Composition of the additive solution affects red blood cell integrity after photodynamic treatment

BACKGROUND AND OBJECTIVES: Photodynamic treatment is a promising technique for pathogen inactivation of red blood cell concentrates. For protocol optimization, the influence of the composition of the storage solution on the integrity of phototreated red cells was studied. MATERIALS AND METHODS: Red blood cells were resuspended in the storage solutions SAG-M or AS-3 to a haematocrit (Hct) of 30%. After addition of the photosensitizer, 1,9-dimethylmethylene blue (DMMB) (25 microm), the suspensions were illuminated with red light, and potassium leakage and delayed haemolysis were determined. In some experiments, the cells were washed after illumination and resuspended in modified storage solutions. RESULTS: Illumination of red cells in the presence of DMMB resulted in an immediate, light-dose-dependent increase in potassium leakage. The illumination conditions used induced no detectable haemolysis immediately after photodynamic treatment. Potassium leakage was higher when the illumination was performed in AS-3. In contrast, delayed haemolysis, measured after overnight storage, was considerably lower when cells were stored in AS-3. This protection was mainly a result of the presence of citrate in AS-3. In addition, other impermeant solutes protected against haemolysis. CONCLUSIONS: The additive solution strongly influences the integrity of red cells after photodynamic treatment. Whereas the solution in which the cells are illuminated has a small effect on red cell integrity, the main influence of the additive solution is during post-treatment storage. Red cell integrity is best maintained when illumination is performed in SAG-M followed by storage in AS-3. The presence of non-permeant solutes, such as citrate, in the solution used for storage, prevents haemolysis of the phototreated, cation-permeable cells by counterbalancing the osmotic activity of haemoglobin.     

The effect of obesity on clinical outcomes in presumed sepsis: a retrospective cohort study

Sepsis is a major cause of hospital admissions and mortality. Nevertheless, there are significant gaps in our knowledge of the epidemiology of sepsis in obese people, who now represent more than one-third of the population in the United States. The objective of this study was to measure the association between obesity and mortality from presumed sepsis. A retrospective cohort study was used of 1,779 adult inpatients with presumed sepsis at a Tertiary Care Academic Institution from March 1, 2007 to June 30, 2011. Cases of sepsis were identified using a standardized algorithm for sepsis antibiotic treatment. Exposure (i.e., obesity) was defined as a body mass index ≥30 kg/m². Multivariable logistic regression was used to assess the adjusted association between obesity and mortality. Patients with presumed sepsis were of a median age of 60.9 years (interquartile range 49.7–71) and 41.1 % were women. A total of 393 patients died, resulting in a 28-day in-hospital mortality of 22.1 %. In adjusted analysis, obesity was not significantly associated with increased mortality (odds ratio 1.11, 95 % CI 0.85–1.41, P = 0.47). There was also no difference in the in-hospital length of stay (P = 0.45) or maximum percent change in serum creatinine (P = 0.32) between obese and non-obese patients. Finally, there was no difference in the proportion of initial inadequate vancomycin levels (P = 0.1) after presumed sepsis. Obesity was not associated with increased mortality in patients with presumed sepsis. Further research is needed to determine how excess adiposity modulates inflammation from sepsis.     

Functional monocytic myeloid-derived suppressor cells increase in blood but not airways and predict COVID-19 severity

The immunopathology of coronavirus disease 2019 (COVID-19) remains enigmatic, causing immunodysregulation and T cell lymphopenia. Monocytic myeloid-derived suppressor cells (M-MDSCs) are T cell suppressors that expand in inflammatory conditions, but their role in acute respiratory infections remains unclear. We studied the blood and airways of patients with COVID-19 across disease severities at multiple time points. M-MDSC frequencies were elevated in blood but not in nasopharyngeal or endotracheal aspirates of patients with COVID-19 compared with healthy controls. M-MDSCs isolated from patients with COVID-19 suppressed T cell proliferation and IFN-γ production partly via an arginase 1–dependent (Arg-1–dependent) mechanism. Furthermore, patients showed increased Arg-1 and IL-6 plasma levels. Patients with COVID-19 had fewer T cells and downregulated expression of the CD3ζ chain. Ordinal regression showed that early M-MDSC frequency predicted subsequent disease severity. In conclusion, M-MDSCs expanded in the blood of patients with COVID-19, suppressed T cells, and were strongly associated with disease severity, indicating a role for M-MDSCs in the dysregulated COVID-19 immune response.     

