Cetacean epidermal specialization: A review.

Cetacean skin continues to be the investigative focus of researchers from several different scientific disciplines. Yet, most research on the basic functions of lipo-keratinocytes, which constitute most of the cetacean epidermis, providing the first layer of protection against various environmental aggressors (including an ever-increasing level of pollutants), is restricted to specialized literature on the permeability barrier only. In this review, we have attempted to bring together much of the recent research on the functional biology of cetacean skin, including special adaptations at the cellular, genetic and molecular level. We have correlated these data with the cetacean permeability barrier's unique structural and metabolic adaptations to fully aquatic life, including the development of secondary barriers to ward off challenges such as biofouling as well as exposure to extreme cold for the epidermis, which is outside of the insulation provided by blubber. An apparent contradiction exists between some of the reported gene loss for lipogenic enzymes in cetacean skin and the high degree of cetacean epidermal lipogenesis, as well as loss of desmocollin 1 and desmoplakin genes [while immunolocalization of these proteins is reported (Journal of Anatomy, 234, 201)] warrants a re-evaluation of the gene loss data.

Unique features of the skin barrier in naked mole rats reflect adaptations to their fossorial habitat.

The stratum corneum (SC), the top layer of the epidermis, is the functional site of the skin barrier and serves to maintain hydration of the body by preventing water loss and thwarting the entrance of pathogens. The naked mole rat (NMR) (Heterocephalus glaber) is a rodent that resides in hypoxic underground tunnels in arid Africa. NMRs are not only hairless; their skin is devoid of glands and pain sensation. To understand how the skin barrier of the NMR is uniquely adapted to this environment, skin samples from the dorsum and ventral abdomen in one adult and one neonate were examined by transmission electron microscopy using both reduced osmium tetroxide to assess overall structure and ruthenium tetroxide post-fixation to assess lipid organization. These findings were compared with that of hairless mice-a well-defined model for skin barrier studies. The plasticity of the skin was evaluated on 10 NMRs from a colony at the Philadelphia Zoo in humid and dry conditions by measuring cutaneous hydration, transepidermal water loss (TEWL), and pH. The epidermal ultrastructure of the NMR differed from hairless mice by having the following features: decreased content of lamellar bodies (LBs), higher LB pleomorphism, periodic presence of abnormal lipid bilayers, and an unusually thick SC. The NMRs developed significant TEWL and a trend toward decreased hydration when subjected to dry conditions. While these features illustrate an imperfect skin barrier in terrestrial mammals, they likely represent adaptations of the poikilothermic NMRs to their unique natural fossorial climate. Prolonged exposure to decreased humidity could possibly lead to adverse health effects in this species.

Structure and function of skin in the pelagic sea snake, Hydrophis platurus.

We describe and interpret the functional morphology of skin of the Yellow-bellied sea snake, Hydrophis platurus. This is the only pelagic sea snake, and its integument differs from what is known for other species of snakes. In gross appearance, the scales of H. platurus consist of non-overlapping, polygonal knobs with flattened outer surfaces bearing presumptive filamentous sensillae. The deep recesses between scales ('hinge') entrap and wick water over the body surface, with mean retention of 5.1 g/cm of skin surface, similar to that determined previously for the roughened, spiny skin of marine file snakes, Acrochordus granulatus. This feature possibly serves to maintain the skin wet when the dorsal body protrudes above water while floating on calm oceanic slicks where they forage. In contrast with other snakes, including three species of amphibious, semi-marine sea kraits (Laticauda spp.), the outer corneous ß-protein layer consists of a syncytium that is thinner than seen in most other species. The subjacent α-layer is also thin, and lipid droplets and lamellar bodies are seen among the immature, cornifying α-cells. A characteristic mesos layer, comprising the water permeability barrier, is either absent or very thin. These features are possibly related to (1) permeability requirements for cutaneous gas exchange, (2) reduced gradient for water efflux compared with terrestrial environments, (3) less need for physical protection in water compared with terrestrial ground environments, and (4) increased frequency of ecdysis thought to be an anti-fouling mechanism. The lipogenic features of the α-layer possibly compensate for the reduced or absent mesos layer, or produce layers of cells that comprise what functionally might be termed a mesos layer, but where the organization of barrier lipids nonetheless appears less robust than what is characteristically seen in squamates.

