Oval Plaques Research Articles

Neuromuscular Junction Development Differs Between Extraocular and Skeletal Muscles and Between Different Extraocular Muscles.

To determine whether development of neuromuscular junctions (NMJs) differs between extraocular muscles (EOMs) and other skeletal muscles. Mouse EOMs, diaphragm, and tibialis anterior (TA) were collected at postnatal day (P)0, P3, P7, P10, P14, and P21, and 12 weeks. Whole muscles were stained with α-bungarotoxin, anti-neurofilament antibody, and slow or fast myosin heavy chain antibody, and imaged with a confocal microscope. Images were quantified using Imaris software. NMJs in the EOMs show a unique pattern of morphological development compared to diaphragm and TA. At P0, diaphragm and TA NMJs were oval plaques; EOM single NMJs were long, thin rods. NMJs in the three muscle types progress to mature morphology at different rates. At all ages, EOM single NMJs were larger, especially relative to myofiber size. The inferior oblique and inferior rectus muscles show delayed single NMJ development compared to other EOMs. NMJs on multiply-innervated fibers in the EOMs vary widely in size, and there were no consistent differences between muscles or over time. Incoming motor nerves formed complex branching patterns, dividing first into superficial and deep branches, each of which branched extensively over the full width of the muscle. Motor axons that innervate multiply-innervated fibers entered the muscle with the axons that innervate singly-innervated fibers, then extended both proximally and distally. EOM NMJs had more subsynaptic nuclei than skeletal muscle NMJs throughout development. EOMs show a unique pattern of NMJ development and have more subsynaptic nuclei than other muscles, which may contribute to the exquisite control of eye movements.

Dermoscopic Findings of Clonal Seborrheic Keratosis and Pigmented Basal Cell Carcinoma in the Skin of Color Patients - A Comparison.

Dermoscopic Findings of Clonal Seborrheic Keratosis and Pigmented Basal Cell Carcinoma in the Skin of Color Patients - A Comparison.

An asymmetric morbilliform eruption in an adult male

An asymmetric morbilliform eruption in an adult male

Correlation of Contact Sensitization to Common Allergens with Disease Severity in Discoid Eczema

Background: Discoid eczema, defined by well-demarcated round or oval plaques, is a form of endogenous eczema in which the role of contact allergens is not clearly established. Objectives: This study aims to assess the role of contact allergens in discoid eczema by patch testing, determine clinical relevance and correlate patch test reactivity with the severity of disease and atopy. Materials and Methods: Sample characteristics including occupation, atopic diathesis and clinical details were recorded. Disease severity was assessed by the Eczema and Area Severity Index (EASI) and patch testing carried out with the Indian Standard Battery. Relevance of patch tests was determined by a history of exposure and patch testing with patients' own materials. Results: Fifty-one patients having a median age of 38 years were enrolled out of which 31 (60.8%) were male. Patch tests were reactive in 25 (49%) patients, common sensitizers being fragrance mix in 9 (31.0%), potassium dichromate in 4 (13.8%), paraphenylenediamine in 4 (13.8%), and nickel in 3 (10.3%) cases. Clinical relevance was established in 11 (37.9%) cases. In patch test reactive patients the mean EASI score was 3.4 as compared with 4.5 in nonreactors. Patch tests were positive in 3 (25%) atopic as compared with 22 (56.4%) nonatopic patients. Conclusion: Contact sensitization to common allergens may not contribute to disease severity in discoid eczema. Patch test reactivity is low in atopic as compared with nonatopic patients with discoid eczema.

Vesicular Erythema Migrans with Subsequent Jarisch-Herxheimer Reaction Mimicking Cellulitis.

A 47-year-old man with no significant medical history presented with a 5-day history of an expanding plaque on his left thigh. The patient had fevers up to 38.1°C, chills, malaise, and joint stiffness. He noted recent time spent in the woods but denied known tick bites. On examination, the left thigh had a nontender, oval plaque with central vesicles on a red base and a surrounding rim of pink erythema (Figure 1). Based on the patient's clinical history and examination, a diagnosis of vesicular erythema migrans (EM) was made and doxycycline was initiated.

