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1.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献
2.
3.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
4.
Modulation of cyclic nucleotide levels in peripheral nerve without effect on resting or compound action potentials. 下载免费PDF全文
1. Cyclic nucleotide levels and compound action potential magnitudes were measured in frog sciatic nerves following exposure to carbachol, isoprenaline and cyclic nucleotide related substances. 2. The resting cyclic AMP level was 2-4 p-mole/mg protein and the cyclic GMP level was 0-27 p-mole/mg protein in desheathed nerves. 3. Isoprenaline (100 micrometer) caused a twofold increase in cyclic AMP without affecting cyclic GMP levels. Carbachol (100 micrometer) caused a twofold increase in cyclic GMP without affecting cyclic AMP levels. 4. The phosphodiesterase inhibitor theophylline (5 mM) augmented both cyclic AMP and cyclic GMP. 5. The magnitude of the resting or compound action potential was not affected by isoprenaline, carbachol, or phosphodiesterase inhibitors. 6. The cyclic nucleotides and their butyryl derivatives did not affect the magnitude of the resting or compound action potential, either when applied alone or in the presence of a phosphodiesterase inhibitor. 7. In contrast to sympatic tissue we conclude that hormone mediated cyclic nucleotide metabolism in peripheral nerve is unrelated to control of axonal excitability. 相似文献
5.
Andrew Daly Steven McAfee Bimal Dey Christine Colby Leah Schulte Beow Yeap Robert Sackstein Nancy J Tarbell David Sachs Megan Sykes Thomas R Spitzer 《Biology of blood and marrow transplantation》2003,9(6):373-382
Infections are a common complication of allogeneic bone marrow transplantation and the leading cause of transplantation-related mortality. It had been hypothesized that transplantation following nonmyeloablative preparative regimens would result in fewer infections by causing less mucosal injury, less graft-versus-host disease, and allowing earlier immune reconstitution. We have retrospectively reviewed the infectious complications of 65 consecutive patients with advanced hematologic malignancies who underwent bone marrow transplantation using a novel preparative regimen consisting of cyclophosphamide, thymic irradiation, and in vivo T-cell depletion. Cytomegalovirus (CMV) infection occurred in 52% of cases in which the donor or recipient had evidence of prior CMV exposure. Using a strategy of preemptive therapy and secondary prophylaxis with ganciclovir, no CMV disease occurred. Infections with gram-positive bacteria predominated over the first 100 days after bone marrow transplantation. Thereafter, the relative proportion of gram-negative infections increased without a significant increase in episodes of neutropenia. The rate of bacterial infections was not influenced by relapse of the underlying malignancy. Seven patients developed infections with Aspergillus species, which was the most common infectious cause of death in these patients. Infections with viruses other than CMV (n=10) and with protozoan organisms (n=2) also occurred. The use of HLA-mismatched donors, the occurrence of grade II-IV acute graft-versus-host disease, and treatment with corticosteroids did not influence the risk of CMV or bacterial or fungal infections in patients who underwent transplantation following this preparative regimen. Overall, the incidence and spectrum of infections in this series was similar to the reported incidence of infections following conventional myeloablative allogeneic stem cell transplantation. We conclude that a quantitative T-cell deficiency in these extensively T-cell depleted patients may be a risk factor for infection, even in the absence of graft-versus-host disease. 相似文献
6.
Anderson RA; Wallace AM; Kicman AT; Wu FC 《Human reproduction (Oxford, England)》1997,12(8):1657-1662
Administration of supraphysiological doses of testosterone to normal men
causes inhibition of spermatogenesis, but while most become azoospermic,
30-55% maintain a low rate of spermatogenesis. We have investigated whether
there are differences in endogenous androgen production, of testicular and
adrenal origin, which may be related to the degree of suppression of
spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m.
injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic,
while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a
specific testicular product, was reduced to <10% of pretreatment values,
with no differences between the groups. Similar results were obtained for
other markers of testicular steroidogenesis. Urinary and plasma adrenal
androgens were also reduced during TE treatment: a statistically
significant decrease in both (P < 0.001 and P < 0.05 respectively)
was seen in the azoospermic but not oligozoospermic responders. These
results suggest that testicular steroidogenesis is decreased to <10% by
the administration of supraphysiological doses of exogenous testosterone.