An overview of epidermal lamellar bodies: Novel roles in biological adaptations and secondary barriers.

The epidermal lamellar bodies (LBs) are specialized organelles that contain pro-barrier lipids imparting a fully lamellar internal structure, but also other cargoes such as enzymes (lipid metabolizing and proteolytic), enzyme inhibitors, and antimicrobial peptides. Thus, the LB secretory system, by virtue of delivering these cargoes to the stratum corneum (SC) interstices, is essential for forming the various skin barriers located in the SC. Ultrastructural studies have suggested that the morphologic features of LBs reflect the functional status of the SC. Several ichthyotic skin diseases as well as experimental animal models with defective epidermal lipogenesis show only partial lamellar contents or even empty appearing LB, reflecting an abnormal cargo composition. We suggest that LB polymorphism reflects a wide array of barrier adaptations to environmental challenges, rather than just a defective barrier function, based on observations on a) LB morphology in inherited skin disorders of lipid metabolism (Refsum disease, Chanarin-Dorfman syndrome) characterized by deficiency of lamellar lipids and accumulation of toxic metabolites; b) Psoriasis (with a high expression of Psoriasin antimicrobial peptide within lesions) and c) the Pitohui, a toxic bird where diet-derived toxin is eliminated via the LB secretory system that creates a chemical defense system. Morphological features of LBs from these models suggest a hitherto unrecognized function for the LBs in elimination of toxic substances from the body. We also provide preliminary evidence that indicate yet another function for the LBs- as a type of recycling endosomes allowing for uptake of certain topically applied materials by the epidermis.

Idiopathic chondrolysis of hip in children: New proposal and implication for radiological staging.

PURPOSE: Our objective was to evaluate the radiological appearances in different stages of idiopathic chondrolysis of hip (ICH) which will be helpful in the early diagnosis and guiding appropriate treatment for this condition to prevent progression of disease. MATERIALS AND METHODS: We evaluated 14 patients of ICH in varying stages: Stage 1 (n = 9), Stage 2 (n = 3), Stage 3 (n = 2). Average age at presentation was 10-11 years. Plain radiograph and magnetic resonance imaging (MRI) was done in all these patients. RESULTS: In the current study, we have attempted to stage ICH based on the radiological progression of the disease, where MRI was used as the primary tool. Stage 1 showed a wedge-shaped hyperintensity in T2 weighted (T2W) and hypointensity in T1 weighted (T1W) images involving the middle one-third of the femoral head and it is the earliest and characteristic finding in MRI. Associated findings like joint space narrowing, synovial hypertrophy with joint effusion may also be observed. Stage 2 showed acetabular edema in the affected hip in addition to the above-mentioned findings. Stage 3 showed more extensive involvement of femoral head and acetabulum, with collapse of the femoral head, degenerative changes in hip, early osteoporotic changes, and ultimately loss of joint space. CONCLUSION: Imaging-based staging system proves very useful in the early diagnosis, staging, and assessing the prognosis of ICH.

Autosomal Recessive Keratoderma-Ichthyosis-Deafness (ARKID) Syndrome Is Caused by VPS33B Mutations Affecting Rab Protein Interaction and Collagen Modification.

In this paper, we report three patients with severe palmoplantar keratoderma associated with ichthyosis and sensorineural deafness. Biallelic mutations were found in VPS33B, encoding VPS33B, a Sec1/Munc18 family protein that interacts with Rab11a and Rab25 proteins and is involved in trafficking of the collagen-modifying enzyme LH3. Two patients were homozygous for the missense variant p.Gly131Glu, whereas one patient was compound heterozygous for p.Gly131Glu and the splice site mutation c.240-1G>C, previously reported in patients with arthrogryposis renal dysfunction and cholestasis syndrome. We demonstrated the pathogenicity of variant p.Gly131Glu by assessing the interactions of the mutant VPS33B construct and its ability to traffic LH3. Compared with wild-type VPS33B, the p.Gly131Glu mutant VPS33B had reduced coimmunoprecipitation and colocalization with Rab11a and Rab25 and did not rescue LH3 trafficking. Confirming the cell-based experiments, we found deficient LH3-specific collagen lysine modifications in patients' urine and skin fibroblasts. Additionally, the epidermal ultrastructure of the p.Gly131Glu patients mirrored defects in tamoxifen-inducible VPS33B-deficient Vps33bfl/fl-ERT2 mice. Both patients and murine models revealed an impaired epidermal structure, ascribed to aberrant secretion of lamellar bodies, which are essential for epidermal barrier formation. Our results demonstrate that p.Gly131Glu mutant VPS33B causes an autosomal recessive keratoderma-ichthyosis-deafness syndrome.

