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1.
Diabetes Metab ; 46(3): 203-209, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31816431

RESUMO

AIMS: Copeptin, a surrogate of vasopressin, is elevated in type 1 diabetes (T1D) and predicts kidney disease and cardiovascular mortality. Given the cardiorenal protective effects of SGLT2 inhibition (SGLT2i), our aim was to examine: 1) the relationship between serum copeptin, metabolic, renal and systemic hemodynamic parameters in adults with T1D; and 2) serum copeptin after SGLT2i with empagliflozin. MATERIALS AND METHODS: In this post-hoc, exploratory analysis, serum copeptin, glomerular filtration rate (GFRInulin), effective renal plasma flow (ERPFPAH), plasma renin angiotensin aldosterone system markers, HbA1c, 24-hour urine volume and sodium excretion were measured in 40 participants with T1D (24.3±5.1 years) during eu- and hyperglycaemia before and after 8 weeks of 25mg of daily empagliflozin. RESULTS: Higher baseline copeptin correlated with higher HbA1c, lower 24-hour urine volume and sodium excretion, after correcting for age, sex, systolic blood pressure, and HbA1c. Copeptin concentrations increased in response to empagliflozin under euglycaemia (4.1±2.1 to 5.1±2.8pmol/L, P=0.0053) and hyperglycaemia (3.3±1.4 to 5.6±2.8pmol/L, P<0.0001). The rise in copeptin in response to empagliflozin correlated with change in 24-hour urine volume, but was independent of changes in fractional excretion of sodium and haematocrit. CONCLUSIONS: Elevated serum copeptin was associated with worse glycaemic control and lower diuresis and natriuresis. SGLT2i increased serum copeptin in adults with T1D, and the rise correlated with change in diuresis, but not natriuresis and hemo-concentration. Further work is required to evaluate the clinical implications of elevated copeptin with SGLT2i, including whether it is simply a marker of diuresis or may contribute to cardiorenal disease long-term.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Glicopeptídeos/sangue , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Adulto , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Hemoglobinas Glicadas/análise , Controle Glicêmico , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Masculino , Natriurese/efeitos dos fármacos , Natriurese/fisiologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Adulto Jovem
2.
Toxicol Lett ; 294: 135-144, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29778911

RESUMO

Di(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer that is metabolized to mono(2-ethylhexyl) phthalate (MEHP). Inhalation is an important exposure route for both phthalates, and their effects on lungs include inflammation, alteration of postnatal maturation (alveolarization), enlarged airspaces and cell differentiation changes, suggesting that alveolar epithelial cells-2 (AEC) are targets of phthalates. This study evaluated the cell progression, epithelial and mesenchymal markers, including surfactant secretion in A549 cells (AEC) that were exposed to DEHP (1-100 µM) or MEHP (1-50 µM) for 24-72 h. The results showed an increased cell proliferation at all concentrations of each phthalate at 24 and 48 h. Cell migration showed a concentration-dependent increase at 24 and 48 h of exposure to either phthalate and enlarged structures were seen. Decreased levels of both surfactants (SP-B/SP-C) were observed after the exposure to either phthalate at 48 h, and of SP-C positive cells exposed to MEHP, suggesting a loss of the epithelial phenotype. While a decrease in the epithelial marker E-cadherin and an increase in the mesenchymal marker fibronectin were observed following exposure to either phthalate. Our results showed that DEHP and MEHP altered the structure and migration of A549 cells and promoted the loss of the epithelial phenotype.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Desdiferenciação Celular/efeitos dos fármacos , Dietilexilftalato/análogos & derivados , Dietilexilftalato/toxicidade , Plastificantes/toxicidade , Proteína B Associada a Surfactante Pulmonar/antagonistas & inibidores , Proteína C Associada a Surfactante Pulmonar/antagonistas & inibidores , Células A549 , Células Epiteliais Alveolares/citologia , Células Epiteliais Alveolares/metabolismo , Antígenos CD , Biomarcadores/metabolismo , Caderinas/antagonistas & inibidores , Caderinas/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibronectinas/agonistas , Fibronectinas/metabolismo , Humanos , Cinética , Proteína B Associada a Surfactante Pulmonar/metabolismo , Proteína C Associada a Surfactante Pulmonar/metabolismo
3.
Eur J Neurol ; 25(3): 484-490, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29194856

