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41.
Cristina L. Zavaleta Bryan R. Smith Ian Walton William Doering Glenn Davis Borzoyeh Shojaei Michael J. Natan Sanjiv S. Gambhir 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(32):13511-13516
Raman spectroscopy is a newly developed, noninvasive preclinical imaging technique that offers picomolar sensitivity and multiplexing capabilities to the field of molecular imaging. In this study, we demonstrate the ability of Raman spectroscopy to separate the spectral fingerprints of up to 10 different types of surface enhanced Raman scattering (SERS) nanoparticles in a living mouse after s.c. injection. Based on these spectral results, we simultaneously injected the five most intense and spectrally unique SERS nanoparticles i.v. to image their natural accumulation in the liver. All five types of SERS nanoparticles were successfully identified and spectrally separated using our optimized noninvasive Raman imaging system. In addition, we were able to linearly correlate Raman signal with SERS concentration after injecting four spectrally unique SERS nanoparticles either s.c. (R2 = 0.998) or i.v. (R2 = 0.992). These results show great potential for multiplexed imaging in living subjects in cases in which several targeted SERS probes could offer better detection of multiple biomarkers associated with a specific disease. 相似文献
42.
Lund SS Tamow L Stehouwer CD 《药品评价》2008,5(8):380-380
在2型糖尿病患者中,反映炎症和内皮功能障碍的生物标志已经与心血管疾病和代谢调节联系起来。二甲双胍和促胰岛素分泌剂被证明有相同的抗高血糖作用。此研究比较了二甲双胍和促胰岛素分泌剂瑞格列奈在非肥胖的2型糖尿病患者的心血管疾病生物标志上的效能。 相似文献
43.
DC Wilson MJ Cunningham MMcC Reid SS Johnston TF Fannin 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(1):84-85
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis. 相似文献
44.
Evidence for endogenous formation of tobacco-specific nitrosamines in rats treated with tobacco alkaloids and sodium nitrite 总被引:2,自引:0,他引:2
Carcinogenic tobacco-specific nitrosamines are present in tobacco products
and are believed to play a significant role in human cancers associated
with tobacco use. Additional amounts of tobacco-specific nitrosamines could
be formed endogenously. We tested this hypothesis by treating rats with
nicotine and sodium nitrite and analyzing their urine. Initially, we
treated groups of rats with (S)-nicotine (60 micromol/kg) and NaNO2 (180
micromol/kg), (S)-nicotine alone, NaNO2 alone or
4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 12 nmol/kg) by gavage
twice daily for 4 days. We collected urine and analyzed for two metabolites
of NNK; 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanol and its glucuronide.
We did not detect these metabolites in the urine of rats treated with
nicotine alone or nicotine plus NaNO2, indicating that endogenous
conversion of nicotine to NNK did not occur. However, the urine did contain
N'- nitrosonornicotine (NNN), N'-nitrosoanabasine (NAB) and N'-
nitrosoanatabine (NAT). Analysis of the (S)-nicotine used in this
experiment demonstrated that it contained trace amounts of nornicotine,
anabasine and anatabine. In a second experiment, we used an identical
protocol to compare the endogenous nitrosation of this (S)-nicotine with
that of synthetic (R,S)-nicotine, which did not contain detectable amounts
of nornicotine, anabasine or anatabine. NNN (0.53 x 10(-3)% of nicotine
dose), NAB (0.68%) and NAT (2.1%) were detected in the urine of the rats
treated with the (S)-nicotine and NaNO2. NNN (0.47 x 10(- 3)% of dose), but
not NAB or NAT, was present in the urine of the rats treated with synthetic
(R,S)-nicotine and NaNO2. NNN probably formed via nitrosation of
metabolically formed nornicotine. These results demonstrate for the first
time that endogenous formation of tobacco- specific nitrosamines occurs in
rats treated with tobacco alkaloids and NaNO2. The potential significance
of the results with respect to nitrosamine formation in people who use
tobacco products or nicotine replacement therapy is discussed.
相似文献
45.
