Lower polyunsaturated fatty acid levels and FADS2 expression in adult compared to neonatal keratinocytes are associated with FADS2 promotor hypermethylation.

Keratinocytes produce lipids that are critical for the skin barrier, however, little is known about the impact of age on fatty acid (FA) biosynthesis in these cells. We have examined the relationship between keratinocyte FA composition, lipid biosynthetic gene expression, gene promoter methylation and age. Expression of elongase (ELOVL6 and 7) and desaturase (FADS1 and 2) genes was lower in adult versus neonatal keratinocytes, and was associated with lower concentrations of n-7, n-9 and n-10 polyunsaturated FA in adult cells. Consistent with these findings, transient FADS2 knockdown in neonatal keratinocytes mimicked the adult keratinocyte FA profile in neonatal cells. Interrogation of methylation levels across the FADS2 locus (53 genomic sites) revealed differential methylation of 15 sites in neonatal versus adult keratinocytes, of which three hypermethylated sites in adult keratinocytes overlapped with a SMARCA4 protein binding site in the FADS2 promoter.

Wrinkle reduction in post-menopausal women consuming a novel oral supplement: a double-blind placebo-controlled randomized study.

OBJECTIVE: The maintenance of youthful skin appearance is strongly desired by a large proportion of the world's population. The aim of the present study was therefore to evaluate the effect on skin wrinkling, of a combination of ingredients reported to influence key factors involved in skin ageing, namely inflammation, collagen synthesis and oxidative/UV stress. A supplemented drink was developed containing soy isoflavones, lycopene, vitamin C and vitamin E and given to post-menopausal women with a capsule containing fish oil. METHOD: We have performed a double-blind randomized controlled human clinical study to assess whether this cocktail of dietary ingredients can significantly improve the appearance of facial wrinkles. RESULTS: We have shown that this unique combination of micronutrients can significantly reduce the depth of facial wrinkles and that this improvement is associated with increased deposition of new collagen fibres in the dermis. CONCLUSION: This study demonstrates that consumption of a mixture of soy isoflavones, lycopene, vitamin C, vitamin E and fish oil is able to induce a clinically measureable improvement in the depth of facial wrinkles following long-term use. We have also shown, for the first time with an oral product, that the improvement is associated with increased deposition of new collagen fibres in the dermis.

An exploratory study into therapeutic alliance, defeat, entrapment and suicidality on mental health wards.

WHAT IS KNOWN ON THE SUBJECT?: The strength of a relationship between people with mental health difficulties and professionals has been linked to patients feeling suicidal. A relationship has been found between how defeated and trapped people with mental health difficulties feel and how suicidal they feel. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: This study explored the relationship between alliance, suicidality, defeat and entrapment in people admitted to mental health wards as previous research has focused on people in the community. Patient-rated defeat, entrapment and suicidality are related in this sample of people admitted to mental health wards. A relationship was found between how well nurses said they bonded with their named patient and how trapped the patients felt by their environment. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Nurses should consider if patients are feeling defeated or trapped when helping people with mental health difficulties to feel less suicidal. ABSTRACT: Introduction Suicidality is prevalent worldwide, particularly in people who access mental health services. The quality of therapeutic alliance between people with mental health difficulties and staff has been associated with suicidality but only in community settings. Defeat and entrapment are correlated with suicidality and may mediate any relationship between alliance and suicidality. Therefore, this exploratory study explored these relationships in people admitted to mental health wards. Aim To explore defeat, entrapment, suicidality and alliance between nurses and people admitted to mental health wards. Method Fifty inpatient nurse-patient dyads completed questionnaires regarding demographics, defeat, entrapment, suicidality and alliance with their named nurse. Nurses completed questionnaires on demographics, alliance with their patient and the patients' suicidality. Results Defeat, entrapment and suicidality were correlated. A correlation between nurse-rated bond and external entrapment was found, but no other correlations between alliance, defeat, entrapment and suicidality were statistically significant. Discussion and clinical implications Ward-based nurses should consider the relationship between defeat, entrapment and suicidality when developing interventions to improve suicidality. Although there was no evidence of a relationship between total alliance and suicidality, developing closer bonds with patients may reduce patients' feelings of being trapped by their environment.

Concurrent evaluation of personal damaging and beneficial UV exposures over an extended period.

