RESUMO
Compared to the canonical sphingoid backbone of sphingolipids (SLs), atypical long-chain bases (LCBs) lack C1-OH (1-deoxy-LCBs) or C1-CH2OH (1-deoxymethyl-LCBs). In addition, when unsaturated, they present a cis-double bond instead of the canonical Δ4-5 trans-double bond. These atypical LCBs are directly correlated with the development and progression of hereditary sensory and autonomic neuropathy type 1 and diabetes type II through yet unknown mechanisms. Changes in membrane properties have been linked to the biological actions of SLs. However, little is known about the influence of the LCB structure, particularly 1-deoxy(methyl)-LCB, on lipid-lipid interactions and their effect on membrane properties. To address this question, we used complementary fluorescence-based methodologies to study membrane model systems containing POPC and the different LCBs of interest. Our results show that 1-deoxymethyl-LCBs have the highest ability to reduce the fluidity of the membrane, while the intermolecular interactions of 1-deoxy-LCBs were found to be weaker, leading to the formation of less-ordered domains compared to their canonical counterparts-sphinganine and sphingosine. Furthermore, while the presence of a trans-double bond at the Δ4-5 position of the LCB increased the fluidity of the membrane compared to a saturated LCB, a cis-double bond completely disrupted the ability of the LCB to segregate into ordered domains. In conclusion, even small changes on the structure of the LCB, as seen in 1-deoxy(methyl)-LCBs, strongly affects lipid-lipid interactions and membrane fluidity. These results provide evidence that altered balance between species with different LCBs affect membrane properties and may contribute to the pathobiological role of these lipids.
RESUMO
The availability of first-line medicines for the treatment of drug-susceptible tuberculosis (TB) is inconsistent across European countries. This is particularly worrisome for child-friendly medicines. There are reported examples of physicians being forced to adapt and/or combine formulations intended for adults to treat children with TB. Reduced compliance, unknown effects on treatment outcomes and unpredictable toxicity are potential consequences of resorting to these suboptimal treatment options. Furthermore, the use of these alternatives may increase the risk of drug-resistant TB. This study analysed the availability and use of TB medicines in the European Union (EU)/European Economic Area, with a particular focus on child-friendly formulations. We sought to carry out a full review of the situation by means of a survey involving the EU regulatory network. Countries were asked to confirm marketing status of anti-drug-susceptible-TB medicines, ways used to overcome their absence in their territory and the general difficulties they face to treat children with TB. Results confirmed that rifampicin suspension is the only child-friendly formulation available in Europe, approved in just 10 member states. Overall, 24 countries out of 30 considered the lack of adequate drug-susceptible TB medicines an unmet medical need. To overcome this, countries confirmed that they resort to importation or use adapted formulations. The joint forces of European institutions and pharmaceutical industry are crucial for the development of paediatric formulations and contribute to better compliance and health outcomes.
RESUMO
INTRODUCTION: Confinement measures that were imposed during the COVID-19 pandemic drastically changed the routines of the population. Some studies on the impact of confinement on glycemic control suggest a reduction of 0.1 to 0.5% in glycated hemoglobin. The objective of this study was to evaluate the impact of the COVID-19 pandemic lockdown on glycemic control in adult patients with type 1 diabetes mellitus. METHODS: An observational retrospective cohort study of patients with type 1 diabetes mellitus followed in a Diabetes Unit was performed. The study compared the metabolic control of these patients before (between January 1st and March 18th, 2020) and after (between May 3rd and July 31st, 2020) the lockdown. RESULTS: The study included 102 patients with type 1 diabetes mellitus (51% females), with a median age of 36 years (interquartile range 18.75, (24.25-43)) and a median duration of diabetes of 15 years (interquartile range 13, (8-21)). After lockdown, a significant decrease of 0.28±0.71% in glycated hemoglobin was observed (7.88±1.33% vs 7.59±1.23%, p=<0.001). In patients using continuous glucose monitoring a significant improvement in time in range was also noted (47.25±17.33% vs 49.97±18.61%, p=0.008). CONCLUSIONS: This study demonstrated an improvement in glycemic control after the lockdown. This might be explained by the positive impact of stable schedules, healthy meals and greater availability to make therapeutic adjustments to glycemic control. The fact that diabetes was considered a risk factor for the development of severe COVID-19 disease might also influence patients to increase their efforts to optimize their glycemic control.
