Single rooted primary mandibular first molar is a rare developmental anomaly. Literatures reveal that failure of invagination of Hertwig's epithelial root sheath leads to this unusual root form. Thorough knowledge of root canal morphology and anatomical variations of primary teeth can help a pediatric dentist in successful root canal treatment. Hereby, we describe two cases of primary mandibula...

Hidradenitis suppurativa (HS) is a chronic debilitating disease characterized by inflammatory nodules and sinus tracts in areas rich terminal hair follicles apocrine glands. Lifestyle factors associated with oxidative stress, such as obesity smoking, worsen symptoms. An early step HS follicular dilation occlusion keratin, which results rupture robust response. Nrf2 signaling key regulator of re...

Hamartomas are composed of cells native to an organ but abnormal in number, arrangement or maturity. In the tuberous sclerosis complex (TSC), hamartomas develop in multiple organs because of mutations in TSC1 or TSC2. Here we show that TSC2-null fibroblast-like cells grown from human TSC skin hamartomas induced normal human keratinocytes to form hair follicles and stimulated hamartomatous chang...

We examine the Hoxc12 RNA expression pattern during both hair follicle morphogenesis and cycling in direct comparison to its only upstream neighbor, Hoxc13. Expression of both genes is restricted to the epidermal part of the follicle excluding the outer root sheath and interfollicular epidermis in a distinct stage-dependent and cyclical manner. During the progressive growth phase (anagen) of de...

We report the presence of pluripotent neural crest stem cells in the adult mammalian hair follicle. Numerous neural crest cells reside in the outer root sheath from the bulge to the matrix at the base of the follicle. Bulge explants from adult mouse whisker follicles yield migratory neural crest cells, which in clonal culture form colonies consisting of over a thousand cells. Clones contain neu...

Proliferating trichilemmal tumor (PTT), still referred to as proliferative trichilemmal cyst (TC), is an uncommon malignant adnexal tumor originating from the cells of the outer root sheath of the hair follicle or, more often, from a trichilemmal cyst, following multiple trauma and/or recurrent inflammation. We report the case of a 64-year old female patient, with no particular previous history...

A good knowledge of the parameters causing casing damage is critically important due to vital role of casing during the life of a well. Cement sheath, which fills in the gap between the casing and wellbore wall, has a profound effect on the resistance of the casing against applied loads. Most of the empirical equations proposed to estimate the collapse resistance of casing ignore the effects of...

A major cytoskeletal and extracellular matrix proteins of the amphioxus notochordal cells and sheath were detected by immunohistochemical techniques. The three-layered amphioxus notochordal sheath strongly expressed fish collagen type I in its outer and middle layers, while in the innermost layer expression did not occur. The amphioxus notochordal sheath was reactive to applied anti-human antib...

The contractile tail of bacteriophage T4 is a molecular machine that facilitates very high viral infection efficiency. Its major component is a tail sheath, which contracts during infection to less than half of its initial length. The sheath consists of 138 copies of the tail sheath protein, gene product (gp) 18, which surrounds the central non-contractile tail tube. The contraction of the shea...

In this study cauda epididymal spermatozoa of rats maintained on a selenium-deficient diet for 5 and 7 months exhibited an array of flagellar defects. Spermatids and spermatozoa were analyzed by light and electron microscopy to define the appearance of flagellar abnormalities during spermiogenesis and post-testicular sperm development. Late spermatids of selenium-deficient rats displayed normal...