Lako rešivo kada se prepozna - prikaz slučaja - kutana larva migransa

Introduction: Cutaneous larva migrans (CLM) is a syndrome, defined by clinical appearance of slowly migrating cutaneous eruption caused by inoculation with animal hookworms larvae in the skin. Despite the typical clinical presentation, CLM is frequently misdiagnosed due to its rarity in temperate climate urban communities. Case Report: We report a case of a 42-year old female, admitted to an outpatient clinic with eruption of multiple intense pruritic, erythematous, exudative papules and oval plaques, located predominately on the back. The patient claimed that skin lesions started three weeks before the examination, during her vacation in Thailand, and at first, was taught to be caused by a contact with jelly fish. Lesions were treated unsuccessfully with oral antihistamines and various topical corticosteroids, which lead to more questions regarding the differential diagnosis. Dermoscopical and histopathological findings were indicative of parasitic infection, most likely CLM. A three-day course of oral albendazole, 400 mg daily, resulted in complete cure of the disease. Conclusions: Careful clinical examination and detailed history taken from the patient are fundamentals for creating a set of differential diagnoses, that can be further clarified by the use of laboratory findings, imaging methods (including dermoscopy) and biopsy with histopathology. Although CLM has a benign self-limiting course, intense itch may substantially impact the quality of life, and possible visceral involvement or concomitant parasitic infection may lead to serious health deterioration in unrecognized cases.

Acne Keloidalis Nuchae – Case Report

Abstract Acne keloidalis nuchae (AKN) / folliculitis keloidalis nuchae (FKN) is a chronic inflammatory condition which involves hair follicles localized predominantly in occipital scalp and posterior neck area leading to hypertrophic scarring alopecia. We present a 59-year-old factory worker, Caucasian male with a whitish alopecic oval plaque about 10 cm in diameter in the occipital region. The peripheral part of plaque was mildly inflammated, with groups of tufted terminal hairs, while the central part showed cicatricial alopecia and discrete non-adherent dry scales. Skin changes firstly occurred 6 years earlier, as itchy papules and pustules that sometimes healed with scarring. The applied relevant diagnostic and therapeutical measures are discussed in this report.

Fixed Drug Eruption to Biologics and Role of Lesional Patch Testing

A 40-year-old cashier with ankylosing spondylitis (AS) on anti–TNF-α therapy presented to the Immunology Clinic with an intermittent rash over her shin. She had been on regular subcutaneous adalimumab (AbbVie, North Chicago, IL) for the past 5 years and her AS was in remission. For the past 3 months, there was consistent recurrence of a solitary rash over her left anterior shin around 4 hours after every dose of adalimumab. Adalimumab was administered every 2 weeks to alternating thighs without history of local injection-site reactions. The lesions were well demarcated, beginning with an intense itch and burning sensation followed by a fixed erythematous oval plaque about 10 cm in diameter. The lesion would last for days with residual hyperpigmentation (Figure 1, A) and recurred after each dose. There was no interruption of her injections and no recent change in the “citrate-free” autoinjector formulation (confirmed with supplier). There were no new medications and she had no history of dermatological conditions. There was no history of trauma. The lesions got progressively worse with subsequent injections, and there was a localized vesicular eruption on her most recent episode (Figure 1, B). She declined a skin biopsy. Adalimumab was stopped and there was no recurrence of the rash. A fixed drug eruption (FDE) was suspected and drug patch testing was performed 2 months later after complete healing of the rash. Patch testing was performed using IQ Ultra chambers and adalimumab (directly extracted from the autoinjector and diluted 1:10 aqueous) with both control (uninvolved upper back skin) and lesional (residual pigmented lesion) patch test application. The patch tests were read on day 2 (D2) and day 4 (D4), in accordance with International Contact Dermatitis Research Group criteria. Patch testing result was negative at the control site at D2 and D4. Patch testing result was negative at the lesional site at D2 (Figure 2, A), but strongly positive (++) at D4 (Figure 2, B) with reactivation of the residual FDE lesion with a crescendo effect. Given the positive lesional patch test result and the suggestive clinical features, she was diagnosed with an FDE due to adalimumab. In view of her favorable response to TNF-α blockade, she consented to provocation testing with subcutaneous golimumab (another anti–TNF-α antagonist), which was well tolerated. Her AS continues to be in remission with golimumab. We previously reported on immediate-type hypersensitivity to adalimumab, and hypersensitivity reactions to biologics have been increasingly identified.1Li P.H. Watts T.J. Lui M.S. Lau C.S. Chung H.Y. Recall urticaria in adalimumab hypersensitivity.J Allergy Clin Immunol Pract. 2018; 6: 1032-1033Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar, 2Corominas M. Gastaminza G. Lobera T. Hypersensitivity reactions to biological drugs.J Investig Allergol Clin Immunol. 2014; 24: 212-225PubMed Google Scholar In this case, we report the first case of biologics-related FDE. An FDE is a delayed-type cutaneous hypersensitivity reaction to medication that recurs at the same site on further exposure and cross-reactivity is uncertain. In this case, tolerance to golimumab was demonstrated, suggesting a lack of cross-reactivity with an alternative anti–TNF-α antagonist. Adalimumab and golimumab are humanized IgG1 anti–TNF-α antibodies but likely structurally dissimilar, because both are complex macromolecules derived from different biological cell lines. We highlight the utility of lesional patch testing in biologics-related FDE and suggest that tolerance to other anti–TNF-α antagonists is possible, but more studies are required to determine the true rate of cross-reactivity.