RESUMO

BACKGROUND AND PURPOSE: The Toronto Clinical Neuropathy Score (TCNS) is a valid and reliable scale for the diagnosis and staging of diabetic sensorimotor polyneuropathy. In this study, we aimed to explore the performance of the TCNS in non-diabetic polyneuropathies. METHODS: We performed a prospective study from November 2016 to May 2017 of patients with non-diabetic polyneuropathy. Patients had clinical, electrophysiological and functional assessments of their polyneuropathy, and the findings were correlated with the TCNS. RESULTS: The TCNS correlated with all clinical, electrophysiological and disability measures of polyneuropathy, mostly at a moderate level (e.g. r = -0.58 for sural nerve action potential amplitude). Higher TCNS severity grades were associated with worse polyneuropathy on all measures in the lower limbs, and with worse electrophysiological parameters and vibration perception thresholds in the upper limbs. The scale also showed excellent reliability and accuracy (kappa, 0.92-0.93 for inter- and intra-observer reliability; area under the receiver operating characteristics curve, 0.93). CONCLUSION: The TCNS is a valid and reliable scale for a wide spectrum of polyneuropathies, and might be useful in clinical practise and research for the diagnosis and staging of polyneuropathy.


Assuntos
Polineuropatias/diagnóstico , Adulto , Idoso , Avaliação da Deficiência , Fenômenos Eletrofisiológicos , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Variações Dependentes do Observador , Estudos Prospectivos , Qualidade de Vida , Curva ROC , Reprodutibilidade dos Testes
4.
Space Sci Rev ; 214(1)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-30713357

RESUMO

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm2 of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.

5.
Rev Sci Instrum ; 88(3): 033107, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28372390

RESUMO

A sensitive chemical aerosol Raman detector (CARD) has been developed for the trace detection and identification of chemical particles in the ambient atmosphere. CARD includes an improved aerosol concentrator with a concentration factor of about 40 and a CCD camera for improved detection sensitivity. Aerosolized isovanillin, which is relatively safe, has been used to characterize the performance of the CARD. The limit of detection (SNR = 10) for isovanillin in 15 s has been determined to be 1.6 pg/cm3, which corresponds to 6.3 × 109 molecules/cm3 or 0.26 ppb. While less sensitive, CARD can also detect gases. This paper provides a more detailed description of the CARD hardware and detection algorithm than has previously been published.

6.
Br J Anaesth ; 116(1): 18-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26675948

RESUMO

Insulin pump therapy is increasingly common in patients with type 1 diabetes. Many of these patients will require surgery at some point in their lifetime. Few doctors will have experience of managing these patients, and little evidence exists to assist in the development of guidelines for patients with insulin pump therapy, undergoing surgery.It is clear that during emergency surgery insulin pump therapy is not appropriate and should be discontinued, but patients undergoing some elective surgery can and should continue insulin pump therapy, without any adverse effect on their blood sugar control, or on the outcome of their surgery. Individual hospitals need to formalize guidance on the management of patients receiving continuous subcutaneous insulin therapy, to allow patients the choice to continue their therapy during surgery. This expert opinion presents anaesthetists with a suggested clinical framework to help facilitate continued insulin pump therapy, during elective surgery and into the postoperative period.


Assuntos
Anestesia/métodos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Sistemas de Infusão de Insulina , Insulina/uso terapêutico , Humanos , Hipoglicemiantes/uso terapêutico , Período Perioperatório
7.
Diabet Med ; 33(8): 1102-11, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26670339

