The 1989 Comprehensive Blood Bank Survey of the College of American Pathologists.

The 1989 Comprehensive Blood Bank Survey included four additional samples for a total of eight antibody detection and identification challenges. The remainder of the survey was unchanged from prior years. Performance on the graded portions has remained good, with only occasional "problem" samples. For this survey year, the discrepant results were as follows: (1) a D-positive sample not reaching 95% consensus of D typing due to a strong positive direct antiglobulin test; (2) failure of 7% of extent 3 laboratories to identify anti-K in the presence of anti-c; and (3) continued, but lessened "identification" of anti-E, which was not present. The ungraded samples continued to provide educational challenges, and supplemental questions were used to survey current practices.     

Analysis of sentinel node biopsy - a single-institution experience supporting the use of serial sectioning and immunohistochemistry for detection of micrometastases by comparing four different histopathological laboratory protocols

Grabau D, Ryden L, Fernö M & Ingvar C
(2011) Histopathology 59 , 129–138 Analysis of sentinel node biopsy – a single‐institution experience supporting the use of serial sectioning and immunohistochemistry for detection of micrometastases by comparing four different histopathological laboratory protocols Aims: Detecting micrometastases (>0.2 and ≤2 mm/>200 cells) and isolated tumour cells (ITCs; ≤0.2 mm/<200 cells) is important for staging of breast cancer patients. The aim of this study was to systematically compare several laboratory protocols used to detect metastases after initial intraoperative frozen section examination. Methods and results: Four different protocols for the work‐up of sentinel lymph nodes (SLNs) after frozen sectioning were applied in the routine diagnostic process from 2001 to 2009. In addition, team‐work with a limited number of laboratory technicians and pathologists handling SLNs was introduced in 2008. The present study shows that there were, overall, significantly more node‐positive patients in the period when team‐work and intensive step sections including immunohistochemistry (IHC) were used (P = 0.01). This resulted in 13% more patients being found to have ITCs and micrometastases than in a time period when only step sections were performed. No increase in the number of false‐negative frozen sections was seen. Conclusions: Future guidelines for pathological work‐up of sentinel nodes in women with breast cancer might include team‐work and IHC if frozen sections are used intraoperatively.     

Dipeptidyl peptidase 4 is a novel adipokine potentially linking obesity to the metabolic syndrome

OBJECTIVE

Comprehensive proteomic profiling of the human adipocyte secretome identified dipeptidyl peptidase 4 (DPP4) as a novel adipokine. This study assessed the functional implications of the adipokine DPP4 and its association to the metabolic syndrome.

RESEARCH DESIGN AND METHODS

Human adipocytes and skeletal and smooth muscle cells were used to monitor DPP4 release and assess the effects of soluble DPP4 on insulin signaling. In lean and obese subjects, depot-specific expression of DPP4 and its release from adipose tissue explants were determined and correlated to parameters of the metabolic syndrome.

RESULTS

Fully differentiated adipocytes exhibit a substantially higher release of DPP4 compared with preadipocytes or macrophages. Direct addition of DPP4 to fat and skeletal and smooth muscle cells impairs insulin signaling. A fivefold higher level of DPP4 protein expression was seen in visceral compared with subcutaneous fat of obese patients, with no regional difference in lean subjects. DPP4 serum concentrations significantly correlated with adipocyte size. By using adipose tissue explants from lean and obese subjects, we observed a twofold increase in DPP4 release that strongly correlated with adipocyte volume and parameters of the metabolic syndrome and was decreased to the lean level after weight reduction. DPP4 released from adipose tissue correlated positively with an increasing risk score for the metabolic syndrome.

