On the limited consensus of mountain pine beetle impacts on wildfire.

Context: The mountain pine beetle (MPB; Dendroctonus ponderosae) is a native bark beetle whose outbreaks leads to widespread conifer forest mortality. Of particular concern to forest and wildfire managers is the influence of MPB outbreaks on wildfire via spatial legacies left in impacted forest stands. There is, however, limited consensus in the literature regarding how MPB outbreaks affect wildfire across western North America. Objectives: This meta-analysis aims to (1) summarize available evidence regarding MPB-wildfire interactions, and (2) identify environmental and methodological indicators associated with various wildfire responses (i.e., amplified, neutral, or dampened) post-outbreak. Methods: We include peer-reviewed publications focusing on MPB outbreaks and subsequent wildfire activity in forests across western Canada and the USA between 2000 and 2021. A classification scheme was used to examine attributes of each publication to assess which indicators contribute most to their associated wildfire response. Results: We found that spatial scale, forest fuels, and weather are main drivers of variation in wildfire response post-outbreak. Metrics of forest fuels and inclusion of weather data on a stand-scale are related to amplified fire responses, whereas dampened responses correspond to landscape-scale analyses. Furthermore, red-stage stands are associated with amplified fire response, whereas other stages are associated with dampened response-supporting current conceptual models of the importance of outbreak stage on wildfire. Conclusions: Advancing our understanding regarding drivers of wildfire responses post-MPB outbreak is key to developing accurate, and comparative research studies. These findings provide crucial information for wildfire, and forest management agencies, especially in forests newly exposed to this disturbance interaction under climate change. Supplementary Information: The online version contains supplementary material available at 10.1007/s10980-023-01720-z.

Using standardised patients in an objective structured clinical examination as a patient safety tool.

Standardised patients (SPs) are a powerful form of simulation that has now become commonplace in training and assessment in medical education throughout the world. Standardised patients are individuals, with or without actual disease, who have been trained to portray a medical case in a consistent manner. They are now the gold standard for measuring the competence of physicians and other health professionals, and the quality of their practice. A common way in which SPs are used in performance assessment has been as part of an objective structured clinical examination (OSCE). The use of an SP based OSCE can be a powerful tool in measuring continued competence in human reliability and skill performance where such skills are a critical attribute to maintaining patient safety. This article will describe how an OSCE could be used as a patient safety tool based on cases derived from actual events related to postdonation information in the blood collection process. The OSCE was developed as a competency examination for health history takers. Postdonation information events in the blood collection process account for the majority of errors reported to the US Food and Drug Administration. SP based assessment is an important patient safety tool that could be applied to a variety of patient safety settings and situations, and should be considered an important weapon in the war on medical error and patient harm.

Pressure sore prevention in hospital patients: a clinical audit.

Pressure sores cause significant mortality and morbidity as well as being a financial burden on health-care services. Reduction of pressure sore incidence is a Department of Health priority. Pressure sores are accepted as largely preventable complications of illness and disability and the means to achieve prevention are available. The aim of this clinical audit was to identify potential contributing factors to pressure sore acquisition in an acute hospital setting. The results suggest that substantial changes in the approach to clinical management may be needed.

Sensitization of hematopoietic stem and progenitor cells to trimetrexate using nucleoside transport inhibitors.

Antifolates such as methotrexate (MTX) and trimetrexate (TMTX) are widely used in the treatment of cancer and nonmalignant disorders. Transient, yet sometimes severe myelosuppression is an important limitation to the use of these drugs. It has previously been shown that clonogenic myeloid progenitors and colony-forming units-spleen are resistant to antifolates, suggesting that myelotoxicity occurs late in hematopoietic development. The goal of this study was to define the mechanisms by which primitive hematopoietic cells resist the toxic effects of antifolate drugs. To test the hypothesis that myeloid progenitors may salvage extracellular nucleotide precursors to resist TMTX toxicity, a defined liquid culture system was developed to measure TMTX toxicity in expanding progenitor populations. These in vitro experiments showed that both human and murine progenitors can resist TMTX toxicity by importing thymidine and hypoxanthine from the serum. As predicted from these findings, several drugs that block thymidine transport sensitized progenitors to TMTX in vitro, although to differing degrees. These nucleoside transport inhibitors were used to test whether progenitors and hematopoietic stem cells (HSCs) could be sensitized to TMTX in vivo. Treatment of mice with TMTX and nitrobenzylmercaptopurineriboside phosphate (NBMPR-P), a potent transport inhibitor, caused significant depletions of clonogenic progenitors within the bone marrow (20-fold) and spleen (6-fold). Furthermore, NBMPR-P administration dramatically sensitized HSCs to TMTX, with dual-treated mice showing a greater than 90% reduction in bone marrow repopulating activity. These studies demonstrate that both myeloid progenitor cells and HSCs resist TMTX by using nucleotide salvage mechanisms and that these pathways can be pharmacologically blocked in vivo using nucleoside transport inhibitors. These results have important implications regarding the use of transport inhibitors for cancer therapy and for using variants of dihydrofolate reductase for in vivo selection of genetically modified HSCs.

