Med Science

This patient's findings of enteropathy, eczema, failure to thrive, and a mutation in the FOXP3 gene are diagnostic of IPEX syndrome.

Medulloblastoma Cranial MRI (T1-weighted, with contrast) There is a mass in the posterior cranial fossa. It features solid parts (green overlay) and cystic parts (red overlay). Location and appearance are typical of a medulloblastoma. (D: diencephalon; P: pons; C: cerebellum; yellow outline: cerebellar tentorium)

▓▓▓▓▓▓▓▓▓▓▓▓░░░░░░░░ 61%

Serine for ach receptors

Tyrosine for thyroid hormones

Adolescents who are suspected of substance use disorder can be quickly screened using the CRAFFT questionnaire. The CRAFFT questionnaire involves six questions: • C: Have you ever driven a car while high or ridden in a car with someone who was high? • R: Do you ever use alcohol or drugs to relax, feel better about yourself, or fit in? • A: Do you ever use alcohol or drugs when alone? • F: Do you ever forget things you did while using alcohol or drugs? • F: Do your family or friends ever tell you to cut back on your drinking or drug use? • T: Have you ever gotten into trouble while you were using alcohol or drugs? Adolescents who answer affirmatively to ≥ 2 of these questions should be assessed further for substance use disorder, and treatment should be recommended accordingly. Even if an adolescent does not answer affirmatively to any of these questions, CRAFFT‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌ can be used as an opportunity for further education on drug use.

Not hard

Neuroblastoma A malignant neuroendocrine tumor of the sympathetic nervous system that originates from neural crest cells. Primarily affects children and infants. Composed of blastematous, stromal, and/or epithelial components. Diagnosed by increased urinary catecholamines.

BP is caused by autoantibodies against hemidesmosomes, structural components which anchor the basal layer of epithelial cells to the basement membrane.  These autoantibodies result in a destructive inflammatory cascade that causes the entire epidermis to separate from the dermis, forming subepidermal blisters.  In addition to skin biopsy for routine histology and immunofluorescence, serologic testing for autoantibodies against hemidesmosome proteins (eg, BP180, BP230) is also obtained to confirm the diagnosis.

#ethics

Gastric adenocarcinoma often involves loss of CDH1, the gene encoding E-cadherin, a cell adhesion molecule critical for maintaining epithelial integrity. This loss contributes to tumor invasiveness and metastasis. Other molecular changes include abnormal APC, KRAS, and TP53 gene activity, along with increased angiogenic and growth signaling. Gastric cancer may present late with nonspecific symptoms; early detection requires endoscopy and biopsy.

Osteochondroma Which develops in the metaphysis of long bones (e.g., proximal humerus, distal femur), is the most common benign bone tumor. Osteochondromas have a peak incidence between 10 and 30 years of age and most commonly affect male individuals. While most affected individuals present with a painless palpable mass near a joint, they can also develop localized pain, limited range of motion, bone deformities, and pathologic fractures. Characteristic radiographic findings include a pedunculated or sessile bony protrusion with a cartilage cap.

Mechanism of action: immunosuppressants Mycophenolate mofetil (MMF) acts by inhibiting inosine monophosphate dehydrogenase (IMPDH), resulting in selective inhibition of lymphocyte proliferation. Azathioprine (AZA) is a purine analog that is converted, first, to 6-mercaptopurine and, then, into thioinosine monophosphate (TIM), a cytotoxic agent, which acts to block nucleotide synthesis and inhibit lymphocyte proliferation. Methotrexate (MTX) is a folic acid antagonist (antimetabolite), which acts primarily by inhibiting the clonal expansion of B and T cells. Cyclophosphamide causes alkylation of DNA/RNA, resulting in impaired DNA cross-linking and DNA synthesis. Basiliximab/daclizumab inhibits the alpha chain (CD25 antigen) of the IL-2 receptor of T cells, resulting in a reduction of T-cell responses and the expansion of natural killer cells. Sirolimus/everolimus inhibits mTOR kinase resulting in the inhibition of the IL-2-mediated cell cycle. This leads to reduced T-cell activation and B-cell differentiation, resulting in decreased IgM, IgG, and IgA production. Tacrolimus (FK 506) and pimecrolimus bind to the FK506 binding protein (FKBP) resulting in inhibition of calcineurin, an enzyme necessary for the activation of NFAT. This leads to reduced gene transcription and activation of T cells. Cyclosporine A binds cyclophilin, which also inhibits calcineurin. Glucocorticoids (corticosteroids) directly inhibit intracellular NF-κB, a protein complex responsible for transcription of DNA, cytokine production, and cell survival.