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The use of lithium (Li) or tin (Sn) as a liquid metal plasma facing component is proposed as a solution to the high power load issue on the divertor region of nuclear fusion reactors. The possibility to use these materials depends on their compatibility with hydrogen plasmas. With the purpose of realizing deuterium retention studies, specimens of pure Sn (99.999% Sn) and Li–Sn alloy (30 at.% Li) were exposed in the ISTTOK edge plasma. Ex situ analysis of the samples was performed by means of ion beam diagnostics. Nuclear reaction analysis (NRA) technique was applied using the D(3He,p)4He reaction to quantify the fuel retention on the samples.In this work the deuterium retention is compared between pure Sn and Li–Sn alloy samples in both liquid and solid states. All the samples were found to have retention ratios smaller than 0.1 at.%. This low retention ratio is expected for pure tin given its high mass and the instability of tin hydrides. However the retention was unexpectedly low for the case of Li–Sn which was thought to be dominated by the lithium fraction in the alloy. These results suggest that tin has a role in the retention mechanism in this material. Keywords: Liquid metals, Plasma-surface interaction, Lithium, Tin, Deuterium retention, Tokamak ISTTOK

This cohort study aimed to characterize the oral microbiome of children with CLP, from two different age groups, and evaluate the effect of supervised or unsupervised toothbrushing on the microbiome of the cleft over time. Swab samples were collected from the cleft area at three different time points (A; no brushing, B; after 15 days and C; after 30 days) and were analyzed using next-generation sequencing to determine the microbial composition and diversity in these time points. Overall, brushing significantly decreased the abundance of the genera Alloprevotella and Leptotrichia in the two age groups examined, and for Alloprevotella this decrease was more evident for children (2–6 years old). In the preteen group (7–12 years old), a significant relative increase of the genus Rothia was observed after brushing. In this study, the systematic brushing over a period of thirty days also resulted in differences at the intra-individual bacterial richness.

A 71-year-old man with Chagas disease and stable angina on minimum exertion underwent coronary computed tomography angiography and cine angiography that revealed heavily calcified multivessel disease involving the left main artery (LM). Due to the degree of calcification, it was decided to perform rotablation. The first-stage percutaneous coronary intervention (PCI) with rotablation was performed on the LM, left anterior descending artery and second diagonal branch without complications. Almost 30 days later he returned for right coronary artery (RCA) PCI. The proposed strategy was rotational atherectomy in the posterior descending artery (PDA) and right posterolateral artery (RPLA) with a 1.5 mm burr, followed by implantation of two drug-eluting stents (DES). Through right femoral artery access the RPLA lesion was ablated with success. As there were no signs of dissection and TIMI 3 flow was maintained, the 0.009″ RotaWire was repositioned to cross the PDA lesion and debulking of the lesion was performed. After two attempts we succeeded in crossing the lesion with the 1.5 mm burr, however entrapment of the burr ensued. The system was pulled back until the guiding catheter penetrated deep into the RCA, and attempts were made to release the Rotablator by moving it forward and backward, but the burr did not even spin. The contralateral femoral artery was therefore punctured and a 6F JR guiding catheter was inserted, in order to move a guidewire and small angioplasty balloon tangentially to the burr, but without success. Finally we advanced the guidewire using the ‘knuckle’ technique, taking advantage of the kinking of the distal portion of the PT2 guidewire, performing a subintimal dissection and re-entry, and could then easily cross the balloon, inflate it and release the trapped burr. Through the 6F system, two programmed and one bailout DES were successfully implanted in the PDA, RPLA and RCA, obtaining final TIMI 3 flow without complications. Resumo: Um homem de 71 anos, diabético, com doença de Chagas e com angina estável de mínimos esforços, efetuou angiotomografia coronária e cineangiocoronariografia revelando doença multiarterial severamente calcificada envolvendo o tronco da coronária esquerda (TCE). Devido ao grau de calcificação, a aterectomia rotacional foi considerada. Na primeira etapa a angioplastia coronária (ATC) com aterectomia rotacional (Rotablator) foi realizada no TCE, artéria descendente anterior e segundo ramo diagonal sem intercorrências. Quase 30 dias depois retornou para ATC da artéria coronária direita (CD). A estratégia proposta foi a aterectomia rotacional nos ramos DP e VPD com oliva de 1,5 mm, seguida de implante de dois stents farmacológicos (DES). Por acesso femoral direito 7F, a lesão do VPD foi ablacionada com sucesso. Como não havia sinais de disseção e manutenção de fluxo TIMI III, reposicionamos o “Rotawire 0,009” atravessando a lesão do DP e procedemos à ablação da lesão. Depois de duas tentativas conseguimos cruzar a lesão; no entanto, houve o aprisionamento da oliva. O sistema foi tracionado sem sucesso, levando o catéter guia a penetrar fundo na CD, com posterior disseção. Foi tentada a retirada do “Rotablator” com movimentos de avanço e recuo, mas a oliva sequer girou. A decisão então foi puncionarmos a artéria femoral contralateral inserindo um cateter guia JR6F e tentarmos avançar uma corda guia e balão de fino calibre tangencialmente à oliva. Não obtivemos sucesso até que finalmente avançamos o fio-guia com a técnica de Knuckle aproveitando a dobra da extremidade distal do fio-guia PT2 e pudemos facilmente atravessar o balão, insuflar e libertar o aprisionamento da oliva. Através do catéter guia 6F, os dois stents programados (DP e VPD) e um adicional (CD) foram implantados com sucesso obtendo-se fluxo final TIMI III, sem intercorrências clínicas.