Basal Cell Carcinoma: An Unusual Localization and a Typical Dermoscopy

Clinical Image Basal cell carcinoma is a frequent disease that can be caused by chronic exposition to UV radiation. Dermoscopy is a very helpful device that can lead to diagnosis. Mr. M.G is 63-years-old man that presents a rough pigmented plaque on the back since more than 5 years. Recently it becomes slightly itchy. Clinically: A 3 cm pigmented oval plaque on the back. On dermoscopy screening maple leaf-like area, spoke wheel areas, blue-gray nests, gray-blue globules, pink white area, digitiform structures seen. We removed the lesion with 5 mm of margin. The histopathology concluded to a nodular basal cell carcinoma with healthy margin. The patient was advised to apply photo protection measures and a follow-up once a year. Keywords: Pigmented basal cell carcinoma; Diagnosis; Dermoscopy

Clinical Features and Visual outcome in Acute and Recurrent Case of Optic Neuritis.

Introduction: Optic neuritis is an inflammation of the optic nerve that usually affects young females. In Western countries, natural history and treatment of optic neuritis(ON) has been studied extensively. However aetiology, natural history, clinical features of ON and their relation to multiple sclerosis in Asian population needs to be defined yet.
 Methods: 30 patients who were diagnosed as optic neuritis were included between June 2013 to December 2014 at BP Koirala Lions Centre for Ophthalmic Studies (BPKLCOS). A detailed history was obtained followed by examination of anterior and posterior segment. Assessment of visual acuity, color vision, contrast sensitivity, visual evoked potential (VEP),visual field and MRI of orbit and brain was done in all cases. All patients were treated with intravenous Methylprednisolone 500mg twice daily for 3 days followed by oral steroid for 11 days which was tapered in the next 4 days.The patients were reassessed at 2 weeks, 1 month and 3months.
 Results: Commonest presenting symptom was diminution of vision(65%). MRI showed multiple paraventricular oval plaques definite of multiple sclerosis in one patient and one was diagnosed as probable MS who had a single periventricular plaque. Visual evoked potential (VEP) showed increase in the mean P100 latency at 60’ and reduction in amplitude in eyes affected with optic neuritis compared to normal eyes. At 3 months follow up, 70% had good visual recovery (>6/18). The cause of non-improvement in vision was disc pallor. Optic disc pallor was detected in 37.5% of the eyes during follow up.
 Conclusions: Good visual recovery was observed in most eyes with acute optic neuritis. Multiple sclerosis was seen in 1 patient who had recurrent optic neuritis.

