A minimally invasive novel design for a vascular-pedicled bone segment for experimental studies of reconstruction of mandibular defects

We describe a new minimally invasive vascularised bone segment (VBS) for experimental reconstruction of the mandible. The study was validated and the feasibility was tested on fresh sheep cadavers. The integrity of the arterial blood supply was confirmed using inferior dental artery static arteriography. A pilot investigation was conducted on two adult sheep. Two full thickness bone cuts 35 mm apart were created in the parasymphyseal region. The inferior dental neurovascular bundle was preserved at the posterior bone cut but not anteriorly. A VBS was created, pedicled only on the inferior dental artery. The continuity of the mandible was maintained using fixation plates and the animals were followed up for 12 weeks. There was complete bony union and restoration of approximately 80% of the bony strength. The model is minimally invasive, reduces the operating time, and does not require special equipment and skills in microvascular anastomosis.     

Effects of oat beta-glucan on innate immunity and infection after exercise stress

PURPOSE: To test the effects of oat beta-glucan (ObetaG) on respiratory infection, macrophage antiviral resistance, and NK cytotoxicity. METHODS: Mice were randomly assigned to one of four groups: Ex-H2O, Ex-ObetaG, Con-H2O, or Con-ObetaG. ObetaG was fed in the drinking water for 10 d before intranasal inoculation of HSV-1 or sacrifice. Exercise consisted of treadmill running to volitional fatigue (approximately 140 min) for three consecutive days. Fifteen minutes after the last bout of exercise or rest, mice (N = 24) were intranasally inoculated with a standardized dose of HSV-1. Mice were monitored twice daily for morbidity and mortality. Additional mice were sacrificed after exercise, peritoneal macrophages were obtained via i.p. lavage and assayed for antiviral resistance to HSV-1 (N = 18), and spleens were harvested and assayed for NK cell cytotoxicity (N = 12). RESULTS: Exercise stress was associated with a 28% increase in morbidity (P = 0.036) and 18% increase in mortality (P = 0.15). Ingestion of ObetaG before infection prevented this increase in morbidity (P = 0.048) and mortality (P = 0.05). Exercise stress was associated with a decrease in macrophage antiviral resistance (P = 0.007), which was blocked by ingestion of ObetaG (P < 0.001). There were no effects of exercise or ObetaG on NK cytotoxicity. CONCLUSION: These data suggest that daily ingestion of ObetaG may offset the increased risk of URTI associated with exercise stress, which may be mediated, at least in part, by an increase in macrophage antiviral resistance.     

Imprint cytology of needle core-biopsy specimens of breast lesion: is it best of both worlds?

The concept and working of one-stop breast clinic has been evolving over the last 10 years. With more frequent use of core biopsy by the dedicated breast units, one-stop results service cannot be provided. The purpose of this study was to examine the feasibility of the use of imprint cytology of the core-biopsy specimens of breast lesions in a one-stop setting, in order to spare patients pain and suffering of a needle test without anaesthetic while retaining the advantages of availability of greater pathological characteristics of tumours by core biopsy. Forty-one consecutive core-biopsy specimens from symptomatic patients who underwent free hand or ultrasound-guided core biopsies of the suspected breast lesion were rolled on a glass slide to obtain imprint cytology. The cytological reporting was done independent of histological reporting of core biopsy. Overall concordance between imprint cytology and histology was 90%. For imprint cytology overall sensitivity was 91% and specificity was 89%. The positive predictive value was 97% and negative predictive value was 73%. Imprint cytology was found to be a quick, reliable and effective way of diagnosing breast lesions in breast clinic.     