CONCLUSIONS

DPP4 is a novel adipokine that may impair insulin sensitivity in an autocrine and paracrine fashion. Furthermore, DPP4 release strongly correlates with adipocyte size, potentially representing an important source of DPP4 in obesity. Therefore, we suggest that DPP4 may be involved in linking adipose tissue and the metabolic syndrome.Obesity is the hallmark of the metabolic syndrome and represents a major global health problem that frequently associates with the development of chronic diseases, including type 2 diabetes and cardiovascular disease (1). A complex interorgan cross-talk scenario between adipose tissue and other central and peripheral organs underlies the progression of these diseases, with adipose tissue on top of the cross-talk hierarchy (2). This is attributed to the huge diversity of signaling and mediator molecules released from adipose tissue, which is now considered one of the major endocrine organs (3,4). Recent data show that adipokines, which are proteins and peptides released by various adipose tissue cells, create a complex interconnected network of feedback loops (5). Enlargement of adipose tissue leads to dysregulation of adipokine secretion, representing a potential critical pathogenic link among obesity, insulin resistance (IR), and type 2 diabetes (1). Therefore, we conducted a comprehensive proteomic profiling of conditioned media derived from differentiated, primary human adipocytes. This resulted in the identification of novel adipokines, including the exoprotease dipeptidyl peptidase 4 (DPP4).DPP4 is a ubiquitously expressed transmembrane glycoprotein that cleaves N-terminal dipeptides from a variety of substrates, including growth factors and hormones, neuropeptides, and chemokines (6). Two substrates of DPP4, glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP), are released from the intestinal mucosa and responsible for ∼60% of postprandial insulin secretion, the so-called incretin effect (7). Because GLP-1 remains active under hyperglycemic conditions in type 2 diabetes, DPP4 has gained considerable interest as a therapeutic target, and a variety of DPP4-inhibitors that prolong the insulinotropic effect of GLP1 are now in clinical use as antidiabetic drugs (8). Substantial DPP4 activity is also found in plasma and other body fluids because of a soluble form of DPP4 lacking the cytoplasmic tail and the transmembrane region of this protein (9). Both the membrane abundance and the circulating activity of DPP4 have been found to be altered in a variety of neurologic and inflammatory diseases (6). However, although a fraction of soluble DPP4 most likely originates from cells of the immune system (10), the major source of circulating DPP4 and its regulation remain unknown.Furthermore, essentially no data are currently available regarding the potential effects of soluble DPP4 on insulin target tissues, including muscle and fat. In the present investigation, we combined in vitro experiments with two independent clinical studies, aiming to validate DPP4 as a novel adipokine and to characterize the association of DPP4 to different parameters of the metabolic syndrome. We show that 1) DPP4 is a novel adipokine released from differentiated human adipocytes and that it may exert autocrine and paracrine effects leading to IR; 2) DPP4 expression is substantially elevated in visceral fat of obese subjects and that serum DPP4 correlates with adipocyte size and all parameters of the metabolic syndrome; and 3) adipose tissue explants from obese subjects release substantially more DPP4 with a prominent decrease after weight reduction. In light of the well accepted interference of DPP4 with the incretin system, we now suggest that DPP4 may play a role in linking obesity to IR and the metabolic syndrome.     

Reference values of thirty-one frequently used laboratory markers for 75-year-old males and females

Background

We have previously reported reference values for common clinical chemistry tests in healthy 70-year-old males and females. We have now repeated this study 5 years later to establish reference values also at the age of 75. It is important to have adequate reference values for elderly patients as biological markers may change over time, and adequate reference values are essential for correct clinical decisions.

Methods

We have investigated 31 frequently used laboratory markers in 75-year-old males (n = 354) and females (n = 373) without diabetes. The 2.5 and 97.5 percentiles for these markers were calculated according to the recommendations of the International Federation of Clinical Chemistry.

Results

Reference values are reported for 75-year-old males and females for 31 frequently used laboratory markers.

Conclusion

There were minor differences between reference intervals calculated with and without individuals with cardiovascular diseases. Several of the reference intervals differed from Scandinavian reference intervals based on younger individuals (Nordic Reference Interval Project).     

Med1 plays a critical role in the development of tamoxifen resistance

Understanding the molecular pathways that contribute to the development of tamoxifen resistance is a critical research priority as acquired tamoxifen resistance is the principal cause of poor prognosis and death of patients with originally good prognosis hormone-responsive breast tumors. In this report, we provide evidence that Med1, an important subunit of mediator coactivator complex, is spontaneously upregulated during acquired tamoxifen-resistance development potentiating agonist activities of tamoxifen. Phosphorylated Med1 and estrogen receptor (ER) are abundant in tamoxifen-resistant breast cancer cells due to persistent activation of extracellular signal-regulated kinases. Mechanistically, phosphorylated Med1 exhibits nuclear accumulation, increased interaction with ER and higher tamoxifen-induced recruitment to ER-responsive promoters, which is abrogated by inhibition of Med1 phosphorylation. Stable knockdown of Med1 in tamoxifen-resistant cells not only reverses tamoxifen resistance in vitro but also in vivo. Finally, higher expression levels of Med1 in the tumor significantly correlated with tamoxifen resistance in ER-positive breast cancer patients on adjuvant tamoxifen monotherapy. In silico analysis of breast cancer, utilizing published profiling studies showed that Med1 is overexpressed in aggressive subsets. These findings provide what we believe is the first evidence for a critical role for Med1 in tamoxifen resistance and identify this coactivator protein as an essential effector of the tamoxifen-induced breast cancer growth.     

