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121.
One approach to the analysis of ethical dilemmas in medical practice uses the "four principles plus scope" approach. These principles are: respect for autonomy, beneficence, non-maleficence and justice, along with concern for their scope of application. However, conflicts between the different principles are commonplace in psychiatric practice, especially in forensic psychiatry, where duties to patients often conflict with duties to third parties such as the public. This article seeks to highlight some of the specific ethical dilemmas encountered in forensic psychiatry: the excessive use of segregation for the protection of others, the ethics of using mechanical restraint when clinically beneficial and the use of physical treatment without consent. We argue that justice, as a principle, should be paramount in forensic psychiatry, and that there is a need for a more specific code of ethics to cover specialised areas of medicine like forensic psychiatry. This code should specify that in cases of conflict between different principles, justice should gain precedence over the other principles. 相似文献
122.
Diagnostic utility of array-based comparative genomic hybridization in a clinical setting 总被引:1,自引:0,他引:1
Baris HN Tan WH Kimonis VE Irons MB 《American journal of medical genetics. Part A》2007,(21):2523-2533
Array-based comparative genomic hybridization is a recently introduced technique for the detection of submicroscopic genomic imbalances (deletions or duplications) across the entire genome. To assess the potential utility of a widely available array-based comparative genomic hybridization platform that targets specific, clinically relevant, loci across the genome for cytogenetic diagnosis in a clinical setting, we reviewed the medical records of all 373 patients at Children's Hospital Boston who had normal chromosomal analysis and were tested with this targeted array-based comparative genomic hybridization over a 1-year period from November 1, 2004 to October 31, 2005. These patients were tested because of a suspicion of chromosomal abnormalities based on their clinical presentation. Thirty-six patients (9.7%) had abnormal array-based comparative genomic hybridization results. Twenty patients (5.4%) had potentially pathogenetic genomic imbalances and 16 patients (4.3%) had copy number variations that are not believed to be pathogenetic. Thirteen of 234 patients (5.6%) with mental retardation/global developmental delay, 10/114 patients (8.8%) with facial dysmorphism, 5/58 patients (8.6%) with multiple congenital anomalies, and 4/35 patients (11.4%) with both facial dysmorphism and multiple congenital anomalies had potentially pathogenetic genomic imbalances. Targeted array-based comparative genomic hybridization is a clinically available test that is useful in the evaluation of patients suspected of having chromosomal disorders. However, it is best used as an adjunct to chromosomal analysis when a clear genetic diagnosis is unavailable. 相似文献
123.
Development of a focused oligonucleotide-array comparative genomic hybridization chip for clinical diagnosis of genomic imbalance 总被引:1,自引:0,他引:1
Shen Y Irons M Miller DT Cheung SW Lip V Sheng X Tomaszewicz K Shao H Fang H Tang HS Irons M Walsh CA Platt O Gusella JF Wu BL 《Clinical chemistry》2007,53(12):2051-2059
BACKGROUND: Submicroscopic genomic imbalance underlies well-defined microdeletion and microduplication syndromes and contributes to general developmental disorders such as mental retardation and autism. Array comparative genomic hybridization (CGH) complements routine cytogenetic methods such as karyotyping and fluorescence in situ hybridization (FISH) for the detection of genomic imbalance. Oligonucleotide arrays in particular offer advantages in ease of manufacturing, but standard arrays for single-nucleotide polymorphism genotyping or linkage analysis offer variable coverage in clinically relevant regions. We report the design and validation of a focused oligonucleotide-array CGH assay for clinical laboratory diagnosis of genomic imbalance. METHODS: We selected >10 000 60-mer oligonucleotide features from Agilent's eArray probe library to interrogate all subtelomeric and pericentromeric regions and 95 additional clinically relevant regions for a total of 179 loci. Sensitivity and specificity were measured for 105 patient samples, including 51 with known genomic-imbalance events, as detected by bacterial artificial chromosome-based array CGH, FISH, or multiplex ligation-dependent probe amplification. RESULTS: Focused array CGH detected all known regions of genomic imbalance in 51 validation samples with 100% concordance and an excellent signal-to-noise ratio. The mean SD among log(2) ratios of all noncontrol features without copy number alteration was 0.062 (median, 0.055). Clinical testing of another 211 samples from individuals with developmental delay, unexplained mental retardation, dysmorphic features, or multiple congenital anomalies revealed genomic imbalance in 25 samples (11.9%). CONCLUSIONS: This focused oligonucleotide-array CGH assay, a flexible, robust method for clinically diagnosing genetic disorders associated with genomic imbalance, offers appreciable advantages over currently available platforms. 相似文献
124.
Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion 总被引:14,自引:0,他引:14
HM Rinder ; M Murphy ; JG Mitchell ; J Stocks ; KA Ault ; RS Hillman 《Transfusion》1991,31(5):409-414
Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
125.