Unilateral eruption on the face

From an Sc Fund Conf Corre of A 48-year-old African American woman presented to our department with a rash on her face. The patient reported a 6-month history of an itchy rash only on the left side of her face, where she used her cell phone. She has a cat at home. She also mentioned that she does not typically wear a watch because it caused a rash many years ago. No prescription treatments were used. The patient denied a history of atopy. The physical examination revealed a well-demarcated, oval, skin-colored thin and lichenified plaque on her left cheek, approximately 2.5 cm in diameter, with white scale (Fig 1).

COEXISTÊNCIA DE MORFEIA, VITÍLIGO E DIABETES AUTOIMUNE LATENTE DO ADULTO

Cerca de 30% dos adultos com morfeia apresentam simultaneamente outras doenças auto-imunes, o que suporta a presença de mecanismos de auto-imunidade na patogénese desta doença fibrosante da pele e tecidos subjacentes.Os autores descrevem o caso de um doente do sexo masculino, 27 anos, que notou o aparecimento na região abdominal, cerca de 1 ano antes da observação, de placa eritematosa, ovalada, endurada, assintomática, com crescimento progressivo. Referiu vitiligo acro-facial desde os 12 anos de idade e antecedentes maternos de vitiligo e tiroidite de Hashimoto. A avaliação histopatológica evidenciou escasso infiltrado inflamatório perivascular e espessamento das fibras de colagénio, suportando o diagnóstico clínico de morfeia. Na avaliação laboratorial destacou-se a marcada elevação no título do auto-anticorpo anti-descarboxilase do ácido glutâmico, permitindo o diagnóstico de diabetes auto-imune latente do adulto (LADA), uma forma de diabetes tipo 1 de início tardio.A morfeia e o vitiligo são dermatoses raramente descritas em simultâneo, apesar da sua provável etiologia auto-imune.Neste doente, a investigação de outras doenças auto-imunes permitiu o diagnóstico de LADA. Esta associação, raramente descrita, favorece a hipótese auto-imune.

Clomipramine treatment of acral lick dermatitis in a dog

An 11-year-old, toy poodle dog was presented with dermatologic lesions and mammary gland tumor (MGT) evaluation. A solitary, lobulated MGT (size 2.5 × 3.5 cm) was affecting the 5th left mammary gland. Firm, oval plaque skin lesions were present on the left dorsal carpal area. The skin lesions were alopecic and salivary staining. The dog had historical separation anxiety and excessive licking of skin lesions were observed. Based on the clinical and histopathologic examinations, MGT was diagnosed with mammary complex adenoma and the skin lesions were diagnosed with acral lick dermatitis. Behavior modification treatment using oral clomipramine was effective.

Amotl2 interacts with LL5β, localizes to podosomes and regulates postsynaptic differentiation in muscle

Neuromuscular junctions (NMJs) in mammalian skeletal muscle undergo a postnatal topological transformation from a simple oval plaque to a complex branched structure. We previously showed that podosomes, actin-rich adhesive organelles, promote the remodeling process, and demonstrated a key role for one podosome component, LL5β. To further investigate molecular mechanisms of postsynaptic maturation, we purified LL5β-associated proteins from myotubes and showed that three regulators of the actin cytoskeleton--Amotl2, Asef2 and Flii--interact with LL5β. These and other LL5β-interacting proteins are associated with conventional podosomes in macrophages and podosome-like invadopodia in fibroblasts, strengthening the close relationship between synaptic and non-synaptic podosomes. We then focused on Amotl2, showing that it is associated with synaptic podosomes in cultured myotubes and with NMJs in vivo. Depletion of Amotl2 in myotubes leads to increased size of synaptic podosomes and corresponding alterations in postsynaptic topology. Depletion of Amotl2 from fibroblasts disrupts invadopodia in these cells. These results demonstrate a role for Amotl2 in synaptic maturation and support the involvement of podosomes in this process.