RESUMO

AIMS: Increased plasma uric acid (PUA) levels are associated with impaired renal function in patients with Type 1 diabetes, but the mechanisms are not well understood. Our aim was to evaluate whether higher PUA levels are associated with increased afferent arteriolar resistance in patients with Type 1 diabetes vs. healthy controls, thereby influencing renal function. METHODS: PUA, GFR (inulin) and effective renal plasma flow (ERPF; para-aminohippurate) were measured in 70 otherwise healthy patients with Type 1 diabetes and 60 healthy controls. Gomez's equations were used to estimate afferent (RA ) and efferent (RE ) arteriolar resistances, glomerular hydrostatic pressure (PGLO ) and filtration pressure (ΔPF ). The relationships between PUA and glomerular haemodynamic parameters were evaluated by univariable linear regression correlation coefficients. RESULTS: In patients with Type 1 diabetes, higher PUA correlated with lower PGLO (P = 0.002) and ΔPF (P = 0.0007), with higher RA (P = 0.001), but not with RE (P = 0.55). These associations were accompanied by correlations between higher PUA with lower GFR (P = 0.0007), ERPF (P = 0.008), RBF (P = 0.047) and higher RVR (P = 0.021). There were no significant correlations between PUA and renal haemodynamic parameters in the healthy controls. CONCLUSIONS: The association between higher PUA with lower GFR and lower ERPF in patients with Type 1 diabetes is driven by alterations in the estimated RA . PUA-mediated RA may be caused by increased tone or thickening of the afferent renal arteriole, which might potentiate renal injury by causing ischaemia to the renal microcirculation.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Pressão Hidrostática , Glomérulos Renais/irrigação sanguínea , Fluxo Plasmático Renal Efetivo , Ácido Úrico/sangue , Resistência Vascular , Adulto , Estudos de Casos e Controles , Feminino , Taxa de Filtração Glomerular , Hemodinâmica , Humanos , Modelos Lineares , Masculino , Adulto Jovem
8.
Diabet Med ; 32(11): 1425-37, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25962798

RESUMO

Although regular physical activity is encouraged for individuals with diabetes, exercise at high altitude increases risk for a number of potential complications. This review highlights our current understanding of the key physiological and clinical issues that accompany high-altitude travel and proposes basic clinical strategies to help overcome obstacles faced by trekkers with Type 1 or Type 2 diabetes. Although individuals with diabetes have adaptations to the hypoxia of high altitude (increased ventilation, heart rate, blood pressure and hormonal responses), elevated counter-regulatory hormones can impair glycaemic control, particularly if mountain sickness occurs. Moreover, high-altitude-induced anorexia and increased energy expenditure can predispose individuals to dysglycaemia unless careful adjustments in medication are performed. Frequent blood glucose monitoring is imperative, and results must be interpreted with caution because capillary blood glucose meter results may be less accurate at high elevations and low temperatures. It is also important to undergo pre-travel screening to rule out possible contraindications owing to chronic diabetes complications and make well-informed decisions about risks. Despite the risks, healthy, physically fit and well-prepared individuals with Type 1 or Type 2 diabetes who are capable of advanced self-management can be encouraged to participate in these activities and attain their summit goals. Moreover, trekking at high altitude can serve as an effective means to engage in physical activity and to increase confidence with fundamental diabetes self-management skills.


Assuntos
Doença da Altitude/prevenção & controle , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Montanhismo , Assunção de Riscos , Autocuidado , Doença da Altitude/complicações , Terapia Combinada , Complicações do Diabetes/complicações , Complicações do Diabetes/diagnóstico , Complicações do Diabetes/fisiopatologia , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Diagnóstico Precoce , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemia/prevenção & controle , Aptidão Física , Medição de Risco
9.
Environ Geochem Health ; 37(3): 545-56, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25537165