Joseph?H.?MarcotteEmail authorView authors OrcID profile Kinjal?Patel Ronak?Desai John?P.?Gaughan Deviney?Rattigan Kevin?W.?Cahill Robin?F.?Irons Justin?Dy Monika?Dobrowolski Helena?McElhenney Michael?Kwiatt Steven?McClane 《International journal of colorectal disease》2018,33(9):1259-1267
Purpose
Fluid management within Enhanced Recovery After Surgery (ERAS) protocols is designed to maintain a euvolemic state avoiding the negative sequelae of hypervolemia or hypovolemia. We sought to determine the effect of a recent ERAS protocol implementation on kidney function and on the incidence of postoperative acute kidney injury (AKI).Methods
A total of 132 elective colorectal resections performed using our ERAS protocol were compared to a propensity-matched group prior to ERAS implementation. Fluid balance, urine output, creatinine, and blood urea nitrogen (BUN) were recorded for all patients, and the incidence of AKI was determined according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria.Results
Implementation of our ERAS protocol decreased average postoperative length of hospital stay (5.5 vs 7.7 days, p <?0.0001) and time to return of bowel function (2.5 vs 4.1 days, p <?0.0001). The rate of postoperative AKI increased following implementation of the protocol (11.4 vs 2.3%, p <?0.0001). However, by the time of discharge, the average creatinine of ERAS patients who had experienced AKI had returned to their preoperative baseline values (p =?0.9037). Significant univariate predictors of AKI in ERAS patients were longer operative times (p <?0.01) and the diagnosis of diverticulitis (p <?0.01). Within our ERAS patients, AKI was associated with a prolonged postoperative length of hospital stay (p <?0.01).Conclusions
Despite the proven benefits of the Enhanced Recovery After Surgery (ERAS) protocols, care should be taken during protocol implementation to monitor for and to prevent acute kidney injury.126.
Clonal rearrangements of the Ig heavy chain (IGH) locus occur in nearly all cases of B-cell precursor acute leukemia (BCP-ALL). Some of these rearrangements may be detected by polymerase chain reaction (PCR) using VH gene framework III (FRIII) and JH consensus primers. However, about 20% of BCP-ALLs fail to amplify with this technique. To determine the causes of these PCR failures and to investigate any possible association with specific subgroups of disease, we analyzed 72 acute leukemias of defined immunophenotype and cytogenetics, comparing FRIII with VH-family leader-specific PCR methods and Southern blotting. Of 37 BCP-ALL cases, 6 (16.2%) failed totally to amplify with FRIII and JH primers. None of these cases amplified with VH leader primers. Additionally, all cases retained germline VH6 genes and 5 of 11 rearranged alleles amplified with a consensus DH primer, indicating that these rearrangements represented biallelic DH-JH recombinations. Among the 6 FRIII and VH leader PCR-negative BCP-ALL cases, there was no common immunophenotype or consistent cytogenetic abnormality, although all showed structural chromosomal abnormalities and 3 of 5 successfully karyotyped had abnormalities of chromosome 12p. 13 cases with t(9;22)(q34;q11) Philadelphia chromosome-positive [Ph+]) and IGH rearrangements (9 BCP-ALL and 4 biphenotypic cases) were also analyzed. Of 23 rearranged IGH alleles, 19 (82%) were positive by FRIII PCR, and all 4 remaining alleles were amplified by VH leader primers. Use of the leader primers in these Ph+ cases also detected 3 additional clonal rearrangements that were not anticipated from Southern blotting; such unexpected bands were not observed in 21 other Ph- cases. The additional bands represented "new" and unrelated VH rearrangements rather than VH-VH replacement events. We conclude that biallelic DHJH rearrangements occur in a subgroup of BCP-ALL; in these cases, the activation of the full VHDHJH recombination mechanism had not occurred. Therefore, these cases of BCP-ALL were arrested at an early stage of B- cell differentiation. In contrast, all Ph+ BCP-ALLs and biphenotypic acute leukemias, which may represent the transformation of multipotent hemopoietic stem cells, had undergone VHDHJH recombination. Of 9 Ph+ BCP-ALL cases, 3 also showed ongoing VHDHJH rearrangement, reflecting the persistent expression of the VHDHJH recombinase. Finally, sequence analysis of 33 rearranged VHDHJH genes showed that only 3 including 2 Ph+ BCP-ALL maintained an intact open-reading frame. Loss of the open- reading frame occurred not only because of out-of-frame VHDH and DHJH joining, but also because of VH gene mutation and deletion. These data show that most BCP-ALLs may represent the neoplastic transformation of BCPs destined to die in the bone marrow. 相似文献
127.
128.