The Henry Davis Gift: A Collection of Bookbindings, vol. iii: A Catalogue of South European Bindings. By MIRJAM FOOT.

Finis coronat opus. The first two volumes of this catalogue appeared in 1978 and 1983. Mirjam Foot has now completed the work in fine style. Her eye is as sharp as ever in recognizing tools and her mastery of the very extensive literature is highly impressive. Each binding is described, and this time the description includes a fuller account of the structure. ‘Provenance’ follows, then ‘References’ to earlier mentions of the binding in print, ‘Literature’ including more general accounts, ‘Same tool on’ — self-explanatory and most helpful, ‘Compare’ — similar bindings but not necessarily by the same shop or even, in the Italian part, from the same town, and, rather infrequently, a ‘Note’. Every binding is illustrated. Gilt bindings are well reproduced, though unfortunately and no doubt inevitably reduced in size, making the identification of tools hazardous. The reproduction of bindings decorated in blind varies from poor to invisible. The oval plaque of the Presentation of Christ in the Temple on nos. 110 and 111, a printed Psalter and Book of Hours respectively of 1582 and 1584, tends towards the lower end of the bracket. Once again, as in the second volume, the British Library photographer has failed to reproduce the spines. This is a serious lacuna as it is often by the treatment of a spine that a binder's work can be recognized. He might experiment with freedom and variety on the covers while remaining conservative on the spines.

Giant melanoacanthoma mimicking malignant melanoma

Melanoacanthoma denotes a rare variant of pigmented seborrheic keratosis. A 65-year-old male farmer had pigmented, verrucous, itchy, highly painful, progressively growing irregularly oval plaque on left side of lower back for the past five years. The indurated lesion, measuring maximum diameter 10 cm × 5 cm, had no discharge, bleeding, ulceration, or associated lymphadenopathy. Dermoscopy showed regular pigmentary network and cribiform pattern of ridges without any feature of malignant melanoma. Histopathology showed well-defined islands of basaloid cells interspersed with large and richly dendritic melanocytes. The lesion was totally excised followed by skin grafting. Our patient was unique in its massive size and clinical resemblance with malignant melanoma. The diagnosis was confirmed by dermoscopy and skin biopsy.

Acute patchy exanthematous pustulosis caused by sulfamethoxazole-trimethoprim

To the Editor: We describe a patient with an acute eruption of asymptomatic, erythematous, edematous, oval plaques studded with pinpoint, nonfollicular pustules on her torso and proximal extremities caused by sulfamethoxazole-trimethoprim (SMZ-TMP). This 40-year-old female had a history of chronic myelogenous leukemia unresponsive to etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, rituximab, and fludarabine (EPOCH-RF) therapy. She subsequently received a matched, related-donor peripheral blood stem cell transplant and donor lymphocyte infusion (DLI of TH2 cells).

Giant annular dermatomyofibroma

A 74‐year‐old lady presented with a painful giant annular abdominal plaque for a duration of 2 years. The plaque developed from a cholecystectomy scar and extended peripherally around it. The patient had had a cholecystectomy for gallstones 10 years previously. She was a diabetic on oral hypoglycaemic agents and had no history of radiotherapy. Physical examination showed a tender well‐demarcated annular erythematous keloid‐like plaque, measuring 13 cm × 15 cm, surrounding a cholecystectomy scar. Another smaller oval plaque, measuring 3 cm × 2 cm, was found on the left side of the abdomen (Fig. 1). The initial clinical diagnosis was dermatofibrosarcoma protuberan (DFSP). A deep incisional biopsy including subcutaneous fat was performed under local anesthesia for pathological examination. Histologically, there was a plaque‐like lesion involving the upper reticular dermis but not extending to the subcutaneous fat. The lesion showed proliferation of spindle‐shaped cells arranged in intersecting fascicles and appeared parallel to the skin surface. Only a vague storiform pattern was seen at the edges. The cells had relatively uniform elongated nuclei and mitosis was not seen. The overlying epidermis showed mild hyperplasia with pigmentation of the basal layer (Fig. 2). Smooth muscle actin was positive (Fig. 3), desmin was negative and CD34 was negative. The final diagnosis was dermatomyofibroma (DMF). Extra‐abdominal fibromatosis was unlikely because broad elongated fascicles among collagenous stroma were not evident, while intersecting fascicles parallel to the skin surface were typical of DMF. The smaller plaque on her left abdomen was excised and gave similar histological and staining results. The giant annular plaque was not excised as the patient refused further surgery. She has since been closely monitored.A well‐demarcated annular erythematous keloid‐like 11 cm × 13 cm plaque surrounding a cholecystectomy scar; a smaller oval plaque measuring 3 cm × 2 cm was found on the left side of the abdomenimageThe lesion shows proliferation of spindle‐shaped cells arranged in intersecting fascicles; most appear parallel to the skin surface. Only a vague storiform pattern is seen (H&E, ×10)imageImmunohistochemical staining with actin shows moderate cytoplasmic staining. Internal positive control is demonstrated by staining of the blood vessel pericytes (SMA, ×5)image