Personal exposure to solar ultraviolet radiation (UVR) is acknowledged as having both positive and negative effects on human health. This study aimed to measure concurrently the personal erythemal UV, UVA and vitamin D effective exposures of participants in each season of a year. Participants were all indoor office workers located at two different sites less than 6.5 km apart at the sub-tropical location of Toowoomba (27°33'S 151°55'E). The subjects wore a combined dosimeter badge horizontally on the shoulder for a minimum of one week in each season; this badge used 8-methoxypsoralen film to record the UVA waveband and polyphenylene oxide film for the erythemal and the vitamin D effective UV wavebands. The results show that median erythemal exposure was highest during the spring and lowest during winter, as was the vitamin D effective exposure. Median UVA exposures were at a similar level in winter and summer, autumn was higher (double) and spring at a lower level. The duration and time of day participants spent outdoors changed in each season; in winter, participants spent an average of 101 minutes outdoors between 10:00-14:00 h over the week, whereas in summer this fell to 79 minutes even though they were outdoors more often. The daily UVA/UVB ratio is lowest between 10:00-14:00 h and also changes with the season resulting in the differences between the distributions of exposure for each of the wavebands. Each category of exposures must be assessed individually as each season and each waveband has different distributions. The results also demonstrate that the dual film dosimeter developed and characterized with a calibration to three different biological responses, is an effective device for the concurrent measurement of erythemal UV, UVA and vitamin D effective UV exposures for periods of up to seven days.

Germ-line and acquired mutations of INI1 in atypical teratoid and rhabdoid tumors.

We examined 18 atypical teratoid and rhabdoid tumors of the brain and 7 renal and 4 extrarenal rhabdoid tumors for mutations in the candidate rhabdoid tumor suppressor gene, INI1. Fifteen tumors had homozygous deletions of one or more exons of the INI1 gene, and the other 14 tumors demonstrated mutations. Germ-line mutations of INI1 were identified in four children, one with an atypical teratoid tumor of the brain and three with renal rhabdoid tumors. These studies suggest that INI1 is a tumor suppressor gene involved in rhabdoid tumors of the brain, kidney, and other extrarenal sites.

Dual calibrated dosimeter for simultaneous measurements of erythemal and vitamin D effective solar ultraviolet radiation.

A miniaturized ultraviolet radiation (UV) dosimeter based on polyphenylene oxide (PPO) has been dual calibrated for both erythemal and vitamin D effective exposures (UVB 280 - 320 nm) over extended periods up to five days. Optimal human health requires a balanced amount of UVB exposure as both too much and too little have different but serious potential health consequences. Dosimetry is an established method of measuring specific UV exposures to an object or subject. PPO dosimeters have previously been used to measure the erythemally effective UV exposure. An extension of this use is to dual calibrate the miniaturized dosimeter which will also enable measurement of vitamin D effective exposures. By calibration to the erythemal and vitamin D effective action spectra, PPO dosimeters were able to record both types of biologically effective exposure as both are active within the UVB waveband. Dose response tests were conducted in each season by exposure to solar UV with the corresponding dual calibrations made for each season. The calibration provided an R(2) of 0.95-0.99 for erythemal UV and an R(2) of 0.99 for vitamin D effective UV. The successful outcome of this testing has established that PPO is suitable for use as a long term, dual calibrated dosimeter provided the film is seasonally calibrated. This enables one dosimeter to provide two sets of exposure results. The combination of dual calibration and the long term exposure potential of PPO makes the PPO dosimeter more versatile and increases the scope of UV field research on erythemal UV and vitamin D effective UV in the future.

Stimulation by isoproterenol of erythropoiesis in cultures of dispersed cells of the primitive-streak chick blastodisc.

Low concentrations of isoproterenol stimulated proliferation of precursors of erythroid cells in cultures of cells prepared from the developing chick blastodisc at the stage of the primitive streak. Propranolol blocked this stimulatory action but had no effect upon erythropoiesis in the absence of isoproterenol.

Dosimeter based on 8-methoxypsoralen for UVA exposures over extended periods.