Effects of Extracellular Calcium and 1,25 dihydroxyvitamin D3 on Sebaceous Gland Cells In vitro and In vivo.

Calcium and 1,25 dihydroxyvitamin D3 (1,25(OH)2D3) are promoters of epithelial cell functions; however their effects on sebaceous glands are unknown. In this study, morphology, ultrastructure, cell numbers, lipid synthesis and apoptosis of SZ95 sebocytes were assessed in vitro under different concentrations of extracellular calcium with or without 1,25(OH)2D3. Moreover, serum calcium and 1,25(OH)2D3 levels were assessed in acne and non-acne patients (controls). Under conditions of low extracellular calcium, lipogenesis and cell detachment were observed. Increasing extracellular calcium enhanced sebocyte numbers, induced epithelial morphology and reduced lipogenesis. Moreover, a reduction in extracellular calcium reduced E-cadherin and enhanced caspase 3/7 activity (apoptosis), whereas calcium chelation by EGTA (ethylene glycol-bis(ß-aminoethyl ether)-N,N,N',N'-tetraacetic acid) resulted in enhanced lipogenesis. 1,25(OH)2D3 decreased sebaceous lipogenesis, but also induced signs of autophagy. In the clinical study, patients and controls exhibited normal serum calcium levels. Younger acne patients presented lower 1,25(OH)2D3 levels than did older ones. In conclusion, extracellular calcium and 1,25(OH)2D3 regulate sebocyte morphology, increase cell numbers, decrease sebaceous lipogenesis and induce cell autophagy in vitro. The increased ionized calcium and the reduced 1,25(OH)2D3 levels detected in the serum of younger patients with acne may contribute respectively to increased sebaceous gland volume and enhanced lipogenesis.

Neonatal parechovirus leucoencephalitis- radiological pattern mimicking hypoxic-ischemic encephalopathy.

AIM: Our objective is to study the MR imaging pattern in neonatal parechoviral leucoencephalitis, a rare cause of neonatal white matter abnormality and to differentiate it from hypoxic-ischemic encephalopathy which is the commonest cause of white matter change in neonates. METHOD: We evaluated 25 neonates who presented with features of encephalopathy. Cranial ultrasound and MR imaging was done in all the cases. The pattern of white matter abnormality was analyzed in all cases. RESULTS: Neonatal leucoencephalitis caused by HPeV has a distinctive clinical presentation and has predilection for the white matter, causing diffusion restricting signal intensity changes involving the periventricular and subcortical white matter, in particular the frontal white matter, also the corpus callosum, internal capsule, external capsule and pyramidal tracts of the supratentorial brain and cerebral peduncle with relative sparing of occipital white matter, thalamus, basal ganglia and the infratentorial regions. Follow up imaging shows disappearance of the lesion without white matter loss. Whereas mild to moderate hypoxic-ischemic injury in a full-term neonate causes lesions in the watershed areas, and subcortical white matter predominantly involving the parietooccipital region and perirolandic region. Thalamus, brainstem, cerebellum, and deep gray matter structures are involved depending on the severity. CONCLUSION: White matter changes in the neonatal period are commonly associated with hypoxic-ischemic injuries and metabolic causes, less frequently, infection like parechovirus leucoencephalitis. HPeV infection must be considered in infants with specific pattern of white matter change but no convincing history of a perinatal hypoxic-ischemic insult, thus differentiating it from HIE.

A Japanese Encephalitis Vaccine From India Induces Durable and Cross-protective Immunity Against Temporally and Spatially Wide-ranging Global Field Strains.