RESUMO
Type 1 diabetes mellitus (T1DM) and multiple sclerosis (MS) have been described as chronic organ-specific diseases, approached by different medical specialties. However, they share more etiologic and pathologic features than expected between two autoimmune diseases. The authors present the case of a 40-year-old Caucasian male, diagnosed with type 1 diabetes mellitus at age 18, with poor metabolic control in the early years after the diagnosis. Fourteen years after the diagnosis of diabetes, he started complaining of paresthesias in both feet and sexual dysfunction. Months later, he began to have episodes of muscle weakness and decreased strength in the right lower limb, with a relapsing-remitting pattern and diplopia. This typical course of the symptoms associated with characteristic findings in brain magnetic resonance imaging, with multiple lesions, with evidence of space and time dissemination, established the diagnosis of multiple sclerosis. The presence of oligoclonal bands in the cerebrospinal fluid analysis sustained this diagnosis. Other alternative etiologies were excluded. People with type 1 diabetes mellitus are at an increased risk for other autoimmune diseases, with autoimmune thyroiditis (AIT), celiac disease, and pernicious anemia being the most common. Other less recognized associations, such as the co-occurrence of type 1 diabetes mellitus and multiple sclerosis, are also more frequent than might be thought, with studies reporting a threefold to fivefold higher prevalence of T1D in patients with MS. The exact mechanism behind this co-occurrence is not fully understood, but environmental factors (viral infections and vitamin D deficiency) and variations in non-human leucocyte antigen (HLA) class II alleles may be implicated. Understanding the similarities in the etiology and pathophysiology of these diseases may help clarify causality and create new strategies for the management of these conditions.
RESUMO
INTRODUCTION: The regulatory approval of medical products in countries with limited regulatory resources can be lengthy, which often compromises patients' timely access to much-needed medicines. To improve the efficiency of regulatory systems, reliance is being used. Reliance allows an authority to leverage the work performed by other authorities, such as scientific evaluations, to decide on medical products approval within their jurisdiction. This reduces duplication of regulatory efforts, resources and time, while maintaining national sovereignty. AREAS COVERED: This article analyzes the outcomes and stakeholders' experience of using medicines assessments performed by Stringent Regulatory Authorities (SRA) in the Collaborative Registration Procedures (CRP). Since its establishment in 2015, 59 approvals were granted to 16 medicines in 23 countries through SRA CRP. Results show that the procedure is delivering on the intended benefits of access and speed, with long-term positive impact for resource-limited countries. The article concludes with recommendations on the need for guidance on management of post-approval changes, wider promotion of the procedure, and increased collaboration between authorities. EXPERT OPINION: The SRA CRP provides a mechanism for the use of reliance by strengthening communication and promoting the exchange of information among regulators. This fosters faster regulatory approvals and, consequently, earlier access to medicines.
Assuntos
Organização Mundial da Saúde , HumanosRESUMO
Aortic valve stenosis can be complicated by gastrointestinal bleeding from angiodysplasia. A deficiency of high molecular weight multimers of von Willebrand factor (vWF) (type 2A von Willebrand disease) provides the link between this association, which is known as Heyde syndrome. Aortic valve replacement corrects the vWF abnormalities with long-term resolution of gastrointestinal bleeding. The authors present a case report and a review of this association.
Assuntos
Angiodisplasia/complicações , Estenose da Valva Aórtica/complicações , Hemorragia Gastrointestinal/etiologia , Idoso , Humanos , Masculino , SíndromeRESUMO
Sickle cell disease is an inherited chronic haemolytic anaemia whose clinical manifestations arise from the tendency of the haemoglobin to polymerize and deform red blood cells into the characteristic sickle shape (HbS), with vaso-occlusive phenomena, pain and organ damage. Sickle cell anaemia, the prototype disease, is the homozygous state and represents the most severe form of sickle cell disease. A variety of other sickle cell syndromes are a result of an interaction between HbS and certain variant haemoglobins as HbC and thalassemia. We describe the case of a 28-year-old, black man, with recurrent episodes of musculoskeletal pain. Physical examination revealed spenomegaly. Laboratory tests showed haemolytic anemia and microcytosis. The peripheral blood smear revealed frequent target cells. The high performance liquid chromatography (HPLC) detected the absence of HbA, increased HbA2 and the presence of HbS and HbC, in equal amounts. In this case, we want to draw attention to less common and non-rheumatic causes of musculoskeletal pain as well as alert to the importance of early diagnosis of sickle cell disease that can minimize and prevent many of its complications.
Assuntos
Anemia Falciforme/complicações , Dor Musculoesquelética/etiologia , Talassemia alfa/complicações , Adulto , Humanos , MasculinoRESUMO
Temporal arteritis is a chronic vasculitis of medium and large-size vessels and involves particularly extracranial branches of the aortic arch arteries. Authors report the case of a 73-year-old woman who presented to the hospital after looking for medical counselling three times because of unexplained fever, fatigue, nonproductive cough, and throat pain. She already completed two antibiotic prescriptions. This 3-week history completed in the last days with temporal bilateral headache and visual disturbance. Physical examination was notable for fever and bilateral thickened tender temporal arteries. The erythrocyte sedimentation rate was elevated. A biopsy specimen of the left temporal artery confirmed the diagnosis of giant cell temporal arteritis. The diagnostic suspicion of this disease is clinical and usually simple, but in 10% there are throat pain, non-productive cough and fever which are misunderstood as superior respiratory tract infections leading to diagnosis and treatment delay.