A miniaturized UVA dosimeter based on 8-methoxypsoralen (8-MOP) has been developed and characterized for the evaluation of UVA (320-400 nm) exposures over extended periods longer than one day. Current research indicates that UVA is a contributing factor in non-melanoma skin cancers and the associated financial cost of damage caused by UVA is significant. Dosimetry is a technique that is commonly employed to measure UV exposures to an object or subject. Miniaturized dosimeters using polyphenylene oxide (PPO) have previously been used to measure received erythemal UV (UVery) exposures. A new miniaturized dosimeter using 8-MOP as the photoactive material has been characterized and a technique developed for the calibration of UVA exposures. Using Mylar as a UVB filter the spectral response showed 8-MOP to react only to wavelengths between 320 and 400 nm. The measured cosine response has an error of less than 13.8% for angles between 0° and 60°. Seasonal dose response tests conducted, indicate that these UVA dosimeters are able to measure exposures <4.6 kJ/m(2). These results have shown that a dosimeter constructed from 8-MOP in conjunction with a Mylar filter can measure UVA exposures over extended periods longer than one day.

Cellular composition of erythropoietic cell populations and aggregate cell cultures derived from early chick blastodiscs.

Light and electron microscopy of suspensions of cells prepared by dispersing chick blastodiscs at primitive-streak and head-fold stages showed the presence of numerous yolk granules, yolk-rich endodermal cells and occasional presumed ecto- and mesodermal cells. Several cell fractions prepared from this suspension by sedimentation through discontinuous Ficoll gradients were of similar composition. No enrichment of any particular cell type which might account for either differential sedimentation or erythropoietic potential of the fractions could be recognized. Two fractions, EP 1, and EP 2, were cultured as cell aggregates on vitelline membranes. EP 1 produced highly organized blood islands containing developing erythrocyte cells, organized endothelium, fibroblasts, thrombocytes and occasional granulocytes. Blood islands derived from EP 2, on the other hand, contained essentially only aggregates of erythroblasts embedded in endoderm. It is tentatively suggested that EP1 contains young multipotential hematopoietic precursors while EP 2 has only older blood-cell precursors committed to erythrocyte development. No cellular basis for the resolution of EP 1 into two complementary subfractions could be recognized.

Voluntary vacation attachments to rural general practitioners: experience with pre-clinical medical students.

In view of the continuing maldistribution of medical manpower away from rural practice, a voluntary vacation rural general practitioner attachment scheme was established for pre-clinical students. The responses of the students and preceptors to these attachments are discussed.

Malignant liver tumors in South African children: a national audit.

BACKGROUND: Malignant liver tumors (mostly hepatoblastoma [HB] and hepatocellular carcinoma [HCC]) are uncommon, representing 0.5%-2% of childhood malignancies worldwide. The pattern of liver tumors appears to differ in Southern Africa as a result of infectious factors (e.g., hepatitis B/retroviral disease (HIV). This study aimed to assess recent changes in the prevalence and surgical management of liver tumors in South African children. METHODS: Data were obtained from the tumor registry and pediatric oncology units in South African hospitals to audit and review the epidemiology, treatment, and outcome of malignant hepatic tumors in South African children. RESULTS: Malignant primary hepatic tumors were reported in 274 children (ages 0-14 years) from 1988 through June 2006. Of these 134 (48%) had HB; 77 (27%) had HCC (9 [3%] fibrolamellar subtype); 38 (13%), vascular tumors; and 17 (6%), liver sarcomas. In a further 8 patients (3%) other tumors included lymphoma and endodermal sinus tumor. Vascular tumors included hemangioendotheliomas (12), and there were 5 malignant tumors in children with HIV, including 1 angiosarcoma and 13 Kaposi sarcoma-like tumors. Hepatoblastoma occurred at a mean age of 1.47 years, and none were encountered in patients > 4 years of age. Hepatocellular carcinoma mostly occurred in the older patients (mean age: 10.48 years), but 6% presented in patients < 8 years of age (10 months, 2, 2.6, 5, 5, and 6 years). Hepatic sarcoma occurred at a mean age of 7.66 years and had a female predominance (M:F ratio: 0.4). The relative HCC prevalence (male predominant: hepatitis B related) was reflected in the low HB:HCC (1.67) ratio. However, a significant decrease in HCC was attributed to the effect of hepatitis B inoculation. There appeared to be an increase in the incidence of vascular tumors, presumably the result of an increase in Kaposi-like sarcoma in retrovirus-positive patients. The surgical resection rate was low because most patients presented late, with advanced disease. Survival was 11% and 52% for HB and HCC, respectively, and was related to chemotherapeutic response and complete surgical resection. CONCLUSIONS: Liver tumors appear to have a different epidemiological pattern in South Africa. The observed increased HCC prevalence appears to be decreasing with hepatitis B vaccination. Retroviral disease does not yet appear to have a major influence on the distribution of liver tumors in South Africa, although it possibly affects the vascular tumor prevalence.

