Alopecia areata (AA) is an autoimmune disease that presents as nonscarring hair loss, although the exact pathogenesis of the disease remains to be clarified. Disease prevalence rates from 0.1% to 0.2% have been estimated for the United States. AA can affect any hair-bearing area. It often presents as well demarcated patches of nonscarring alopecia on skin of overtly normal appearance. Recently, newer clinical variants have been described. The presence of AA is associated with a higher frequency of other autoimmune diseases. Controversially, there may also be increased psychiatric morbidity in patients with AA. Although some AA features are known poor prognostic signs, the course of the disease is unpredictable and the response to treatment can be variable. Part one of this two-part series on AA describes the clinical presentation and the associated histopathologic picture. It also proposes a hypothesis for AA development based on the most recent knowledge of disease pathogenesis. Learning objectives After completing this learning activity, participants should be familiar with the most recent advances in AA pathogenesis, recognize the rare and recently described variants of AA, and be able to distinguish between different histopathologic stages of AA.

https://www.saudedireta.com.br/docsupload/1332243235a%20areata.pdf

Alopecia areata update: Part I. Clinical picture, histopathology, and pathogenesis

In the last 15 years, the genus Malassezia has been a topic of intense basic research on taxonomy, physiology, biochemistry, ecology, immunology, and metabolomics. Currently, the genus encompasses 14 species. The 1996 revision of the genus resulted in seven accepted taxa: M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. restricta, and M. slooffiae. In the last decade, seven new taxa isolated from healthy and lesional human and animal skin have been accepted: M. dermatis, M. japonica, M. yamatoensis, M. nana, M. caprae, M. equina, and M. cuniculi. However, forthcoming multidisciplinary research is expected to show the etiopathological relationships between these new species and skin diseases. Hitherto, basic and clinical research has established etiological links between Malassezia yeasts, pityriasis versicolor, and sepsis of neonates and immunocompromised individuals. Their role in aggravating seborrheic dermatitis, dandruff, folliculitis, and onychomycosis, though often supported by histopathological evidence and favorable antifungal therapeutic outcomes, remains under investigation. A close association between skin and Malassezia IgE binding allergens in atopic eczema has been shown, while laboratory data support a role in psoriasis exacerbations. Finally, metabolomic research resulted in the proposal of a hypothesis on the contribution of Malassezia-synthesized aryl hydrocarbon receptor (AhR) ligands to basal cell carcinoma through UV radiation-induced carcinogenesis.

The Malassezia Genus in Skin and Systemic Diseases

A gene mutated in Charcot-Marie-Tooth disease type 4B (CMT4B), an autosomal recessive demyelinating neuropathy with myelin outfoldings, has been mapped on chromosome 11q22. Using a positional-cloning strategy, we identified in unrelated CMT4B patients mutations occurring in the gene MTMR2, encoding myotubularin-related protein-2, a dual specificity phosphatase (DSP).

Charcot-Marie-Tooth type 4B is caused by mutations in the gene encoding myotubularin-related protein-2

Background
A Task Force was convened by the EFNS/MDS-ES Scientist Panel on Parkinson's disease (PD) and other movement disorders to systemically review relevant publications on the diagnosis of PD.

Methods
Following the EFNS instruction for the preparation of neurological diagnostic guidelines, recommendation levels have been generated for diagnostic criteria and investigations.

Results
For the clinical diagnosis, we recommend the use of the Queen Square Brain Bank criteria (Level B). Genetic testing for specific mutations is recommended on an individual basis (Level B), taking into account specific features (i.e. family history and age of onset). We recommend olfactory testing to differentiate PD from other parkinsonian disorders including recessive forms (Level A). Screening for pre-motor PD with olfactory testing requires additional tests due to limited specificity. Drug challenge tests are not recommended for the diagnosis in de novo parkinsonian patients. There is an insufficient evidence to support their role in the differential diagnosis between PD and other parkinsonian syndromes. We recommend an assessment of cognition and a screening for REM sleep behaviour disorder, psychotic manifestations and severe depression in the initial evaluation of suspected PD cases (Level A). Transcranial sonography is recommended for the differentiation of PD from atypical and secondary parkinsonian disorders (Level A), for the early diagnosis of PD and in the detection of subjects at risk for PD (Level A), although the technique is so far not universally used and requires some expertise. Because specificity of TCS for the development of PD is limited, TCS should be used in conjunction with other screening tests. Conventional magnetic resonance imaging and diffusion-weighted imaging at 1.5 T are recommended as neuroimaging tools that can support a diagnosis of multiple system atrophy (MSA) or progressive supranuclear palsy versus PD on the basis of regional atrophy and signal change as well as diffusivity patterns (Level A). DaTscan SPECT is registered in Europe and the United States for the differential diagnosis between degenerative parkinsonisms and essential tremor (Level A). More specifically, DaTscan is indicated in the presence of significant diagnostic uncertainty such as parkinsonism associated with neuroleptic exposure and atypical tremor manifestations such as isolated unilateral postural tremor. Studies of [123I]MIBG/SPECT cardiac uptake may be used to identify patients with PD versus controls and MSA patients (Level A). All other SPECT imaging studies do not fulfil registration standards and cannot be recommended for routine clinical use. At the moment, no conclusion can be drawn as to diagnostic efficacy of autonomic function tests, neurophysiological tests and positron emission tomography imaging in PD.

