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61.
62.
Bank  WO; Kerber  CW; Cromwell  LD 《Radiology》1981,139(3):609-616
From November 1976 to September 1979, 46 patients with intracranial arteriovenous malformations or fistulas participated in a clinical study using isobutyl 2-cyanoacrylate (IBCA), with tantalum, for palliative or preoperative occlusion of the blood supply to the abnormalities. Although failure to obtain satisfactory position of a functioning microcatheter precluded deposition of IBCA 10 times, a total of 51 of a possible 62 feeding vessels were occluded with the tantalum-impregnated glue. The technique, results, and complications are discussed in light of the clinical follow-up, which varied from 12 to 48 months.  相似文献   
63.
64.

Background and Purpose

Previous work in our laboratory showed opioid agents inhibit cytokine expression in astrocytes. Recently, Watkins and colleagues hypothesized that opioid agonists activate toll-like receptor 4 (TLR4) signalling, which leads to neuroinflammation. To test this hypothesis, we characterized LPS and opioid effects on TLR4 signalling in reporter cells.

Experimental Approach

NF-κB reporter cells expressing high levels of TLR4 were used to compare LPS and opioid effects on NF-κB activation, a pathway activated by TLR4 stimulation.

Key Results

LPS increased TLR4 signalling in a concentration-dependent manner and was antagonized by LPS antagonist (LPS-RS, from Rhodobacter sphaeroides). A concentration ratio analysis showed that LPS-RS was a competitive antagonist. The opioid agonists, morphine and fentanyl, produced minor activation of TLR4 signalling when given alone. When tested following LPS stimulation, opioid agonists inhibited NF-κB activation but this inhibition was not blocked by the general opioid antagonist, naloxone, nor by the selective μ opioid receptor antagonist, β-FNA. Indeed, both naloxone and β-FNA also inhibited NF-κB activation in reporter cells. Further examination of fentanyl and β-FNA effects revealed that both opioid agents inhibited LPS signalling in a non-competitive fashion.

Conclusions and Implications

These results show that LPS-RS is a competitive antagonist at the TLR4 complex, and that both opioid agonists and antagonists inhibit LPS signalling in a non-competitive fashion through a non-GPCR, opioid site(s) in the TLR4 signalling pathway. If confirmed, existing opioid agents or other drug molecules more selective at this novel site may provide a new therapeutic approach to the treatment of neuroinflammation.  相似文献   
65.
This in-depth ethnographic study examines the processes, barriers and impacts experienced by Mainland Chinese caregivers residing in rural Yunnan for disclosing HIV status to their adolescents born with the infection and other community members. In particular, highlighted are their associated personal, social, relational and cultural vulnerabilities. A purposeful sample of 13 pairs of HIV-born adolescents between the ages of 11–19 years and their primary caregivers were recruited in December 2014. The Conceptual Model Sexual Health Disclosure (CMSHD) was modified with Chinese culturally specific adaptation to guide the exploration of the complex aspects of the adolescents and caregiver’s relationships. All interviews were audiotaped, transcribed verbatim and then translated into English.

Complex sociocultural interactions emerging in these dyadic interviews included guilt, shame, unintended disclosure, the need for secrecy, perceived stigma, ‘loss of face’, protection of parents, inability to support their families and deep concerns over lineage and future marriage prospects amongst the parents, which had significant psychosocial and even physical impacts for these adolescents born with HIV and their families. Frontline health-care workers and HIV peer support programs are recommended to counteract China’s current top-down biomedical disease-related approach to health services. It is crucial to provide instrumental avenues of confidential psychosocial support including disclosure approaches for caregivers of HIV positive adolescents within a uniquely Chinese cultural context.  相似文献   