RESUMO

Slag, a by-product from the iron and steel industry, has a range of applications within construction and is used in wastewater treatment. Historically considered a waste material, little consideration was given to the environmental impacts of its disposal. South Gare (a Site of Special Scientific Interest) located at the mouth of the Tees estuary, UK, formed on slag deposits used to create a sea wall and make the land behind permanent. Over time, ponds formed in depressions with the water chemistry, being significantly impacted by the slag deposits. Calcium levels reached 504 mg/L, nitrate 49.0 mg/L and sulphate 1,698 mg/L. These levels were also reflected in the composition of the sediment. pH (5.10-9.90) and electrical conductivity (2,710-3,598 µS/cm) were variable but often notably high. Pb, Cu and Cd were not present within the water, whilst Zn ranged from 0.027 to 0.37 mg/L. Heavy metal levels were higher in surface sediments. Zinc was most dominant (174.3-1,310.2 mg/L) followed by Pb (9.9-431 mg/L), Cu (8.4-41.8 mg/L) and Cd (0.4-1.1 mg/L). A sediment core provided a historical overview of the ponds. The ponds were unfavourable for aquatic biodiversity and unsuitable for drinking water abstraction.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Lagoas/química , Poluentes Químicos da Água/análise , Qualidade da Água , Animais , Biodiversidade , Monitoramento Ambiental , Resíduos Industriais/análise , Invertebrados , Reino Unido
11.
Horm Metab Res ; 45(7): 490-4, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23553368

RESUMO

Most studies on the effect of tibolone on the uterus have focused on the endometrium dismissing the importance of the myometrium. The aim of the present study was to investigate some estrogen-like actions of tibolone in the uterus assessed by: 1) the expression of estrogen, progesterone, and serotonin receptors, and 2) the myometrial contraction induced by serotonin. Estradiol (250 µg), progesterone (50 mg), or testosterone (25 mg) pellets were implanted to ovariectomized rats. Tibolone (0.5 mg/day) was orally administered. An implanted pellet containing vehicle or an equivalent volume of water p.o., were used as controls. Sixty days after beginning the treatments, rats were killed and uterus removed. One horn was processed to evaluate estrogen-alpha, progesterone A and B, and serotonin-2A receptors expression, and the other one was used for studying contraction to serotonin and 60 mM potassium solution. The present data showed that tibolone-induced expression of estrogen, progesterone, and serotonin receptors, but did not induce uterine contractile response to either serotonin or potassium solution. These findings suggest that, in the uterus, tibolone may exert molecular estrogenic actions such as the induction of receptor expression, but not a physiological response as the estrogen-dependent contraction to serotonin.


Assuntos
Receptor alfa de Estrogênio/genética , Expressão Gênica/efeitos dos fármacos , Norpregnenos/farmacologia , Receptores de Progesterona/genética , Receptores de Serotonina/genética , Contração Uterina/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Feminino , Ratos , Ratos Sprague-Dawley , Receptores de Progesterona/metabolismo , Receptores de Serotonina/metabolismo , Útero/fisiologia
12.
Diabet Med ; 29(9): e297-303, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22519850

RESUMO

AIM: Corneal confocal microscopy is a promising screening method for diabetic neuropathy. Although much research in this field has been accomplished, we aimed to determine and confirm the known clinical and eyewear variables associated with the parameters of corneal confocal microscopy specifically in healthy volunteers, in particular associations with corneal nerve fibre length. METHODS: Clinical characteristics, electrophysiological examination and a general clinical eye history were collected from 64 healthy volunteers. Corneal confocal microscopy was performed to determine corneal nerve fibre length, corneal nerve branch density, corneal nerve fibre density and tortuosity coefficient. Univariate and multivariate linear regression analysis was used to determine clinical variables associated with corneal nerve fibre length parameters. RESULTS: We observed that corneal nerve fibre length has a broad distribution in healthy volunteers (18 ± 4 mm/mm(2), 95% confidence interval, 12.3-25.7 mm/mm(2)). Multivariate regression analysis demonstrated that HbA(1c) was the only independent clinical factor to account for variations in corneal nerve fibre length, independent of age and status of contact lens wear. CONCLUSIONS: This study does not provide convincing evidence that corneal nerve fibre length is independently associated with age or the wearing of contact lenses, and that these factors are therefore unlikely to hinder valid screening for polyneuropathies such as diabetic neuropathy. Furthermore, the strong inverse association of corneal nerve fibre length with glycaemic exposure may support the use of this parameter to detect subclinical pre-diabetic nerve injury.