BACKGROUND: Japanese encephalitis (JE) is a vaccine-preventable acute disease. We report the results of a phase 2/3 trial of JENVAC, a Vero cell-derived vaccine developed using an Indian strain of JE virus (JEV). METHODS: JENVAC was administered in 2 doses 28 days apart, and immunogenicity was compared to that from a single dose of SA-14-14-2, the only approved JE vaccine and regimen at the time in India. RESULTS: After both the doses, seroconversion and seroprotection were >90% for JENVAC. For SA-14-14-2, seroconversion and seroprotection were 57.69% and 77.56%, respectively, on day 28 and 39.74% and 60.26%, respectively, on day 56. The geometric mean titers at day 28 and day 56 were 145.04 and 460.53, respectively, for JENVAC and 38.56 and 25.29, respectively, for SA-14-14-2. With a single dose of JENVAC, seroprotection titers lasted at least 12 months in >80% of the subjects. Following receipt of 2 doses, 61.17% of subjects retained seroprotection titers at 24 months, and immunogenicity criteria were higher than that for SA-14-14-2 at 12, 18, and 24 months each. Sera from JENVAC subjects neutralized JEV genotypes I, II, III, and IV equally well. Adverse events were not significantly different between the 2 vaccines. CONCLUSIONS: JENVAC elicits long-lasting, broadly protective immunity. CLINICAL TRIALS REGISTRATION: CTRI/2011/07/001855.

A 'toxin mantle' as defensive barrier in a tropical bird: evolutionary exploitation of the basic permeability barrier forming organelles.

Birds in the genus Pitohui and Ifrita carry potent neurotoxins that are most abundant in skin and feathers. It was unknown precisely how or where in the skin these chemicals are stored. Here, we report high-resolution electron microscopy using OsO4 staining to visualize the location of alkaloids. Our images suggest that toxic alkaloids accumulate in multigranular bodies of epidermal cells and are likely secreted as part of the avian epidermal barrier, where they are made available for chemical defense.

Correlation of age and antimullerian hormone in assisted reproductive technology program outcome.

Increasing female literacy and employment have resulted in a clear rise in the age at which women conceive. As fertility starts to decline with advancing age more and more number of women are facing the problem of infertility and are seeking medical attention to over come this problem. This resulted in more number of women seeking medical help to over come the problem of Infertility. This age related decline in ovarian reserve is not uniform in all women of reproductive age. A number of ovarian reserve tests were developed to overcome this problem. But to date there is no ideal marker for predicting ovarian reserve and pregnancy outcome in assisted reproductive technology program (ART). Recent studies indicate that anti mullein hormone is a promising marker for predicting ovarian reserve and pregnancy out come. The aim of this study was to assess the influence of age on Anti-Mullerian Hormone (AMH) in ART program outcomes. Ninety-three subjects in the age group of 25 to 42 years were recruited to the study. All these subjects underwent controlled ovarian stimulation (COS) and later intracytoplasmic sperm injection (ICSI). Subjects were divided into four groups. AMH levels in positive and negative pregnancy subjects in the above and below 35years age groups were compared. AMH levels were correlated with other ovarian reserve parameters and clinical pregnancy out come in both the age groups. Statistically significant differences were found in AMH levels between positive and negative pregnancy subjects in the age group of 35 and above, but not in the age group below 35 years. There were positive correlations between AMH and other ovarian reserve markers and clinical pregnancy outcome in this age group. AMH and the number of retrieved oocytes (r = 0.784, P < 0.01), Antral Follicle count (AFC) (r = 0.749, P < 0.01) and Mature Oocytes (MII) (r = 0.407, P < 0.01) followed by Grade-I Embryos (r = 0.433, P < 0.01). The current study revealed that AMH levels are better correlated with ovarian reserve and clinical pregnancy out come in subjects aged 35 years and above.

The structure and function of the stratum corneum.

Over the past 150 years the skin's structure and function has been the subject of much investigation by scientists. The stratum corneum (SC), the skin's outermost layer and interface with the outside world is now well recognized as the barrier that prevents unwanted materials from entering, and excessive loss of water from exiting the body. This review summarizes the major advances in our understanding of this formidable membrane. The structure of the SC is outlined as well as techniques to visualize the barrier. The lipid organization and ionic gradients, as well as the metabolic responses and underlying cellular signalling that lead to barrier repair and homeostasis are discussed. Finally, a brief overview of the molecular and genetic factors that determine the development of a competent permeability barrier is provided.

A child with serious Chikungunya virus (CHIKV) infection requiring intensive care, after an outbreak.

