VRS) in North Greenland during a 7 year record (2010-2016). Data are clustered at daily averaged resolution; in total, we classified six categories, five of which clearly describe the ultrafine aerosol population, one of which is linked to nucleation events (up to 39% during summer). Air mass trajectory analyses tie these frequent nucleation events to biogenic precursors released by open water and melting sea ice regions. NPF events in the studied regions seem not to be related to bird colonies from coastal zones. Our results show a negative correlation (r = -0.89) between NPF events and sea ice extent, suggesting the impact of ultrafine Arctic aerosols is likely to increase in the future, given the likely increased sea ice melting. Understanding the composition and the sources of Arctic aerosols requires further integrated studies with joint multi-component ocean-atmosphere observation and modelling.

18.
Sci Rep ; 8(1): 1482, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29367716

RESUMO

The formation of new atmospheric particles involves an initial step forming stable clusters less than a nanometre in size (<~1 nm), followed by growth into quasi-stable aerosol particles a few nanometres (~1-10 nm) and larger (>~10 nm). Although at times, the same species can be responsible for both processes, it is thought that more generally each step comprises differing chemical contributors. Here, we present a novel analysis of measurements from a unique multi-station ground-based observing system which reveals new insights into continental-scale patterns associated with new particle formation. Statistical cluster analysis of this unique 2-year multi-station dataset comprising size distribution and chemical composition reveals that across Europe, there are different major seasonal trends depending on geographical location, concomitant with diversity in nucleating species while it seems that the growth phase is dominated by organic aerosol formation. The diversity and seasonality of these events requires an advanced observing system to elucidate the key processes and species driving particle formation, along with detecting continental scale changes in aerosol formation into the future.

19.
Sci Rep ; 7(1): 3318, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28607400

RESUMO

Atmospheric new particle formation (NPF) and growth significantly influences climate by supplying new seeds for cloud condensation and brightness. Currently, there is a lack of understanding of whether and how marine biota emissions affect aerosol-cloud-climate interactions in the Arctic. Here, the aerosol population was categorised via cluster analysis of aerosol size distributions taken at Mt Zeppelin (Svalbard) during a 11 year record. The daily temporal occurrence of NPF events likely caused by nucleation in the polar marine boundary layer was quantified annually as 18%, with a peak of 51% during summer months. Air mass trajectory analysis and atmospheric nitrogen and sulphur tracers link these frequent nucleation events to biogenic precursors released by open water and melting sea ice regions. The occurrence of such events across a full decade was anti-correlated with sea ice extent. New particles originating from open water and open pack ice increased the cloud condensation nuclei concentration background by at least ca. 20%, supporting a marine biosphere-climate link through sea ice melt and low altitude clouds that may have contributed to accelerate Arctic warming. Our results prompt a better representation of biogenic aerosol sources in Arctic climate models.

20.
J Endocrinol Invest ; 40(9): 925-935, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28357783

RESUMO

Diabetic retinopathy (DR) is the leading cause of visual impairment and preventable blindness and represents a significant socioeconomic cost for healthcare systems worldwide. In early stages of DR the only therapeutic strategy that physicians can offer is a tight control of the risk factors for DR (mainly blood glucose and blood pressure). The currently available treatments for DR are applicable only at advanced stages of the disease and are associated with significant adverse effects. Therefore, new treatments for the early stages of DR are needed. However, in early stages of DR invasive treatments such as intravitreal injections are too aggressive, and topical treatment seems to be an emerging route. In the present review, therapeutic strategies based on the main pathogenic mechanisms involved in the development of DR are reviewed. The main gap in the clinical setting is the treatment of early stages of DR and, therefore, this review emphasizes in this issue by giving an overview of potential druggable targets. By understanding of disease-specific pathogenic mechanisms, biological heterogeneity and progression patterns in early and advanced DR a more personalised approach to patient treatment will be implemented.


Assuntos
Retinopatia Diabética/metabolismo , Retinopatia Diabética/terapia , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Retinopatia Diabética/diagnóstico , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Microcirculação/efeitos dos fármacos , Microcirculação/fisiologia , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/terapia , Fatores de Risco
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