Assuntos
Córnea/inervação , Córnea/patologia , Neuropatias Diabéticas/diagnóstico , Programas de Rastreamento/métodos , Microscopia Confocal , Adulto , Biomarcadores/sangue , Estudos Transversais , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/patologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Análise de Regressão
13.
Diabetes Metab Res Rev ; 27(7): 629-38, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21695762

RESUMO

Painful diabetic peripheral neuropathy (DPN) is common, is associated with significant reduction in quality of life and poses major treatment challenges to the practising physician. Although poor glucose control and cardiovascular risk factors have been proven to contribute to the aetiology of DPN, risk factors specific for painful DPN remain unknown. A number of instruments have been tested to assess the character, intensity and impact of painful DPN on quality of life, activities of daily living and mood. Management of the patient with DPN must be tailored to individual requirements, taking into consideration the co-morbidities and other factors. Pharmacological agents with proven efficacy for painful DPN include tricyclic anti-depressants, the selective serotonin and noradrenaline re-uptake inhibitors, anti-convulsants, opiates, membrane stabilizers, the anti-oxidant alpha-lipoic acid and topical agents including capsaicin. Current first-line therapies for painful DPN include tricyclic anti-depressants, the serotonin and noradrenaline re-uptake inhibitor duloxetine and the anti-convulsants pregabalin and gabapentin. When prescribing any of these agents, other co-morbidities and costs must be taken into account. Second-line approaches include the use of opiates such as synthetic opioid tramadol, morphine and oxycodone-controlled release. There is a limited literature with regard to combination treatment. In extreme cases of painful DPN unresponsive to pharmacotherapy, occasional use of electrical spinal cord stimulation might be indicated. There are a number of unmet needs in the therapeutic management of painful DPN. These include the need for randomized controlled trials with active comparators and data on the long-term efficacy of agents used, as most trials have lasted for less than 6 months. Finally, there is a need for appropriately designed studies to investigate non-pharmacological approaches.


Assuntos
Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/tratamento farmacológico , Dor/diagnóstico , Dor/tratamento farmacológico , Atividades Cotidianas , Analgésicos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Antidepressivos/uso terapêutico , Consenso , Gerenciamento Clínico , Humanos , Qualidade de Vida
14.
Neurology ; 76(20): 1758-65, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21482920

RESUMO

OBJECTIVE: To develop a scientifically sound and clinically relevant evidence-based guideline for the treatment of painful diabetic neuropathy (PDN). METHODS: We performed a systematic review of the literature from 1960 to August 2008 and classified the studies according to the American Academy of Neurology classification of evidence scheme for a therapeutic article, and recommendations were linked to the strength of the evidence. The basic question asked was: "What is the efficacy of a given treatment (pharmacologic: anticonvulsants, antidepressants, opioids, others; and nonpharmacologic: electrical stimulation, magnetic field treatment, low-intensity laser treatment, Reiki massage, others) to reduce pain and improve physical function and quality of life (QOL) in patients with PDN?" RESULTS AND RECOMMENDATIONS: Pregabalin is established as effective and should be offered for relief of PDN (Level A). Venlafaxine, duloxetine, amitriptyline, gabapentin, valproate, opioids (morphine sulfate, tramadol, and oxycodone controlled-release), and capsaicin are probably effective and should be considered for treatment of PDN (Level B). Other treatments have less robust evidence or the evidence is negative. Effective treatments for PDN are available, but many have side effects that limit their usefulness, and few studies have sufficient information on treatment effects on function and QOL.


Assuntos
Neuropatias Diabéticas/terapia , Manejo da Dor , Analgésicos Opioides/uso terapêutico , Anticonvulsivantes/uso terapêutico , Antidepressivos/uso terapêutico , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/tratamento farmacológico , Terapia por Estimulação Elétrica , Campos Eletromagnéticos , Medicina Baseada em Evidências , Humanos , Dor/tratamento farmacológico , Dor/etiologia
15.
Diabet Med ; 28(10): 1253-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21434993