Aktueller Stand der Kahnbeinchirurgie

Conservative and various operative treatment options are available for fractures of the scaphoid. Nonunion of the scaphoid requires an operative treatment. Of the patients who underwent surgery for fractures of the scaphoid from 1999 to 2001, 74 were treated with Herbert screw fixation. Nonunion of the scaphoid in 52 cases was treated by iliac crest bone grafting and Herbert screw implantation following resection of the affected bony parts. The cannulated, self-tapping headless bone screw system (cannulated Herbert screw) was used, which allows for easier implantation of the screw. Bony consolidation was achieved in a high proportion of these cases; bony fusion was achieved in all cases of scaphoid fracture. Operative treatment was followed by healing in 47 cases of scaphoid nonunions.     

Zwei tödliche Vergiftungen (Suicid) mit chlorierten Phenoxyessigsäuren (2,4-D und MCPA)

Zusammenfassung Wir konnten zwei tödliche Vergiftungen (Suicide) mit herbicidwirksamen chlorierten Phenoxyessigsäuren (2,4-Dichlorphenoxyessigsäure allein sowie im Gemisch mit 2-Methyl-4-chlorphenoxyessigsäure) beobachten. Unter Hinzunahme der beiden vonNielsen sowieHerbich undMachata beobachteten tödlichen Vergiftungen mit 2,4-D ergeben sich als Initialsymptome Erbrechen und Bewußtlosigkeit. Als auffällig müssen der zunächst ungeschädigte Kreislauf und die in normaler Stärke auslösbaren Reflexe hervorgehoben werden. Die Überlebenszeit kann mehrere Tage betragen. Der Tod trat durch Kreislaufversagen ein. Der klinische Verlauf entspricht damit nicht der in der Literatur beim Tierexperiment beschriebenen Symptomatik einer Myotonie, sondern zeigt, wie schonHerbich undMachata hervorhoben, große Ähnlichkeit mit Vergiftung nach peroraler Aufnahme narkotisch wirkender chlorierter Kohlenwasserstoffe. — Die pathologisch-anatomischen Befunde sind uncharakteristisch. Auffällig ist eine Hyperämie der inneren Organe sowie ein Ödem der Lunge und des Gehirns. In den drei untersuchten Fällen konnten schon makroskopisch an verschiedenen Stellen kleinere Blutaustritte festgestellt werden. — Bei der chemisch-toxikologischen Untersuchung der Körperflüssigkeiten und Organe wurden die unveränderten Wirkstoffe, daneben aber auch diesen verwandte Verbindungen gefunden, bei denen es sich um Metaboliten handeln kann. Es werden Angaben über die Verteilung der Herbicide im Organismus gemacht.Herrn Prof. Dr. Dr. K.Wagner zum 60. Geburtstag gewidmet. Die Arbeit wurde mit Hilfe der Deutschen Forschungsgemeinschaft durchgeführt, wofür wir auch an dieser Stelle unseren besten Dank aussprechen.     

The palmar approach for PIP-arthroplasty according to Simmen: results after 8 years follow-up

Background Alloarthroplasty of the proximal interphalangeal joint is indicated for patients with osteoarthritis, an inflammatory disease of the joint. According to the current literature, implants made of silicone are not inferior to newer implants and the complications are well known. Therefore, focus should be shifted to the operative approach to improve the results.Methods Eleven silicone arthroplasties in 7 patients with arthritis and 35 silicone arthroplasties in 23 patients with osteoarthritis were reviewed after 15.6 months and after 105.3 months. All implants were inserted using the palmar approach according to Simmen. We compared the pre- and postoperative arc of motion, pain, and strength, and present postoperative complications and satisfaction.Results Patients with arthritis showed a gain in range of motion of 36° and patients with osteoarthritis of 39°. No implant failure occurred, and one revision was performed,. Average extension lag over all operated joints of patients was 2.8°. No swan-neck deformity or extensor tendon adhesion was observed. There was no significant difference in the postoperative results between patients with osteoarthritis and arthritis or between first and second follow-up.Conclusion Silicone arthroplasty restores the functionality of proximal interphalangeal joints in patients with osteoarthritis and inflammatory joint disease. Using a palmar approach, the surgeon can reach palmar and dorsal osteophytes. The extensor mechanism stays intact reducing the risk for extensor lag and other complications compared to the dorsal approach. The results do not change significantly between 1 and 8 years postoperatively.