Cell-specific expression of beta-amyloid precursor protein isoform mRNAs and proteins in neurons and astrocytes.

The abnormal accumulation of beta-amyloid (A beta) in senile plaques appears to be a central pathological process in Alzheimer's disease. A beta is formed by proteolysis of beta-amyloid precursor protein (APP) with several isoforms generated by alternative splicing of exons 7, 8 and 15. A semi-quantitative reverse transcription (RT)-polymerase chain reaction (PCR) analysis showed that APP695 mRNA lacking exon 7 and 8 was most abundant in primary cultures of rat neurons, while APP770 and APP751 representing, respectively, the full length and exon 8 lacking isoforms predominated in cultured astroglial cells. Antisera AP-2 and AP-4 were produced by immunizing rabbits with keyhole limpet haemocyanin coupled with synthetic peptides representing KPI region APP301-316 and A beta region APP670-686 of APP770, respectively. These polyclonal antisera were purified against the corresponding peptide using affinity chromatography. Western blot analysis of homogenates of relatively enriched neuronal and astroglial cultures showed that these antibodies discretely stained bands of proteins in a cell-specific manner. Dot-blot analysis using AP-2, AP-4 and 22C11 antibodies indicated that, in comparison with neurons, cultured astrocytes contained 3-fold greater KPI-containing APP isoform proteins. The amount of total APP proteins, which include both KPI-containing and KPI-lacking APP isoforms, was approximately 90% higher in astrocytes than in neurons. Consistent with these in vitro findings in cultured astrocytes, in fimbria-fornix lesioned rat hippocampus, labelling with AP-2 antibody, which specifically reacts with KPI-containing APP proteins, was mainly observed in glial fibrillary acidic protein-positive reactive astrocytes in vivo. The results showed that APP isoforms are expressed in a cell type-specific manner in the brain and, since deposition of A beta is closely associated with the expression of KPI-containing APP isoforms, provide further evidence for the involvement of astrocytes in plaque biogenesis.

Evaluation of 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid in the inhibition of rouleaux formation.

BACKGROUND: DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid) inhibits the formation of serum-or plasma-induced rouleaux through its ability to bind to band 3 on red cell membranes. This property of DIDS was evaluated in the serologic testing of specimens exhibiting rouleaux. STUDY DESIGN AND METHODS: Optimal test conditions for DIDS treatment of reagent red cells were determined by varying the volume and concentration of DIDS solution and the incubation temperature and duration and comparing the results of antibody screening procedures using specimens that exhibit macroscopically visible rouleaux. Blind titration studies compared untreated and DIDS-treated red cells to evaluate the maintenance of antigen integrity. The use of DIDS-treated red cells for antibody detection and identification was evaluated by comparing the results in donor specimens containing antibodies with those in untreated and DIDS-treated selected panel cells. In addition, 4-percent (wt/vol) dextran in serum was used to induce rouleaux formation as a way of determining the capability of DIDS to resolve ABO serum grouping discrepancies. RESULTS: Complete inhibition of rouleaux formation occurred when reagent red cells were treated by incubation at 37 degrees C for 10 minutes with 150 microliter (approx. 5 drops) of 0.05 mg per mL of DIDS in 0.9-percent NaCl. There were no significant differences in titration scores of untreated and DIDS-treated red cells tested with the 19 antisera used to assess antigen integrity. Antibody identification studies showed that DIDS-treated reagent red cells reacted similarly to untreated reagent red cells. In addition, DIDS resolved dextran-induced ABO serum grouping discrepancies. CONCLUSION: DIDS effectively resolved the serologic problems associated with the presence of rouleaux, without affecting the results of the test system itself. Implementation of this method to inhibit the rouleaux-forming properties of serum and plasma specimens can be useful in serologic testing.

Erythrocyte membrane proteins reactive with IgG (warm-reacting) anti-red blood cell autoantibodies: II. Antibodies coprecipitating band 3 and glycophorin A.