Nerve-independent formation of a topologically complex postsynaptic apparatus.

As the mammalian neuromuscular junction matures, its acetylcholine receptor (AChR)–rich postsynaptic apparatus is transformed from an oval plaque into a pretzel-shaped array of branches that precisely mirrors the branching pattern of the motor nerve terminal. Although the nerve has been believed to direct postsynaptic maturation, we report here that myotubes cultured aneurally on matrix-coated substrates form elaborately branched AChR-rich domains remarkably similar to those seen in vivo. These domains share several characteristics with the mature postsynaptic apparatus, including colocalization of multiple postsynaptic markers, clustering of subjacent myonuclei, and dependence on the muscle-specific kinase and rapsyn for their formation. Time-lapse imaging showed that branched structures arise from plaques by formation and fusion of AChR-poor perforations through a series of steps mirroring that seen in vivo. Multiple fluorophore imaging showed that growth occurs by circumferential, asymmetric addition of AChRs. Analysis in vivo revealed similar patterns of AChR addition during normal development. These results reveal the sequence of steps by which a topologically complex domain forms on a cell and suggest an unexpected nerve-independent role for the postsynaptic cell in generating this topological complexity.

Active zones and receptor surfaces of freeze-fractured crayfish phasic and tonic motor synapses.

Deep and superficial flexor muscles in the crayfish abdomen are innervated respectively by small populations of physiologically distinct phasic and tonic motoneurons. Phasic motoneurons typically produce large EPSP's, releasing 100 to 1000 times more transmitter per synapse than their tonic counterparts, and exhibiting more rapid synaptic depression with maintained stimulation. Freeze-fracturing the abdominal flexor muscles yielded images of phasic and tonic synapse-bearing terminals. The two types of synapse are qualitatively similar in ultrastructure, displaying on the presynaptic membrane's P-face synaptic contacts recognized by relatively particle-free oval plaques which are often framed by the muscle fiber's E-face leaflet with its associated receptor particles. Situated within these presynaptic plaques are discrete clusters of large intramembrane particles, forming active zone (AZ) sites specialized for transmitter release. AZs of phasic and tonic synapses are similar: 80% had a range of 15-40 large particles distributed in either paired spherical clusters or in linear form, with a few depressions denoting sites of synaptic vesicle fusion or retrieval around their perimeters. The packing density of particles is similar for phasic and tonic AZs. The E-face of the muscle membrane displays oval-shaped receptor-containing sites made up of tightly packed intramembranous particles. Phasic and tonic receptor particles are packed at similar densities and the measured values resemble those of several other crustacean and insect neuromuscular junctions. Overall, the similarity between phasic and tonic synapses in the packing density of particles at their presynaptic AZs and postsynaptic receptor surfaces suggests similar regulatory mechanisms for channel insertion and spacing. Furthermore, the findings suggest that morphological differences in active zones or receptor surfaces cannot account for large differences in transmitter release per synapse.