RESUMO

AIM: With the goal of identifying a valid biomarker of early diabetic sensorimotor polyneuropathy, we aimed to identify the most reliable in vivo corneal confocal microscopy (CCM) parameter for detection of abnormality of small nerve fibre morphology. METHODS: Cross-sectional examination of 46 subjects (26 with Type 1 diabetes and 20 healthy volunteers) examined by corneal confocal microscopy for intra- and interobserver reproducibility by the intraclass correlation coefficient method. Corneal nerve fibre density, nerve branch density, nerve fibre length and tortuosity were measured on the same day that subjects underwent clinical and electrophysiological examination. RESULTS: The 26 subjects with Type 1 diabetes had mean age and diabetes duration 42.8 ± 16.9 and 22.7 ± 16.4 years, respectively. Twelve of those subjects (46%) did not meet criteria for diabetic sensorimotor polyneuropathy, while five (19%) had mild, three (12%) had moderate and six (23%) had severe diabetic sensorimotor polyneuropathy. None of the healthy volunteers (mean age 41.4 ± 17.3 years) had polyneuropathy. Re-examination of selected corneal confocal microscopy images or sets of 40 images yielded very good to excellent intraclass correlation coefficients for all parameters. However, only one parameter (corneal nerve fibre length) emerged with consistently very good reproducibility using a clinically relevant 'study-level' protocol of subject re-examination (intra-observer intraclass correlation coefficient 0.72; interobserver intraclass correlation coefficient 0.73). Despite no differences in intraclass correlation coefficient between subgroups, corneal nerve fibre length was significantly lower (14.76 vs. 16.15 mm/mm(2), P = 0.04) in those with diabetes. CONCLUSIONS: Development of corneal confocal microscopy may need to focus on the measurement of corneal nerve fibre length, as it appears to have superior reliability in comparison with other parameters, and as evidence exists for its potential as a clinical biomarker of early diabetic sensorimotor polyneuropathy.


Assuntos
Córnea/patologia , Diabetes Mellitus Tipo 1/patologia , Neuropatias Diabéticas/patologia , Microscopia Confocal , Fibras Nervosas/patologia , Adulto , Biomarcadores/sangue , Córnea/inervação , Córnea/fisiopatologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Diagnóstico Precoce , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Microscopia Confocal/métodos , Valores de Referência , Reprodutibilidade dos Testes
16.
Diabet Med ; 27(12): 1358-65, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21059087

RESUMO

AIMS: Systematic study of hyperfiltration in diabetic nephropathy has been hindered by the lack of a simple glomerular filtration rate (GFR) measure that is accurate in this range of renal function. Serum cystatin C (GFR(CYSTATIN C) ) reflects long-term trends in GFR in normal or elevated ranges. To test whether it can reflect acute changes, we examined the impact of clamped hyperglycaemia on GFR(CYSTATIN C) and GFR(INULIN) in subjects with Type 1 diabetes. METHODS: GFR(INULIN) and GFR(CYSTATIN C) were measured in 32 normotensive, normoalbuminuric subjects during clamped euglycaemia and hyperglycaemia. For comparison, GFR(MDRD) was estimated according to the four-variable equation. RESULTS: During clamped euglycaemia, agreement between GFR(CYSTATIN C) and GFR(INULIN) was excellent, with mean bias +1.9 (90% distribution -29 to +31) ml min(-1) 1.73 m(-2), while GFR(MDRD) had mean bias +11.4 (-45 to +51) ml min(-1) 1.73 m(-2). With exposure to clamped hyperglycaemia, the mean increase in GFR(CYSTATIN C) (+17.5 ± 13.5 ml min(-1) 1.73 m(-2) ) reflected that observed with GFR(INULIN) (+15.3 ± 28.1 ml min(-1) 1.73 m(-2), P = 0.74), while GFR(MDRD) demonstrated a mean decline of -4.4 ± 33.6 ml min(-1) 1.73 m(-2) (P = 0.01). In all 24 subjects in whom GFR(INULIN) increased in response to hyperglycaemia, GFR(CYSTATIN C) reflected a concordant change (sensitivity, 100%) while GFR(MDRD) increased in 10/24 (sensitivity, 42%). In the eight remaining subjects, specificity was 25 and 75% for GFR(CYSTATIN C) and GFR(MDRD), respectively. CONCLUSION: GFR(CYSTATIN C) reflects normal and elevated renal function better than GFR(MDRD) even under the acute influences of hyperglycaemia, suggesting a role for cystatin C in clinical practice and research for the study of early renal function changes in Type 1 diabetes.