Re-used pacemakers--as safe as new?: A retrospective case-control study

Abstract Re-use of pacemakers is of interest in an era of declininghealth care resources if it is proven safe and without risksto the patients. In order to investigate the safety of re-useof pacemakers we performed a retrospective case-control study.One hundred patients, who received a re-used pacemaker, werematched for date of implantation and mode (AAI;VVI; DDD) to100 others who received a newly manufactured pacemaker and werefollowed for a mean of 32±11 months for complicationsdefined as infections and signs of pacemaker malfunction andpacemaker replacement earlier than anticipated due to batterydepletion. Patients who received re-used pacemakers were significantlyolder than those who received new units (79±9 vs 68±21years;P<0·0001). The number of complications did notdiffer significantly between groups. There were no early replacementsdue to battery depletion in either of the two groups. A cost-benefitanalysis revealed a substantial economical advantage Conclusions The re-use of pacemakers can be carried out withoutincreased risk to the patients provided a proper routine fortechnical control and sterilization is followed. Re-use meanssubstantial savings which possibly could make advanced pacemakertreatment available to all eligible patients irrespective ofage. Whether re-use is feasible with implantable defibrillatorsremains to be determined.     

BALB/c mice, but not C57BL/6 mice immunized with a ΔclpB mutant of Francisella tularensis subspecies tularensis are protected against respiratory challenge with wild-type bacteria: association of protection with post-vaccination and post-challenge immune responses

Francisella tularensis subspecies tularensis is highly virulent for humans especially when it is inhaled. Therefore, it has the potential to be used as a biothreat agent. Vaccines against F. tularensis will need to be approved in accordance with the FDA Animal Rule. This will require identification of robust correlates of protection in experimental animals and the demonstration that similar immune responses are generated in vaccinated humans. Towards this goal, we have developed an experimental live vaccine strain by deleting the gene, clpB, encoding a heat shock protein from virulent subsp. tularensis strain, SCHU S4. SCHU S4ΔclpB administered intradermally protects BALB/c, but not C57BL/6 mice from subsequent respiratory challenge with wildtype SCHU S4. A comparison of post-vaccination and post-challenge immune responses in these two mouse strains shows an association between several antibody and cytokine responses and protection. In particular, elevated IFNγ levels in the skin 2 days after vaccination, sero-conversion to hypothetical membrane protein FTT_1778c, and to 30S ribosomal protein S1 (FTT_0183c) of F. tularensis after 30 days of vaccination, and elevated levels of pulmonary IL-17 on day 7 after respiratory challenge with SCHU S4 were all associated with protection.     

Randomized study for the treatment of adult advanced Hodgkin's disease: mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) versus lomustine, vinblastine, and prednisone

Forty-seven patients with advanced Hodgkin's disease were entered in a prospective, randomized trial comparing MOPP (mechlorethamine, vincristine, procarbazine, and prednisone) with a regimen containing lomustine (CCNU), vinblastine, and prednisone (CCNU-VP). Both groups were comparable for the variables of age, stage, substage (symptoms), histology, prior radiation, and sites of involvement. Seventy-two percent of CCNU-VP-treated patients achieved a pathologically documented complete remission (CR) compared to 41% of the MOPP-treated group. Two additional patients treated with MOPP had remission documented only clinically but have been long-term, disease-free survivors. There was a greater frequency of CR in the patients who had received previous irradiation when compared to patients with no prior irradiation. After a median follow-up of greater than 89 months, there is no statistical difference between the two treatment groups in survival (45% for MOPP and 60% for CCNU-VP). Further, no statistical difference in survival for the two treatment groups was noted when compared by histology, stage, or symptoms. The CCNU-VP combination was better tolerated with significantly less nausea and emesis. The alternative drug regimen of CCNU-VP appears to be as effective as MOPP in producing CR and long-term survival in patients with advanced Hodgkin's disease.     

Disposition of vancomycin in healthy volunteers from oral solution and semi-solid matrix capsules

Gastrointestinal availability of vancomycin from oral solution and semi-solid matrix capsules was determined in volunteers. The capsule produced faecal, plasma and urine levels of the antibiotic which are similar to those obtained with the solution and offers a viable, convenient oral dosage form.     

Continuous ambulatory haemodynamic monitoring with an implantable system: The feasibility of a new technique

Aims This study evaluates the feasibility and safety of a completelyimplantable system for long-term ambulatory monitoring of importanthaemodynamic parameters in patients with severe cardiopulmonarydisease. Methods The design of the implantable monitoring system is similarto a conventional single lead pacemaker. A lead with incorporatedbiosensors for the continuous recording of pressure and oxygensaturation signals is positioned in the right ventricle andconnected to a monitor and memory device subcutaneously implantedlike an ordinary pacemaker can. Results Five patients with implanted haemodynamic monitoringsystems have been followed for from 7 to 16 months. Continuousmeasurements of activity, heart rate, mixed venous oxygen saturationand estimated pulmonary artery diastolic pressure were registeredwith variable resolution during daily living and predefinedprovocations. The memory covered a maximum of 3 weeks at lowresolution. The monitored parameters showed an adequate and significantresponse to various haemodynamic situations. Except for thedemand of recalibration of two oxygen sensors, there were notechnical problems and the quality of data were excellent. Conclusion Long-term ambulatory haemodynamic monitoring is feasibleand potentially useful for the management of patients with severecardiopulmonary disease.