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Background: We assessed the effect of the uniform donor questionnaire (UDQ) on deferral rates in first-time and repeat donors. We focused on the introduced question about unprotected sexual contact with a new partner. Another goal was a stratified comparison of the deferral rates of the donor questionnaire (DQ) and UDQ. Methods: Data on donors and deferrals using the DQ and UDQ were collected at four blood establishments. The comparison included a 2-year period by questionnaire version. For the comparison of the questionnaires, an adjusted multinomial logistic regression was performed. Results: The analysis included 260,848 donations. First-time (FTD) and repeat donations (RD) showed higher deferral rates with the UDQ (FTD +5.4%, RD +1.4%). Deferral due to a new partner was 3.0% in first-time and 0.4% in repeat donors. The majority of these occurred in the youngest age groups. The most frequent deferral criterion was ‘disease' (5.1%). Conclusion: The regression revealed stronger predictors for deferral than the questionnaire version. Especially younger age carried a higher and independent risk for deferral. The additional deferrals of mainly young first-time donors due to a new sexual partner may identify those donors with potential heterosexual risk behavior who would otherwise not be identified.
Since its introduction in 2006, the NOD/scid mouse model has greatly contributed to the understanding of the pathomechanisms of antibody-mediated thrombocytopenia. This progress has however been hampered by inter-laboratory differences. With this work, we make several suggestions to minimise these differences:
We suggest that human platelets (blood group 0) be injected into the mice (age- and sex-matched, 8-16 weeks) via the tail vein. For antibody injection, scientists may choose between intraperitoneal and tail vein injection, each of which has strengths and drawbacks. In case of low antibody titer or low avidity antibodies, preincubation of the platelets with the patient serum prior to injection promotes platelet elimination where standard protocols fail. For subsequent sample preparation, we found that newly-launched ready-to-use kits present a good alternative to classical density gradient centrifugation by reducing man-hours and turnover time without affecting the quality of flow cytometry analysis.
In a second part, we used the revised mouse model to study anti-CD36 mediated thrombocytopenia in vivo. Anti-CD36 antibodies have been suggested as frequent case for FNAIT in Asia. The mechanisms behind this remain partly unclear. After injecting anti-CD36 monoclonal antibody or anti-CD36 patient immunoglobulin into the system, circulating human platelets were rapidly cleared. Interestingly, the polyclonal patient immunoglobulins used were not uniform in their anti-platelet reactivity. On further examination, we found that the anti-CD36 antibodies induce platelet activation and aggregation, which we were able to inhibit by the addition of an Fcγ-receptor blocking agent. This suggests a possible role for Fcγ-receptor in the activation and elimination process.
As our results from the experiments on the role of complement in the elimination process are however ambiguous, further studies are needed. The clinical relevance of anti-CD36 antibody-mediated platelet activation and aggregation for the high abortion rates in affected women has yet to be evaluated.
Background
Signs of an inflammatory process have been described in major depression.
Methods
In a double-blind, randomized study of celecoxib or placebo add-on to reboxetine in 40 depressed patients, celecoxib treatment has beneficial effects. In order to evaluate the tryptophan/kynurenine metabolism and to identify predictors for remission, tryptophan (TRP), kynurenine (KYN), kynurenic acid (KYNA), and quinolinic acid (QUIN) were estimated in the serum of 32 patients before and after treatment and in a group of 20 healthy controls.
Results
KYN levels were significantly lower in patients (p = 0.008), and the QUIN/KYN ratios were significantly higher (p = 0.028). At baseline, the higher KYN/TRP ratio was predictive for remission during celecoxib add-on treatment (p = 0.04) as well as for remission in the overall patient group (p = 0.01). In the placebo group, remitters showed a higher KYNA/QUIN ratio (p = 0.032). In the overall group, remitters showed lower KYNA/KYN (p = 0.035) and QUIN/KYN (p = 0.011) ratios. The lower the formation of downstream metabolites, especially QUIN, the better the treatment outcome.
Conclusion
The high KYN/TRP ratio predicted remission after treatment with celecoxib in this small sample of depressed patients. Eventually, the KYN/TRP ratio might be a marker for those patients, which benefit from an additional anti-inflammatory treatment.
Background: Securing future blood supply is a major issue of transfusion safety. In this prospective 10-year longitudinal study we enrolled all blood donation services and hospitals of the federal state Mecklenburg-Western Pomerania. Methods and Results: From 2005 to 2015 (time period with major demographic effects), whole blood donation numbers declined by 18%. In male donors this paralleled the demographic change, while donation rates of females declined 12.4% more than expected from demography. In parallel, red cell transfusion rates/1,000 population decreased from 2005 to 2015 from 56 to 51 (-8.4%), primarily due to less transfusions in patients >60 years. However, the transfusion demand declined much less than blood donation numbers: -13.5% versus -18%, and the population >65 years (highest transfusion demand) will further increase. The key question is whether the decline in transfusion demand observed over the previous years will further continue, hereby compensating for reduced blood donation numbers due to the demographic change. The population structure of Mecklenburg-Western Pomerania reflects all Eastern German federal states, while the Western German federal states will reach similar ratios of age groups 18-64 years / ≥65 years about 10 years later. Conclusions: Regular monitoring of age- and sex-specific donation and transfusion data is urgently required to allow transfusion services strategic planning for securing future blood supply.