Expression of differential nitric oxide synthase isoforms in human normal gastric mucosa and gastric cancer tissue 总被引:10,自引:2,他引:10
The present study investigated the expression and distribution of three
isoforms of nitric oxide synthase (NOS) in different anatomical regions of
the human stomach and in gastric neoplastic tissues by immunohistochemistry
using specific antibodies. Intracellular localization of individual
isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer
tissues had a marked reduction of all three NOS isoforms expression. The
expression of the endothelial NOS, neuronal NOS and inducible NOS in the
tumor tissue was significantly lower than in normal gastric mucosa (P =
0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the
expression of inducible NOS was significantly lower than the expression of
both constitutive forms of NOS (P < 0.01). There was a tendency to
higher expression of both constitutive forms of NOS in earlier stages T2 of
the tumor compared to advanced T4 tumor. In contrast, the expression of
inducible NOS was higher than in the advanced T4 tumor than in the earlier
stages T2 of the tumor. The mapping of the expression of endothelial NOS,
neuronal NOS and inducible NOS in human stomach showed higher expression of
NOS isoforms in the distal third than in the proximal third of the stomach
(P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is
greater expression of NOS in the stomach corpus and in antrum than in the
proximal third of the normal human stomach mirroring the anatomical
predilection of common pathological changes in this part of the human
stomach. Furthermore, there was loss of the expression of individual
isoenzymes in gastric neoplasms.
相似文献
46.
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important
metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-
(3-pyridyl)-1-butanone (NNK). Using the chiral derivatizing agent, (R)-
(+)-alpha-methylbenzyl isocyanate [(R)-(+)-MBIC], previous work has shown
that the enantiomeric ratio of metabolically formed NNAL and its
glucuronide derivative may be species dependent. However, the absolute
configuration of such NNAL has not been previously reported. Synthetically
prepared racemic NNAL was converted to diastereomeric esters by reaction
with (R)-(+)- and (S)-(-)-alpha-methoxy-alpha-
(trifluoromethyl)phenylacetic acid (MTPA) chloride (Mosher's reagent) and
the products were characterized by 1H-NMR. Based on chemical shift data,
the absolute configuration of NNAL in each diastereomeric ester was
assigned. Hydrolysis of (R)-NNAL-(R)-MTPA gave (R)-NNAL. This was converted
to the corresponding carbamate by reaction with (R)-(+)-alpha- MBIC and the
absolute configurations of the diastereomeric carbamates formed by reaction
of (R)- and (S)-NNAL with (R)-(+)-MBIC were thereby assigned. Conversion of
metabolically produced NNAL to the same carbamates allowed us to assign the
NNAL formed from NNK by rat liver microsomes as (R)-NNAL. The major and
minor NNAL-glucuronide diastereomers found in the urine of patas monkeys
and humans exposed to NNK were similarly assigned; they were formed from
(R)-NNAL and (S)- NNAL, respectively.
相似文献
47.
48.
49.
Godbole KG Gambhir PS Deshpande AS Kurlekar SU Phadke MA 《Indian journal of pediatrics》1999,66(2):290-293
Research has shown that anticonvulsants are teratogens and pose a risk for fetal malformations. Though Fetal Hydantoin Syndrome
(FHS) was first reported by Langhman and others, wide phenotypic variability of this syndrome has lead many clinicians to
question its very existence. We report a twelve year old girl with FHS with rheumatic valvular heart disease. 相似文献
50.
Gambhir IS Mehta M Singh DS Khanna HD 《The Journal of the Association of Physicians of India》1999,47(2):192-194
Sixty patients of inflammatory brain disease were diagnosed and classified according to clinico-investigational criteria by Ahuja et al into tuberculous meningitis group (36 patients) and non-tuberculous meningitis group (24 patients). Tuberculous meningitis (TBM) patients were classified as probable (9 patients) and possible (27 patients) TBM. Non-TBM group comprised of pyogenic meningitis (8.3%), viral encephalitis (23.3%), cerebral malaria (5%) and enteric encephalopathy (3.3%). Cerebrospinal fluid-adenosine deaminase (CSF-ADA) activities were measured in both TBM and non-TBM groups. Mean CSF-ADA levels in TBM patients was 9.61 +/- 4.10 IU/L and was significantly elevated as compared to viral encephalitis and enteric encephalopathy cases; but difference was insignificant in comparison to pyogenic meningitis (7.92 +/- 0.95 IU/L) and cerebral malaria. Using 8 IU/L as cut off value for diagnosis of TBM a sensitivity of 44% and specificity of 75% was observed. 相似文献