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51.
Christina Vogt?IsaksenEmail author Rigmor?Austgulen Lisa?Chedwick Pal?Romundstad Lars?Vatten Catherine?Craven? 《Pediatric and developmental pathology》2004,7(5):433-442
Pregnant
women who smoke are at greater risk of delivering a growth-restricted infant
than nonsmoking mothers. We wanted to see if apoptosis could be involved in the
mechanisms behind smoke-induced growth restriction, and our aim was to compare
apoptosis in the placenta of smoking mothers giving birth to growth-restricted
infants and nonsmoking mothers with infants of appropriate weight. The project
was conducted at the Magee—Womens Hospital and Magee—Womens
Research Institute, University of Pittsburgh, PA. Histological sections from 20
placentas were selected from smoking mothers who had given birth to
small-for-gestational-age infants (birth weight 2 SD). The controls
were gestational-age matched nonsmoking mothers with infants having
appropriate-for-gestational-age weight. The TUNEL method was used to
demonstrate DNA fragmentation in nuclei, and a monoclonal antibody M30,
specific for a neo-epitope on cytokeratin 18, was used to identify apoptotic
epithelial cells. The positive nuclei (TUNEL) and positive cells (M30-positive
cytoplasm) were counted blindly both in villous tissue and in decidual/basal
plate tissue. M30-positive cells in villous tissues were significantly
increased in placentas from smoking mothers compared to nonsmoking mothers.
When evaluated by the TUNEL method, the difference between the two groups of
women was not significant. Our study shows that apoptosis was increased in the
placentas of smoking mothers with growth-restricted infants. The difference
between the two groups was mainly in the syncytiotrophoblast layer and in
connection with perivillous fibrin deposition. Cigarette smoke with reduction
in blood flow has previously been shown to increase apoptosis, and it is
possible that this could be one of the mechanisms playing a role in the growth
restriction.The work was performed at Magee—Womens Hospital and
Magee—Womens Institute, University of Pittsburgh, Pittsburgh, PA, USA.
1;
Deceased April 1, 2003, former address: Valley View Medical Center, 595 South
75 East, Cedar City, UT 84720, USA. 相似文献
52.
Austgulen R Chedwick L Vogt Isaksen C Vatten L Craven C 《Archives of pathology & laboratory medicine》2002,126(12):1480-1486
CONTEXT: Apoptosis occurs in the normal placenta. The monoclonal antibody M30 is directed against a novel epitope of cytokeratin 18 (CK18) that is formed by caspase cleavage early in the apoptotic cascade, and this antibody may therefore be useful for evaluating trophoblast apoptosis. OBJECTIVE: We undertook the present study to evaluate the use of monoclonal antibody M30 to assess trophoblast apoptosis in placenta at term. METHODS: We stained paraffin-embedded placental tissues from 15 deliveries at term with M30. We compared positive M30 staining and CK18 staining (as detected by a monoclonal antibody directed against CK18) of trophoblasts in serial slides. We also compared apoptotic rates as detected by M30 and TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling) in 7 of the placentas. RESULTS: In fields of villous tissue, most M30-positive cells were CK18-positive syncytiotrophoblasts. Approximately half of M30-positive cells occurred as focal positive staining in the syncytial layer, and half occurred as abundant staining of syncytiotrophoblasts in areas with increased intervillous or perivillous fibrinoid. We found very few M30-positive cells in villous stroma. In decidual/basal plate tissues, most (two thirds) of the M30-positive cells were CK18-positive extravillous trophoblasts, whereas one third were syncytiotrophoblasts of anchoring villi. Since TUNEL detects apoptosis in both epithelial and nonepithelial cells, more cells were positively stained with TUNEL than with M30 in some tissue fields. However, our observations suggest that M30 was more sensitive than TUNEL in recognizing apoptotic trophoblasts and had less nonspecific staining than TUNEL. CONCLUSION: We recommend the use of monoclonal antibody M30 for apoptosis studies in placental tissues. This antibody is easy to handle, the staining obtained seems specific, and the nonspecific staining seems negligible. 相似文献
53.
Timothy D. Smith Brent A. Craven Serena M. Engel Blaire Van Valkenburgh Valerie B. DeLeon 《Anatomical record (Hoboken, N.J. : 2007)》2021,304(1):127-138
Nasal turbinals, delicate and complex bones of the nasal cavity that support respiratory or olfactory mucosa (OM), are now easily studied using high resolution micro-computed tomography (μ-CT). Standard μ-CT currently lacks the capacity to identify OM or other mucosa types without additional radio-opaque staining techniques. However, even unstained mucosa is more radio-opaque than air, and thus mucosal thickness can be discerned. Here, we assess mucosal thickness of the nasal fossa using the cranium of a cadaveric adult dog that was μ-CT scanned with an isotropic resolution of 30 μm, and subsequently histologically sectioned and stained. After co-alignment of μ-CT slice planes to that of histology, mucosal thickness was estimated at four locations. Results based on either μ-CT or histology indicate olfactory mucosa is thicker on average compared with non-olfactory mucosa (non-OM). In addition, olfactory mucosa has a lesser degree of variability than the non-OM. Variability in the latter appears to relate mostly to the varying degree of vascularity of the lamina propria. Because of this, in structures with both specialized vascular respiratory mucosa and OM, such as the first ethmoturbinal (ET I), the range of thickness of OM and non-OM may overlap. Future work should assess the utility of diffusible iodine-based contrast enhanced CT techniques, which can differentiate epithelium from the lamina propria, to enhance our ability to differentiate mucosa types on more rostral ethmoturbinals. This is especially critical for structures such as ET I, which have mixed functional roles in many mammals. 相似文献
54.
