Nanotechnology in Dentistry Today

A review was done of nanotechnology as it applies to dentistry today. Information was gathered fro literature search, research data and material inserts in products. Nanotechnology deals with th physical, chemical and biological properties of structures and their components at nanoscale dime sions. One of the biggest contributions to restorative and aesthetic dentistry has been nanocomposite These composites are characterized by filler-particle sizes ≤ 100 nm and offer aesthetic and streng advantages over the current microfilled and hybrid resin-based composites. Nanoparticles for coatin implant surfaces and the nanopatterning of dental implants are leading to better osseointegration an improved physiologic functions of implants, while nanophase hydroxyapatite has improved i adaptation into bone graft sites. Nano-biochips are now making oral cancer screening and diagnos of diseases by saliva easier and more affordable.     

Predictors of maternal mortality in institutional deliveries in Nigeria

Background

Maternal mortality in poor countries reflects the under-development in these societies. Global recognition of the burden of maternal mortality and the urgency for a reversal of the trend underpin the Millenium Development Goals (MDGs).

Objective

To determine risk factors for maternal mortality in institutional births in Nigeria.

Method

Twenty one health facilities in three states were selected using stratified multi-stage cluster sampling strategy. Information on all delivered mothers and their newborn infants within a three-month period was culled from medical records.

Results

A total of 9 208 deliveries were recorded. About one-fifth (20.5%) of women had no antenatal care while 79.5% had at least one antenatal visit during pregnancy. Four-fifths (80.5%) of all deliveries were normal deliveries. Elective and emergency caesarean section rates were 3.1% and 11.5% respectively. There were 79 maternal deaths and 8 526 live births, giving a maternal mortality ratio of 927 maternal deaths per 100 000 live births. No antenatal care, parity, level of education, and mode of delivery were significantly associated with maternal mortality. Low maternal education, high parity, emergency caesarean delivery, and high risk patients risk independently predicted maternal mortality.

Conclusion

Meeting goal five of the MDGs remains a major challenge in Nigeria. Multi-sectoral approaches and focused political will are needed to revert the high maternal mortality.     

Effect of <Emphasis Type="Italic">Citrullus vulgaris</Emphasis> on some functional indices of selected tissues of Wistar rats

Citrullus vulgaris (watermelon) is a fruit with prophylactic and therapeutic potentials. In an attempt to maximize these potentials, the seed and rind are now often consumed together with the pulp. This study aimed at evaluating the implications of such consumption. Study involved the use of 35 Wistar rats grouped into seven with a control group administered distilled water, and the other groups administered varying concentrations of the pulp and whole fruit for 28 days. Alanine and aspartate aminotransferase (ALT, AST) were assayed in the serum and liver. Total protein of the serum and selected tissues was determined and malondialdehyde (MDA) level measured. Phytochemical screening revealed the presence of steroids, saponin, alkaloids, flavonoids, and terpenoids in both whole fruit and pulp. Significant increases (p < 0.05) were seen in the liver ALT levels while there was a decreased (p < 0.05) intestinal total protein in the treatment groups. No significant (p ? 0.05) difference was seen in the serum and pancreas MDA levels while an increased (p < 0.05) intestinal MDA level was observed. Increased liver ALT levels in all the treatment groups might be due to high glutamate levels of C. vulgaris. Decreased (p ? 0.05) intestinal total protein might be indicative of protein loss, while elevated (p < 0.05) intestinal MDA levels in the groups administered whole fruit is suggestive of a defect in absorption at the intestinal epithelium. Hence, whole fruit consumption of C. vulgaris should be done with caution as it has potential to cause intestinal oxidative stress.     

Maternal plasma level of antimicrobial peptide LL37 is a major determinant factor of neonatal plasma LL37 level

Aim: To determine cathelicidin antimicrobial peptide LL37subcellular distribution in cord neutrophils and normal plasma LL37 levels in mothers and neonates, relate them to delivery mode and relevant biochemical markers, including 25‐OHvitamin D [25(OH)D] as this molecules increases cathelicidin gene expression. Methods: A total of 115 infants were included, n = 68 with normal delivery and n = 47 with elective Caesarean section (C‐section), a subset of these being 50 mother–infant pairs. Biomarkers were determined in maternal and cord blood. Subcellular peptide LL37 distribution was analysed with immunoelectron microscopy. Results: Cord plasma LL37 levels were three‐times higher after normal delivery compared with C‐section. A highly significant correlation was observed between maternal and cord plasma LL37 levels, regardless of delivery mode. No relationship was found between LL37 and 25(OH)D levels. Neutrophils from cord blood after normal delivery contained 10‐times more cytoplasmatic cathelicidin peptide compared with corresponding cells after C‐section where a strict granular localization was found. Conclusion: These data are consistent with a placental transfer of LL37 and identifies maternal stores as the critical factor determining neonatal plasma LL37 level. An additional enhancement of neonatal cathelicidin mobilization and release is connected to normal delivery stress.     

