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1.
William A. Marston MD ; Anton Usala MD ; Ronald S. Hill PhD ; Robert Mendes MD ; Mary-Ann Minsley RN 《Wound repair and regeneration》2005,13(3):243-247
A novel injectable scaffolding matrix (E-Matrix) has been developed to accelerate wound healing in diabetic foot ulcers. This porcine collagen-derived matrix is designed to mimic tertiary embryonic connective tissue and to stimulate fetal wound repair mechanisms including angiogenesis. In vitro and animal studies have indicated a beneficial effect on tissue growth and an acceptable safety profile. In this report, we describe the initial use of this product in a pilot study of six humans with chronic nonhealing diabetic foot ulcers. A dramatic initial response to injection was seen, with an average wound size reduction of 72% 2 weeks after injection. Randomized trials are underway to define the potential benefit of this new treatment modality for diabetic foot ulcers. 相似文献
2.
Peter L. Choyke Gladys M. Glenn Joseph P. Wagner Irina A. Lubensky Kailash Thakore Bert Zbar W. Marston Linehan McClellan M. Walther 《Urology》1997,49(6):926-931
Objectives. Epididymal cystadenomas (ECs) are frequently found in association with von Hippel-Lindau disease (VHL), but little has been reported about their sonographic appearance. We review the sonographic appearance of ECs, the relationship of ECs to other manifestations of VHL, and the specific genetic mutations associated with ECs.Methods. Fifty-six male patients with VHL were examined with scrotal sonography and physical examination as part of a larger screening program for VHL. The head of the epididymis was measured in two planes on sonography and compared with age-matched normal controls. All VHL patients with palpable epididymal abnormalities or enlargement (more than two standard deviations) of the head of the epididymis on ultrasound were considered positive for EC.Results. Thirty of 56 (54%) male patients with VHL demonstrated a unilateral (n = 10; 33%) or bilateral (n = 20; 67%) solid abnormality in the head of the epididymis suggestive of EC. Sonographic appearances ranged from a solid mass with multiple tiny cysts to an almost completely solid mass. The most common appearance was a 15- to 20-mm solid mass with small cystic components. Dilated efferent ductules were seen within the testicle in 7 men, evidently a result of chronic obstruction. There was no association between the clinical subtype of VHL and the presence of ECs (P >0.10, chi square). Mutations resulting in a truncated gene product were associated with the development of ECs but the association did not reach statistical significance (P = 0.06).Conclusions. ECs are a common manifestation of VHL in men and exhibit a range of appearances on ultrasound. Sonography can be used to identify ECs and determine the extent of cystic dilation of the rete testes. The benign course of ECs and the usual absence of clinical symptoms favor a conservative approach to their management. 相似文献
3.
4.
H A Bull R M Pittilo J Drury J G Pollock J M Clarke N Woolf A Marston S J Machin 《The British journal of surgery》1988,75(7):671-674
Canine abdominal aortas have been replaced with Dacron arterial prostheses to assess the effects of mesothelial cell seeding on graft prostacyclin and thromboxane A2 release. At both 2 weeks and 6 weeks after surgery, three seeded and two unseeded control grafts were examined for prostacyclin release. In addition, thromboxane release was assessed in one seeded and one unseeded graft. Sections of aorta and graft were removed and incubated in PBS containing either 10 microM calcium ionophore A23187 or 20 microM arachidonic acid. The incubation mixture was sub-sampled at 5 min intervals over a 20 min period to assess the progressive release of prostacyclin and thromboxane A2 using a radioimmunoassay for 6-keto-prostaglandin F1 alpha and thromboxane B2 respectively. In seeded grafts, 6-keto-prostaglandin F1 alpha release averaged 15 per cent compared with aorta at 2 weeks and 45 per cent compared with aorta at 6 weeks. By contrast, release from unseeded grafts was undetectable at 2 weeks; however, by 6 weeks there was some release amounting to 15 per cent compared with aorta. There was a statistically significant increase in the release of 6-keto-prostaglandin F1 alpha from mesothelial cell seeded grafts at 6 weeks compared with unseeded grafts (P less than 0.01). Thromboxane release from the graft sections was variable and unrelated to whether the grafts had been seeded or not. These preliminary results, showing that grafts seeded with autologous peritoneal mesothelial cells release more prostacyclin than unseeded grafts, further highlight the role of the mesothelial cell as an alternative to the endothelial cell for improving the patency of arterial Dacron prostheses in the early postoperative days. 相似文献
5.
One hundred and one participants received In Control: A Home Video Freedom from Smoking Program. Of 53 completing self-treatment, 31 were verified by CO testing as abstinent one month after completion. Twenty-one per cent of the sample (40 per cent of those completing treatment) had not smoked in the past three months prior to 12 month follow-up and 16 per cent of the total sample (30 per cent of those completing treatment) had not smoked at all in the past 11 months. 相似文献
6.