Assuntos
Biomarcadores/sangue , Creatinina/sangue , Cistatina C/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/fisiopatologia , Taxa de Filtração Glomerular , Hiperglicemia/complicações , Adolescente , Glicemia/fisiologia , Diabetes Mellitus Tipo 1/sangue , Nefropatias Diabéticas/sangue , Progressão da Doença , Feminino , Humanos , Hiperglicemia/sangue , Testes de Função Renal , Masculino
17.
Diabet Med ; 27(11): 1271-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20950385

RESUMO

AIMS: Randomized clinical trials have frequently shown improvement in diabetic sensorimotor polyneuropathy in placebo-treated participants, counter to the prevailing concept that it deteriorates with time. We aimed to determine the variables associated with this paradoxical nerve function improvement. METHODS: Participants with diabetic sensorimotor polyneuropathy randomized to placebo in a multi-centre, double-blind study were evaluated for the primary outcome of 1-year change in the summed sensory nerve conduction velocity of the bilateral sural and non-dominant median nerves. Association with clinical and biochemical variables measured at 13 time points were examined. RESULTS: The 134 participants had mild to moderate diabetic sensorimotor polyneuropathy of 4.6 years' duration and mean 1-year improvement of 2.0 ± 8.0 m/s. Primary outcome measures were available for 122 participants (91%). In multivariate analyses, the change in HbA(1c) and serum triglycerides from baseline to 2 months demonstrated the strongest association, even independent of baseline and end-of-study levels. According to quintiles of change, we determined thresholds: participants with salutary improvement in HbA(1c) (exceeding a drop of -0.8%) or whose triglycerides did not increase (by 0.32 mmol/l or more) experienced significant improvement (2.9 m/s), while those with salutary levels of both these variables had an exaggerated improvement (5.1 m/s). In comparison, those with non-salutary changes in both variables experienced a loss of -4.9 m/s (ANOVA P=0.0014). CONCLUSIONS: In mild to moderate diabetic sensorimotor polyneuropathy, short-term improvements in glycaemic control and serum triglyceride levels have an independent, additive and durable effect on restoration of nerve function.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Hemoglobinas Glicadas/metabolismo , Condução Nervosa/fisiologia , Triglicerídeos/sangue , Adolescente , Adulto , Idoso , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/efeitos dos fármacos , Placebos , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
18.
Clin Exp Allergy ; 39(5): 740-51, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19302253

RESUMO

BACKGROUND: A hallmark of airway remodelling in asthma is subepithelial fibrosis, but its relation with airway dysfunction is still controversial. OBJECTIVE: To describe airway functional abnormalities and subepithelial remodelling induced by repetitive antigenic challenges. METHODS: Nine inhaled antigenic challenges were applied every 10 days to guinea-pigs sensitized to ovalbumin (OVA). Antigen-induced airway hyperresponsiveness (AI-AHR) to histamine and its immunohistopathological relationship was evaluated at the first, third and ninth OVA challenges. RESULTS: From the first challenge on, OVA induced acute transient bronchoobstruction followed by development of AI-AHR. A progressive rise in baseline Penh (a bronchoobstruction index) and granulocyte airway infiltration was also observed. After the ninth OVA challenge, the amount of extracellular matrix in the subepithelial region (SER) of bronchi and bronchioles was increased. Immunohistochemistry analysis showed that this SER fibrosis was associated to beta1-integrin subunit overexpression, even in acellular areas. Immunoelectronmicroscopy corroborated the location of beta1-integrin in extracellular matrix, essentially in types l and II collagen fibres. Presence of alpha1- and alpha2-integrin subunits in these areas was also corroborated. AI-AHR was correlated with degree of SER increment, cell infiltration, and beta1-integrin expression. CONCLUSION: Our data suggested that beta1-integrin shedding produced by repetitive allergen challenges in guinea-pigs was associated with collagen deposition in SER of bronchi and bronchioles, along with inflammatory cells infiltration and AI-AHR development.