Biological, and particularly antimicrobial, activities have been demonstrated for the essential oil of propolis samples worlwide, yet their mutagenic effects remain unknown. To correlate antimicrobial effects with mutagenic risks, the present study evaluated the antifungal and antibacterial activities of the essential oil obtained from brown propolis collected from the Cerrado biome in Midwest Brazil (EOP), testing it against nine pathogenic microorganisms. Evaluation of mutagenic potential was based on the somatic mutation and recombination test (SMART) performed on wing cells of standard (ST) and high-bioactivation (HB) crosses of Drosophila melanogaster. EOP was extracted by hydrodistillation, and sesquiterpenes were characterized by GC–MS as its major constituents. The crude oil proved active against Cryptococcus neoformans and Enterococcus faecalis, as did two of its major constituents, spathulenol and (E)-nerolidol – the latter being also active against Staphylococcus aureus – isolated using chromatographic procedures. No significant increase in the number of somatic mutations was observed in the offspring of ST or HB crosses – the latter exhibiting enhanced levels of metabolizing enzymes of the cytochrome P450 type – treated with 0.05%, 0.1%, and 0.2% EOP. These findings revealed no mutagenic activity of EOP, even when tested against the HB strain, and demonstrated that its antimicrobial activities are not associated with DNA damage induction (investigated with SMART), suggesting the potential of EOP as a natural preservative.

Machado-Joseph disease (MJD) or Spinocerebellar ataxia type 3 (SCA3) is a progressive neurodegenerative disorder that affects movement coordination leading to a premature death. Despite several efforts, no disease-modifying treatment is yet available for this disease. Previous studies pinpointed the modulation of serotonergic signaling, through pharmacological inhibition of the serotonin transporter SERT, as a promising therapeutic approach for MJD/SCA3. Here, we describe the 5-HT1A receptor as a novel therapeutic target in MJD, using a C. elegans model of ATXN3 proteotoxicity. Chronic and acute administration of befiradol (also known as NLX-112), a highly specific 5-HT1A agonist, rescued motor function and suppressed mutant ATXN3 aggregation. This action required the 5-HT1A receptor orthologue in the nematode, SER-4. Tandospirone, a clinically tested 5-HT1A receptor partial agonist, showed a limited impact on animals' motor dysfunction on acute administration and a broader receptor activation profile upon chronic treatment, its effect depending on 5-HT1A but also on the 5-HT6/SER-5 and 5-HT7/SER-7 receptors. Our results support high potency and specificity of befiradol for activation of 5-HT1A/SER-4 receptors and highlight the contribution of the auto- and hetero-receptor function to the therapeutic outcome in this MJD model. Our study deepens the understanding of serotonergic signaling modulation in the suppression of ATXN3 proteotoxicity and suggests that a potent and selective 5-HT1A receptor agonist such as befiradol could constitute a promising therapeutic agent for MJD.