66.
Cytogenetic analysis of acute lymphoblastic leukemia (ALL) of childhood identified nonrandom chromosomal abnormalities of the short arm of chromosome 12. The alterations include deletions that are thought to be indicative of the presence of a tumor suppressor gene that is mutated on the remaining allele. To refine further the chromosomal localization of this gene, we analyzed the loss of heterozygosity (LOH) of chromosome 12 in 100 primary ALL samples using 22 polymorphic markers and identified two distinct smallest common deleted regions on chromosome 12p13. One region is flanked by D12S77 and D12S98 and has a size of 4 cM. Twenty-six percent of informative patients showed LOH in this region. This region may contain the TEL gene. The other region is flanked by D12S269 and D12S308 including the KIP1 gene. Forty-four percent of informative patients showed LOH in this second region. Mutational analysis of KIP1 using polymerase chain reaction-single- strand conformation polymorphism analysis and Southern blot analysis showed no homozygous deletions and point mutations suggesting that the altered gene in this second region is not the KIP1. Clinical data showed that LOH of 12p was demonstrated more frequently in precursor-B ALLs (32 of 80; 40%) than in T-ALLs (1 of 20; 5%) (P = .0027). Furthermore, patients with 12p LOH were younger (P = .013), with a lower DNA index (P = .046), but they had the same survival rates at 3 years. In summary, these data suggest that two different tumor suppressor genes are on chromosome arm 12p, which act separately in the development of childhood precursor-B ALLs. One of the tumor suppressor genes is in the region the KIP1 gene, but our data suggest this gene is not abnormal. The other target is in the region of the TEL gene; and this candidate deserves further study.  相似文献   
67.
Conventional high‐grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis‐free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti‐apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell‐cycle arrest; Chk1 protein levels were attenuated and ATR–Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven‐depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven‐controlled ATR–Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix‐embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR–Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
68.
Esophageal atresia(EA) is one of the most common congenital digestive malformations and requires surgical correction early in life. Dedicated centers have reported survival rates up to 95%. The most frequent comorbidities after EA repair are dysphagia(72%) and gastroesophageal reflux(GER)(67%). Chronic GER after EA repair might lead to mucosal damage, esophageal stricturing, Barrett's esophagus and eventually esophageal adenocarcinoma. Several long-term follow-up studies found an increased risk of Barrett's esophagus and esophageal carcinoma in EA patients, both at a relatively young age. Given these findings, the recent ESPGHAN-NASPGHAN guideline recommends routine endoscopy in adults born with EA. We report a series of four EA patients who developed a carcinoma of the gastrointestinal tract: three esophageal carcinoma and one colorectal carcinoma in a colonic interposition. These cases emphasize the importance of lifelong screening of the upper gastrointestinal tract in EA patients.  相似文献   
69.

Background

Infantile colic is a common painful clinical condition associated with signs of distended intestines and an increase in colon peristalsis. However, clinical documentation of observed gastrointestinal functions in the condition is still lacking. Even though the ailment is common, no clear treatment guidelines exist. While acupuncture with minimal stimulation has been shown to be effective in reducing crying behaviour of infants suffering from colic, the documented effect of acupuncture on gastrointestinal function in children with infantile colic is scarce. This case series study aims to document the symptoms of routinely rated gastrointestinal function and the changes in these symptoms after minimal acupuncture in a larger group of children with infantile colic.

Methods

This study included 913 infants with normal weights, and lengths at birth. The infants' mean age was 5.4 weeks when the observations started, and had colic symptoms since two weeks after birth. Light needling stimulation of the acupuncture point LI4 was performed for 10-20 seconds bilaterally on a daily basis for a mean of 6.2 consecutive days. A questionnaire with verbal rating scales for the parents' evaluation was used before and after the treatment period.

Results

Before treatment the infants were assessed by the parents in terms of 'often have inflated stomachs' (99%) and 'seldom drool' (76%), 'regurgitate' (53%) and 'belch' (62%). Moreover, the reported frequency of defecation was 5-8 times per day (64%), with a yellowish-green colour (61%) and with a water-thin consistency (74%). After treatment, the variables of inflated stomachs, drooling and regurgitating were systematically changed, and rated by the parents as occurring 'sometimes' while belching was rated as occurring 'often' and the frequency of defecation was reduced to 1-4 times/day with a mustard yellow colour and a gruel-like consistency. The parents also rated their impression of the infants' general colic symptoms including crying behaviour as much ameliorated in 76% of the cases.

Conclusion

The results of the present study show that minimal acupuncture at LI4 in infantile colic is an effective and easy treatment procedure that, furthermore, is reported to be without serious side effects.  相似文献   
70.
The development of debilitating complications represents a major heathcare burden associated with the treatment of diabetes. Despite advances in new therapies for controlling hyperglycemia, the burden associated with diabetic complications remains high, especially in relation to cardiovascular and renal complications. Furthermore, an increasing proportion of patients develop type 2 diabetes at a younger age, putting them at higher risk of developing complications as a result of the increased exposure to hyperglycemia. Diabetes has become the main contributing cause to end‐stage renal disease in most countries. Although there has been important breakthroughs in our understanding of the genetics of type 1 and type 2 diabetes, bringing important insights towards the pathogenesis of diabetes, there has been comparatively less progress in our understanding of the genetic basis of diabetic complications. Genome‐wide association studies are beginning to expand our understanding of the genetic architecture relating to diabetic complications. Improved understanding of the genetic basis of diabetic cardiorenal complications might provide an opportunity for improved risk prediction, as well as the development of new therapies.  相似文献   
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