Rapid and Effective Elimination of Myoglobin with CytoSorb® Hemoadsorber in Patients with Severe Rhabdomyolysis

INTRODUCTION

Rhabdomyolysis is characterized by destruction of muscle fibers by various causes and is diagnosed by increased creatine kinase concentrations in the blood. Myoglobin released into the blood may cause acute kidney injury. In this randomized controlled study, we hypothesized that myoglobin elimination would be faster when a hemoadsorber was added to a continuous veno-venous hemodialysis (CVVHD).

METHODS

Four patients in the control group received CVVHD with a high cut-off hemofilter using high blood and dialysate flows for 48 h. Four patients in the CytoSorb group received the same treatment, but in addition, the hemoadsorber CytoSorb® was inserted in front of the hemofilter and replaced once after 24 h. Blood samples were drawn simultaneously before (pre) and after (post) the hemofilter or else the hemoadsorber, after 5 and 30 min, as well as after 2, 4, 8, and 24 h. All measurements were repeated the next day after the hemoadsorber had been renewed in the CytoSorb group. Primary outcome was the area under the curve (AUC) of the relative myoglobin concentrations as percent of baseline. To evaluate the efficacy of myoglobin removal, relative reductions in myoglobin concentrations during one passage through each device at each time point were calculated.

RESULTS

Patients in the CytoSorb group had a significantly lower AUC during the first 24 h (42 ± 10% vs. 63 ± 6%, p = 0.029) as well as during the observation period of 48 h (26 ± 7% vs. 51 ± 12%, p = 0.029). The relative reductions for myoglobin were considerably higher in the CytoSorb group compared to the control group during the first 8 h.

CONCLUSION

Myoglobin concentrations declined considerably faster when CytoSorb was added to a CVVHD. When compared to a high-cut-off hemofilter, efficacy of CytoSorb in myoglobin elimination was much better. Because of saturation after 8-12 h an exchange may be necessary.

Combined antibiotic stewardship and infection control measures to contain the spread of linezolid-resistant Staphylococcus epidermidis in an intensive care unit

Background

The unrestricted use of linezolid has been linked to the emergence of linezolid-resistant Staphylococcus epidermidis (LRSE). We report the effects of combined antibiotic stewardship and infection control measures on the spread of LRSE in an intensive care unit (ICU).

Methods

Microbiological data were reviewed to identify all LRSE detected in clinical samples at an ICU in southwest Germany. Quantitative data on the use of antibiotics with Gram-positive coverage were obtained in defined daily doses (DDD) per 100 patient-days (PD). In addition to infection control measures, an antibiotic stewardship intervention was started in May 2019, focusing on linezolid restriction and promoting vancomycin, wherever needed. We compared data from the pre-intervention period (May 2018–April 2019) to the post-intervention period (May 2019–April 2020). Whole-genome sequencing (WGS) was performed to determine the genetic relatedness of LRSE isolates.

Results

In the pre-intervention period, LRSE were isolated from 31 patients (17 in blood cultures). The average consumption of linezolid and daptomycin decreased from 7.5 DDD/100 PD and 12.3 DDD/100 PD per month in the pre-intervention period to 2.5 DDD/100 PD and 5.7 DDD/100 PD per month in the post-intervention period (p = 0.0022 and 0.0205), respectively. Conversely, vancomycin consumption increased from 0.2 DDD/100 PD per month to 4.7 DDD/100 PD per month (p < 0.0001). In the post-intervention period, LRSE were detected in 6 patients (4 in blood cultures) (p = 0.0065). WGS revealed the predominance of one single clone.

Conclusions

Complementing infection control measures by targeted antibiotic stewardship interventions was beneficial in containing the spread of LRSE in an ICU.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-021-00970-3.

