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221.
This report examines the effect of filgrastim (granulocyte colony- stimulating factor, [G-CSF] in 12 patients with neutropenia [absolute neutrophil count [ANC] < 1,000/mm3]) caused by Fanconi anemia (FA). Two of 14 patients who were evaluated for study entry were ineligible because of unsuspected cytogenetic abnormalities in their bone marrow (BM). G-CSF was started at 5 micrograms/kg/d. All patients had an increase in their ANC at week 8 (mean increase = 15,664/mm3). The median ANC during therapy was 5,030/mm3. Eight of 10 patients who completed 40 weeks on study maintained an ANC > 1,500/mm3 on G-CSF given every-otherday. Four patients had an increase in their platelet count by week 8 without transfusion (maximum increase = 23,000 to 45,000/mm3); however, platelet counts fell toward baseline levels as the G-CSF dose was reduced. BM CFU-MK were increased at week 8 in three of four evaluable patients. Four patients who did not receive red blood cell transfusions had an increase in their hemoglobin level of at least 2.0 g/dL. A fifth patient had a red blood cell transfusion in week 2 and then had a similar increase in hemoglobin level without subsequent transfusion. Eight of 10 patients who completed 40 weeks of treatment showed increases in the percentage of BM CD34+ cells measured by flow cytometry. The same proportion showed increases in peripheral blood CD34+ cells. Increased BM cellularity and myeloid hyperplasia were constant findings and were associated with increased expression of the proliferating cell nuclear antigen. Adverse experiences were mild fever (1 patient) and a new BM cytogenetic abnormality at week 40 (1 patient). This study shows that prolonged administration of G-CSF exerts a stimulatory effect on the BM of FA patients and may be used to maintain a clinically adequate ANC in these patients. G-CSF has beneficial effects on multiple hematopoietic lineages in some patients and may be a good candidate for use in combination cytokine protocols for FA patients with progressive aplastic anemia. G-CSF use results in an increase in circulating CD34+ cells, a finding with important implications for future gene transfer protocols.  相似文献   
222.

Background:

Desensitization and blockade of 5-HT2C receptors (5-HT2CR) have long been thought to be central in the therapeutic action of antidepressant drugs. However, besides behavioral pharmacology studies, there is little in vivo data documenting antidepressant-induced 5-HT2CR desensitization in specific brain areas.

Methods:

Mice lacking the 5-HT reuptake carrier (5-HTT-/-) were used to model the consequences of chronic 5-HT reuptake inhibition with antidepressant drugs. The effect of this mutation on 5-HT2CR was evaluated at the behavioral (social interaction, novelty-suppressed feeding, and 5-HT2CR–induced hypolocomotion tests), the neurochemical, and the cellular (RT-qPCR, mRNA editing, and c-fos–induced expression) levels.

Results:

Although 5-HTT-/- mice had an anxiogenic profile in the novelty-suppressed feeding test, they displayed less 5-HT2CR–mediated anxiety in response to the agonist m-chlorophenylpiperazine in the social interaction test. In addition, 5-HT2CR–mediated inhibition of a stress-induced increase in 5-HT turnover, measured in various brain areas, was markedly reduced in 5-HTT-/- mutants. These indices of tolerance to 5-HT2CR stimulation were associated neither with altered levels of 5-HT2CR protein and mRNA nor with changes in pre-mRNA editing in the frontal cortex. However, basal c-fos mRNA production in cells expressing 5-HT2CR was higher in 5-HTT-/- mutants, suggesting an altered basal activity of these cells following sustained 5-HT reuptake carrier inactivation. Furthermore, the increased c-fos mRNA expression in 5-HT2CR–like immune-positive cortical cells observed in wild-type mice treated acutely with the 5-HT2CR agonist RO-60,0175 was absent in 5-HTT-/- mutants.

Conclusions:

Such blunted responsiveness of the 5-HT2CR system, observed at the cell signaling level, probably contributes to the moderation of the anxiety phenotype in 5-HTT-/- mice.  相似文献   
223.
Advances in the prenatal diagnosis of hematologic diseases   总被引:5,自引:0,他引:5  
Alter  BP 《Blood》1984,64(2):329-340
Prenatal diagnosis of hematologic diseases can now be performed with fetal blood, fetal amniotic fluid cell DNA, and fetal chorionic villi DNA. Some hemoglobinopathies can be detected by all three methods, and the choice will depend on the available obstetric and laboratory techniques, as well as the time of presentation of the pregnancy. Hopefully, further development of molecular probes and techniques will soon expand these options to all of the globin disorders. Detection of coagulation disorders in utero currently requires samples of pure fetal blood. Gene cloning is accomplished for some (factor IX and antithrombin III) and is underway for others (factor VIII), and further investigation is necessary to determine whether deficiencies in these gene products are due to gene deletion or to mutant genes linked to polymorphic restriction enzyme sites of diagnostic use. Thus, molecular biology may be applied to prenatal diagnosis of the clotting problems, but this has not yet been accomplished. Disorders affecting the number and/or function of erythrocytes, leukocytes, and platelets can be diagnosed by analysis of fetal blood. Blood samples will continue to be required until more is known about the molecular biology of hematopoiesis. Syndromes that can be diagnosed by chromosome studies should be revealed in cultures of amniotic fluid cells, fetal blood lymphocytes, and chorionic villi cells. Cultured cells can be examined for karyotypes, Y-chromatin, spontaneous or induced chromosome breakage, DNA repair, SCEs, and translocations. The techniques for culturing amniotic cells and fetal blood white cells are established, and those for growing cells from chorionic villi are improving rapidly. Direct preparations of cells from villi only may suffice for some of the above analyses. The study of hematologic disease in utero has thus come full circle, from the use of amniotic cells to determine the sex in X-linked disorders, to fetal blood sampling for the analysis of gene products, then back to amniocentesis for DNA, and now earlier in gestation to chorionic villi. All of this has occurred in less than ten years, and it is anticipated that developments in the next ten years will be equally dramatic. The future should bring all prenatal testing into the first trimester, use molecular probes, and provide for both early diagnosis and early treatment of genetic hematologic disease.  相似文献   
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Background

Heart failure treatment guidelines emphasize daily weight monitoring for patients with heart failure, but data to support this practice are lacking. Using a technology-based heart failure monitoring system, we determined whether daily reporting of weight and symptoms in patients with advanced heart failure would reduce rehospitalization and mortality rates despite aggressive guideline-driven heart failure care.

Methods

This was a randomized, controlled trial. Patients hospitalized with New York Heart Association class III or IV heart failure, with a left ventricular ejection fraction ≤35% were randomized to receive heart failure program care or heart failure program care plus the AlereNet system (Alere Medical, Reno, Nev) and followed-up for 6 months. The primary end point was 6-month hospital readmission rate. Secondary end points included mortality, heart failure hospitalization readmission rate, emergency room visitation rate, and quality of life.

Results

Two hundred eighty patients from 16 heart failure centers across the United States were randomized: 138 received the AlereNet system and 142 received standard care. Mean age was 59 ± 15 years and 68% were male. The population had very advanced heart failure, New York Heart Association class III (75%) or IV (25%), as evidenced by serum norepinepherine levels, 6-minute walk distance and outcomes. No differences in hospitalization rates were observed. There was a 56.2% reduction in mortality (P < .003) for patients randomized to the AlereNet group.

Conclusions

This is the largest multicenter, randomized trial of a technology-based daily weight and symptom-monitoring system for patients with advanced heart failure. Despite no difference in the primary end point of rehospitalization rates, mortality was significantly reduced for patients randomized to the AlereNet system without an increase in utilization, despite specialized and aggressive heart failure care in both groups.  相似文献   
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228.

Objectives

Right hemicolectomy is a common colorectal operation for resection of cancers of the right colon. The ileocolic anastomosis may be created using a stapled end-to-side, stapled side-to-side or handsewn technique. Anastomotic leak and post-operative bleeding are uncommon but serious causes of morbidity and mortality, while post-operative ileus contributes to prolonged length of stay. The aim of this study was to evaluate differences in short-term outcomes between different anastomotic configurations following right hemicolectomy for colon cancer.

Methods

We conducted a retrospective study using data from the Bowel Cancer Outcomes Registry (BCOR), including 94 hospitals across Australia and New Zealand, of all patients who underwent right hemicolectomy or extended right hemicolectomy for colon cancer with formation of a primary anastomosis between 2007 and 2021.

Results

We included 8164 patients in the analysis. There was no significant difference in rates of anastomotic leak and anastomotic bleeding based on anastomotic technique. A stapled end-to-side anastomosis was associated with a lower rate of post-operative ileus than stapled side-to-side anastomosis (6.5% vs. 7.2%; P = 0.03).

Conclusion

Both handsewn and stapled anastomosis techniques may be utilized for oncologic right hemicolectomy, with comparable rates of anastomotic leak and post-operative bleeding. Stapled end-to-side anastomosis resulted in lower rates of prolonged ileus compared to stapled side-to-side anastomoses.  相似文献   
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