Purinergic receptors have no major role in control of the circadian rhythm in rate of thymidine incorporation by cultured chick pineal glands.

We have examined the effects of some analogues of adenosine upon the circadian rhythm in rate of thymidine incorporation by cultured chick pineal glands. Incorporation in the early period of the photoperiod on day 2 of culture was slightly inhibited by the adenosine analogue N-ethylcarboxamido-adenosine, but this effect was not countered by the antagonist 8-phenyl-theophylline. Thymidine incorporation was inhibited when glands were continuously exposed to the adenosine transport inhibitor nitrobenzyl-thioinosine, but ongoing incorporation was not inhibited by addition of this agent. Removal of adenosine and deoxyadenosine supplements from the medium, with or without further addition of adenosine deaminase, had no appreciable effects upon thymidine incorporation. We conclude that adenosine and analogues probably play no role in regulation of the rhythm in rate of thymidine incorporation.

Thymidine kinase activity of the chick pineal gland.

Pineal thymidine kinase activity of 1-week-old chicks in situ varied significantly throughout the day. However, the circadian rhythm of thymidine incorporation seen with cultured chick pineal glands was not accompanied by variations in level of thymidine kinase activity in vitro. Thus the circadian rhythm in rate of cumulative incorporation of thymidine by cultured chick pineal glands is not determined by a rhythm in rate of the first reaction of the complex series of reactions by which thymidine is incorporated into DNA.

A phase-dependent delay of the chick pineal rhythm in rate of thymidine incorporation by brief exposure to aphidicolin.

Cultured chick pineal glands show a persistent rhythm in the rate of cumulative incorporation of thymidine into DNA. In this study we have examined the effects of pulse-exposure to aphidicolin in the dark on the first day of culture on thymidine incorporation during the second and third days of culture in the dark with aphidicolin-free medium. The phase of the rhythm in the rate of thymidine incorporation was delayed in a concentration-dependent manner by a 4-hr exposure to aphidicolin, commencing in the final hour of the photoperiod. This effect was phase-dependent and not seen when exposure to aphidicolin began earlier in the photoperiod.

A phase-dependent delay of the chick pineal rhythm in rate of thymidine incorporation by brief exposure to ouabain.

Cultured chick pineal glands show a persistent rhythm in the rate of cumulative incorporation of thymidine into DNA [Wainwright and Wainwright, 1989]. In this study we have examined the effects of a pulse-exposure to ouabain in the dark on the first day of culture upon thymidine incorporation during the second and third days of culture in the dark with ouabain-free medium. The phase of the rhythm in rate of thymidine incorporation was delayed by a 4-hr exposure to 100 microM ouabain commencing in the final hour of the photoperiod, but not by a 2-hr exposure or by 10 microM ouabain. This effect was phase-dependent and not seen when exposure to ouabain began earlier in the photoperiod. The phase delay caused by ouabain was not due to a persistent direct inhibition of the process of thymidine incorporation. The phase-shift due to exposure to ouabain was superimposed on a phase delay caused by renewal of culture medium 4 hr after explanting the glands into culture.

Quality control of glycosylphosphatidylinositol anchor attachment in mammalian cells: a biochemical study.

hGHDAF28 is a chimaeric protein consisting of human growth hormone fused to a crippled signal sequence for glycosylphosphatidylinositol (GPI)-anchor addition from decay-accelerating factor, and serves as a model for quality control of GPI-anchor addition. hGHDAF28 is retained in a pre-Golgi compartment and degraded intracellularly by a mechanism with similarity to that for other endoplasmic reticulum (ER)-retained proteins (Field, Moran, Lee, Keller and Caras (1994) J. Biol. Chem. 269, 10830-10837). We have studied the specific pathway of degradation for hGHDAF28 using a number of compounds which affect protein folding and trafficking pathways in eukaryotic cells. We found that high concentrations of dithiothreitol (DTT) accelerated loss of hGHDAF28 by degradation from cell lysates, without promoting secretion or alteration of disulphide-bond distribution, in contrast to a number of other examples of ER-retained proteins where DTT alters disulphide-bond formation. Additionally, degradation of hGHDAF28 was sensitive to pH, being promoted at pH 6.0 and inhibited at pH 8.0; however, the latter effect was transient, indicating incomplete blockade. Degradation was also partially enhanced by depletion of ER calcium with thapsigargin, but this was again a partial and transient effect. Furthermore, degradation was temperature sensitive, with a gradual decrease in rate observed at lower temperatures. However, a sharp decrease in turnover between 15 degrees C and 20 degrees C, indicative of a requirement for transport to a post-ER compartment, was not observed. Degradation of hGHDAF28 was insensitive to treatment with nocodozole or compounds preventing cytoplasmic autophagy, suggesting that ER degradation is independent of classical autophagy and microtubule-dependent processes. In addition, disruption of N-glycosylation with tunicamycin, or inhibition of processing of immature N-glycan chains with castanospermine or deoxynojirimycin, had little effect on the stability of hGHDAF28, suggesting that disruption of the BiP/calnexin quality-control system by bulk cellular secretory proteins does not influence the ER-degradation pathway of hGHDAF28. Intermolecular hGHDAF28 cysteine bonds result in the formation of aggregates which are probably important in the retention of the molecule. The insensitivity of this structure to reduction in vivo, together with the enhanced degradation rate, indicates that DTT mediates its effect on stability via a molecule involved in degradation of hGHDAF28, possibly a thiol-sensitive protease.

