Dysphagia as a Main Symptom of Myasthenia Gravis in a Middleaged Adult Male: A Case Report

Background: Myasthenia gravis (MG) is a rare neuromuscular disorder resulting from the destruction of acetylcholine receptors at the neuromuscular junction by IgG antibodies. Although dysphagia is a common symptom in generalized form of MG, it is rarely reported as a sole manifestation of the disease, specifically in younger patients. Herein, we report a middle-aged adult patient with dysphagia as the sole manifestation of MG.Case presentation: A 49-year-old male complaining of severe dysphagia underwent an extensive clinical and paraclinical examination. Oropharyngeal dysphagia was confirmed by an experienced speech-language pathologist using the water swallowing test. Unilateral right paresis of the soft palate and vocal fold was confirmed using laryngeal video stroboscopy. Chest computerized tomography (CT) scan, brain Magnetic resonance imaging (MRI), and routine blood, urine, and thyroid tests were normal. In electromyography, slow repetitive nerve stimulation (RNS) showed a decremental response in the right nasalis muscle. The diagnostic neostigmine test with 1.5 mg of intramuscular neostigmine led to significant recovery of laryngeal and pharyngeal motor dysfunction and dysphagia within 12 hours, so the MG diagnosis was confirmed. The patient was treated with plasmapheresis, pyridostigmine, and prednisolone, which followed an improving course and led to better swallowing of solid and liquid foods.Conclusion: MG should be considered as a diagnosis in middle-aged adults with complaints of dysphagia

A new delivery model to increase adherence to methadone maintenance treatment

Dear Editor, Today, a large number of Iranian addicts are treated in methadone maintenance treatment (MMT) centers (1). According to the current procedure, each patient has treatment record in only one clinic. So, each patient is able to get prescribed medications and other medical services of the center. Receiving drugs and center-based services has always faced serious challenges such as access (2). For example, some patients with mobility jobs, people with movement restrictions and physical conditions, and patients living in rural and remote areas are unable to refer to get the medication according to a regular timetable (3). The mentioned issues are a serious challenge for persistence and adherence to MMT. Under such circumstances, a significant proportion of patients abandoned treatment plan and they lost the ancillary services, including medical visits, psychological interventions, and physical and emotional support from a social worker. Ultimately, this situation led to an increased the risk of relapse and resume high risk behaviors related to substance abuse (4). Social damage and financial losses of the country's health system are only some of the negative consequences of this situation. Based on these considerations, presentation of the strategies and constructive recommendations in support of the related organizations is a necessity. Despite the several offers raised, it seems that the abolition of the system receiving drugs from the origin center and the use of digital identification systems can be useful and practical (5). In the form of drug delivery system, patients can receive their daily dosages in any of the center across the country. This project is done in such a manner that each patient first enrolls in an MMT center and fills out a medical record form. Then, the doctor will determine the types of medication and drug dose based on the patients’ medication history. In the first three months of treatment (i.e. until the stabilization of the dose), visits or appointments will be face to face. After the period and stabilized drug dose, the patient who receives medication is no longer confined to the origin center. This means that each patient is issued an entity identifier such as a smart card for medication. By issuing the smart card, the patient can receive quota set medication use in any part of the country. Definitely to prevent abuse of patients, it is recommended that the patient's identity be verified through the finger, eye, or facial recognition digital sensors (5). Meanwhile, bringing up an instruction can be useful based on a mandatory visit to the center of origin for medical examination and psychological services at least once a month. So far, few studies have been conducted to review and confirm the delivery format of pharmaceutical services (6, 7). However, previous studies show that the facial assessment via computer evaluation and photo anthropometric variations in facial features are standard references for personal identification in the field of health and forensic (8, 9). Thus, our offer could possibly be effective in increasing adherence to treatment and reducing problems caused by the access to origin MMT center. As a result, we recommend using this pilot model for at least a one-year period. Then, if the benefit of this model is in practice, this proposal could be implemented permanently

Overview on Multienzymatic Cascades for the Production of Non-canonical α-Amino Acids

SM-R thanks the University of Granada for the support provided by project PPJI2017-1 and the European Cooperation in Science and Technology (COST Action CA15133). Authors are also grateful to the Andalusian Regional Government through Endocrinology & Metabolism Group (CTS-202).The 22 genetically encoded amino acids (AAs) present in proteins (the 20 standard AAs together with selenocysteine and pyrrolysine), are commonly referred as proteinogenic AAs in the literature due to their appearance in ribosome-synthetized polypeptides. Beyond the borders of this key set of compounds, the rest of AAs are generally named imprecisely as non-proteinogenic AAs, even when they can also appear in polypeptide chains as a result of post-transductional machinery. Besides their importance as metabolites in life, many of D-α- and L-α-“non-canonical” amino acids (NcAAs) are of interest in the biotechnological and biomedical fields. They have found numerous applications in the discovery of new medicines and antibiotics, drug synthesis, cosmetic, and nutritional compounds, or in the improvement of protein and peptide pharmaceuticals. In addition to the numerous studies dealing with the asymmetric synthesis of NcAAs, many different enzymatic pathways have been reported in the literature allowing for the biosynthesis of NcAAs. Due to the huge heterogeneity of this group of molecules, this review is devoted to provide an overview on different established multienzymatic cascades for the production of non-canonical D-α- and L-α-AAs, supplying neophyte and experienced professionals in this field with different illustrative examples in the literature. Whereas the discovery of new or newly designed enzymes is of great interest, dusting off previous enzymatic methodologies by a “back and to the future” strategy might accelerate the implementation of new or improved multienzymatic cascades.University of Granada PPJI2017-1European Cooperation in Science and Technology (COST) CA15133Andalusian Regional Government through Endocrinology & Metabolism Group CTS-20

CYP105-diverse structures, functions and roles in an intriguing family of enzymes in 'Streptomyces'

The cytochromes P450 (CYP or P450) are a large superfamily of haem-containing enzymes found in all domains of life. They catalyse a variety of complex reactions, predominantly mixed-function oxidations, often displaying highly regio- and/or stereospecific chemistry. In streptomycetes, they are predominantly associated with secondary metabolite biosynthetic pathways or with xenobiotic catabolism. Homologues of one family, CYP105, have been found in all Streptomyces species thus far sequenced. This review looks at the diverse biological functions of CYP105s and the biosynthetic/catabolic pathways they are associated with. Examples are presented showing a range of biotransformative abilities and different contexts. As biocatalysts capable of some remarkable chemistry, CYP105s have great biotechnological potential and merit detailed study. Recent developments in biotechnological applications which utilize CYP105s are described, alongside a brief overview of the benefits and drawbacks of using P450s in commercial applications. The role of CYP105s in vivo is in many cases undefined and provides a rich source for further investigation into the functions these enzymes fulfil and the metabolic pathways they participate in, in the natural environment