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Central centrifugal cicatricial alopecia (CCCA) is the most common form of primary scarring alopecia diagnosed in women of African descent. Although the etiology was originally attributed exclusively to hairstyling practices common among women of African descent, more recent research on CCCA supports the concept that there are several contributing factors, including variants in gene expression, hair grooming practices that increase fragility on the hair follicle, and associations with other systemic conditions. Treatment of CCCA involves a combination of patient counseling and education on alternative hairstyles, medical therapies, and procedural methods when necessary.

The equilibrium structures and electronic properties such as relative stabilities, electron affinities, and charge transfer of small neutral and charged FeSin(-1,0,+1) (n = 1-6) clusters have been systematically studied using the high level of the correlation consistent Composite Approach (ccCA) method. The lowest-energy geometries of these clusters can be regarded as \"substitutional structure.\" It is derived from Sin + 1(and/or Si-n + 1) clusters by replacing a silicon atom with an iron atom. The adiabatic electron affinities (AEAs) and the adiabatic ionization potentials (AIPs) have also been predicted by ccCA schemes for FeSin(n = 1-6) and their ions. The dissociation energies of an iron or a silicon atom from the ground-state structure of FeSin clusters have been evaluated to check relative stabilities of FeSin(-1,0,+1) (n = 1-6) clusters. Compared with other clusters, neutral and charged FeSi2 possess higher stability. As for the neutral clusters and the negatively charged ions, the theoretical charges of the iron atom in FeSin (n = 1-6) species (except for FeSi and FeSi2-) show that silicon clusters act as an electron donor. For the cationic species, however, the charge transfers from iron atom to silicon clusters (except for FeSi3+) show that the iron atom acts as electron donor.

Ab initio composite approaches have been utilized to model and predict main group thermochemistry within 1 kcal mol-1 , on average, from well-established reliable experiments, primarily for molecules with less than 30 atoms. For molecules of increasing size and complexity, such as biomolecular complexes, composite methodologies have been limited in their application. Therefore, the domain-based local pair natural orbital (DLPNO) methods have been implemented within the correlation consistent composite approach (ccCA) framework, namely DLPNO-ccCA, to reduce the computational cost (disk space, CPU (central processing unit) time, memory) and predict energetic properties such as enthalpies of formation, noncovalent interactions, and conformation energies for organic biomolecular complexes including one of the largest molecules examined via composite strategies, within 1 kcal mol-1 , after calibration with 119 molecules and a set of linear alkanes. © 2019 Wiley Periodicals, Inc.

BACKGROUND: No data exist on the dermatoscopic findings in central centrifugal cicatricial alopecia (CCCA).
OBJECTIVE: We sought to establish the spectrum of dermatoscopic features and their frequency in CCCA.
METHODS: We retrospectively evaluated 153 nonpolarized dermatoscopic images obtained from 51 women with histologically proven CCCA and established a list of 12 dermatoscopic features that were independently scored for each image. Controls included 30 dermatoscopic images from histologically proven cases of scarring traction alopecia and discoid lupus erythematosus. The receiver operating characteristic curve analysis assessed the specificity and sensitivity; Cohen kappa statistics assessed the agreement. Dermatoscopic pathologic correlations were performed on the horizontal sections of 41 of the 51 specimens, which were obtained with dermatoscopy-guided biopsy procedures.
RESULTS: Peripilar white gray halo around the emergence of hairs was observed in 94% of patients and was highly specific and sensitive for CCCA in all clinical stages. It corresponds on pathology to the lamellar fibrosis surrounding the outer root sheath.
CONCLUSIONS: This was a retrospective study.
CONCLUSIONS: The presence of a peripilar white halo is a dermatoscopic feature that suggests the diagnosis of CCCA in African American patients with mild central thinning, and it is an optimal site from which to obtain a biopsy specimen.

BACKGROUND: Most biopsy specimens of cicatricial (scarring) alopecia can be readily subclassified as lymphocytic versus neutrophilic, but specific diagnosis remains difficult, particularly when a late stage of the disease is sampled.
OBJECTIVE: We sought to document patterns of scarring highlighted by elastic tissue staining in primary cicatricial alopecia.
METHODS: We documented Verhoeff elastic van Gieson staining patterns in 58 routinely embedded (vertical) biopsy specimens of cicatricial alopecia. Patterns of fibrosis included perifollicular (wedge-shaped vs broad tree trunk-shaped) and diffuse. The patterns were compared against the diagnosis obtained by independent expert clinical review, including central centrifugal cicatricial alopecia (CCCA), lichen planopilaris, traction alopecia, frontal fibrosing alopecia, discoid lupus erythematosus, and tufted folliculitis.
RESULTS: Wedge-shaped perifollicular fibrosis was seen in lichen planopilaris but also in CCCA. Broad tree trunk-shaped perifollicular fibrosis was most commonly encountered in CCCA.
CONCLUSIONS: The retrospective nature of the study precluded temporal staging of the disease process.
CONCLUSIONS: Patterns of fibrosis highlighted by elastin staining in primary cicatricial alopecia appear to be disease specific. Superficial wedge-shaped perifollicular fibrosis is associated with but may not be specific for lichen planopilaris. Broad tree trunk-like perifollicular fibrosis is specific for CCCA but not present in many cases. Elastin staining represents a useful ancillary study for the evaluation of late-stage scarring alopecia in routinely oriented punch biopsy specimens.

BACKGROUND: Recently, polarized microscopy was reported as helpful in the evaluation of alopecia biopsy specimens.
OBJECTIVE: We sought to determine the usefulness of polarized microscopy relative to elastic tissue staining and fluorescent microscopy.
METHODS: Histologic sections from 60 alopecia specimens were evaluated to determine the pattern of elastic tissue in elastic van Gieson-stained sections. Comparable hematoxylin-eosin sections were examined under a fluorescent microscope to determine the elastic tissue pattern and examined under polarized microscopy to determine the pattern of birefringence.
RESULTS: Elastic van Gieson staining demonstrated high sensitivity (1.0) and high specificity (1.0) for the identification of nonscarring alopecia. In 54 of 60 cases, fluorescent microscopy demonstrated an identical pattern of elastic tissue. High background eosin fluorescence made it impossible to interpret the elastic tissue pattern in the remaining 6 specimens. Strong birefringence in dermal collagen sparing fibrous tracts had high specificity (1.0) but lower sensitivity (0.59). Strong collagen birefringence within the dermis and broad fibrous tracts were present in all 6 cases of central centrifugal cicatricial alopecia.
CONCLUSIONS: Elimination of the 6 uninterpretable specimens with high background fluorescence from our calculations may be a source of bias, as these cases could potentially all have been either negative or positive.
CONCLUSIONS: Elastic tissue staining is the most reliable means to determine the pattern of scarring in alopecia biopsy specimens. In most cases, fluorescent microscopy of hematoxylin-eosin sections shows an identical pattern. Although a pattern of collagen birefringence on polarized microscopy distinctly sparing fibrous tract is specific for nonscarring alopecia, not all cases of nonscarring alopecia demonstrate this pattern. Strong collagen birefringence within both the dermis and fibrous tracts suggests a diagnosis of central centrifugal cicatricial alopecia.