Formaldehyde exposure and its effects during pregnancy: Recommendations for laboratory attendance based on available data

Formalin is commonly used in fixation of cadaveric specimens. Exposure to formaldehyde, a component of formalin and a known carcinogen, during gross anatomy laboratory dissection is a continuing concern for pregnant students and instructors. Since there is little literature on this specific topic, the current review was compiled in the hope of offering recommendations to pregnant students and instructors who are engaged in human anatomical dissection where formalin is used. Relevant articles were obtained through searches of PubMed and Google Scholar for the terms “formaldehyde,” “pregnant,” “formalin,” and “exposure.” A literature search was conducted for chemical information and articles about exposure as issued by government regulatory agencies and chemical companies that produce formaldehyde. This led to the compilation of 29 articles each of which included references to previous, relevant, human research. The reviewed literature contains data strongly suggesting that pregnancy can be affected by formaldehyde exposure. Therefore, on the basis our analysis, female students who might be pregnant should avoid formaldehyde exposure, including that in a gross anatomy laboratory. Instructors should find other means of ensuring anatomical competence for these students. Clin. Anat. 28:972–979, 2015. © 2015 Wiley Periodicals, Inc.     

A decline in prosocial language helps explain public disapproval of the US Congress

Talking about helping others makes a person seem warm and leads to social approval. This work examines the real world consequences of this basic, social-cognitive phenomenon by examining whether record-low levels of public approval of the US Congress may, in part, be a product of declining use of prosocial language during Congressional debates. A text analysis of all 124 million words spoken in the House of Representatives between 1996 and 2014 found that declining levels of prosocial language strongly predicted public disapproval of Congress 6 mo later. Warm, prosocial language still predicted public approval when removing the effects of societal and global factors (e.g., the September 11 attacks) and Congressional efficacy (e.g., passing bills), suggesting that prosocial language has an independent, direct effect on social approval.As recently as 2002, public approval of Congress was reliably over 50% and as high as 84%. In late 2013, though, public approval reached an all-time low, with less than 10% of Americans expressing support (1). What caused this dramatic decline in public approval in just over a decade? One explanation is that the public held Congress responsible for societal and global problems (e.g., a weak economy) (2, 3). A second explanation is that the public disapproves of ineffective governance. For example, public approval of Congress tends to drop when Republicans and Democrats are polarized against one another and when Congress conflicts with the President (4, 5). We test a third explanation that has less to do with action and more to do with talk (6). We suggest that recent public disapproval partly resulted from the disappearance of warm, prosocial language in Congressional discourse.Previous experimental research has shown that presenting a warm and prosocial demeanor increases social approval (7). People reveal a wealth of information about their feelings and intentions through verbal communication (8–10). The speaker’s underlying motives notwithstanding, talking about helping others makes positive impressions upon an audience (11). We investigated whether this well-documented finding can explain public perceptions of Congress. Specifically, we asked whether the recent rise of public disapproval of Congress is predicted by declining prosocial language of elected representatives.To measure prosocial language, we computer analyzed all 123,927,807 words spoken in session of the US House of Representatives between 1996 and 2014. Our approach was to look for linguistic markers of prosocial language; we used content analysis software (12) to calculate the proportion of words in the target text that matched entries in a validated dictionary of prosocial words (13). We then compared levels of prosocial language within each month of Congress with their approval ratings by the American public (14) and found a striking match. Fig. 1 shows that levels of prosocial language and the public’s approval followed the same trajectory between 1996 and 2014, r(204) = 0.55, P < 0.001. Notably, the language of both Democrats, r(204) = 0.53, P < 0.001, and Republicans, r(204) = 0.54, P < 0.001, predicted the public’s approval of Congress.Open in a separate windowFig. 1.Prosocial language within the US Congress predicts the public’s approval of Congress. (A) Prosocial language represents the density of prosocial words in the in-session speeches of members of the US House of Representatives. (B) Public approval is Gallup survey data. Individual data points represent monthly scores. Solid lines connect 2-y session means.Public approval peaked in the aftermath of the September 11 attacks, declined over the next 7 y, rose slightly in the wake of the 2008 financial crisis, and then declined again. Prosocial language followed a nearly identical trajectory. In the years spanning 2002 and 2014, a small (19%) decrease in prosocial language ushered in a large (75%) decrease in public approval. The individual words whose use most strongly predicted public approval were as follows: gentle, involve, educate, contribute, concerned, give, tolerate, trust, and cooperate.The correlation between prosocial language and public approval does not necessarily imply that representatives’ language caused the public to approve of them. The reverse could be true: The public’s approval could cause changes in the topics that representatives raised. If one variable were causing the other, the causal factor would have changed first and the effected factor second. We tested which variable changed first in time by assessing the association between prosocial language in the present and public approval with time lags of up to 50 mo in the past and future (Fig. 2). The distribution of the associations across the time lags nearly perfectly fitted a normal distribution curve, r(98) = 0.97, P < 0.001. The maximum association between prosocial language and public approval was at +6.7 mo, meaning that what Congress says today best predicts their public approval ratings 29 wk into the future.Open in a separate windowFig. 2.Time-lagged associations between prosocial language and public approval of the US Congress. How representatives speak today best predicts their public approval ratings 6.7 mo into the future.Another concern with the present data is the possibility that some exogenous factor (e.g., the September 11 attacks) caused changes in both language and public approval. We reasoned that, if operative, societal and global factors would also have influenced the US President’s language and/or the economy. Alternatively, dysfunctional governance may cause both politicians’ rhetoric to be less civil and the public to disapprove (SI Text and Table S1). To test whether prosocial language has an independent, direct effect on the public sentiment, we ran a regression analysis in which we controlled for the effects of both societal/global factors (in the form of the President’s prosocial language, US unemployment rate, and US consumer expectations about the economy) and competent governance (in the form of partisan conflict, the number of bills that Congress passed, and Presidential vetoes). Even with these conservative controls, prosocial language within Congress still predicted the public’s approval (