CML patients in blast crisis have breakpoints localized to a specific region of the BCR 总被引:1,自引:0,他引:1
Schaefer-Rego K; Dudek H; Popenoe D; Arlin Z; Mears JG; Bank A; Leibowitz D 《Blood》1987,70(2):448-455
Chronic myelogenous leukemia (CML) is associated with the Philadelphia (Ph) chromosome, which results from a reciprocal translocation between chromosomes 9 and 22. This activates the abl oncogene by moving it from chromosome 9 and combining it with sequence located on chromosome 22. The new fusion gene, with chromosome 22 sequence at its 5' end and chromosome 9-abl sequence at its 3' end, generates a new messenger RNA (mRNA) and protein that are implicated in the pathogenesis of CML. The breakpoint near the c-abl locus on chromosome 9 can occur within a large area. In contrast, the breakpoints on chromosome 22 are concentrated within a 6 kilobase (kb) region termed the breakpoint cluster region (bcr). This study was designed to determine whether chronic-phase and blast crisis patients had identifiable differences in the structure of their Ph chromosomes. Restriction mapping of the chromosome 22 translocation breakpoints performed for 26 patients showed that the breakpoints of eight of the nine patients in blast crisis were in the 3' portion of the bcr, whereas the breakpoints in the 17 patients in the chronic phase were clustered in the 5' portion of the bcr. This suggests a strong correlation between a 3' bcr breakpoint and blast crisis in CML. 相似文献
129.
Drug-induced thrombocytopenia is associated with increased binding of IgG to platelets both in vivo and in vitro 总被引:3,自引:0,他引:3
Kelton JG; Meltzer D; Moore J; Giles AR; Wilson WE; Barr R; Hirsh J; Neame PB; Powers PJ; Walker I; Bianchi F; Carter CJ 《Blood》1981,58(3):524-529
Thrombocytopenia is a common serious adverse effect of drug treatment. A variety of in vitro diagnostic techniques to confirm the diagnosis are available, but the majority lack sufficient sensitivity to detect all cases of drug-induced thrombocytopenia. We studied 19 patients with suspected drug-induced thrombocytopenia and demonstrated that platelet- associated IgG (PAIgG) was elevated in all at the time of thrombocytopenia, and PAIgG returned to normal levels as the thrombocytopenia resolved. In the majority of patients, the platelet count rapidly returned to normal after the drug was discontinued; however, in six patients, the thrombocytopenia persisted well beyond the period of time that the offending drug would be expected to be cleared from the blood. In 13 patients, serum obtained after recovery was used to identify the drug responsible for the thrombocytopenia in an in vitro assay. In all cases, the addition of the drug historically associated with the thrombocytopenic episode was associated with an increased binding of IgG to control platelets. For uncertain reasons, the concentration of drug required to increase the in vitro binding of IgG to test platelets was often more than the concentration usually achieved in vivo. Wider application of these techniques may provide better understanding of the clinical characteristics and mechanisms responsible for drug-induce thrombocytopenia. 相似文献
130.
Many patients with thrombotic thrombocytopenic purpura (TTP) have a platelet aggregating factor in their serum that may be pathologically linked with the disease process. To help characterize the type of platelet aggregation and platelet release induced by the sera from seven TTP patients, we measured the ability of a variety of inhibitors of platelet function as well as the ability of monoclonal antibodies (MoAbs) against platelet glycoproteins to inhibit TTP sera-induced platelet aggregation and release. These results were compared with the ability of the same inhibitors to block platelet aggregation induced by ristocetin, collagen, ADP, thrombin, and IgG-immune complexes. Monoclonal antibody directed against platelet glycoprotein Ib totally inhibited ristocetin-induced aggregation and release but had no effect on aggregation and release induced by the TTP sera or by any of the other platelet agonists. However, the MoAb against glycoproteins IIb/IIIa inhibited aggregation and release caused by TTP sera as well as by collagen, thrombin, and ADP but had no effect on aggregation and release induced by ristocetin. The aggregating activity could be abolished by heparin but not by the serine protease inhibitor PMSF (1 mmol/L). And although monomeric human IgG and purified Fc fragments of IgG inhibited IgG-immune complex-induced aggregation and release, they had no effect on TTP sera-induced aggregation and release nor on aggregation and release induced by any of the other agonists. Consistent with these in vitro studies showing no effect of IgG were the in vivo observations that intravenous (IV) IgG was without effect when administered to three patients with TTP. This study indicates that although a von Willebrand factor (vWF)-rich preparation of cryoprecipitate enhances the in vitro platelet aggregation and release caused by sera from the seven TTP patients we studied, the pathway of aggregation and release is not via platelet glycoprotein Ib. Also the aggregating factor of TTP sera is not neutralized in vitro or in vivo by IgG. 相似文献