Imaging properties of high aspect ratio absorption gratings for use in preclinical x-ray grating interferometry

X-ray grating interferometry is one among various methods that allow extracting the so-called phase and visibility contrasts in addition to the well-known transmission images. Crucial to achieving a high image quality are the absorption gratings employed. Here, we present an in-depth analysis of how the grating type and lamella heights influence the final images. Benchmarking gratings of two different designs, we show that a frequently used proxy for image quality, a grating's so-called visibility, is insufficient to predict contrast-to-noise ratios (CNRs). Presenting scans from an excised rat lung, we demonstrate that the CNRs obtained for transmission and visibility images anti-correlate. This is explained by the stronger attenuation implied by gratings that are engineered to provide high visibilities by means of an increased lamella height. We show that even the visibility contrast can suffer from this effect when the associated reduced photon flux on the detector is not outweighed by a corresponding gain in visibility. Resulting in an inevitable trade-off between the quality of the two contrasts, the question of how an optimal grating should be designed can hence only be answered in terms of Pareto optimality.

Probing Charges on the Atomic Scale by Means of Atomic Force Microscopy

Kelvin probe force spectroscopy was used to characterize the charge distribution of individual molecules with polar bonds. Whereas this technique represents the charge distribution with moderate resolution for large tip-molecule separations, it fails for short distances. Here, we introduce a novel local force spectroscopy technique which allows one to better disentangle electrostatic from other contributions in the force signal. It enables one to obtain charge-related maps at even closer tip-sample distances, where the lateral resolution is further enhanced. This enhanced resolution allows one to resolve contrast variations along individual polar bonds.

Effect of three-dimensional computed tomography reconstructions on reliability

BACKGROUND

This study evaluated the impact of three-dimensional (3D) volume-rendering computed tomography (CT) reconstructions on the inter- and intraobserver reliability of six commonly used classification systems in the assessment of calcaneal fractures.

METHODS

Four independent observers with different levels of clinical training evaluated 64 fractures according to the classifications of the Orthopaedic Trauma Association (OTA), Essex-Lopresti, Sanders, Crosby, Zwipp, and Regazzoni, using two-dimensional (2D) CT scans with multiplanar reconstructions and 3D volume-rendering reconstructions.

RESULTS

Interobserver reliability was moderate for the OTA, Essex-Lopresti, Sanders, Crosby, and Regazzoni classifications with 2D CT scans and 3D CT reconstructions. The Zwipp classification was poor with 2D CT scans and improved to moderate with 3D reconstructions. Intraobserver reliability with 2D CT scans was good for the Essex-Lopresti classification and moderate for the OTA, Sanders, Crosby, Zwipp, and Regazzoni classifications. After the addition of 3D reconstructions, all classifications showed moderate intraobserver reliability.

CONCLUSION

According to the findings of this study, the additional use of 3D reconstructions is of minor value when used in conjunction with the classifications of the OTA, Sanders, Crosby, Regazzoni, and Essex-Lopresti. If calcaneal fractures are assessed with the Zwipp classification, 3D reconstructions could be used to achieve comparable reproducibility compared to other classifications.

CLINICAL RELEVANCE

3D reconstructions may have other benefits not evaluated in the presented study and may give useful information not captured by current classification systems.

3D blood flow characteristics in the carotid artery bifurcation assessed by flow-sensitive 4D MRI at 3T

To determine three-dimensional (3D) blood flow patterns in the carotid bifurcation, 10 healthy volunteers and nine patients with internal carotid artery (ICA) stenosis > or =50% were examined by flow-sensitive 4D MRI at 3T. Absolute and mean blood velocities, pulsatility index (PI), and resistance index (RI) were measured in the common carotid arteries (CCAs) by duplex sonography (DS) and compared with flow-sensitive 4D MRI. Furthermore, 3D MRI blood flow patterns in the carotid bifurcation of volunteers and patients before and after recanalization were graded by two independent readers. Blood flow velocities measured by MRI were 31-39% lower than in DS. However, PI and RI differed by only 13-16%. Rating of 3D flow characteristics in the ICA revealed consistent patterns for filling and helical flow in volunteers. In patients with ICA stenosis, 3D blood flow visualization was successfully employed to detect markedly altered filling and helical flow patterns (forward-moving spiral flow) in the ICA bulb and to evaluate the effect of revascularization, which restored filling and helical flow. Our results demonstrate the feasibility of flow-sensitive 4D MRI for the quantification and 3D visualization of physiological and pathological flow patterns in the carotid artery bifurcation.

Illness and disability in Danish Chronic Fatigue Syndrome patients at diagnosis and 5-year follow-up

OBJECTIVE

Evaluation of the life impact of Chronic Fatigue Syndrome (CFS) over 5 years.