Several snake species possess, in their circulating blood, endogenous PLA2 inhibitors (sbPLIs) with the primary function of natural protection against toxic enzymes from homologous and heterologous venoms. Among the three structural classes of sbPLIs – named α, β, and γ − the β class (sbβPLIs) is the least known with only four identified sequences, so far. The last class of inhibitors encompass molecules with leucine rich repeats (LRRs) motifs containing repeating amino acid segments. In the present study, we identified and characterized putative sbβPLIs from the liver and venom glands of six Latin American pit vipers belonging to Bothrops and Crotalus genera. The inhibitor from Crotalus durissus terrificus snakes (CdtsbβPLI) was chosen as a reference for the construction of the first in silico structural model for this class of inhibitors, using molecular modeling and molecular dynamics simulations. Detailed analyses of the electrostatic surface of the CdtsbβPLI model and protein-protein docking with crotoxin B from homologous venoms predict the interacting surface between these proteins. Keywords: Phospholipase A2 inhibitor, Beta inhibitors, Phospholipase A2, Viperidae, Snake venom gland, Snake liver, Pit viper

Abstract: Autoimmune cytopenia (AIC) in children may be associated with positive antinuclear antibodies (ANA) and may progress to systemic lupus erythematosus (SLE). We evaluated the risk of progression to SLE of childhood-onset ANA-associated AIC. In the French national prospective OBS'CEREVANCE cohort, the long-term outcome of children with ANA-associated AIC (ANA titer ≥1/160) and a subgroup of children who developed SLE were described. ANA were positive in 355 of 1803 (20%) children with AIC. With a median follow-up of 5.8 (range, 0.1-29.6) years, 79 of 355 (22%) patients developed SLE at a median age of 14.5 (1.1-21.4) years; 20% of chronic immune thrombocytopenic purpura, 19% of autoimmune hemolytic anemia, and 45% of Evans syndrome. None of the patients with ANA-negative test developed SLE. Severe manifestations of SLE were observed in 21 patients, and 2 patients died. In multivariate analysis including patients with positive ANA within the first 3 months after AIC diagnosis, age >10 years at AIC diagnosis (relative risk [RR], 3.67; 95% confidence interval [CI], 1.18-11.4; P = .024) and ANA titer >1/160 (RR, 5.28; 95% CI, 1.20-23.17; P = .027) were associated with the occurrence of SLE after AIC diagnosis. ANA-associated AIC is a risk factor for progression to SLE, especially in children with an initial ANA titer >1/160 and an age >10 years at AIC diagnosis. ANA screening should be recommended in children with AIC, and patients with ANA should be monitored long-term for SLE, with special attention to the transition period. This trial was registered at www.ClinicalTrials.gov as #NCT05937828., (© 2024 American Society of Hematology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.)

Next-generation sequencing is becoming increasingly important for the diagnosis, risk stratification, and management of patients with established or suspected myeloid malignancies. These tests are being incorporated into clinical practice guidelines and many genetic alterations now constitute disease classification criteria. However, the reimbursement for these tests is uncertain. This study analyzed the clinical impact, ordering practices, prior authorization, and reimbursement outcomes of 505 samples from 477 patients sequenced with a 50-gene myeloid next-generation sequencing panel or a 15-gene myeloproliferative neoplasm subpanel. Overall, 98% (496 of 505) of tests provided clinically useful data. Eighty-nine percent of test results, including negative findings, informed or clarified potential diagnoses, 94% of results informed potential prognoses, and 19% of tests identified a potential therapeutic target. Sequencing results helped risk-stratify patients whose bone marrow biopsy specimens were inconclusive for dysplasia, monitor genetic evolution associated with disease progression, and delineate patients with mutation-defined diagnoses. Despite the clinical value, prior authorization from commercial payors or managed government payors was approved for less than half (45%) of requests. Only 51% of all cases were reimbursed, with lack of medical necessity frequently cited as a reason for denial. This study demonstrates the existence of a substantial gap between clinical utility and payor policies on test reimbursement., Competing Interests: Disclosure Statement S.J.H. has received honoraria from AstraZeneca and institutional research funding from Bristol Myers Squibb. G.B. has received honoraria from Blueprint Medicines., (Copyright © 2024 Association for Molecular Pathology and American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Splenectomy is effective in ∼70% to 80% of pediatric chronic immune thrombocytopenia (cITP) cases, and few data exist about it in autoimmune hemolytic anemia (AIHA) and Evans syndrome (ES). Because of the irreversibility of the procedure and the lack of predictions regarding long-term outcomes, the decision to undertake splenectomy is difficult in children. We report here factors associated with splenectomy outcomes from the OBS'CEREVANCE cohort, which prospectively includes French children with autoimmune cytopenia (AIC) since 2004. The primary outcome was failure-free survival (FFS), defined as the time from splenectomy to the initiation of a second-line treatment (other than steroids and intravenous immunoglobulins) or death. We included 161 patients (cITP, n = 120; AIHA, n = 19; ES, n = 22) with a median (minimum-maximum) follow-up of 6.8 years (1.0-33.3) after splenectomy. AIC subtype was not associated with FFS. We found that immunopathological manifestations (IMs) were strongly associated with unfavorable outcomes. Diagnosis of an IM before splenectomy was associated with a lower FFS (hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.21-0.72, P = .003, adjusted for AIC subtype). Diagnosis of an IM at any timepoint during follow-up was associated with an even lower FFS (HR, 0.22; 95% CI, 0.12-0.39; P = 2.8 × 10-7, adjusted for AIC subtype) as well as with higher risk of recurrent or severe bacterial infections and thrombosis. In conclusion, our results support the search for associated IMs when considering a splenectomy to refine the risk-benefit ratio. After the procedure, monitoring IMs helps to identify patients with higher risk of unfavorable outcomes., (© 2022 by The American Society of Hematology.)

