Why human prepuce is a valuable resource in science? Histological, ultrastructural, immunohistochemical and statistical analysis / ¿Por qué el prepucio humano es un recurso valioso en la ciencia? Análisis histológicos, ultraestructurales, inmunohistoquímicos y estadísticos

SUMMARY: This research was to examine the histological and ultrastructural characteristics of prepuce samples, as well as vimentin and S100 protein localization and statistical analysis. Urologists have long struggled with the prepuce, which is used to treat a variety of urethral problems. Skin biopsies were collected from the prepuce at the moment of circumcision and processed for light microscopy, electron microscope examination, immunohistochemical techniques, and statistical analysis in a total of six boys. Histologically, the prepuce epidermis displayed focal spiky ridges, which are saw-toothed interspersed with sulci, slight hyperpigmentation, looser connective tissue and plentiful vascular components. Immunohistochemically, the existence of melanocytes and Langerhans cells in the epidermis, as well as smooth muscles in the dermis, was stained positively for vimentin. Also, there was a positive reactivity of the Langerhans cells in the epidermis and around Meissner's corpuscles in the dermis for S100 protein staining. Ultrastructurally, the prepuce's intercellular gaps were widened, melanocytes rested on a folded basement membrane, and desmosomal content was reduced, with a prominent active euchromatic nucleus. Cytoplasmic projections were distended and elongated, and the interstitial blood vessels were surrounded by endothelial cells and rested on a basement membrane. There were also minimal collagen fibers in the interstitium. The prepuce's histological and ultrastructural features, as well as immunohistological studies using vimentin and S100 protein as intermediate filaments and statistical analysis, all demonstrated that it is a useful scientific resource.

RESUMEN: El presente trabajo de investigación se realizó para examinar las características histológicas y ultraestructurales de las muestras de prepucio, así como la localización y el análisis estadístico de la vimentina y la proteína S100. Los urólogos han intentado trabajar durante mucho tiempo con el prepucio, que se usa para tratar una variedad de problemas uretrales. Se recolectaron biopsias de piel del prepucio de seis niños en el momento de la circuncisión y se procesaron para microscopía óptica, examen con microscopio electrónico, técnicas inmunohistoquímicas y análisis estadístico. Histológicamente, la epidermis del prepucio mostraba crestas puntiagudas focales, intercaladas con surcos, hiperpigmentación leve, tejido conectivo más laxo y abundantes componentes vasculares. Inmunohistoquímicamente, la existencia de melanocitos y células dendríticas epidérmicas (células de Langerhans), así como músculo liso en la dermis, se tiñeron positivamente para vimentina. Además, hubo una reactividad positiva de las células dendríticas epidérmicas en la epidermis y alrededor de los corpúsculos del tacto (de Meissner) en la dermis para la tinción de la proteína S100. Ultraestructuralmente, los espacios intercelulares del prepucio se ensancharon, los melanocitos descansaban sobre una membrana basal plegada y el contenido desmosómico se redujo, con un núcleo eucromático activo prominente. Las proyecciones citoplasmáticas estaban distendidas y alargadas, y los vasos sanguíneos intersticiales estaban rodeados por células endoteliales y descansaban sobre una membrana basal. También había fibras de colágeno mínimas en el intersticio. Las características histológicas y ultraestructurales del prepucio, así como los estudios inmunohistológicos utilizando vimentina y proteína S100 como filamentos intermedios y el análisis estadístico, demostraron que es un recurso científico útil.

Canine perineal hypospadias / Hipospadia perineal canina

Canine hypospadias is a rare condition that can occur in male and female dogs. Affected animals may present signs of urinary incontinence, recurrent urinary tract infections, periurethral dermatitis or can remain asymptomatic. Periurethral hypospadias in a 14-week-old mongrel dog and its surgical repair are addressed.

Hipospadia canina é uma condição rara que pode ocorrer em cães machos e fêmeas. Animais afetados podem apresentar sinais de incontinência urinária, infecções recorrentes do trato urinário, dermatite periuretral ou podem permanecer assintomáticos. Hipospadia periuretral em cão de 14 semanas de idade, sem raça definida, e sua reparação cirúrgica são abordadas.

HIV-1 transmission in the male genital tract.

