Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hair loss or hair thinning is a common complaint in clinical dermatology, and patients seeking advice for hair loss are not necessarily bald. Also the effects of treatment attempts are hard to measure. Consequently, there is a need for a sensitive tool to monitor hair loss and treatment response. Such a method must be able to analyze the biological parameters of hair growth, which are: 1: hair density (n/cm2), 2: hair diameter (mm), 3: hair growth rate (mm/day) and 4: anagen/telogen ratio. Here we present the TrichoScan as a method which combines epiluminescence microscopy (ELM) with automatic digital image analysis for the measurement of human, and potentially animal hair, in situ. The TrichoScan is able to analyze all biological parameters of hair growth with a so-called intraclass correlation of approx. ninety-one percent with the same TrichoScan operator and an intraclass correlation of approx. ninety-seven percent for different TrichoScan operators. The application of the technique is demonstrated by comparison of the hair parameters in individuals without apparent hair loss with men with untreated AGA and men after treatment with finasteride (1 mg/day), where we were able to detect a significant increase in hair counts and cumulative hair thickness 3 and 6 months after treatment. The advantage of the TrichoScan is that it can be used for clinical studies to compare placebo versus treatment or to compare different capacities of different hair growth promoting substances, it can be used for studying AGA or other forms of diffuse hair loss, and it can be adopted to study the effect of drugs or laser treatment on hypertrichosis or hirsutism.
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PMID:TrichoScan: combining epiluminescence microscopy with digital image analysis for the measurement of hair growth in vivo. 1139 46

In men who are genetically predisposed to develop androgenetic alopecia (AGA; male pattern hair loss), endogenous androgens alter scalp hair follicles, resulting in production of vellus-like, miniaturised hair, rather than cosmetically significant terminal hair. This change leads to a progressive decline in visible scalp hair density, readily perceived by the patient as thinning and, eventually, baldness. Dihydrotestosterone (DHT), a metabolite of testosterone produced by the enzyme 5alpha-reductase, has been implicated as the specific androgen in the pathogenesis of AGA. Men genetically deficient in the Type 2 isoenzyme of 5alpha-reductase do not develop AGA. Moreover, Type 2 5alpha-reductase has been detected in scalp hair follicles, and balding scalps contain increased Type 2 5alpha-reductase activity and DHT levels. Taken together, these findings provide a rationale for the use of Type 2 5alpha-reductase inhibitors in the treatment of men with AGA. Finasteride, a specific and potent inhibitor of human Type 2 5alpha-reductase, decreases the formation of DHT from testosterone. Originally developed for the treatment of men with benign prostatic hyperplasia (BPH) as a 5 mg tablet, finasteride was subsequently evaluated as a treatment for AGA. Clinical studies in balding men demonstrated that finasteride reduced scalp DHT levels and improved hair growth, confirming the role of DHT in the pathophysiology of AGA. Dose-ranging studies established the optimal dose of 1 mg/day for the treatment of men with this disorder. Large, multicentre studies established the safety and efficacy of finasteride 1 mg, leading to marketing of Propecia (finasteride 1 mg) as a new treatment for men with AGA.
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PMID:Finasteride, a Type 2 5alpha-reductase inhibitor, in the treatment of men with androgenetic alopecia. 1599 88

Androgenetic alopecia is one of the most common diagnoses in a hair clinic. It is non-scarring pattern hair losses that affect individuals, independent on severity, age and gender. The incidence of AGA increases within the age. AGA affects women less frequently, is usually milder and is associated with diffuse thinning of the hair scalp. Prompt diagnosis and treatment are essential for obtaining optimal outcome.
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PMID:[Androgenetic alopecia in women]. 2872 58

Introduction: Androgenetic alopecia is a common hair loss disorder affecting up to 80% of males by the age of 80. It is characterized by androgen related progressive thinning of hair in a defined pattern. It results in diminished self-esteem, reduced confidence and distress in affected men, irrespective of age or stage of baldness. An effective treatment for hair baldness is needed.Areas covered: In androgenetic alopecia, hair follicles undergo progressive miniaturization. Genetic factors and androgens are key role-players in disease pathogenesis. Herein the authors review the pharmacologic treatment of androgenetic alopecia, which involves 5 alpha reductase inhibitors, minoxidil and prostaglandins. Non-pharmacologic approaches are also explored.Expert opinion: Androgenetic alopecia progresses over time and although the current available medical treatments like finasteride and minoxidil are effective in arresting the progression of the disease, they allow only partial regrowth of hair at its best. Early treatment achieves a more optimal outcome. Non-pharmacologic treatments like PRP can be considered in patients refractory to medical treatment.Abbreviations: MPHL: male pattern hair loss; AGA: androgenetic alopecia; DHT: dihydrotestosterone; 5AR: 5-alpha-reductase; VEGF: vascular endothelial growth factor; PG's: prostaglandins (PG's); PGD2R: prostaglandin D2 receptor; VPA: valproic aid; SR: Serenoa Repens; PRP: platelet-rich plasma; PDGF: platelet derived growth factor; TGF: transforming growth factor; ERK: extracellular signal-regulated kinase; PKB: protein kinase B; LLLT: low-level laser therapy; ROS: reactive oxygen species; RCT: randomized control trial; SFRP1: secreted frizzled related protein 1; DP: dermal papilla; PDE5: phosphodiesterase 5.
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PMID:A review of the treatment of male pattern hair loss 3206 84