METHODS

Thirty-three adult patients meeting 1988 and 1994 CDC case criteria answered identical questionnaires at diagnosis and 5 years later, when a retrospective questionnaire was also completed.

RESULTS

Work disability was very high and increased further, social isolation remained high, emotional adjustment improved. There were increased problems with reading and with allergies. Two measures of improvement were used: The relation between these measures was weak. Length of illness, extent of disability and emotional adjustment were poorly related to measures of improvement. Average illness scores were unchanged, but most individuals improved in some ways while worsening or remaining the same in others. Only one participant (3%) neared recovery, one other was substantially better but still severely disabled.

CONCLUSION

CFS patients exhibit severe, long-term functional impairment. Substantial improvement is uncommon, less than 6%. Allergies and aspects of cognition may worsen, emotional adjustment often improves.

Post-liver transplantation lymphoproliferative disorders with and without infusions of donor bone marrow cells

Donor bone marrow cells (DBMC) infusions have been used in an attempt to decrease the untoward effects of immunosuppressive treatment and to improve immunocompetence in the post-liver transplantation (PLT) period. Between March 1987 and July 1996, 558 orthotopic liver transplantations were performed at Jackson Memorial Hospital/University of Miami. Of these, 164 patients (29%) received 10 x 10(8) DBMC/Kg using various schedules. All patients received similar immunosuppressive therapy. After a minimum follow up of 1 year, five cases of Posttransplant Lymphoproliferative Disorder (PTLD) were diagnosed in patients without DMBC (1.3%, 5/394) when compared with none (0/164) in patients who received DBMC (p = 0.15, Fisher). Four patients had malignant lymphoma and one a diffuse atypical lymphoproliferative disorder. All lymphomas were non-Hodgkin's B-cell type, three diffuse large cell lymphoma, and one mixed cell lymphoma. All PTLD tested positive for EBV by in situ hybridization. Lymphomas occurred at 2, 4, 6 months and 4 years PLT. The outcome was poor with one patient diagnosed at autopsy while two patients died a few days after diagnosis. An 8-year-old girl is the only long-term survivor (> 5 years) after a partial response to combination chemotherapy and radiation therapy. The patient with diffuse atypical lymphoproliferative disorder died 3 months later. All patients with PTLD had histologic evidence of liver rejection. Although there is no statistical significant difference between the two groups, a larger cohort of patients will determine the significance of DBMC in preventing PTLD. We believe that the infusion of cytotoxic donor T cells found in the DBMC might suppress EBV-related lymphomagenesis.

Utilization of magnetic resonance imaging in autopsy planning with specimen preservation for thoraco-omphalopagus symmetricus conjoined twins

Conjoined twinning is a rare obstetric event that has fascinated physicians and laypersons alike for centuries. When this event occurs, early diagnosis, close prenatal management, and the proper route of delivery will assure the best possible outcome for mother and affected infants. Magnetic resonance imaging (MRI) is used both as an ancillary technique to the sonography for the antepartum diagnosis and in the preoperative planning for the surgical separation of conjoined twins. This report describes the MRI findings in conjoined twins of the thoraco-omphalopagus symmetricus type, a condition incompatible with extrauterine life. The twins were delivered at 21 weeks gestation. The MRI was used to evaluate the anatomic nature of the internal anomalies. These findings were then used to develop an autopsy approach plan that preserved the external phenotype. After dissection, the specimen was preserved by using polyethylene glycol and ultimately prepared for use as a teaching specimen.

[Current information on the composition and breed distribution of urinary stones in dogs]

5706 canine urinary stones were analyzed by means of infrared spectroscopy from 1984-1996. The stones were sent in together with epidemiologic data (breed, age, sex, localisation of the stones, type of stone removal, stone frequency etc.) by more than 800 veterinarians from Germany, the Netherlands, Austria, and Switzerland. Irrespective of stone type, urinary stones were observed in almost all breeds, but small breeds like dachshound, poodle, terrier, schnauzer, and pekingese have a higher tendency to form stones. With 59.5% struvite is the most frequent stone type, followed by cystine with 15.5%. Cystine stones are becoming less frequent during the observation time, whereas the share of calcium oxalate (14.2%) and ammonium urate (6.0%) stones remains unchanged. The latter stone types are found predominantly in specific breeds. The stone formation appears predominantly at the age of 7. Male dogs form stones twice as often as female dogs. 98% of the stones were located in the lower urinary tract. About 90% of the urinary stones required surgical treatment.