HIV-1 is mainly a sexually transmitted infection, and epithelial surfaces covering genital mucosa are the primary site of HIV-1 transmission. Although male circumcision was reported to reduce male acquisition of HIV-1 by 60%, the initial mechanisms of HIV-1 transmission in the male genitals remain elusive. We established two novel models of the adult human foreskin epithelium that allowed for polarized infection via the mucosal pole with either HIV-1-infected cells that are present in all secretions vectorizing HIV-1 or cell-free HIV-1. Efficient HIV-1 transmission occurs following 1 hr of polarized exposure of the inner, but not outer, foreskin to mononuclear cells highly infected with HIV-1, but not to cell-free virus. HIV-1-infected cells form viral synapses with apical foreskin keratinocytes, leading to polarized budding of HIV-1, which is rapidly internalized by Langerhans cells (LCs) in the inner foreskin. In turn, LCs form conjugates with T-cells, thereby transferring HIV-1. Seminal plasma from HIV-negative men mixed with cervico-vaginal secretions from HIV-positive women, which mimics the in-vivo mixture of these genital fluids during woman-to-man HIV-1 sexual transmission, decreases HIV-1 infection at the foreskin. Our results rationalize at the cellular level the apparent protective outcome of circumcision against HIV-1 acquisition by men.

Absence of lymphatic vessels in human dental pulp: a morphological study.

Few and controversial data are available in the literature regarding the presence of lymphatic vessels in the human dental pulp. The present study was designed to examine morphologically the existence of a lymph drainage system in human dental pulp. Human dental pulp and skin sections were immunohistochemically stained with specific antibodies for lymphatic endothelium (D2-40, LYVE-1, VEGFR-3 [vascular endothelial growth factor receptor-3], and Prox-1), with the pan-endothelial markers CD31 and von Willebrand factor (vWF), and with the blood-specific marker CD34. Several blood vessels were identified in human pulps and skin. Lymphatic vessels were found in all human skin samples but in none of the pulps examined. Western blotting performed on human dermis and on pulps treated with collagenase (to remove odontoblasts) confirmed these results. Transmission electron microscopy indicated that vessels which, by light microscopy, appeared to be initial lymphatic vessels had no anchoring filaments or discontinuous basement membrane, both of which are typical ultrastructural characteristics of lymphatic vessels. These results suggest that under normal conditions human dental pulp does not contain true lymphatic vessels. The various theories about dental pulp interstitial fluid circulation should be revised accordingly.

Fimose: conceitos e atualidades / Phymosis: concepts and uptodates

Fimose é condição comum nos consultórios pediátricos. Por tratar-se, possivelmente, de evento fisiológico na vida da criança e, muitas vezes, não precisar de tratamento é fundamental diferenciar as situações patológicas e fisiológicas. Este artigo trata de questões como conceitos, classificação e indicações para o tratamento clínico ou cirúrgico. Explorando opções desses tratamentos, discutimos o sucesso e as principais complicações dos mesmos. Além disso, faz-se breve análise da relação custo-benefício entre os tratamentos.

Foreskin surface area and HIV acquisition in Rakai, Uganda (size matters).

INTRODUCTION: Male circumcision reduces HIV acquisition in men. We assessed whether foreskin surface area was associated with HIV acquisition prior to circumcision. METHODS: In two randomized trials of male circumcision, the surface area of the foreskin was measured after surgery using standardized procedures. Nine hundred and sixty-five initially HIV-negative men were enrolled in a community cohort who subsequently enrolled in the male circumcision trials, provided 3920.8 person-years of observation prior to circumcision. We estimated HIV incidence per 100 person-years prior to circumcision, associated with foreskin surface area categorized into quartiles. RESULTS: Mean foreskin surface area was significantly higher among men who acquired HIV (43.3 cm2, standard error 2.1) compared with men who remained uninfected (36.8 cm, standard error 0.5, P = 0.01). HIV incidence was 0.80/100 person-years (8/994.9 person-years) for men with foreskin surface areas in the lowest quartile (< or =26.3 cm2), 0.92/100 person-years (9/975.3 person-years) with foreskin areas in the second quartile (26.4-35.0 cm2), 0.90/100 person-years (8/888.5 person-years) with foreskin area in the third quartile (35.2-45.5 cm2) and 2.48/100 person-years (23/926.8 person-years) in men with foreskin surfaces areas in the highest quartile (>45.6 cm2). Compared with men with foreskin surface areas in the lowest quartile, the adjusted incidence rate ratio of HIV acquisition was 2.37 (95% confidence interval 1.05-5.31) in men with the largest quartile of foreskin surface area. CONCLUSION: The risk of male HIV acquisition is increased among men with larger foreskin surface areas.