Differences in the degree of ongoing steroidogenesis in the testis do not
appear to account for incomplete suppression of spermatogenesis, thus
differences in androgen metabolism may underlie this heterogeneous
response. A small but significant reduction in secretion of adrenal
androgens was also detectable, the relevance of which is unclear.
相似文献
7.
A prospective study of hemostatic abnormalities in 108 cancer patients was undertken at an oncology clinic in a university teaching hospital. Tests included Quick prothrombin time, activated partial thromboplastin time, thrombin time, platelet count, modified Ivy bleeding time, fibrinogen, fibrin degradation products (FDP), euglobulin lysis time, protamine sulfate test, and factor V, VII, VIII and X assays. Ninety-eight per cent of the patients had one or more abnormal coagulation tests. The commonest abnormalities were elevated fibrin degradation products and prolonged thrombin time. Thrombocytosis occurred in 57% of patients, hyperfibrinogenemia in 46%, thrombocytopenia in 11%, and non had hypofibrinogenmia. It is suggested that platelet count, fibrinogen concentration, and serum FDP assay are the most useful tests in assessing the hemostatic abnormalities in cancer patients, although thrombin time, factor V assay, and bleeding time may also be helpful. The peripheral blood smears of 53 patients were reviewed, and only one showed microangiopathic hemolytic anemia. The data illustrate that subclinical coagulopathy is relatively frequent in patients with malignancy. 相似文献
8.
Tamanini F; Willemsen R; van Unen L; Bontekoe C; Galjaard H; Oostra BA; Hoogeveen AT 《Human molecular genetics》1997,6(8):1315-1322
Lack of expression of the fragile X mental retardation protein (FMRP)
results in mental retardation and macroorchidism, seen as the major
pathological symptoms in fragile X patients. FMRP is a cytoplasmic RNA-
binding protein which cosediments with the 60S ribosomal subunit. Recently,
two proteins homologous to FMRP were discovered: FXR1 and FXR2. These novel
proteins interact with FMRP and with each other and they are also
associated with the 60S ribosomal subunit. Here, we studied the expression
pattern of the three proteins in brain and testis by immunohistochemistry.
In adult brain, FMR1, FXR1 and FXR2 proteins are coexpressed in the
cytoplasm of specific differentiated neurons only. However, we observed a
different expression pattern in fetal brain as well as in adult and fetal
testis, suggesting independent functions for the three proteins in those
tissues during embryonic development and adult life.
相似文献
9.
Laparoscopic fusion of the lumbar spine: minimally invasive spine surgery. A prospective multicenter study evaluating open and laparoscopic lumbar fusion 总被引:19,自引:0,他引:19
STUDY DESIGN: Two hundred-forty consecutive patients underwent laparoscopic instrumented interbody fusion using custom-designed instrumentation and BAK (Sulzer Spine Tech, Minneapolis, MN) fusion cages. The surgeries were performed at eight spine centers during U.S. Food and Drug Administration investigational device evaluation clinical trials. This cohort was compared with 591 consecutive patients undergoing open anterior fusion with the same device. OBJECTIVES: To investigate the feasibility and safety of the laparoscopic approach compared with that of open procedures. SUMMARY OF BACKGROUND DATA: In other areas of medicine, advances in laparoscopic surgical procedures have resulted in reduced morbidity, expense, and pain when compared with results of the open counterpart. METHODS: The open anterior procedure was performed using a retroperitoneal approach. The laparoscopic procedure was performed transperitoneally with carbon dioxide insufflation to provide visualization using a 10-mm endoscope. Two hollow, titanium, threaded interbody implants packed with autologous bone were inserted into the diseased interspace. RESULTS: The laparoscopy group had a shorter hospital stay and reduced blood loss but had increased operative time. Operative time improved in the laparoscopy group as surgeons' experience increased. Operative complications were comparable in both groups, with an occurrence of 4.2% in the open approach and 4.9% in the laparoscopic approach. Overall, the device-related reoperation rate was higher in the laparoscopy group (4.7% vs. 2.3%), primarily as a result of intraoperative disc herniation. Conversion to open procedure in the laparoscopy group was 10%, with most cases predictable and preventable. CONCLUSIONS: The laparoscopic procedure is associated with a learning curve, but once mastered, it is effective and safe when compared with open techniques of fusion. 相似文献
10.