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Using the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) reaction with nitroblue tetrazolium, we provided a detailed investigation of the distribution, dimensional characteristics and morphology of NADPH-d-positive neurons in the three main subdivisions of the human inferior colliculus (IC): central nucleus, pericentral nucleus, and external nucleus. In accordance with their perikaryal diameter, dendritic and axonal morphology, these neurons were categorized as large (averaging up to 45 μm in diameter), medium (20-30 µm), small (13-16 µm) and very small (7-10 µm). Their morphological differences could contribute to varying functionality and processing capacity. Our results support the hypothesis that large and medium NADPH-d-positive cells represent projection neurons, while the small cells correspond to interneurons. Heretofore, the very small NADPH-d-positive neurons have not been described in any species. Their functions-and if they are, indeed, the smallest neurons in the IC of humans-remain to be clarified. Owing to their location, we posit that they are interneurons that connect the large NADPH-d-positive neurons and thereby serve as an anatomical substrate for information exchange and processing before feeding forward to higher brain centers. Our results also suggest that the broad distribution of nitric oxide (NO) synthesis in the human IC is closely tied to the neuromodulatory action of NO on collicular neurotransmitters such as GABA and glutamate, and to calcium-binding proteins such as parvalbumin. A deeper understanding of the relationship between NADPH-d-positive fibers in all IC connections and their co-localization with other neurotransmitters and calcium-binding proteins will assist in better defining the function of NO in the context of its interplay with the cerebral cortex, the sequelae of the aging process and neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

The morphology and distribution of parvalbumin-immunoreactive neurons (PV-ir) were studied in the human claustrum. PV-ir neurons were observed throughout the claustrum, with the highest numbers noted in the central (broadest) portion as compared with the dorsal and ventral aspects. Reaction product was evident in the neuronal perikarya, dendritic processes, and spines. In the majority of these labeled neurons, the cytoplasm was devoid of lipofuscin pigment. Cell bodies varied widely in both shape and size, ranging from oval and small, to multipolar and large. PV-ir neurons were classified into two groups, primarily based on dendritic morphology: spiny neurons with long and straight dendrites, and aspiny neurons with thin and curving dendritic processes. PV-ir fibers were seen throughout the neuropil, with many immuno-positive puncta noted. [ABSTRACT FROM AUTHOR]

We report on the experimental realization of ultra-high quality factor (Q) designs of the L3-type photonic crystal nanocavity. Based on genetic optimization of the positions of few nearby holes, our design drastically improves the performance of the conventional L3 as experimentally confirmed by direct measurement of Q ≃ 2×106 in a silicon-based photonic crystal membrane. Our devices rank among the highest Q/V ratios ever reported in photonic crystal cavities, holding great promise for the realization of integrated photonic platforms based on ultra-high-Q resonators. [ABSTRACT FROM AUTHOR]

Clinical presentation and laboratory data are often too unspecific to distinguish the onset or activity of graft- versus- host disease (GvHD) from infections or toxicity. Antigen-presenting cells such as monocytes/macrophages and dendritic cells are involved in GvHD pathogenesis after allogeneic hematopoietic stem cell transplantation (HSCT). To test whether ferritin, an iron storage marker and macrophage activation-linked acute-phase protein, represents a candidate biomarker for acute or chronic GvHD in pediatric HSCT, we retrospectively evaluated a 2-year follow-up data from 131 eligible consecutive patients with different malignant and nonmalignant diseases who underwent allogeneic HSCT. Thirteen patients (10 %) suffered from acute GvHD II-IV°, 18 (14 %) had limited, and 14 (11 %) had extensive chronic GvHD. In extension of previous studies in adults investigating pre-transplant ferritin, our data show that post-HSCT hyperferritinemia (analyzed on days 0, +30, +60, +100, +180, +360, and +720) was significantly associated with decreased long-term survival ( p < 0.001-0.03) in children and adolescents. Increased ferritin concentrations were associated with number and timing of red blood cell transfusions and toxic or infectious multi-organ failure but did not show significant differences between patients without GvHD and with acute grades II-IV, limited, or extensive chronic GvHD. Thus, our data do not identify ferritin as specifically GvHD-linked biomarker; however, they support the prognostic value of ferritin levels for outcome after HSCT in children. [ABSTRACT FROM AUTHOR]