In our initial immunochemical study of the red blood cell (RBC) membrane proteins targeted in 20 cases of warm-antibody autoimmune hemolytic anemia (AHA), RBC eluates of 6 patients mediated immunoprecipitation (IP) of both band 3 and glycophorin A (GPA). This dual IP pattern had previously been observed with murine monoclonal antibodies (MoAbs) against the high frequency blood group antigen, Wrb (Wright), suggesting that the Wrb epitope may depend on a band 3-GPA interaction. Earlier, anti-Wrb had been identified serologically as a prominent non-Rh specificity of AHA autoantibodies. In the present study, 6 autoantibody eluates immunoprecipitating band 3 and GPA from common Wr(b+) RBCs were retested, in parallel with murine anti-Wrb MoAbs, against very rare Wr(a+b-)En(a+)RBCs. One patient's autoantibodies were unreactive with the Wr(b-) RBCs by either IP or indirect antiglobulin test (IAT) and were judged to have "pure" anti-Wrb specificity. Two other patients' autoantibodies displayed both IP and serologic evidence for anti-Wrb as a major component in combination with one or more additional specificities. However, among 3 other patients whose autoantibodies coprecipitated band 3 and GPA, there was no reduction in IP or IAT reactivity with Wr(b-) RBCs in 2 and only slight reduction in the third. We conclude (1) that human anti-Wrb autoantibodies, like their murine monoclonal counterparts, coprecipitate band 3 and GPA from human RBCs; but (2) that not all antibodies with this IP behavior have anti-Wrb serologic specificity, as defined by this donor's Wr(b-) RBCs. The possibility of an additional (non-Wrb) RBC epitope dependent on a band 3-GPA interaction is raised.

The technology assessment and practice guidelines forum. A modified group judgment method.

This article describes a new group-judgment process, modified from the consensus development approach of the U.S. National Institutes of Health. It is called the "forum" method, a shorthand term for "technology assessment and practice guidelines forum." This approach is aimed at (a) describing the current state of knowledge of the technology under study; (b) developing practice guidelines for the use of the technology; and (c) providing information for insurers, consumers, policymakers, and others. A pilot study was conducted focusing on total parenteral nutrition. The validity of the process and of the recommendations and their acceptability were evaluated in a survey of participants and a selected group of nonparticipants. Based on the survey results, the forum method appears to be a valuable method for assessing technologies, defining their clinical role, and developing practice guidelines.

Donath-Landsteiner hemolytic anemia due to an anti-Pr-like biphasic hemolysin.

Anemia, hyperbilirubinemia, and reticulocytosis subsequent to viral infection were present in a 32-year-old woman. The direct antiglobulin test was negative, and no unexpected antibodies were detected in pretransfusion tests. Rosettes of red cells (RBCs) around neutrophils were observed in peripheral blood smears, and a Donath-Landsteiner (D-L) test was positive. However, the patient did not show the classic features of paroxysmal cold hemoglobinuria (PCH). There was no hemoglobinuria, and in vivo hemolysis was not precipitated by cold. The D-L antibody was IgG, but classic anti-P specificity was not apparent. Rather, protease- or neuraminidase-treated RBCs, as well as certain sialic acid deficient RBCs of uncommon MN phenotypes, were not hemolyzed in D-L tests. Further, D-L antibody activity could be inhibited by MN sialoglycoprotein. These data support a diagnosis of chronic D-L hemolytic anemia, caused by an anti-Pr-like biphasic hemolysin.

Further studies on the dependence of some examples of anti-M and anti-N on the presence of red-cell-borne sialic acid.

Previous studies have shown that some examples of anti-M and anti-N fail to agglutinate neuraminidase-treated (NeuNAc-depleted) red cells. This investigation extends those observations and shows that the antibodies fail to bind to such treated red cells. These observations may mean that NeuNAc residues act to orient the protein portion of the MN sialoglycoprotein so that it is recognized by the antibodies. Alternatively, it is possible that NeuNAc residues are an integral part of the antigen defined.

Studies on the blood of an MiV/Mk proposita and her family.

An individual (J-1) was shown to be heterozygous for the MiV and Mk genes. Her red cells typed as M+(weak), N-, S-, s+(strong), U+, Hil+, Wr(a-b-), En(a+weak). Polyacrylamide gel electrophoresis analysis of her red cell membranes revealed absence of PAS-staining bands corresponding to normal MN and Ss sialoglycoprotein (SGP), and presence of a hybrid MNSs SGP [(alpha-delta)MiV] similar but not identical to that reported for an MiV homozygote. However, J-1 cannot be homozygous for MiV since the red cells of two of her children are Hil- and s-, carry only a single dose of M antigen, and have a sialic acid content that is consistent with the presumption that they are Mk heterozygotes. J-1's hybrid MNSs SGP is considered to be gene-fusion product resulting from unequal crossover between a normal alpha M and delta gene, and her red cells lack that portion of the Ena antigen that is resistant to ficin. Her hybrid MNSs SGP differs, therefore, from that reported for the MiV homozygote, which probably arose from unequal crossover between alpha N and delta genes. Further, the red cells of the MiV homozygote carry the ficin-resistant Ena determinant.