Airflow Simulations in Infant,Child, and Adult Pulmonary Conducting Airways

The airway structure continuously evolves from birth to adulthood, influencing airflow dynamics and respiratory mechanics. We currently know very little about how airflow patterns change throughout early life and its impact on airway resistance, namely because of experimental limitations. To uncover differences in respiratory dynamics between age groups, we performed subject-specific airflow simulations in an infant, child, and adult conducting airways. Airflow throughout the respiration cycle was calculated by coupling image-based models of the conducting airways to the global respiratory mechanics, where flow was driven by a pressure differential. Trachea diameter was 19, 9, and 4.5 mm for the adult (36 years, female), child (6 years, male), and infant (0.25 years, female), respectively. Mean Reynolds number within the trachea was nearly the same for each subject (1100) and Womersley number was above unity for all three subjects and largest for the adult, highlighting the significance of transient effects. In general, air speeds and airway resistances within the conducting airways were inversely correlated with age; the 3D pressure drop was highest in the infant model. These simulations provide new insight into age-dependent flow dynamics throughout the respiration cycle within subject-specific airways.     

四肢关节专用低场强MRI评估对膝关节损伤的诊断价值

目的：分析四肢关节专用低场强MRI诊断膝关节损伤的临床应用价值。 方法：于2004-12/2005-10解放军总医院全军骨科研究所收治经手术、关节镜检查或临床证实的膝关节损伤患者40例（43个膝关节）。应用Atorscan0.2T永磁型四肢关节专用低场强磁共振机,对膝关节损伤的MRI表现进行分析。 结果：四肢关节专用低场强MRI对半月板、前交叉韧带、骨挫伤等均可作出正确诊断。 结论：四肢关节专用低场强MRI对膝关节损伤的综合诊断具有重要意义,是膝关节损伤较理想的一种非创伤性检查方法。     

人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中构建组织工程软骨

目的:观察人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中初步构建组织工程软骨的可行性。方法:实验于2005-04/2006-05在解放军总医院骨科研究所完成。脂肪组织和关节软骨均来自膝关节置换术中切除的组织,并经患者知情同意。关节软骨冻干后经粉碎机粉碎,过筛,选取25～38μm大小的软骨微粒。在样品中先加入2.5g/L胰蛋白酶,37℃消化24h,再加入1%Triton X-100震荡72h。将软骨微粒和蒸馏水按1∶3的比例混合后滴加在模板中,置入冷冻干燥机冻干后行紫外线交联。紫外线照射8h完成。最后经25kGy 60Co辐照灭菌完成支架制备。取膝关节置换术中切除的髌下脂肪垫,酶消法获得脂肪干细胞,扩增后复合于脱细胞软骨基质制成圆柱状三维支架上(细胞密度5×1010L-1),置于生物反应器中进行诱导培养,同时设静态培养组作为对照,3周后观测大体形态和组织学形态变化,同时进行组织化学(包括番红花O,阿利新蓝染色)和Ⅱ型胶原免疫组织化学分析。结果:生物反应器组诱导培养3周苏木精-伊红染色显示支架结构消失,只有中心区域残存少量支架结构;静态培养组支架结构尚存在,有少量基质分泌。番红花O染色显示生物反应器组细胞外有大量蛋白聚糖沉积,阿利新蓝染色表明有软骨特异性蛋白多糖的聚集;而静态培养组只有部分区域染色且淡于生物反应器组。Ⅰ型胶原免疫组化的结果显示,在生物反应器组细胞能够合成大量软骨细胞特异性胶原成分,而静态培养组呈弱阳性。结论:生物反应器培养明显促进了脂肪干细胞的增殖与软骨分化,是体外构建组织工程软骨的良好方法。     

Percutaneous umbilical blood sampling and umbilical vein transfusions. Rapid serologic differentiation of fetal blood from maternal blood

Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.     

