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11.
Theodore A. Henderson Robert W. Rhoades Carol A. Bennett-Clarke Pat A. Osborne Eugene M. Johnson Mark F. Jacquin 《The Journal of comparative neurology》1993,336(2):243-260
Prior studies indicate that neonatal nerve injury kills many trigeminal (V) first- and second-order cells, and interrupts pattern formation in the brainstem and cerebral cortex. Yet it is not known whether effects upon cell survival and pattern formation are causally related. To determine whether axotomized V ganglion cells can be rescued by an exogenous trophic agent, rats received 5 mg/kg of nerve growth factor (NGF) prior to, and every day after, infraorbital nerve section on the day of birth until sacrifice on postnatal day (PND) 1, 3, 5, 7, or 14. Other animals received identical lesions without NGF. Ganglion cell numbers were significantly reduced by PNDl in pups not given NGF, while NGF-treated rats displayed no significant cell loss through PND7. However, NGF did not permanently rescue V neurons because ganglion cell numbers were reliably reduced by PND14. Cell numbers in V nucleus principalis were reduced by PNDl in pups not given NGF, while NGF-treated animals displayed no cell loss through PND14. NGF's rescue of second-order cells is probably an indirect effect of NGF actions upon V ganglion cells because, in other newborns, NGF failed to maintain principalis cells after direct lesion of the left V ganglion. To determine whether preventing cell death permits whisker-related pattern formation, other rats also received NGF prior to and after infraorbital nerve section at birth. After 3–14 days, patterns were assessed in the brainstem and cortex with cytochrome oxidase histochemistry and serotonin immunocytochemistry. Whisker-related patterns failed to develop as in cases not given NGF. These data indicate that communication with the periphery is necessary for the maintenance of central whisker-related patterns. They also suggest that V ganglion cells can be rescued, albeit temporarily, from rapid injury-induced death by NGF, thereby delaying injury-induced cell death in nucleus principalis. However, the mechanism(s) responsible for injury-induced pattern alterations in the developing V system remains to be elucidated. © 1993 Wiley-Liss, Inc. 相似文献
12.
Marlene Duarte Giles Andrea L Nelson Felisa Shizgal Eva-Marie Stern Anne Fourt Pat Woods Judith I Langmuir Catherine C Classen 《Journal of trauma & dissociation》2007,8(4):7-24
This article describes the Women Recovering from Abuse Program (WRAP), an outpatient day-hospital program for women suffering from the sequelae of childhood abuse. WRAP was conceived in 1998 by clinicians who advocated for its development based on a growing need to provide women who had experienced childhood trauma an alternative to an inpatient program. WRAP draws from a Stage 1 treatment approach to address chronic interpersonal trauma and dissociation by incorporating psychopharmacology, individual and group psychotherapy. The program is structured into two phases: a preparatory Building Resources Group (BRG) and an intensive multimodal segment comprised of seven types of group therapy. Each group is described in terms of the treatment rationale and its structure and process. Two research studies to date support the effectiveness of WRAP. 相似文献
13.
Upton S Stadter CS Landis P Wulfsberg EA 《American journal of medical genetics. Part A》2003,(4):338-341
Six children with Kabuki syndrome were studied to investigate speech patterns associated with the syndrome. Each child's speech was characterized with regard to articulation (types of errors and intelligibility), pitch (high or low), loudness (volume of speech), and prosody (general quality of speech that combines rate and inflection). All six children had a history of delayed speech and language acquisition and were receiving speech services. All individuals had articulation errors and abnormal oral resonance, which appeared to be due to poor oral-motor coordination and hypotonia and were not felt to be due to structural abnormalities such as velopharyngeal insufficiency, dental malocclusion, or cleft palate. An intriguing finding, noted in the two individuals followed from childhood into adolescence with serial speech evaluations, was that pitch, loudness, and prosody did not mature over time and what was age appropriate performance at younger ages became inappropriate in adolescence. This raises a challenge for speech services, as by adolescence, while articulation had improved, the pitch and loudness of these individuals' speech had not and so was noticeably different from peers. Distinctive speech characteristics with a lack of normal maturation during childhood can be added to the extensive list of clinical features associated with the Kabuki syndrome and hopefully will lead to improved speech/language treatment for individuals with this syndrome. 相似文献
14.
Massimo Pignatelli Tareq W. Ansari Pat Gunter Dan Liu Shinji Hirano Masatoshi Takeichi Günter Klppel Nicholas R. Lemoine 《The Journal of pathology》1994,174(4):243-248
Epithelial cadherin (E-cadherin) is a Ca2+-dependent cell-cell adhesion molecule that connects cells via homotypic interactions. Its function is critical in the induction and maintenance of cell polarity and differentiation, and its loss of downregulation is associated with an invasive and poorly differentiated phenotype in colon and other tumours. We have used an avidin-biotin immunoperoxidase technique to localize E-cadherin in microwave-treated, paraffin-embedded sections from 36 patients with pancreatic adenocarcinomas. E-cadherin was expressed by normal ductal and acinar cells with typical membranous staining at the intercellular junctions. Loss of normal surface E-cadherin expression was found in 19/36 (53 per cent) tumours compared to the adjacent normal ductal cells. Abnormal E-cadherin expression was found more frequently in poorly differentiated (grade III) (6/7, 86 per cent) than in well-differentiated tumours (grade I) (4/14, 28 per cent) (P=0·012). Membranous E-cadherin expression was also lost more frequently in primary tumours with lymph node (stage III) (14/23, 61 per cent) and distant metastasis (stage IV) (2/2, 100 per cent) compared with 3/11 (27 per cent) lymph node-negative tumours (stage I) (P=0·043). In conclusions, our data indicate that loss of membranous E-cadherin expression is associated with high grade and advanced stage in pancreatic cancer. 相似文献
15.