Molecular cloning of eukaryotic glycoprotein and glycolipid glycosyltransferases: a survey.

The rapidity with which molecular sequence data are gathered continues to grow. The result is that, for many workers, it is increasingly difficult to keep abreast of the current state of play of molecular cloning, even for those genes that encode proteins of special interest. The clear success of the various worldwide genome projects has made this even more apparent, and by the end of 1996 the complete determination of the nucleotide sequences of the genomes of two eukaryotes, Saccharomyces cerevisiae and Caenorhabditis elegans, will have either been completed or will be nearing completion. This article is an attempt to provide, in an easily accessible format, a compilation of genes and cDNAs that have been sequenced and deposited in GenBank that encode transferase enzymes involved in eukaryotic glycoprotein or glycolipid biosynthesis. The full sequence information can be easily retrieved from a databank, e.g. GenBank, using the relevant accession number(s).

Relationship between cycles in level of serotonin N-acetyltransferase activity and cyclic GMP content of cultured chick pineal glands.

We examined effects of supplements on cycles in cyclic GMP content and serotonin N-acetyltransferase (NAT) activity in cultured chick pineal glands. Increases in cyclic GMP content and NAT activity were stimulated by 1-ethyl-4(isopropylidene-hydrazino)-1H-pyrazolo[3,4-b]pyridene-5-c arboxylic acid, ethyl ester, hydrochloride and isobutylmethyl xanthine under diurnal illumination and in constant darkness, but subsequent decreases were not inhibited. Hypoxanthine had little effect on NAT activity under all lighting conditions, or on the content of cyclic GMP in glands cultured in the dark. However, it markedly stimulated accumulation of cyclic GMP in illuminated cultures. EGTA or additional Ca2+ had no effect on pineal NAT activity. However, EGTA markedly stimulated accumulation of cyclic GMP both in the light and in the dark. Supplementary Ca2+ slightly retarded accumulation of cyclic GMP in the dark but stimulated slightly in the light.

Regulation of the cycle in chick pineal serotonin N-acetyltransferase activity in vitro by light.

The diurnal cycle in vivo in the level of serotonin N-acetyltransferase (NAT) activity found in the pineal gland of chicks kept under diurnal lighting was reproduced in vitro with glands incubated in organ culture under the same diurnal lighting conditions. We have examined the effects of varying the lighting conditions of culture upon development of NAT activity in vitro with pineal glands from birds which were killed at different times during the photoperiod in vivo. The ability of chick pineal glands to develop increased NAT activity in culture during the dark period of a diurnal cycle of illumination was determined primarily by the proportion of the photoperiod in vivo elapsed at the time of sacrifice of the birds. The time of development of maximal NAT activity in cultured chick pineal glands could be advanced or delayed by corresponding changes in time of start of the dark period. However, the 'settings' of the pineal 'biological clock' remained unchanged. Glands from birds sacrificed in the final 30 min of the photoperiod in vivo developed increased NAT activity without lag when cultured in the light. Similarly, pineal glands cultured under continuous illumination developed an increased photostable NAT activity beginning at the time of the "subjective" end of the photoperiod in vitro. Ability to develop additional NAT activity in the dark was low rapidly at the "subjective" time in vitro of start of the next photoperoid. The maximal NAT activity developed in the dark consisted of both photolabile and photostable components.