Monoclonal IgA class-switch variants against bacterial surface antigens: molecular forms and transport into murine respiratory secretions

The present study describes a new model for passive immunization of the respiratory tract with IgA in comparison to other isotypes. Monoclonal IgA-isotype-switch variants were isolated from different IgG-producing hybridoma clones specific for surface epitopes of bacterial respiratory tract pathogens. Analysis of the molecular form of the IgA variants revealed the simultaneous production of monomeric, dimeric and higher polymeric IgA by a single-cell line with predominance of the polymeric forms. The specificities of the IgA variants were identical to the parent IgG antibodies as demonstrated by inhibition experiments. The IgA variant antibodies were separated into monomers and polymers by gel filtration. Intravenous injection of the different molecular forms of IgA and of IgG into mice were used to investigate the transport characteristics of IgA into murine upper and lower respiratory tract secretions by the physiological route in comparison to IgG. Polymeric IgA variant, monomeric IgA variant and IgG were detected in immunologically active form in both nasal secretion and bronchoalveolar fluid as evidenced by binding to their antigens in an enzyme-linked immunosorbent assay. The relative contribution of the specific exogenous monoclonal IgA and monoclonal IgG to total IgA and IgG, respectively, was determined in secretions. Comparison of the secretion to serum transport ratios clearly indicates selective transport of polymeric IgA variant into nasal secretions relative to IgG parent antibody. Molecular and functional characteristics of the IgA variants make them ideal for passive mucosal immunization experiments and identification of protective epitopes in mucosal immunity.

Identification of dopamine1A receptors in the rat small intestine

Dopamine receptors have been localized to several tissues outside the central nervous system including the kidney and mesenteric vessels. To determine if there are dopamine1 receptors within the small intestine, homogenates of the antimesenteric halves of the entire jejunum and ileum of adult rats were prepared and competitive inhibition studies and Scatchard analysis were performed at room temperature using 125I-SCH 23982 and SCH 23390. The specific binding of 125I-SCH 23982 to the intestinal tissue homogenates was rapid, saturable with ligand concentration, and reversible. Analysis of the Scatchard plots revealed a single class of receptors with an apparent dissociation constant of 10.77 +/- 2.32 nM and maximum receptor density of 1.37 +/- 0.34 fmole/mg protein. Emulsion autoradiography performed using 125I-SCH 23982 on antimesenteric sections of the rat small intestine revealed that the dopamine1 receptors are located on cells at the base of the intestinal crypts. Two dopamine1 subtypes (D1A and D1B) have been identified by molecular biological techniques. Using a ribonuclease protection assay we found expression of the D1A receptor gene in the small intestinal tissue. These studies are the first to identify, characterize, and localize receptors for the endogenous catecholamine, dopamine, within the rat small intestine and to confirm the expression of the D1A receptor gene.

Ontogeny of DA1 receptor-mediated natriuresis in the rat: in vivo and in vitro correlations

The natriuretic and diuretic effects of dopamine are attenuated in the young. Because dopamine has actions on receptors (e.g., adrenergic, serotonin) other than dopamine, we studied a novel dopamine agonist, pramipexole, which has a selectivity to both DA1 and DA2-receptor subtypes. Intravenous administration of pramipexole resulted in a dose-related (1, 10, and 100 micrograms.kg-1.min-1) increase in urine flow and absolute and fractional sodium excretion and a decrease in mean arterial pressure (MAP) in three groups of rats studied. Pramipexole induced a greater decrease in MAP in 6- to 7- (n = 5) and 9- to 16- (n = 6) than in 3- to 4-wk-old (n = 8) rats; the natriuresis and diuresis were greatest in 12- to 16- and least in 3- to 4-wk-old rats. The renal effects of pramipexole were mainly due to actions at the DA1 receptor, since these effects were completely blocked by the coinfusion of a DA1 antagonist, SKF 83742. To explore further a cause of the attenuated natriuretic effect of pramipexole in the young, we studied the effect of a selective DA1-receptor agonist, fenoldopam, on amiloride-sensitive 22Na+ uptake in renal brush-border membrane vesicles. The 3-s amiloride-sensitive uptake was inhibited (45%) by fenoldopam (5 x 10(-5)M) in 9- to 16- (n = 6) but not in 3- to 4-wk-old (n = 5) rats. These studies suggest that the attenuated natriuretic effect of dopamine in the young is in part due to decreased DA1 action on the brush-border membrane Na(+)-H+ exchanger.