Targetable NTRK gene fusions can be detected across tumor types using methodologies such as pan-TRK IHC, DNA or RNA NGS testing, or FISH. Challenges for implementation of clinical testing for NTRK fusions may arise due to the range in NTRK fusion prevalence across tumors, endogenous levels of TRK expression in tissues, and the large number of potential fusion partners. In this study, we examined our experience evaluating driver mutation negative lung, urothelial or cholangiocarcinoma cases, in addition to cases with positive, equivocal, or weak staining by pan-TRK IHC for NTRK fusions. 63/127 (49.6%) of these cases were positive for pan-TRK IHC, of which 71.4% showed weak or focal staining, potentially due to physiologic or non-specific TRK expression. Of these 127 cases, 4 harbored a NTRK fusion (1 fusion was seen in two separate samples from the same patient) as confirmed by RNA fusion panel testing. Pan-TRK IHC was positive in 1 case with TPM3-NTRK1 fusion, equivocal in 1 case with GOLGA4-NTRK3 fusion, and negative in 2 samples with ADAM19-NTRK3 fusion. Our findings show that we were able to successfully identify NTRK fusions that resulted in targeted therapy. However, our results suggest limited sensitivity of pan-TRK IHC for NTRK3 fusions, and that the reduced specificity for pan-TRK IHC in tumors with physiologic or non-specific TRK expression, results in false positive samples that require confirmatory testing by RNA based NGS., (Copyright © 2022. Published by Elsevier Inc.)

The early detection of breast cancer is a vital factor when it comes to improving cure and recovery rates in patients. Among such early detection factors, one finds thermography, an imaging technique that demonstrates good potential as an early detection method. Convolutional neural networks (CNNs) are widely used in image classification tasks, but finding good hyperparameters and architectures for these is not a simple task. In this study, we use two bio-inspired optimization techniques, genetic algorithm and particle swarm optimization to find good hyperparameters and architectures for the fully connected layers of three state of the art CNNs: VGG-16, ResNet-50 and DenseNet-201. Through use of optimization techniques, we obtained F1-score results above 0.90 for all three networks, an improvement from 0.66 of the F1-score to 0.92 of the F1-score for the VGG-16. Moreover, we were also able to improve the ResNet-50 from 0.83 of the F1-score to 0.90 of the F1-score for the test data, when compared to previously published studies., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This multi-institutional study was undertaken to evaluate interrater reliability of the 2017 Association for Molecular Pathology/American Society of Clinical Oncology/College of American Pathologists guidelines for interpretation and reporting of oncology sequence variants and to assess current practices and perceptions surrounding these guidelines. Fifty-one variants were distributed to 20 participants from 10 institutions for classification using the new guidelines. Agreement was assessed using chance-corrected agreement (Cohen κ). κ was 0.35. To evaluate if data sharing could help resolve disagreements, a summary of variant classifications and additional information about each variant were distributed to all participants. κ improved to 0.7 after the original classifications were revised. Participants were invited to take a web-based survey regarding their perceptions of the guidelines. Only 20% (n = 3) of the survey respondents had prior experience with the guidelines in clinical practice. The main perceived barriers to guideline implementation included the complexity of the guidelines, discordance between clinical actionability and pathobiologic relevance, lack of familiarity with the new classifications, and uncertainty when applying criteria to potential germline variants. This study demonstrates noteworthy discordances between pathologists for variant classification in solid tumors when using the 2017 Association for Molecular Pathology/American Society of Clinical Oncology/College of American Pathologists guidelines. These findings highlight potential areas for clarification/refinement before mainstream clinical adoption., (Copyright © 2020 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.)