Conclusions
The diagnosis of PD is still largely based on the correct identification of its clinical features. Selected investigations (genetic, olfactory, and neuroimaging studies) have an ancillary role in confirming the diagnosis, and some of them could be possibly used in the near future to identify subjects in a pre-symptomatic phase of the disease.

https://onlinelibrary.wiley.com/doi/epdf/10.1111/ene.12022

EFNS/MDS‐ES recommendations for the diagnosis of Parkinson's disease

Voltage-gated Na + (Na v ) channels are highly concentrated at nodes of Ranvier in myelinated axons and facilitate rapid action potential conduction. Autoantibodies to gangliosides such as GM1 have been proposed to disrupt nodal Nav channels and lead to Guillain-Barre syndrome, an autoimmune neuropathy characterized by acute limb weakness. To test this hypothesis, we examined the molecular organization of nodes in a disease model caused by immunization with gangliosides. At the acute phase with progressing limb weakness, Na v channel clusters were disrupted or disappeared at abnormally lengthened nodes concomitant with deposition of IgG and complement products. Paranodal axoglial junctions, the nodal cytoskeleton, and Schwann cell microvilli, all of which stabilize Na v channel clusters, were also disrupted. The nodal molecules disappeared in lesions with complement deposition but no localization of macrophages. During recovery, complement deposition at nodes decreased, and Na v channels redistributed on both sides of affected nodes. These results suggest that Na v channel alterations occur as a consequence of complement-mediated disruption of interactions between axons and Schwann cells. Our findings support the idea that acute motor axonal neuropathy is a disease that specifically disrupts the nodes of Ranvier.

https://www.jneurosci.org/content/jneuro/27/15/3956.full.pdf

Anti-GM1 antibodies cause complement-mediated disruption of sodium channel clusters in peripheral motor nerve fibers.

Dear Editor, Xanthogranulomatous inflammation is a rare type of chronic inflammatory process which is histologically characterized by a collection of foamy macrophages admixed with inflammatory infiltrate. It was previously reported that a delayed-type hypersensitivity reaction of cell-mediated immunity might be implicated in the pathogenesis of xanthogranulomatous inflammation, which occurs most commonly in the kidney, followed by the gallbladder; the lung, brain and bone are rarely affected. We describe herein a rare case of xanthogranulomatous osteomyelitis (XO) of the distal tibia which caused ankle pain in an otherwise healthy woman. A previously healthy 36-year-old Japanese woman presented with a 2-week history of right ankle pain. She noticed the pain when at rest and did not notice pain when she was in motion. Her ankle was slightly tender, but there was no sign of inflammation, and her ankle motion, including the range of motion, was not restricted. Laboratory findings showed: white blood cell count, 5000 cells/lL (normal values, 2800–8800 cells/ lL); alkaline phosphatase, 104 IU/L (115–359 IU/L); C-reactive protein, < 0.03 mg/dL (0–0.3 mg/dL). The results of other serum biochemical examinations including liver and renal function tests were within the normal ranges. Plain radiographs of the right ankle showed an osteolytic lesion with a focal sclerotic rim and cortical expansion in the diametaphysis of the distal posteromedial tibia (Fig. 1a,b). Magnetic resonance imaging (MRI) revealed an intraosseous lesion measuring 4.2 9 2.3 9 1.9 cm in size displaying high intensity on T1-weighted imaging (WI) (Fig. 1c), with mixed high and very high intensity with peripheral low intensity on T2-WI (Fig. 1d), and heterogeneous intraosseous enhancement with periosteal diffuse enhancement on gadolinium-enhanced T1-weighted fat-suppression imaging (Fig. 1e). Wholebody bone scintigraphy showed increased uptake in the right distal tibia (Fig. 1f). Since the lesion was initially suspected to be a primary bone tumor, an incisional biopsy was performed. Although a critical pathological diagnosis was not obtained and the bacterial culture was negative, the lesion was judged to be compatible with an inflammation process. In order to rule out malignancy, we performed an excisional biopsy and completely curetted out the lesion. Grossly, the specimen was yellowishgray (Fig. 2a), and the re-examined bacterial culture was negative. Since the histopathological examination showed a collection of foamy cells and histiocytes, and a fibrous granuloma with a wide necrosis site (Fig. 2b, c), we made the diagnosis of XO. The patient has postoperatively shown no symptoms or signs of local recurrence for 29 months. XO is an extremely rare inflammatory disease, and to the best of our knowledge, only 11 cases of XO, including the present case, have been reported in the English literature. A review of these 11 cases, including the present case, found that XO occurs predominantly in males (9/11 cases) with no characteristic age distribution. Although the relationship between race and XO is still obscure, eight of the 11 reported cases of XO were from Asian countries. Nine cases were unicentric (four cases in the tibia, the present case, three cases in the rib and two cases in the ulna) and two cases were multicentric (one in the humerus and fibula and the other in the medial malleoli, talus and cuboid bone), indicating that long tubular bones are the most commonly affected sites of XO. Additionally, when a diagnosis of XO is established, radiological analyses of the whole body are needed to look for other lesions, given the possibility of multicentric cases. In six out of 10 prior cases, nonspecific abnormal laboratory data, including leukocytosis and elevations of the erythrocyte sedimentation rate and alkaline phosphatase level were observed, whereas no abnormal laboratory findings were observed in the other

Xanthogranulomatous osteomyelitis of the distal tibia: a case report

Very late relapse of high-grade osteosarcoma: A case report and review of the literature.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Osamu Hasegawa

Author Tools

Chat about Author

Papers

Xanthogranulomatous osteomyelitis of the distal tibia: a case report

Very late relapse of high-grade osteosarcoma: A case report and review of the literature.