Dopamine inhibits Na(+)-H+ exchanger activity in renal BBMV by stimulation of adenylate cyclase

To determine a renal tubular mechanism for the natriuretic effect of dopamine (DA) and DA-1 agonists, we measured Na(+)-H+ exchange activity (amiloride sensitive) in rat renal cortical brush-border membrane vesicles (BBMV). Renal cortical tissues were preincubated with ligands before BBMV preparation to study Na(+)-H+ exchange activity in the absence of the added ligands that may compete for ion binding sites of the exchanger. DA and DA-1 agonist-inhibited Na(+)-H+ exchange activity was concentration and time dependent. The inhibitory effect was not due to increased permeability, collapse of the proton gradient, or change in vesicle size and did not extend to Na(+)-glucose symport. DA-2 agonists had no effect, whereas alpha-adrenergic agonists increased Na(+)-H+ exchange activity. Kinetic analysis revealed that the DA-1 agonist inhibited Na(+)-H+ exchange activity by a noncompetitive process. 2',5'-Dideoxyadenosine inhibited adenylate cyclase activity and reversed the inhibitory effect of DA-1 agonist on the exchanger. H4, an isoquinoline sulfonamide, which inhibits protein kinase A, also reversed the inhibitory effect of DA-1 agonist on the exchanger. Thus the DA-1 agonist-mediated inhibition of Na(+)-H+ exchange activity in BBMV is a receptor-mediated adenylate cyclase-linked process.

The signal transducer for the dopamine-1 regulated sodium transport in renal cortical brush border membrane vesicles

We have reported the presence of dopamine-1 (DA-1) and dopamine-2 (DA-2) receptors in renal brush border and basolateral membranes. DA-1 agonists stimulate adenylate cyclase (AC) and phospholipase C (PLC) activity in both membranes. Moreover, the ability of a DA-1 agonist (fenoldopam) to stimulate PLC activity is independent of AC activity. A DA-2 agonist (LY171555) by itself was without effect and did not enhance the ability of the DA-1 agonist to stimulate PLC activity. The DA-1 but not DA-2 agonists inhibit Na+/H+ exchange activity in brush border membrane vesicles (BBMV) and Na+/K(+)-ATPase activity in basolateral membranes. However, cAMP inhibits, while protein kinase C (presumably via PLC activity) stimulates, Na+/H+ exchange activity. We therefore determined the effect of DA-1 agonists on Na+/H+ exchange activity when PLC or AC activity was blocked using neomycin or dideoxyadenosine, respectively. The drugs were incubated with minced renal cortex prior to preparation of BBMV by differential centrifugation and MnCl2 precipitation. Enrichment of BBMV was not affected by drug treatment. The Na+/H+ exchange activity was assessed by measuring amiloride (1 mmol/L) sensitive 22Na+ uptake in BBMV (pHi = 5.5, pHo = 7.5, Nai+ = O, Nao+ = 1 mmol/L). Neomycin inhibited DA and DA-1-stimulated PLC activity in BBMV in a concentration dependent manner (10(-6) to 10(-4) mol/L). Neomycin (10(-4) mol/L) completely blocked the ability of DA and DA-1 agonist to stimulate PLC activity but had no consistent effect on DA-1 inhibited Na+/H+ exchange activity. Dideoxyadenosine inhibited DA and DA-1 simulated AC activity without affecting DA-1 stimulated PLC activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Picket-fence porphyrins as potential phototherapeutic agents