Copyright of Monatsschrift Kinderheilkunde is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Monatsschrift Kinderheilkunde is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary:Children with multisystem Langerhans cell histiocytosis (LCH) and risk organ involvement who fail to respond to conventional chemotherapy have an extremely poor prognosis. Myeloablative stem cell transplantation (SCT) as a possible salvage approach for these patients has been associated with a high risk of transplant-related mortality. Therefore, allogeneic stem cell transplantation following a reduced-intensity conditioning regimen (RIC-SCT) has recently been performed as an alternative salvage approach. We report on the experience with allogeneic RIC-SCT in nine pediatric high-risk LCH patients. Conditioning regimen included fludarabine in all patients, melphalan in eight patients, total lymphoid irradiation in six patients, total body irradiation in two, antithymocyte globulin in five, and Campath in four patients. RIC-SCT was well tolerated with regard to common procedure-related complications. Two patients died 50 and 69 days after RIC-SCT, respectively. Seven out of the nine patients survived and showed no signs of disease activity (including one with nonengraftment and full autologous hematopoietic recovery) after median follow-up of 390 days post-SCT. Based on this observation, we conclude that RIC-SCT is a feasible procedure with low transplant-related morbidity and mortality and a promising new salvage approach for high-risk LCH patients with resistant risk organ involvement.Bone Marrow Transplantation (2005) 36, 215–225. doi:10.1038/sj.bmt.1705015; published online 6 June 2005 [ABSTRACT FROM AUTHOR]

Great variations exist in the prophylaxis and treatment of GVHD in children undergoing allogeneic stem cell transplantation (SCT). The EBMT Working Party Paediatric Diseases (EBMT-WP PD) and the International BFM Study Group – Subcommittee Bone Marrow Transplantation (IBFM-SG), aimed at evaluating current local standards in the prevention and treatment of GVHD and steps which can be taken to achieve a uniform policy for the individual methods. Several conferences with their members assessed practices which are mainly applied or under investigation in children and identified where additional information is needed. For prevention of GVHD, the majority of the paediatric centres prefer CsA ± MTX. Addition of folinic acid to MTX was considered for reduction of side-effects. During treatment of acute GVHD most centres administer prednisolone and whole blood level-adjusted CsA as medications of first choice. In cases of poor or no response to this therapy, additional immunosuppressive agents such as ATG, mycophenolate-mofetile and tacrolimus are being increasingly used. The treatment of chronic GVHD usually consists of various combinations of prednisolone and CsA. In severe cases, extracorporeal photopheresis, psoralene-UVA (PUVA) and thalidomide are administered. Bone Marrow Transplantation (2000) 26, 405–411. [ABSTRACT FROM AUTHOR]

The occurrence of Langerhans cell histiocytosis (LCH) and acute leukemia in one individual has rarely been observed. Despite few exceptions, two distinct patterns of association appear evident: acute lymphoblastic leukemia preceding LCH and LCH preceding acute nonlymphoblastic leukemia (ANLL). The latency of ANLL after the diagnosis of LCH is suggestive of a therapy-related process. This report describes two new cases in whom ANLL was diagnosed 7 years 8 months and 5 years 8 months after the start of initial treatment of disseminated recurrent LCH. Morphology showed blasts from FAB-type M4/M5 in the first patient, who died due to progression of leukemia. The second patient showed myelodysplastic syndrome (refractory anemia with excess of blasts in transformation; RAEB-t) and is now in remission from leukemia 3 years 11 months after allogeneic bone marrow transplantation. The review of a total of 26 patients with ANLL after LCH suggests that the disease has a poor prognosis and allogeneic BMT seems to be the treatment of choice. [ABSTRACT FROM AUTHOR]

To determine the current approach to stem cell transplantation (SCT) in centres which treat predominantly paediatric patients, a questionnaire was sent to 67 centres known by the EBMT registry to perform SCT mainly in children. Fifty-five centres from 19 countries responded. Forty centres (75%) started their transplantation activities between 1980 and 1992. Median number of transplants/centre was 95 (range 8–400). Median number of transplants/centre/year was 18 (range 5–85). On average, there was one physician responsible for seven SCT/year while one nurse was involved for a median of 1.7 SCT/year. Median four rooms/centre (range 1–17) were available for paediatric SCT. The most common isolation facilities were rooms with high efficiency particulate air filtration (HEPA). Eighty-two percent (45/55) of the centres performed allogeneic as well as autologous SCT, while 5% (three centres) offered exclusively allogeneic SCT and 13% (seven centres) used only autologous stem cell rescue. Stem cell source for allogeneic SCT was bone marrow in 87%, peripheral blood (PB) in 10% and umbilical cord blood in 3%. Donors were HLA matched related in 57%, mismatched related in 13%, and matched unrelated in 30% of allogeneic SCT. PB was the most commonly used stem cell source for autologous SCT (48%), followed by BM (41%) and the two together (11%). Data analysis revealed substantial differences in protective care, stem cell processing and transplantation procedures within the centres, irrespective of the country, centre size and transplant type. [ABSTRACT FROM AUTHOR]