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131.
BACKGROUND: As COBE Spectra has been replaced in many parts of the world, we describe a new protocol for low‐density lipoprotein (LDL)‐apheresis performed on familial hypercholesterolemia patients for the Spectra Optia platform. METHODS: For all procedures, after administering a bolus of heparin of 2,500 U, 10,000 U of heparin added to a 600 ml ACD‐A bag was used as anticoagulant (AC). In a first phase (A), 16 apheresis procedures with COBE Spectra using an inlet:AC ratio of 25:1 were compared to 18 LDL‐apheresis treatments with Spectra Optia at split Inlet:AC ratios of 16:1/18:1 or 20:1/25:1. Platelet activation and coagulation markers were assessed. In a follow‐up phase (B), 20 procedures on Spectra Optia using an inlet:AC ratio of 20:1 were performed. RESULTS: Although coagulation markers and platelet activation analyzed were similar in both apheresis devices used, COBE Spectra procedures did not show any visual clumping in the sets. Visual analysis of clumping was highest in the Spectra Optia's 20:1/25:1 AC regimen (5/8 procedures). For the lowest Spectra Optia, AC regimen and during the follow‐up phase reversible clump formation in the disposable set was similar (1/10 procedures). Clumping was successfully reversed in all cases by temporarily lowering the inlet:AC ratio to 18:1. Blood cell counts (WBC, Plt, Hct) were similar for both COBE Spectra and Spectra Optia procedures. Spectra Optia had a significantly higher plasma removal efficiency versus COBE Spectra (84% vs.75%, P < .05). No serious adverse events were observed. CONCLUSION: Apheresis procedures on the Spectra Optia system with low‐dose heparin‐citrate anticoagulation are feasible and safe.  相似文献   
132.
The case report that is the subject of this Commentary describes a 27-year-old woman, who, 3 months after a devastating low cervical myelitis, underwent intrathecal mesenchymal stem cell (MSC) infusions. Six hours after the third infusion, she became unconscious, febrile and cerebral MRI showed acute bitemporal and left cerebellar lesions, consistent with an acute disseminated encephalomyelitis. It is likely that this is the first reported patient with neuroinflammatory exacerbation after MSC therapy. This case suggests that, in addition to their malignant potential, autologous MSC expanded in vitro can exhibit immune-activating properties leading to autoimmune exacerbation.  相似文献   
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Unavoidable side reactions of photosynthetic energy conversion can damage the water-splitting photosystem II (PSII) holocomplex embedded in the thylakoid membrane system inside chloroplasts. Plant survival is crucially dependent on an efficient molecular repair of damaged PSII realized by a multistep repair cycle. The PSII repair cycle requires a brisk lateral protein traffic between stacked grana thylakoids and unstacked stroma lamellae that is challenged by the tight stacking and low protein mobility in grana. We demonstrated that high light stress induced two main structural changes that work synergistically to improve the accessibility between damaged PSII in grana and its repair machinery in stroma lamellae: lateral shrinkage of grana diameter and increased protein mobility in grana thylakoids. It follows that high light stress triggers an architectural switch of the thylakoid network that is advantageous for swift protein repair. Studies of the thylakoid kinase mutant stn8 and the double mutant stn7/8 demonstrate the central role of protein phosphorylation for the structural alterations. These findings are based on the elaboration of mathematical tools for analyzing confocal laser-scanning microscopic images to study changes in the sophisticated thylakoid architecture in intact protoplasts.  相似文献   
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Objective

To determine frequencies, interlaboratory reproducibility, clinical ratings, and prognostic implications of neural antibodies in a routine laboratory setting in patients with suspected neuropsychiatric autoimmune conditions.

Methods

Earliest available samples from 10,919 patients were tested for a broad panel of neural antibodies. Sera that reacted with leucine-rich glioma-inactivated protein 1 (LGI1), contactin-associated protein-2 (CASPR2), or the voltage-gated potassium channel (VGKC) complex were retested for LGI1 and CASPR2 antibodies by another laboratory. Physicians in charge of patients with positive antibody results retrospectively reported on clinical, treatment, and outcome parameters.