Purpose: Kabuki syndrome (KS) (OMIM 147920 and 300867) is a rare genetic disorder characterized by specific facial features, intellectual disability, and various malformations. Immunopathological manifestations seem prevalent and increase the morbimortality. To assess the frequency and severity of the manifestations, we measured the prevalence of immunopathological manifestations as well as genotype-phenotype correlations in KS individuals from a registry., Methods: Data were for 177 KS individuals with KDM6A or KMT2D pathogenic variants. Questionnaires to clinicians were used to assess the presence of immunodeficiency and autoimmune diseases both on a clinical and biological basis., Results: Overall, 44.1% (78/177) and 58.2% (46/79) of KS individuals exhibited infection susceptibility and hypogammaglobulinemia, respectively; 13.6% (24/177) had autoimmune disease (AID; 25.6% [11/43] in adults), 5.6% (10/177) with ≥2 AID manifestations. The most frequent AID manifestations were immune thrombocytopenic purpura (7.3% [13/177]) and autoimmune hemolytic anemia (4.0% [7/177]). Among nonhematological manifestations, vitiligo was frequent. Immune thrombocytopenic purpura was frequent with missense versus other types of variants (p = 0.027)., Conclusion: The high prevalence of immunopathological manifestations in KS demonstrates the importance of systematic screening and efficient preventive management of these treatable and sometimes life-threatening conditions.

Evans syndrome (ES) is a rare severe autoimmune disorder characterized by the combination of autoimmune hemolytic anemia and immune thrombocytopenia. In most cases, the underlying cause is unknown. We sought to identify genetic defects in pediatric ES (pES), based on a hypothesis of strong genetic determinism. In a national, prospective cohort of 203 patients with early-onset ES (median [range] age at last follow-up: 16.3 years ([1.2-41.0 years]) initiated in 2004, 80 nonselected consecutive individuals underwent genetic testing. The clinical data were analyzed as a function of the genetic findings. Fifty-two patients (65%) received a genetic diagnosis (the M+ group): 49 carried germline mutations and 3 carried somatic variants. Thirty-two (40%) had pathogenic mutations in 1 of 9 genes known to be involved in primary immunodeficiencies ( TNFRSF6 , CTLA4 , STAT3 , PIK3CD , CBL , ADAR1 , LRBA , RAG1 , and KRAS ), whereas 20 patients (25%) carried probable pathogenic variants in 16 genes that had not previously been reported in the context of autoimmune disease. Lastly, no genetic abnormalities were found in the remaining 28 patients (35%, the M- group). The M+ group displayed more severe disease than the M- group, with a greater frequency of additional immunopathologic manifestations and a greater median number of lines of treatment. Six patients (all from the M+ group) died during the study. In conclusion, pES was potentially genetically determined in at least 65% of cases. Systematic, wide-ranging genetic screening should be offered in pES; the genetic findings have prognostic significance and may guide the choice of a targeted treatment., (© 2019 by The American Society of Hematology.)

Weak magnetic stress detection is an important issue in oil-gas pipeline internal detection area. In order to verify the characteristics of weak magnetic stress internal detection signals, we built herein a magneto-mechanics equivalent model having a balanced magnetic field. First, we calculated the relationship between the stress and the weak magnetic signals; consequently, the analysis propagation laws of the weak magnetic signals with non-magnetic saturation were pointed out. Finally, the theoretical model was validated by a systematic experimental research. The analytical results show that a one-to-one linear link between the weak magnetic signals and the stress concentration is clear. Instead, the change of the weak magnetic signals with the liftoff is nonlinear, therefore we are proposing the Boltzmann liftoff correction factor whose degree of adaptability of the equivalent model can reach the value of 94%. It is possible to note that when the liftoff is in the approximate linear stage, the relevance ratio and the recognition rate of the magneto-mechanics curve show a high-quality. This conclusion is important in the engineering field for the set of the liftoff., (Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.)