People with intellectual disability, sensory impairments and behaviour disorder: a case series 总被引:1,自引:0,他引:1
Background Sensory impairments (SIs) are more prevalent in people with intellectual disability (ID). Both conditions lead to higher rates of emotional and behavioural problems than in the general population. The identification of psychiatric disorders in this group can be difficult, particularly in those with severe ID and limited communication skills. Method The present paper presents a series of 18 case reports of individuals with ID, SI and behavioural problems. Results The majority of cases were young male caucasians with congenital rubella syndrome and autistic spectrum disorder, referred because of self‐injurious behaviour (SIB) or aggression. Nine cases were treated with autidepressants, five underwent environmental changes and two had medication reduced. All showed some improvement. Conclusions The benefits of comprehensive assessments, the use of standardized assessment tools and trials of treatments are discussed in the context of making psychiatric diagnoses. 相似文献
7.
Mapping the Von Hippel -- Lindau disease tumour suppressor gene: identification of germline deletions by pulsed field gel electrophoresis 总被引:3,自引:0,他引:3
Richards Frances M.; Phipps Maude E.; Latlf Farida; Yao Masahlro; Crossey Paul A.; Foster Kelth; Llnehan W. Marston; Affara Nabeel A.; Lerman Michael I.; Zbar Berton; Ferguson-Smith Malcolm A.; Maher Eamonn R. 《Human molecular genetics》1993,2(7):879-882
Von HlppelLindau (VHL) disease is a dominantly Inheritedfamillal cancer syndrome In which affected individuals havea greatly increased predisposition to the development of haemangloblastomasof the central nervous system and retina, renal cell carcinomaand phaeochromocytoma. The VHL gene has been mapped to chromosome3p25 -p26 by genetic linkage studies and we have previouslydemonstrated that the VHL gene is tightly linked to the D3S601locus (Zmax = 18.86 at 相似文献
8.
Diagnosis of pneumococcal pneumonia by psaA PCR analysis of lung aspirates from adult patients in Kenya 总被引:2,自引:0,他引:2
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psaA is the gene encoding pneumococcal surface adhesin A (PsaA), a 37-kDa protein expressed on the surface of Streptococcus pneumoniae. PCR primers for psaA have been shown to amplify the target DNA sequence in all 90 serotypes of S. pneumoniae and in none of 67 heterologous pathogens and colonizing bacteria of the upper respiratory tract. Pathogenic bacteria identified in lung aspirate specimens cannot normally be dismissed as contaminants or colonizers, which limit the assay specificity of other respiratory tract specimens. psaA PCR analysis was evaluated in 171 lung aspirates from Kenyan adults with acute pneumonia. The limit of detection was one genome equivalent. Sensitivity, estimated in 35 culture-positive lung aspirates, was 0.83 (95% confidence interval, 0.70 to 0.95). psaA PCR analysis extended the number of identifications of S. pneumoniae in lung aspirates from 35 on culture to 61 by both methods. Of 26 new pneumococcal diagnoses, 19 were corroborated by results of blood culture or urine antigen detection. Sequences of the PCR products from 12 positive samples were identical to the psaA target gene fragment. Using an internal control for the PCR, inhibition of psaA PCR was demonstrated in 17% (8 of 47) of false-negative specimens. The results of a control PCR for the human gene beta-actin suggested that false-negative psaA PCR results are attributable to problems of specimen collection, processing, or DNA extraction in 30% of cases (14 of 47). psaA PCR analysis is a sensitive tool for diagnosis of pneumococcal pneumonia in adults. 相似文献
9.
B J Everitt T W Robbins J L Evenden H M Marston G H Jones T E Sirki? 《Neuroscience》1987,22(2):441-469
The effects of ibotenic acid-induced lesions of the ventral pallidum/substantia innominata region, the dorsal pallidum or both on the acquisition and retention of a conditional visual discrimination have been studied in the rat. Lesions of the ventral pallidum and large lesions of the dorsal and ventral pallidum severely impaired both the acquisition and retention of the conditional discrimination. Dorsal pallidal lesions had similar, but less marked effects. The same lesions also impaired the retention of a passive avoidance task, but had no effect on a conditioned taste aversion. Neurobiological investigations revealed that the lesions destroyed cholinergic neurons in the magnocellular nucleus basalis and caused reductions in cortical choline acetyltransferase activity of about 30-40%. Tract-tracing experiments indicated that the lesions destroyed, in particular, cholinergic neurons projecting to the frontal dorsolateral cortex and also those projecting to more posterior cortex, but not the occipital lobes. Contingency analysis of the behavioural, neurochemical and neuroanatomical data indicated that those animals with the largest decreases in choline acetyltransferase activity, or the largest areas of neuronal loss in the ventral and dorsal globus pallidus, were most impaired in the retention of the conditional discrimination. The results do not, therefore, indicate a simple relationship between cholinergic neuronal loss and the retention of response rules essential for performance of the task ("reference memory"). The relevance of the results to cholinergic hypotheses of learning and memory is discussed. 相似文献
10.
Michael A Tangrea Rodrigo F Chuaqui John W Gillespie Mamoun Ahram Gallya Gannot Benjamin S Wallis Carolyn J M Best W Marston Linehan Lance A Liotta Thomas J Pohida Robert F Bonner Michael R Emmert-Buck 《Diagnostic molecular pathology》2004,13(4):207-212
Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting. Expression microdissection (xMD) offers significant advantages over available methods, including an increase in dissection speed of several orders of magnitude. xMD may become a valuable tool for investigators studying cancer or other disease states in patient specimens and animal models. 相似文献