1,721,180 research outputs found
Biocompatibility of multi-wall carbon nanotubes on human neuroblastoma cell line and effects of metal impurity and surface oxidation
No full textDescriptive epidemiology of isolated anal anomalies: a survey of 4.6 million births in Europe.
No full textThe prevalence of anal anomalies among
4,618,840 births recorded in 33 EUROCAT
registries between 1980 and 1994 was 4.05
per 10,000 births. Of the 1,846 recorded
cases, 672 (36.4%) were isolated anal anomalies
while 1,174 (63.6%) occurred together
with other anomalies. Only isolated anal
anomalies were analyzed in this study:
75.5% were atresias, 10.1% of which were
above and 89.9% were below the level of the
levator ani muscle. Fistula occurred in 53%
of supralevator and 37% of infralevator
atresia. Other anal anomalies were ectopic
anus (3.4%), congenital anal ®stula (14.7%),
and persistent cloaca (0.9%). There was a
predominance of males in anal atresia without
®stula (male to female (M:F) ratio was 6.7
for supralevator and 2.3 for infralevator
atresia), but no signi®cant sex difference in
atresias with ®stula. There was a predominance
of females in ectopic anus and congenital
anal ®stula (M:F0.11 and 0.36
respectively). High frequencies of fetal
deaths were recorded in supralevator atresia
without ®stula (8.3%) and in persistent
cloaca (11.1%). Mean gestational length and
mean birth weights were reduced for persistent
cloaca but were within normal limits
for other isolated anal anomalies. Odds
ratios (ORs) for mothers above 35 years
were increased for supralevator atresia
without ®stula, supralevator atresia with
®stula, and congenital anal ®stula. ORs for
mothers below 30 years were slightly
increased for supralevator atresia without
®stula and decreased for persistent cloaca.
There were marked differences in prevalence
and distribution of anal anomalies
among the EUROCAT registries. The results
indicated that there are epidemiological
differences among the various types of anal
anomalies which might re ̄ect different
embryological origins
Science, medicine, and the future Capsule endoscopy
No full textCapsule endoscopy was unveiled at Digestive Disease Week 2000 in San Diego, California, USA, by Paul Swain, gastroenterologist at Imperial College St Mary’s Hospital, London, and Given Imaging, a Yoqneam (Israel) company, as the product of collaborative research and development activities between the two groups.1 The past few years have seen advances in this technology, which is now part of established clinical practice in North America, Europe, the Far East, and Australia, particularly for imaging the small bowel. This article describes current clinical applications of capsule endoscopy and looks at future developments
Anorectal anomalies associated with or as part of other anomalies.
No full textAnorectal anomalies occurring with other
anomalies or as part of syndromes were
analyzed to determine how their epidemiological
characteristics differed from those
of isolated anal anomalies. Almost 15% of
cases were chromosomal, monogenic or teratogenic
syndromes, whereas the rest were
of unknown cause including sequences
(9.3%), VACTERL associations (15.4%) and
multiple congenital anomalies (MCA) (60.2%).
Almost half of babies with MCA had one or
two VACTERL anomalies with distribution
frequencies that did not differ significantly
from those in babies with the full VACTERL
association. There were considerable differences
in the frequency of the VACTERL
association among babies with different
types of anorectal anomaly. Babies with
anal anomalies occurring with sequences,
VACTERL or MCA showed the same sex
differences as babies with isolated anal
anomalies, namely male predominance in
anal atresia without fistula or cloaca, no sex
difference in anal atresia with fistula, and
female predominance in ectopic anus and
congenital anal fistula. These anomalies,
however, were associated with significantly
lower mean gestational lengths and birth
weights, and higher frequencies of fetal
death and pregnancy termination than
babies with isolated anal anomalies. Twins
were more frequent in sequences, VACTERL
and MCA than in isolated anomalies, monogenic
syndromes or chromosome anomalies.
Five cases were conjoined twins, representing
15% of all cases of twin pregnancies with
an anal anomaly. Indeterminate sex was
more frequent in babies with anal atresias
without fistula than in those with fistula.
Anal anomalies are defects of blastogenesis
attributable to disorders in expression of
pattern determining genes. The differential
sex involvement in different types of anal
anomaly may be manifestations of expression
of the HY/SRY genes during blastogenesis
or of X-linkag
Synthesis, characterisation and dispersion of zinc oxide nanorods for biomedical applications
No full textNanoparticles are increasingly being recognised for their potential utility in biomedicine. Here, the authors present a low-temperature, solvo-thermal method to synthesise zinc oxide (ZnO) nanorods using ZnO nanoparticles as precursors, with the addition of low-density polyethylenimine (PEI). This surfactant, which is in regular use in biology, has a double advantage: (i) it catalyses the synthesis owing to the amino groups on its polymeric chain and (ii) it wraps around ZnO nanorods as the crystal grows. The synthesis is followed by scanning electron microscopy, energy-dispersive spectroscopy and spectrophotometric analysis. The length of nanorods was dependent on the reaction time: around 300 nm, 1 mu m and 5 mm, respectively, for 3, 6 and 12 h of reaction time. Toxicology studies showed that cellular response is both dose and size-dependent. Sub-1 mu m ZnO nanorods were found to be internalised by cells and strongly affect cell viability with a process mediated by reactive oxygen species (ROS) production. The internalisation rate of bigger nanostructures is significantly lower, resulting in a moderate cytotoxicity with no detectable ROS production.</p
OXIGEN DERIVED FREE RADICAL PRODUCTION IN THE OESOPHAGO-GASTRO-DUODENAL MUCOSA AFTER ACID AND BILE EXPOSURE: EXPERIMENTAL STUDY IN RATS
No full text
Combination of polymer technology and carbon nanotube array for the development of an effective drug delivery system at cellular level
No full textIn this article, a carbon nanotube (CNT) array-based system combined with a polymer thin film is proposed as an effective drug release device directly at cellular level. The polymeric film embedded in the CNT array is described and characterized in terms of release kinetics, while in vitro assays on PC12 cell line have been performed in order to assess the efficiency and functionality of the entrapped agent (neural growth factor, NGF). PC12 cell differentiation, following incubation on the CNT array embedding the alginate delivery film, demonstrated the effectiveness of the proposed solution. The achieved results indicate that polymeric technology could be efficiently embedded in CNT array acting as drug delivery system at cellular level. The implication of this study opens several perspectives in particular in the field of neurointerfaces, combining several functions into a single platform
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