The synthetic "picket fence" porphyrin, tetra(o-acetamidophenyl)porphine (TAc), as a biological photosensitizer has been evaluated both in vitro and in vivo in mitochondria from the R3230AC mammary tumor. Studies in vitro, consisting of incubation of mitochondria with TAc at a concentration of 4.0 micrograms/ml followed by photolysis, result in the inhibition of cytochrome c oxidase, proton translocating ATPase, succinate dehydrogenase, and malate dehydrogenase. The diminution in activity of the first three enzymes is approximately 2-fold greater than that seen with Photofrin II under the same conditions. Although TAc exists as four isolable atropisomers, no differences among these different forms were observed in their photosensitized inhibition of mitochondrial enzymes. Administration to tumor-bearing rats of TAc i.p. at a dose of 25 mg/kg did result in accumulation of porphyrin within the mitochondria of the R3230AC tumor as determined by subsequent irradiation of isolated mitochondria. The potential utility of TAc and related porphyrins in cancer phototherapy is discussed.

Closure of osteochondral lesions using chondral fragments and fibrin adhesive

In 75 knee joints of 46 adult rabbits osteochondral defects of 4 mm diameter were placed by a drill reaching the cancellous bone. Twenty-three defects were left untreated, or closed by collagen foam or fibrin adhesive, or a combination of both. Fifty-two defects were closed with very small autologous cartilage fragments and a special fibrin adhesive. The adhesive differed from commercially supplied types by digested alpha chain of fibrinogen for increase in concentration, and by the addition of alpha-2-macroglobulin as protease-inhibitor. In most cases small pieces of collagen foam were added for hemostasis. In the first group of 23 joints observed over up to 40 weeks, no hyaline cartilage was found histologically in any of the defects. In the second group a rapid proliferation of chondrocytes appeared with development of hyaline cartilage with alcianblue-positive matrix. It resembled juvenile cartilage in its histologic appearance and with regard to the induction of ossification. The phenomenon is interpreted as a "second adolescence" of the adult cartilage induced by the rich nutritional and oxygen supply from the cancellous vessels, which resembles the environmental conditions before the forming of subchondral cortical bone at the end of the growth period. This method enabled us to achieve a complete closure of defects by hyaline cartilage on the very level of the surrounding articular surface.

[Angled 1/3-tubular plate for osteosynthesis of dislocated humeral fractures through the collum anatomicum]

Stable osteosynthesis of dislocated fractures of the head of the humerus by lag screws cannot be granted because the avascular head fragment is small. Alternatively the fixation can be performed by means of an angled 1/3-tubular plate with 8 holes. The plate is inserted similar to the condylar plate after preparing a seat with 3 drills of 2 mm ø. The angle-point depends on the diameter of the head fragment. The angle should be approximately 110 degrees. The free part is fixed to the shaft under tension. A successful case of total dislocation for more than one day is demonstrated where no head necrosis occurred.

[The fixation of the flail chest with tension band wires (author's transl)]

A new technique of internal fixation of the flail chest was tested successfully in sheep. After reduction a 0.8 mm wire is passed twice intramedullary across the fracture and twisted under tension with two loops on the external side of the rib. This wire neutralizes bending and rotational forces and produces axial interfragmental compression. Combined with tension band wire fixation of an eventually fractures sternum it produced sufficient stability even in the very thin parasternal part of ribs. No respiratory support was necessary postoperatively. The method is simple and needs no special equipment.

[Development and application of a new polyurethane plastics support bandage (author's transl)]

Experiences with a newly developed plastics support bandage on 1007 patients are reported. A polyurethane hard foam composition developed specially for medical purposes was used, which is created by blending the two components A (polyol) and B (isocyanate). The principle of our support bandage lies in the fact that after being mixed in a 1:1 ratio, the two highly viscous components are packed into a cotton stocking having a high transverse elasticity. After being rolled out to the desired thickness, the stocking is wrapped around the extremity which it is to support, where it hardens out into a polyurethane hard foam composition. By reason of the moisture content of the scoured cotton stocking, a 1 to 2 mm thick layer of foam forms in the contact region and renders any further padding unnecessary. Correspondingly, by using a double chamber stocking, circular bandages have been produced which can be removed, by means of incorporated zip and interengaging hook fasteners. Reclining shells, abduction bandages and body corsets can be made in the same way. The physical properties of the support bandage are illustrated: apart from its low weight, the bandage is particularly advantageous by reason of its high strength, insensitivity to water and ideal permeability to X-rays. The support bandages are easily made up and entail negligible cost.