保健食品微生物限度检查的方法学验证 总被引:3,自引:0,他引:3
目的:确认对保健食品进行微生物限度检查时,昕采用的细菌、霉菌及酵母菌计数和控制菌检查方法是否适合于该保健食品的微生物限度检查。方法:按2005年版中国药典微生物限度检查法及方法学验证实验要求,对21种保健食品进行了方法学验证。结果:10个品种(血尔口服液、金舒通胶囊、事轻松胶囊、梦玉胶囊等)分别对金黄色葡萄球菌和枯草芽孢杆菌有明显的抑菌作用,阳性对照菌回收率均低于70%。结论:保健食品采用 GB/T4789-2003食品卫生微生物学检查法进行检查时,其检验结果可能不够科学,建议参照2005年版中国药典要求,通过方法验证实验建立合理的检验方法。 相似文献
55.
Craven O 《International journal of palliative nursing》2000,6(10):501-507
In response to many influences, palliative care services in the UK are evolving rapidly, and are increasingly challenged to demonstrate equity, access and effectiveness. This article discusses the principles, philosophy and status of palliative care in the UK in the context of recent NHS developments. A case study is employed in order to critically evaluate the implementation of the palliative care approach, focusing on the specific issue of the assessment of anxiety and depression in the cancer setting. The provision of a comprehensive and integrated clinical service is a constant challenge in this patient group. In order to increase awareness and facilitate further development of patient services, and ultimately improve clinical practice, several factors are highlighted. These include the impact of multiprofessional team care, the problems inherent in the diagnosis of depression and the question of whether cancer nurses are adequately prepared to handle patients' psychological morbidity. 相似文献
56.
BA DARLOW TE INDER KB SLUIS G NUTHALL N MOGRIDGE CC WINTERBOURN 《Journal of paediatrics and child health》1995,31(4):339-344
Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
57.
Rolf J. Craven Lihui Xu Timothy M. Weiner Yih-Woei Fridell Georgette A. Dent Sudhir Srivastava Brian Varnum Edison T. Liu William G. Cance 《International journal of cancer. Journal international du cancer》1995,60(6):791-797
Using a PCR-based cloning technique, we have isolated a series of DNA fragments coding for tyrosine kinases that are expressed in a metastatic human colon tumor, and have subsequently analyzed their expression pattern at the protein level in human tumors. We identified both the α and the β forms of the platelet-derived growth factor receptor (PDGFR), axl and 8 other genes, including 3 cytoplasmic tyrosine kinases. To study their expression in human colon cancer, we performed Western blots of matched sets of normal tissues and of carcinomas from the same patient. These revealed that the α-PDGFR migrates predominantly as a 200-kDa band in 8/8 normal tissues, and as a 170-kDa band in 17/17 malignant tissues, as well as in colonic polyps, suggesting that expression of an isoform of this receptor may be a marker for the progression of colon cancer. Additional studies showed that the Axl receptor tyrosine kinase was expressed at 10-fold higher levels in a peritoneal metastatic nodule than in other normal and malignant tissues. Immunohistochemistry revealed Axl over-expression specifically in the malignant cells of the tumor. This indicates that over-expression and possibly a differential processing event of tyrosine kinase receptors may be involved in colon cancer, and that they are potential markers for the progression of this disease. © 1995 Wiley-Liss. Inc. 相似文献
58.
Cerebral palsy refers to a heterogeneous group of congenital and early acquired brain disorders. Children with cerebral palsy and other brain disorders have an increased rate of psychiatric disorder. The pattern of disorder is not particularly distinctive and no specific association has been found. We report two cases of spastic diplegia of prematurity comorbid with juvenile onset bipolar disorder, which highlight some of the diagnostic difficulties in these cases. An interesting association between the periventricular leucomalacia as an aetiological factor in cerebral palsy and the white matter lesions seen on magnetic resonance imaging in cases of bipolar disorder is noted. 相似文献
59.
60.
We have used intracellular recording techniques to examine the effects of 5-hydroxytryptamine (5-HT, serotonin) on 5-HT-containing neurones of the guinea pig dorsal raphe nucleus in vitro. Bath-applied 5-HT (30-300 microM) had two opposing effects on the membrane excitability of these cells, reflecting the activation of distinct 5-HT receptor subtypes. As demonstrated previously in the rat, 5-HT evoked a hyperpolarization and inhibition of 5-HT neurones, which appeared to involve the activation of an inwardly rectifying K(+) conductance. This hyperpolarizing response was blocked by the 5-HT(1A) receptor-selective antagonist WAY-100635 (30-100 nM). In the presence of WAY-100635, 5-HT induced a previously unreported depolarizing, excitatory response of these cells, which was often associated with an increase in the apparent input resistance of the neurone, likely due to the suppression of a K(+) conductance. Like the hyperpolarizing response to 5-HT, this depolarization could be recorded in the presence of the Na(+) channel blocker tetrodotoxin. In addition, the response was not significantly attenuated by the alpha(1)-adrenoceptor antagonist prazosin (500 nM), indicating that it is not due to the release of noradrenaline, or to the direct activation of alpha(1)-adrenoceptors by 5-HT. The 5-HT(3) receptor antagonist granisetron (1 microM) and the 5-HT(4) receptor antagonist SB 204070 (100 nM) failed to reduce the depolarizing response to 5-HT; however, ketanserin (100 nM), mesulergine (100 nM) and lysergic acid diethylamide (1 microM) significantly reduced or abolished the depolarization, indicating that this effect of 5-HT is mediated by 5-HT(2) receptors. 相似文献