Skin bleaching: highlighting the misuse of cutaneous depigmenting agents

Hydroquinone and other cutaneous depigmenting agents are widely used by dermatologists to treat pigmentary disorders. On 29 August 2006, the US Food and Drug Administration (FDA) published a monograph in the US Federal Register proposing to ban all hydroquinone products that have not been approved via a New Drug Application process. Reports in the scientific literature on the occurrence of exogenous ochronosis, in relation to the use of hydroquinone, was one of the concerns expressed by the FDA in relation to this agent. However, a review of the English-language scientific literature reveals that most of the reported cases of hydroquinone-induced exogenous ochronosis occurs in Africa, where the cultural practice of skin bleaching is highly prevalent. Skin bleaching is the practice of applying hydroquinone and/or other depigmenting agents to specific or widespread areas of the body, the primary function being to lighten normally dark skin. This practice typically occurs in men and women with Fitzpatrick skin phototypes IV to VI. It is a dangerous practice associated with a diverse range of side-effects, including mercury poisoning. Thus, this current discussion within the dermatological community on the safety of hydroquinone provides a unique opportunity to raise awareness about skin bleaching.     

Willingness to pay for the maintenance of equity in a local ivermectin distribution scheme in Toro, Northern Nigeria

The willingness to pay (WTP) for the maintenance of equity in a local ivermectin distribution scheme in the context of a community financing framework was determined in Toro, Northern Nigeria, using 214 randomly selected heads of households, or their representatives. Though WTP of the respondents for their own households was elicited, the focus of this paper is on WTP to maintain equity in a community financing scheme. Contingent valuation was used for the exercise, and WTP was elicited using an open-ended question. 97.2% of the respondents were in favour of allowing those that lack the ability to pay, to benefit from the scheme and the maximum WTP amounts they were willing to contribute annually so that those who lack the ability to pay could benefit from the scheme ranged from 5 Naira ($0. 06) to 100 Naira ($1.25). The mean WTP to maintain equity was 29.00 Naira ($0.36) while the median was 20.00 Naira ($0.25). This study shows that a community financing scheme for local ivermectin distribution will not be inequitable, since enough funds will be realised from well-to-do community members to cover the costs for those who are unable to pay.     

Saline cathartics and adsorptive capacity of activated charcoal for doxycycline

The effects of sodium chloride and sodium citrate on the in vitro adsorption of doxycycline to activated charcoal have been studied. Solutions of doxycycline alone and doxycycline with 7.5 mg/ml cathartic solutions were vortex-mixed for 30 s with different quantities of activated charcoal, incubated for 30 min at 37 degrees C and analyzed for free doxycycline spectrophotometrically at 348 nm. Addition of NaCl had a significant (p<0.05) increase while sodium citrate produced a significant (p<0.05) decrease in the adsorption of doxycycline on activated charcoal. In all, the adsorption doxycycline on activated charcoal obeyed quantity-dependent kinetics.     

Effects of rinbacin extract on rat kidney

The aqueous leaf extract of rinbacin was tested for toxic effects on prepubertal rat kidneys following chronic administration. Two doses of rinbacin extract (26.25 g/l and 52.50 g/l) were administered in the rats' drinking water for 13 weeks, and various toxicologic indices tested. Histological study of the kidneys was also carried out at the expiration of the test period. Rinbacin at both dose sizes significantly (p<0.05) increased the absolute and relative kidney weights. Also the serum HCO3- level was significantly (p<0.05) increased, while the serum K+ level was decreased significantly at both dose levels. Only the high dose significantly (p<0.05) increased the serum urea level of the rats. Histological study showed that rinbacin at both dose sizes caused renal pathologic changes, which included necrosis and cellular infiltration of glomeruli and epithelia of the tubules. The effects were less marked in the low dose than the high dose group. Chronic administration of rinbacin extract induces nephrotoxicity in young rats.     

Nephrotoxic actions of low-dose mercury in mice: protection by zinc

The authors conducted this study to determine if very-low-dose (i.e., 4 ppm) mercury is nephrotoxic and, if so, whether the nephrotoxic actions of mercury in mice could be prevented by zinc intake. Animals were administered 4 ppm mercuric chloride and/or 800 ppm zinc chloride in their drinking water for 12 wk. The animals were sacrificed at the end of the exposure period, and their kidneys were excised, weighed, and processed for histological study. Both metals reduced significantly (p < .05) the absolute and relative kidney weights of the animals. Zinc-treated animals showed normal kidney histology that was comparable with that of the control. Mercury treatment produced necrosis and widening of the glomeruli, whereas a combination of both metals resulted in protection from the toxic effects, with most nephrons resembling the control. The results indicate that low-dose mercury exposure in mice kidney induces some degenerative effects, which are prevented by zinc.     

Testicular toxicity of Nigerian bonny light crude oil in male albino rats

The purpose of this work was to investigate the testicular effects of Nigerian bonny light crude oil on male albino rats. Male albino rats were administered 200, 400, and 800 mg/kg body weight of bonny light crude oil dissolved in Tween 80 in their drinking water for 7 days, while the control group received Tween 80 in their drinking water only. After 7 days, the rats were sacrificed and testis excised, weighed, and processed for histological examination. Treatment with bonny light crude oil showed a dose-dependent decrease in the absolute weight of the testes, and a significant (P < 0.05) dose-dependent reduction in the epididymal sperm number (ESN). The final body weights of the animals treated with crude oil were also significantly (P < 0.05) decreased. Histological evaluation of the testes showed slight to severe degeneration or even complete absence of seminiferous tubules and necrosis of cells depending on the dose of the crude oil. This study suggests that the Nigerian bonny light crude oil is a testicular toxicant and its use as a folklore medicine may cause infertility.