The identification of circulating endothelial progenitor cells (EPCs) has prompted an explosion of interest in postnatal vasculogenesis and the role of this mechanism in human health and disease. Previously considered restricted to the embryonic phase, the differentiation in situ of progenitor cells to vascular endothelium is now known to occur in the adult. A role for EPCs in the modulation of angiogenesis has also been recognized. These cells are enriched in the mononuclear cell fraction of peripheral blood but have also been isolated from bone marrow, the vessel wall, and a number of other organs and tissues. Accumulating data suggest an important vasculoprotective function for EPCs, although a maladaptive role underpinning a variety of angiogenesis-dependent diseases is also being investigated. Encouraging results observed with experimental and early human trials of EPC-based regenerative therapies have further underscored the significance of this recently discovered cell type. Notwithstanding the scope and pace of these developments, a number of challenges remain: the precise ontogeny and lineage of these cells is unknown, the true extent to which EPCs participate in neovascularization and vascular repair is still uncertain, and the efficacy of EPC-based regenerative therapies has yet to be proven in randomized controlled trials. 相似文献
16.
Left ventricular outflow tract obstruction associated with chronic ventricular assist device support
Baradarian S Dembitsky WP Jaski B Abolhoda A Adamson R Chillcot S Daily PO 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(6):665-667
Favorable long-term patient outcome after insertion of a left ventricular assist device (LVAD) as a bridge to recovery or destination therapy for the treatment of end-stage cardiomyopathy is adversely affected by pathophysiologic changes affecting the heart. Alterations in the native aortic valve apparatus, specifically aortic valve cusp fusion, is an example of such a phenomenon and may especially affect patients in cases of bridge to recovery, a rare but reported event. A retrospective review of the last 33 LVAD placements at our institution was conducted, including reviews of operative reports and pathologic examinations of the native hearts. Seven hearts were found to have varying degrees of aortic valve cusp fusion after chronic LVAD support (63-1, 339 days). Five of these patients had native aortic valves, and two had bioprosthetic valves. The left ventricular outflow tracts in two patients were surgically occluded at the time of LVAD insertion. Aortic valve cusp fusion occurs in roughly 25% of patients on chronic LVAD support. This phenomenon may prove to be clinically significant by creating a potential source of emboli and infection. In addition, in the case of myocardial recovery, left ventricular outflow tract obstruction could limit parallel flow and produce suprasystemic ventricular pressures that in turn would elevate left ventricular end diastolic pressures. The latter may contribute to further myocardial injury, ultimately limiting the ability of an otherwise recovered heart to be weaned from LVAD support. 相似文献
17.
18.
Tarnowski Kenneth J.; Gavaghan Mary Pat; Wisniewski Jack J. 《Journal of pediatric psychology》1989,14(3):463-472
Examined the effects of pain symptom severity and patient diagnosticstatus on pediatric staffs' acceptability ratings of 6 interventionsused to treat pediatric pain. Results indicated that (a) extinctionwas significantly less acceptable than all other behavioraland pharmacologic interventions, (b) self-management was moreacceptable than all other interventions with the exception ofcontingency management, (c) accelerative procedures and self-managementinterventions were preferred to pharmacologic treatment, (d)patient diagnostic status and pain symptom severity failed tosignificantly influence treatment ratings, (e) self-managementwas the only intervention differentially rated as a functionof pain symptom severity, and (f) pharmacologic treatment wasdifferentially rated as a function of patient diagnostic status. 相似文献
19.
Bebo BF Adlard K Schuster JC Unsicker L Vandenbark AA Offner H 《Journal of neuroscience research》1999,55(4):432-440
Mechanisms that contribute to increased female susceptibility to multiple sclerosis can be studied in the murine model of experimental autoimmune encephalomyelitis (EAE). In this report, we compared oral tolerance induction in male and female B10.PL mice using fed myelin basic protein (MBP) Ac1-11 peptide or a high-affinity analogue, Ac1-11[4Y]. We found that fed Ac1-11[4Y] peptide, but not native Ac1-11, could limit cellular infiltration into the central nervous system (CNS) and protect male mice from EAE, an effect that was completely obviated by castration. In contrast, female mice could not be orally tolerized or protected from EAE with either peptide. Tolerance induction in males was reflected by the appearance of Ac1-11[4Y]-reactive splenocytes that produced a sharply increased ratio of transforming growth factor (TGF)-beta:interleukin (IL)-2 and induced bystander suppression. These data directly demonstrate gender differences in regulatory T cells, and support the concept that androgens are involved in governing oral tolerance to EAE. 相似文献
20.
Pilot study of a visitor volunteer programme for community elderly people receiving home health care
MacIntyre I Corradetti P Roberts J Browne G Watt S Lane A 《Health & social care in the community》1999,7(3):225-232
There is a need to evaluate community support programmes for elderly people. In this randomized control trial (RCT), we determined the effectiveness of 'friendly visitors' in a volunteer programme of a visiting nurses organization in Southern Ontario, Canada. The Volunteer Friendly Visitor Programme was developed to support elderly people receiving homemaking and nursing care in the community. Volunteers are screened, trained, interviewed and matched to homebound elderly clients for general interest, visit expectations and personality. Volunteers spend three to four hours on average per week with clients socializing in mutually agreed-upon ways. The nursing staff identified clients who were lonely for this additional support. These newly-referred clients were randomly allocated to receive a friendly visitor or not for six weeks. Those receiving the volunteer visitor improved in life satisfaction and two social support measures: worth and social integration. Thus, the addition of volunteer visitors to planned homemaking and nursing care made a difference for elderly in the community. 相似文献