Occurrence of low birthweight and preterm delivery among California infants before and after compulsory food fortification with folic acid

OBJECTIVES: Studies suggest that folic acid intake influences the occurrence of low birthweight and preterm delivery. Since 1998, there has been compulsory fortification of flour and other grains with folic acid in the U.S. The objective of this study was to investigate the frequencies of low birthweight and preterm delivery after mandatory folic acid fortification among approximately six million California births. METHODS: The authors investigated prevalences of low birthweight and preterm delivery before and after compulsory fortification among 5,916,630 singleton California live births that occurred from January 1990 through December 2000. RESULTS: The unadjusted prevalences of very low birthweight, low birthweight, and preterm delivery did not substantially vary across birth years. That is, substantial decreased prevalences during the fortification period relative to the period preceding it were not observed. However, analyses that simultaneously adjusted for maternal age, parity, race/ethnicity, education, year of birth, and fortification period revealed the following relative risk ratios (RR) and 95% confidence intervals (CI): RR = 0.91, CI 0.88, 0.94 for very low birthweight, RR = 0.94; 95% CI 0.93, 0.96 for low birthweight, and RR = 0.96; 95% CI 0.94, 0.97 for preterm delivery. CONCLUSION: Findings indicate small reductions in prevalences of these outcomes associated with the timing of fortification of the U.S. food supply.     

Different levels of polybrominated diphenyl ethers (PBDEs) and chlorinated compounds in breast milk from two U.K. Regions

Polybrominated diphenyl ether (PBDE) congeners are constituents of flame retardants, and there is growing concern regarding their persistence, bioaccumulation, and toxicity. We collected breast milk samples between late 2001 and early 2003 from 54 U.K.-resident mothers. Of these, 27 originated from southeast England (London), and the other 27 originated from northwest England (Lancaster). Analysis of milk-fat extracts by gas chromatography-mass spectrometry was performed to determine the levels of 15 PBDE congeners, 15 polychlorinated biphenyl (PCB) congeners, and other selected chlorinated compounds. PCB and organochlorine (OC) levels in southeast samples were consistently higher, and significant differences (p < 0.05) were observed. Sigma PBDE levels ranged from 0.3 to 69 ng/g lipid (geometric mean, 6.6 ng/g), and PBDE-47 was the most abundant congener. Sigma PCB levels ranged from 26 to 530 ng/g lipid (geometric mean, 150 ng/g) and were composed mainly of PCB-153 (26%), PCB-138 (20%), and PCB-180 (13%). OC levels for 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDT) and its metabolites (Sigma DDX) ranged from 24 to 2,300 ng/g lipid (geometric mean, 160 ng/g);Sigma hexachlorocyclohexane levels ranged from 1.2 to 1,500 ng/g lipid (geometric mean, 16 ng/g). Using nuclear magnetic resonance-based metabonomics, samples (n = 7) containing the highest contaminant levels were compared with samples (n = 7) containing the lowest levels. Excellent separation along the first principal component implied that the chemical constituents of the two groups were significantly different. Although reasons for such differences remain obscure, lifestyle factors associated with a more heterogeneous London cohort could be responsible. Identifying primary routes of contaminant exposures and their biologic effects is of great importance. Key words: breast milk, flame retardants, gas chromatography-mass spectrometry, milk-fat extracts, organochlorines, PBDE-47, persistent contaminants, polybrominated diphenyl ethers, polychlorinated biphenyls, United Kingdom.     

Anti angiogenesis

Based on presentations on the basic concepts and scientific rationale of anti-angiogenic approaches to cancer therapy and the possible applications in the area of prostate cancer, gastrointestinal cancer, lung cancer and breast cancer it is easy to conclude that development of anti-angiogenic approaches into clinical therapies is extremely challenging. It is now well established that cancer growth is increased by angiogenic factors and that inhibition of angiogenesis decreases growth and metastatic potential. Anti-angiogenic effect can be obtained through interference with multiple targets. Further development of new strategies involving such novel cancer therapies requires wide reaching development of translational research abilities. However, for moving new therapies into the clinic same rigorous criteria need to be applied as is done for traditional therapies. Angiogenesis appear to be a critical factor for development of prostate, gastric, lung and breast cancers. Development of new anti-angiogenic treatment modalities might become very important in these diseases. A critical requirement for the successful clinical development will be the development of imaging techniques that can help evaluate the effect on blood vessel functionality. Such surrogate markers of anti-angiogenic effect will be essential for optimising molecules and doses.     

