The AMeX method: a multipurpose tissue-processing and paraffin-embedding method. III. Extraction and purification of RNA and application to slot-blot hybridization analysis.

RNA was extracted from tissues processed by a new fixation and paraffin-embedding method (the AMeX method) and examined by Northern blot analysis and slot-blot analysis. The RNA extraction method for AMeX-processed tissue sections after the deparaffinization step was the same as that for fresh materials. The total amount of cellular RNA extracted from AMeX-processed mouse liver tissue was slightly less than that extracted from fresh tissue. In tissues of malignant lymphoma, the total amount of cellular RNA extracted from 25 sections each 20 microns thick was about 1.6-1.8 micrograms/mm2, regardless of the histological subtype and period of storage. The extracted RNA was moderately degraded, and usually could not be used for Northern blot hybridization analysis. The intensity of ethidium bromide staining and the hybridization signals of RNA extracted from AMeX-processed tissues were usually reduced in comparison with RNA from fresh material, but specific signals could be detected by slot-blot hybridization analysis. We have demonstrated previously that the AMeX method preserves high-molecular-weight DNA and various antigens. Since the present study showed that information on mRNA can be obtained from AMeX-processed tissue, the versatility and usefulness of this method were further proven.     

The effect of a series of fixatives on the AgNOR technique

With increasing interest being shown in nucleolar organizer regions (NORs) in pathology, it was considered of great importance to evaluate the effect of some of the more commonly used and more specialized fixatives on the demonstration of these moieties. NORs can be demonstrated in paraffin sections by a silver technique (AgNOR method) which was developed from a method used by cytogeneticists for the demonstration of NORs in chromosome spreads. The degree of staining is dependent on the fixation regime employed and results may vary greatly from one fixative to another. The fixative schedules and post-treatments used in this study were based on standard sequences from the literature. We have shown that, in general, alcohol-based fixatives give optimal results, Carnoy's fluid being especially recommended. Mercurial and dichromate-containing fixatives were found to have highly detrimental effects on NOR staining. 'Routine' 10 per cent formol saline fixation gave adequate results whereas 10 per cent neutral buffered formalin gave optimal staining, similar to alcohol-based fixation.     

Machine Learning Algorithms to Predict Mortality and Allocate Palliative Care for Older Patients With Hip Fracture

ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively.     

Comorbidity and Quality of In-Hospital Care for Hip Fracture Patients

ObjectivesWe examined whether the comorbidity burden of patients with hip fracture was associated with quality of in-hospital care reflected by fulfillment of process performance measures.DesignPopulation-based cohort study using prospectively collected data from the Danish Multidisciplinary Hip Fracture Registry (DMHFR).Setting and ParticipantsPatients aged 65 years or older with an incident hip fracture from 2014 to 2018 registered in the DMHFR (n = 31,443).MethodsComorbidity was measured using the Charlson Comorbidity Index based on hospital diagnoses. Quality of in-hospital care was defined as fulfillment of eligible process performance measures, including preoperative optimization, early surgery, early mobilization, pain assessment, basic mobility, nutritional risk, need for anti-osteoporotic medication, fall prevention, and a post-discharge rehabilitation program, reflecting guideline-recommended in-hospital care. The outcomes were (1) an all-or-none composite measure defined as fulfillment of all relevant process performance measures, and (2) fulfillment of the individual process performance measures. Using binary regression, we calculated relative risk (RR) for the association between comorbidity level and outcomes.ResultsThe overall proportion of patients with hip fracture who fulfilled the all-or-none measure was 31%. Among patients with no comorbidity, 34% fulfilled the all-or-none measure versus 29% among patients with high comorbidity (Charlson ≥ 3). This corresponds to a 15% lower chance (RR = 0.85, 95% confidence interval 0.81–0.89). Increasing comorbidity was also associated with lower fulfillment of the individual process performance measures. The largest difference was seen for preoperative optimization, early surgery, and early mobilization, where patients with high comorbidity had 6% to 11% lower chance of fulfillment of these process performance measures compared with patients without comorbidity.Conclusion and ImplicationsIncreasing level of comorbidity was associated with lower quality of in-hospital care among patients with hip fracture. Our results highlight the need for tailored clinical initiatives to ensure that comorbid patients also benefit from the positive progress in hip fracture care in recent years.     

多发伤的骨折内固定

目的：认识多发伤中骨折的主要特点,探讨内固定在救治中的意义。方法：回顾1994－08～1999－08间手术救治多发伤66例,对其161处骨折中的98处进行了“仿AO技术”有关方法内固定。结果：骨折均满意愈合;涉及骨折关节51个,功能恢复满意率为96．08％。结论：在多发伤中,骨折、合并伤与并发症远较“一般骨折”复杂、严重;有效固定骨折是一种重要的救命措施;内固定手术应争取在伤后24h进行,但如受条件制约,伤后1－3wk内手术也可获得满意效果;仿AO技术中的某些方法,如拉力螺钉、张力带钢丝及自动加压钢板等,用于内固定可使骨折获得卓有成效的稳定性。     

镍钛聚髌器（NT－PC）治疗髌骨骨折

目的探讨应用NT-PC治疗髌骨骨折的方法及治疗结果。方法根据NT-PC结构及固定原理对30例髌骨骨折的治疗。结果30例髌骨骨折髌关节面均达到解剖复位,患者能下地行走,扶栏杆或徒手上下一层楼、屈膝平均达到90°的时间是1.5～3.5周。患膝关节伸、屈活动范围达到健侧水平的时间是2～10周。结论根据NT-PC的特点治疗髌骨骨折,尤其是粉碎性骨折,不但在术中容易得到髌关节面的解剖复位,而且术后能有效地将其维持,固定于解剖位直至骨质愈合。术后可早期活动,无需石膏固定,无膝关节功能障碍。     

带锁髓内针治疗股骨骨折74例

目的 探讨股骨带锁髓内针治疗股骨干骨折的临床应用价值。方法 回顾我院74例带锁钉治疗股骨干骨折的临床资料。结果 74例股骨干骨折术后能早期负重,早期功能锻炼,均骨性愈合,关节功能良好。结论 股骨带锁钉治疗股骨骨折特别是复杂的股骨干骨折疗效满意,且并发症发生率较低,带锁钉的临床应用扩大了普通髓内针的适应证。