Atypical presentation of acute phase, antibody-induced haemolytic anaemia in an infant.

We describe a case of 'warm' antibody-induced haemolytic anaemia (WAIHA) in which marked depression of red cell Rh antigen expression resulted in the patient presenting with severe anaemia but a negative direct antiglobulin test (DAT). The serum contained potent IgG Rh antibodies. Unlike two previously reported cases (Koscielak, 1980; Veer et al. 1981) in which the diagnosis of WAIHA was established before the DAT became negative, this patient presented with negative serological findings during his first episode of anaemia. As a result, the serum antibodies appeared to be allo- not autoimmune in nature and to be unrelated to the patient's anaemia. Confirmation of the autoimmune nature of the Rh antibodies was not possible until nearly 2 years after the first episode of anaemia.

An antibody that recognizes a determinant common to S and s-bearing sialoglycoproteins.

We describe an antibody, made by an individual of the phenotype M+, N+, S+, s+, U+, that reacted only with ficin or papain-treated red blood cells, and that initially appeared to have anti-S specificity. However, further studies revealed that the antibody, which did not have anti-U specificity, recognized a determinant present on S+, s-, U+, and S-, s+, U+, but missing from S-, s-, U-, and S-, s-, U+, red blood cells. The specificity of this antibody is discussed in terms of current knowledge of the structure of the Ss sialoglycoprotein.

Anti-Tm is anti-N polypeptide.

Anti-Tm defines an antigen in the MN blood group system, and 382 Tm + samples were found in tests on 900 random Caucasian, and 500 random Negro bloods. Of the 382 Tm + samples, 373 were also N +, but a further 625 N+ samples were nonreactive with anti-Tm. We have now shown that when the original anti-Tm serum is adsorbed free of anti-T, and is tested against neuraminidase-treated red blood cells, it has anti-N specificity. Further, while anti-Tm cannot be inhibited by sialoglycoprotein (SGP) preparations from untreated N+ red blood cells, it is inhibited by SGP fractions prepared from N+ red blood cells that have been pretreated with neuraminidase. It seems that anti-Tm is directed against a part of the polypeptide backbone of the N SGP.

A new example of anti-LW and further studies on heterogeneity of the system.

A case is reported in which an LW3 woman formed anti-LW. It is shown that the case represents the "genetic" and not the "transient" type of red blood cell LW antigen depletion. Studies have confirmed the quantitative difference of LW antigen on LW3 and LW4 red blood cells and the fact that Rhnull individuals produce the only totally LW-negative red blood cells. The difficulties encountered in the identification of anti-LW, because of the LW3 and LW4 states, are described. It is clear, from this study, that if random donors are typed for LW using anti-LW made by an LW4 indvidual, those who are LW3 will be classed as unremarkable LW-positives.

Evaluation of commercial antiglobulin sera over a two-year period. Part II. Anti-IgG and anti-IgM levels and undesirable contaminating antibodies.

Antiglobulin sera, from nine different manufacturers, have been tested over a two-year period for their ability to detect different nonagglutinating, IgG and IgM blood group antibodies and for the presence of undesirable antibodies that cause the agglutination of nonglobulin coated red blood cells. There are not so many differences in anti-IgG levels among the sera as there are differences in anticomplement levels. Over the two-year period, there have been, in general, increases in the amounts of anti-IgM antibodies in the sera tested. Several of the sera, apparently prepared by dilution of raw rabbit serum and not by adsorption, contain antibodies that cause the agglutination of red blood cells not coated with IgG, IgM, or any of the components of complement.

Evaluation of commercial antiglobulin sera over a two-year period. Part I. Anti-beta 1A, anti-alpha 2D, and anti-beta 1E levels.

Antiglobulin sera from nine different manufacturers have been tested, over a two-year period, for their ability to detect the complement components beta 1A, alpha 2D, and beta 1E. The results demontrate considerable variation in the abilities of sera from different manufacturers to detect these components and indicate that not all sera on the market are suitable reagents for diagnostic use and compatibility tests. The results also show that there is considerable variation between different lots of serum from some of the manufacturers. In general, the anti-complement levels of these reagents have increased during the two-year period of study but not all companies produce suitable reagents for routine use.