A 5 1/2-yr-old boy presented with high grade fever for 4 days, and cervical adenitis, body ache, arthralgia, followed by sudden onset of breathlessness. He had clinical, electrocardiographic and echo evidence of myocarditis and congestive cardiac failure. An enzyme-linked immunosorbent assay (MAC-IgM ELISA) with serum collected 5 days after disease onset showed IgM antibodies to CHIKV. He was managed conservatively and started showing symptomatic improvement by 3 days. At discharge, a repeat Echocardiogram (a week later) showed normal left ventricular (LV) function with mild Mitral regurgitation. On follow up, after 2 months, child remains asymptomatic. Other common aetiological agents were screened for and found negative. This may indicate a probable cardiac tropism for the virus.

Mitochondria: a new focus as an anti-aging target in skin care.

Mitochondria, long considered to have the primary role in cellular energetic, have been the center of much research interest in the recent past. Technological advances in microscopy and development of new and specific fluorescent dyes for visualization of mitochondrial dynamics in living cells have facilitated the newfound interest in these fascinating organelles, which are now implicated in diverse cellular functions crucial in health and disease. Mitochondria play crucial roles in several age-related diseases, and in the physiology of normal aging. In this review, we discuss the structural and functional aspects of mitochondria and their implications to the aging process, as well as its significance to skin aging. Available information on active molecules that can impact the mitochondrial functions, and their potential use in skin care products is also discussed, highlighting these organelles as a new focus for anti-aging strategies in personal care.

Penetration pathways induced by low-frequency sonophoresis with physical and chemical enhancers: iron oxide nanoparticles versus lanthanum nitrates.

Low-frequency sonophoresis (LFS) has been shown to disrupt the structure of stratum corneum (SC) lipid bilayers and enhance SC permeability. In this study, we examined the penetration pathway of lanthanum nitrate (LaNO(3)) tracer in viable epidermis after combined treatment of LFS and tape stripping (TS), as a physical enhancer, or oleic acid (OA) application, as a chemical enhancer, using transmission electron microscopy (TEM). As a positive control, we visualized the passive diffusion pathway of LaNO(3) and iron oxide (Fe(3)O(4)) nanoparticles after the incision of hairless mouse skin. Next, we applied LFS immediately after TS or OA application and visualized the penetration pathway of LaNO(3). Each treatment showed restricted penetration to the SC-stratum granulosum (SG) interface or upper SG layer. However, the additional application of LFS induced diffuse intracellular distribution of LaNO(3) throughout the viable epidermis. Quantitative analysis also revealed that combined treatment significantly increases LaNO(3) penetration into viable epidermis when compared with each treatment. Our ultrastructural findings show the synergistic effect of LFS and TS or OA application on transdermal drug delivery. We also found that this combined treatment enhances the penetration of LaNO(3) through the viable epidermis through an intracellular pathway.

Clinical profile of Chikungunya in infants.

OBJECTIVE: To define the clinical manifestations of Chikungunya infection in infants. METHODS: The inclusion criteria was fever (defined as axillary temperature > 99.6 degrees F) with any one of the following features; seizure, loose stools, peripheral cyanosis, skin manifestations or pedal edema in children less than one year. Details of disease from onset of illness till admission were noted and a thorough clinical examination was done at the time of admission. Daily follow-up was performed and the serial order of appearance of clinical features was noted till complete recovery. The sera collected from patients after the 7th day of onset of fever was analyzed for specific chikungunya antibody by IgM antibody capture enzyme linked immunosorbent assay (ELISA). RESULTS: Fifty six (56) infants were laboratory confirmed for chikungunya, consisting of 34 (60.71%) males and 22 (39.29%) females. 4 (7.14%) infants were less than 1 month of age, 39 (69.64%) 2-6 months old and 13 (23.21%) 7-12 months old. Fever was invariably present, but associated constitutional symptoms in infants consisted of lethargy or irritability and excessive cry. The most characteristic feature of the infection in infants was acrocyanosis and symmetrical superficial vesicobullous lesions were noted in most infants. Erythematous asymmetrical macules and patches were observed which later progressed to morbiliform rashes. The face and oral cavity was spared in all observed patients. CONCLUSION: An entirely different spectrum of disease is seen in infants with chikungunya as compared to older children who need to be carefully observed for. The morbidity and mortality of the disease may be avoided by the rational use of drugs and close monitoring of all infants.