Electronic verification of donor-recipient compatibility: the computer crossmatch

Background: This article describes standard operating procedures (SOPs) for a computer crossmatch to replace the immediate-spin crossmatch for ABO incompatibility between patient blood samples submitted for pretransfusion testing and the blood component selected for transfusion. These SOPs were developed following recent changes to the Standards for Blood Banks and Transfusion Services of the American Association of Blood Banks (AABB). Study Design and Methods: SOPs were developed, utilizing currently available software, for pretransfusion testing. The SOP for donor unit processing entails bar code entry of the unit number, component name, and ABO/Rh type; computer entry and interpretation of serologic reactions; warning of discrepancies between bar code-entered blood type and result interpretation; and quarantine of the donor unit in such instances. The SOP for patient sample testing requires bar code entry of specimen accession number, which accesses patient demographics; computer entry and interpretation of ABO/Rh tests; repeat blood typing at the time of crossmatch if only one patient blood type is on record; and warning if there are nonconcordant current and historical blood types. The computer crossmatch SOP requires bar code entry of specimen accession and donor unit numbers; release of group O red cells pending resolution of discrepancies; and immediate-spin crossmatch during computer downtime. Tables validated on- site prompt warning messages and prevent both computer crossmatch and release if blood components of the wrong ABO type are selected. Results: These SOPs meet the requirements of the 15th edition of the AABB Standards. Projected annual time savings at this institution are > 100,000 workload recording units. Further benefits include reduced patient sample volume requirements, less handling of biohazardous material, and elimination of unwanted positive or negative reactions associated with the immediate-spin crossmatch. Release of incompatible blood components when the wrong patient blood type is on record is addressed by requiring the use of group O red cells in the absence of two concordant blood types, one of which must be from a current sample. Conclusion: A combination of existing computer programs and carefully developed SOPs can provide a safe and efficient means of detecting donor-recipient incompatibility without performance of serologic crossmatch.     

Discrepancies in reverse ABO typing due to prozone

Three group O sera manifesting prozone in reverse ABO tests are reported. All were implicated in erroneous blood typing results. One sample failed to react with A1 red cells (RBCs) in immediate-spin (IS) tests, had anti-A and -B titers of 8192 and 2048, respectively, by indirect antiglobulin technique (IAT), and was from a diabetic patient; the parenteral administration of A substance present in porcine insulin is a possible cause of hyperimmunity in this case. The second sample was from the recipient of a single unit of group B fresh-frozen plasma; the serum anti-A and -B titers were 10,240 by IAT, but only weak reactions with A1 and B RBCs were noted in routine IS reverse typing tests; the hyperimmunity in the patient concerned was likely due to crossreacting anti-A, B stimulated by B-active glycoproteins and/or glycolipids in the transfused plasma. The third serum also had anti-A and anti-B IAT titers of 10,240 but did not react with A1 and B RBCs by IS; the hyperimmunity in this case may be related to sepsis from intestinal flora carrying A- and/or B-like antigens. These antibodies lysed A1 and/or B RBCs in tests incubated at room temperature (RT) and strongly agglutinated those RBCs by IS when diluted 10-fold with saline. The absence of the prozone phenomenon in tests with RBCs suspended in diluents containing EDTA is consistent with the previously published mechanism for anti-A prozone: namely, the steric hindrance of agglutination by the C1 component of human complement.(ABSTRACT TRUNCATED AT 250 WORDS)     

Can the reading for serologic reactivity following 37 degrees C incubation be omitted?

The need to detect antibodies that agglutinate and/or hemolyze red cells (RBCs) directly at 37 degrees C, but do not react in subsequently performed indirect antiglobulin tests (IATs), is of concern relative to the streamlining and automation of antibody detection methods. To determine incidence and significance of such reactions, data from 87,480 tests, which used low-ionic-strength saline, 10-minute incubation at 37 degrees C, and anti-IgG, were analyzed for unexpected antibodies. There were 3590 positive tests, of which 475 showed reactions at 37 degrees C but not in subsequently performed IATs (37 + IAT-). Of these, 196 reactions were due to autoantibodies or other factors usually considered insignificant with respect to the survival of transfused incompatible RBCs, 176 were due to alloantibodies of questionable clinical significance (M, Lea, P1, etc.), and 103 were associated with alloantibodies of potential clinical significance (63 E, 27 K, 5 Jka, 4 D, 3 cE, and 1 C). This latter reaction was seen in 72 patients, with two 37 + IAT-antibodies occurring in each of 3 patients. Of the 75 potentially significant 37 + IAT-antibodies, 57 were seen in patients recently exposed to homologous RBCs, 13 in patients with a history of transfusion and/or pregnancy, and 5 in patients with no known exposure to homologous RBCs. IAT reactivity was observed in subsequent samples with 27 of these antibodies. The predictive value of a 37 + IAT-test was 21.7 percent for a potentially significant antibody. The incidence was 0.12 percent of all tests for unexpected antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)