Results

Positive results were obtained for 576 patients (5.3%). Median disease duration was 6 months (interquartile range 0.6–46 months). In most patients, antibodies were detected both in CSF and serum. However, in 16 (28%) patients with N-methyl-d-aspartate receptor (NMDAR) antibodies, this diagnosis could be made only in cerebrospinal fluid (CSF). The two laboratories agreed largely on LGI1 and CASPR2 antibody diagnoses (κ = 0.95). The clinicians (413 responses, 71.7%) rated two-thirds of the antibody-positive patients as autoimmune. Antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), NMDAR (CSF or high serum titer), γ-aminobutyric acid-B receptor (GABABR), and LGI1 had ≥ 90% positive ratings, whereas antibodies against the glycine receptor, VGKC complex, or otherwise unspecified neuropil had ≤ 40% positive ratings. Of the patients with surface antibodies, 64% improved after ≥ 3 months, mostly with ≥ 1 immunotherapy intervention.

Conclusions

This novel approach starting from routine diagnostics in a dedicated laboratory provides reliable and useful results with therapeutic implications. Counseling should consider clinical presentation, demographic features, and antibody titers of the individual patient.

  相似文献   
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The eight member states (Djibouti, Eritrea, Ethiopia, Kenya, Somalia, South Sudan, Sudan and Uganda) of the Intergovernmental Authority for Development (IGAD) have the largest proportions of cross-border mobile pastoralists and refugees in Africa. Although all IGAD countries have had national HIV/AIDS prevention, care and treatment programmes since the late 1980s, the IGAD Regional HIV & AIDS Partnership Program was (IRAPP) established in 2007 to mitigate the challenges of HIV among neglected pastoral and refugee communities. This article assesses vulnerability of pastoralists and refugee communities to HIV and interventions targeting these groups in the IGAD countries. Outcomes from this study may serve as a baseline for further research and to improve interventions. Published articles were accessed through web searches using PubMed and Google Scholar engines and unpublished documents were collected manually. The search terms were HIV risk behaviour, vulnerability, HIV prevalence and interventions, under the headings pastoralists, refugees, IGAD and north-east Africa for the period 2001–2014. Of the 214 documents reviewed, 78 met the inclusion criteria and were included. Most HIV/AIDS related studies focusing of pastoral communities in IGAD countries were found to be limited in scope and coverage but reveal precarious situations. Sero-prevalence among various pastoral populations ranged from 1% to 21% in Ethiopia, Kenya, Somalia and Uganda and from 1% to 5% among refugees in Sudan, Kenya and Uganda. Socioeconomic, cultural, logistic, infrastructure and programmatic factors were found to contribute to continuing vulnerability to HIV. Interventions need to be further contextualised to the needs of those impoverished populations and integrated into national HIV/AIDS programmes. HIV/AIDS remains a major public health concern among the pastoral and refugee communities of IGAD countries. This calls for IGAD to collaborate with national and international partners in designing and implementing more effective prevention and control programmes. Furthermore, interventions must extend beyond the health sector and improve the livelihood of these populations.  相似文献   
140.
Metastasis in lung cancer is a multifaceted process. In this review, we will dissect the process in several isolated steps such as angiogenesis, hypoxia, circulation, and establishment of a metastatic focus. In reality, several of these processes overlap and occur even simultaneously, but such a presentation would be unreadable. Metastasis requires cell migration toward higher oxygen tension, which is based on changing the structure of the cell (epithelial-mesenchymal transition), orientation within the stroma and stroma interaction, and communication with the immune system to avoid attack. Once in the blood stream, cells have to survive trapping by the coagulation system, to survive shear stress in small blood vessels, and to find the right location for extravasation. Once outside in the metastatic locus, tumor cells have to learn the communication with the “foreign” stroma cells to establish vascular supply and again express molecules, which induce immune tolerance.  相似文献   
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