Percutaneous penetration and genotoxicity of 4,4'-methylenedianiline through rat and human skin in vitro

4,4'-Methylenedianiline (MDA) is a primary aromatic amine used in the plastics industry and is classified by the International Agency for Research on Cancer as an animal carcinogen and possible human carcinogen. In order to estimate human exposure it is useful to determine percutaneous penetration. Previous studies have suggested that both rat and human skin were permeable to MDA, with greater penetration being seen through human skin. In this study no significant difference was seen between the percutaneous penetration of MDA through human or rat skin for three different treatment levels: 0.01, 0.1 and 1mg per skin membrane (0.32 cm(2)). The apparent dermal flux was calculated as 0.7 +/- 0.3 and 10.1 +/- 2.0 microg/cm(2)/h for the 0.01 and 0.1mg treatments, respectively. The permeability constant K(p) was estimated at 1.8 x 10(-3) cm/h and the lag time at 3.5 +/- 0.5 h. MDA absorbed into the skin was found to be bioavailable. Experiments also showed that after application of 0.1mg MDA, 4% penetrated through latex and nitrile gloves, respectively. The potential genotoxicity of MDA in human skin was assessed by DNA (32)P-postlabelling; levels of DNA adducts were detected, following the treatment and penetration of 1mg MDA.     

A prospective association between cocoon use in infancy and childhood asthma

There is increasing evidence for a role for bedding items in the development of asthma. The use of some forms of synthetic bedding, such as foam mattresses and pillows, is associated with a significantly increased risk of childhood wheeze. Our aim was to examine prospectively whether the use of synthetic cocoon/baby nests in infancy is associated with the subsequent development of wheeze in childhood. Data collected in 1988 as part of the Tasmanian Infant Health Survey were linked to the cross-sectional Childhood Asthma Survey conducted in 1995 in Tasmania, Australia. We were able to match 863 records out of the 1111 in the 1988 survey. Information including parental, child-care, and the infant's sleeping environment was collected at home interview in 1988 when the infant was 1 month of age. Data including sleep environment and asthma symptoms were available for each child at age 7 years. A generalised linear model was used to calculate the adjusted relative risk (RR) estimates for symptoms of wheeze and infant cocoon use. For children who were placed in a cocoon in infancy, there was an increased risk of recent wheeze (adjusted RR = 4.33 [95% CI 2.08, 9.02]) and night wheeze (adjusted RR = 3.35 [95% CI 1.52, 7.39]) at age 7 years. In view of the increasing prevalence of childhood asthma, the identification of potentially modifiable environmental factors which might operate in infancy is of importance. The present findings implicate infant bedding choice as a significant factor and further studies on the infant sleeping environment are indicated.     

Food fortification with folic acid and twinning among California infants

This study sought to determine whether a change in twinning prevalence was associated with mandatory folic acid fortification. As of January 1998, it became mandatory in the United States that grain products be fortified with folic acid. The effectiveness of this fortification for neural tube defects has been explored, but other possible implications of fortification has not. We computed the prevalence of twinning among more than 2.5 million California births occurring from 1990 to 1999. The prevalence of twin births in California increased over the last decade with increases observed among most maternal race/ethnic, age, and parity groupings. Unadjusted prevalence measures did not reveal substantial increases in twinning prevalence among these groupings after the fortification period relative to the period immediately preceding it. Analyses that simultaneously adjusted for age, parity, race/ethnicity, sexes of twin pair (as a measure of zygosity), year of birth, and fortification period also did not reveal an association between fortification and twinning. Our results do not suggest a change in twinning prevalence associated with folic acid fortification of the US food supply among women delivering in California.