Assuntos
Asma/imunologia , Brônquios/imunologia , Integrina beta1/metabolismo , Administração por Inalação , Animais , Asma/patologia , Brônquios/ultraestrutura , Líquido da Lavagem Broncoalveolar/imunologia , Doença Crônica , Colágeno/imunologia , Colágeno/metabolismo , Modelos Animais de Doenças , Matriz Extracelular/imunologia , Matriz Extracelular/metabolismo , Cobaias , Integrina beta1/imunologia , Masculino , Microscopia Imunoeletrônica , Ovalbumina/imunologia
19.
Diabet Med ; 26(3): 240-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19317818

RESUMO

INTRODUCTION: A reliable and valid clinical tool to capture symptoms and signs of diabetic sensorimotor polyneuropathy (DSP) for use in clinical research trials is urgently needed. The validated Toronto Clinical Neuropathy Score (TCNS) was modified to improve sensitivity to early DSP changes. We aimed to assess the reproducibility of this modified tool, the mTCNS and to determine its validity relative to the precursor TCNS. METHODS: Sixty-five patients (six Type 1, 59 Type 2 diabetes) with diabetes duration 13 +/- 8 years were accrued from four study sites and examined on 2 days for internal consistency and inter- and intra-rater reliability of the mTCNS. In the absence of a single quantitative gold-standard measure for DSP, results of the mTCNS were compared with the precursor TCNS for the purpose of estimating validity. RESULTS: Internal consistency of the two domains within the mTCNS was good (Cronbach's alpha 0.78). Very good inter-rater reliability for the mTCNS was demonstrated by an intra-class correlation coefficient for the mTCNS of 0.87 (95% confidence interval, 0.79-0.91), which was similar in magnitude to that of the TCNS (0.83; 95% confidence interval, 0.75-0.89). Intra-rater reliability testing of the mTCNS showed moderate to good correlation for individual symptoms and sensory tests (Cohen's kappa values of 0.54-0.73). The mTCNS shared moderate correlation with the precursor TCNS (Pearson correlation coefficient, 0.58). DISCUSSION: The mTCNS, a clinical score with higher face validity for tracking mild to moderate DSP, has sufficient reliability and validity relative to its precursor TCNS for use in clinical research.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Avaliação da Deficiência , Atividades Cotidianas/psicologia , Adolescente , Adulto , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Inquéritos e Questionários , Adulto Jovem
20.
Gut ; 57(8): 1097-101, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18364438

RESUMO

BACKGROUND AND AIMS: The mismatch repair (MMR) genes are in charge of maintaining genomic integrity. Mutations in the MMR genes are at the origin of a familial form of colorectal cancer (CRC). This syndrome accounts for only a small proportion of the excess familial risk of CRC. The characteristics of the alleles that account for the remainder of cases are unknown. To assess the putative associations between common variants in MMR genes and CRC, we performed a genetic case-control study using a single-nucleotide polymorphism (SNP) tagging approach. PATIENTS AND METHODS: A total of 2299 cases and 2284 unrelated controls were genotyped for 68 tagging SNPs in seven MMR genes (MLH1, MLH3, MSH2, MSH3, MSH6, PMS1 and PMS2). Genotype frequencies were measured in cases and controls and analysed using univariate analysis. Haplotypes were constructed and analysed using logistic regression. We also carried out a two-locus interaction analysis and a global test analysis. RESULTS: Genotype frequencies were found to be marginally different in cases and controls for MSH3 rs26279 with a rare homozygote OR = 1.31 [95% confidence interval (CI) 1.05 to 1.62], p(trend) = 0.04. We found a rare MLH1 (frequency <5%) haplotype, increasing the risk of colorectal cancer: (OR = 9.76; 95% CI, 1.25 to 76.29; p = 0.03). The two-locus interaction analysis has exhibited signs of interaction between SNPs located in genes MSH6 and MSH2. Global testing has showed no evidence of interaction. CONCLUSION: It is unlikely that common variants in MMR genes contribute significantly to colorectal cancer.


Assuntos
Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
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