Head and neck squamous cell carcinoma (HNSCC) can be divided into two different clinical entities based on their association with high-risk subtypes of human papilloma virus (HPV16 and HPV18). Dissimilarities in prognosis and molecular profiles have attracted much attention in recent years, in part because of increasing rates of HPV infection in HNSCC; however, the underlying mechanisms and detailed genetic profiles that set these tumors apart are still elusive. To elucidate oncogenic pathways in HNSCC with and without HPV infection, we used targeted next-generation sequencing to interrogate single-nucleotide polymorphisms (SNPs) in 50 cancer-related genes. We detected SNPs in 25 of these genes from HNSCC tissue specimens with and without HPV infection. In 5 of the 25 genes, variant patterns were similar regardless of HPV infection status. A greater number of sequence variants in genes from the tyrosine kinase receptors and their associated pathways were preferentially present in HPV(+) specimens. SNPs in genes related to tumor-suppressor functions were more prevalent in HPV(-) HNSCC specimens. The observations may help to elucidate mechanisms involved in the molecular pathogenesis of two clinically diverse subclasses of HNSCC. Over-representation of SNPs in either HPV(+) or HPV(-) HNSCC is another indicator of potentially actionable sequence variants for targeted therapy., (Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Objectives: This study aimed to assess the impact of the duration of organ dysfunction on the outcome of patients with severe sepsis or septic shock., Methods: Clinical data were collected from hospital charts of patients with severe sepsis and septic shock admitted to a mixed intensive care unit from November 2003 to February 2004. The duration of organ dysfunction prior to diagnosis was correlated with mortality. Results were considered significant if p<0.05., Results: Fifty-six patients were enrolled. Mean age was 55.6+/-20.7 years, mean APACHE II score was 20.6+/-6.9, and mean SOFA score was 7.9+/-3.7. Thirty-six patients (64.3%) had septic shock. The mean duration of organ dysfunction was 1.9+/-1.9 days. Within the univariate analysis, the variables correlated with hospital mortality were: age (p=0.015), APACHE II (p=0.008), onset outside the intensive care unit (p=0.05), blood glucose control (p=0.05) and duration of organ dysfunction (p=0.0004). In the multivariate analysis, only a duration of organ dysfunction persisting longer than 48 hours correlated with mortality (p=0.004, OR: 8.73 (2.37-32.14)), whereas the APACHE II score remained only a slightly significant factor (p=0.049, OR: 1.11 (1.00-1.23)). Patients who received therapeutic interventions within the first 48 hours after the onset of organ dysfunction exhibited lower mortality (32.1% vs. 82.1%, p=0.0001)., Conclusions: These findings suggest that the diagnosis of organ dysfunction is not being made in a timely manner. The time elapsed between the onset of organ dysfunction and initiation of therapeutic intervention can be quite long, and this represents an important determinant of survival in cases of severe sepsis and septic shock.

Plant pathogenesis-related (PR) proteins of class 10 (PR-10) are small and cytosolic. The main feature of their three-dimensional structure is a large cavity between a seven-stranded antiparallel beta-sheet and a long C-terminal alpha-helix. Although PR-10 proteins are abundant in plants, their physiological role remains unknown. Recent data have indicated ligand binding as their possible biological function. The article describes the structure of a complex between a classic PR-10 protein (yellow lupine LlPR-10.2B) and the plant hormone, trans-zeatin. Previously, trans-zeatin binding has been reported in a structurally related cytokinin-specific binding protein, which has a distant sequence relation with classic PR-10 proteins. In the present 1.35 A resolution crystallographic model, three perfectly ordered zeatin molecules are found in the binding cavity of the protein. The fact that three zeatin molecules are bound by the protein when only a fourfold molar excess of the ligand was used indicates an unusual type of affinity for this ligand and suggests that LlPR-10.2B, and perhaps other PR-10 proteins as well, acts as a reservoir of cytokinin molecules in the aqueous environment of the cell.

The neurokinin-1 (NK-1) receptor interacts with peptides that belong to the tachykinin family. NK-1 is inducible in bone marrow (BM) stroma. In neural cells, its expression is high to constitutive. Screening of three cDNA libraries indicated that this different in NK-1 expression in neural and BM cells could not be explained by differences in the cDNA sequence. Analyses the 5' flanking sequence in BM stroma and three neural cell lines indicated that sequence +1/+358 relative to the transcription start (TS) site could account for the differences in NK-1 expression. Particular cytokines could reverse the repressive effects of region +1/+358 in BM stroma. The effects of NF-kappa B and cAMP activators were studied in stromal cells using a dominant negative inhibitor of NF-kappa B (I kappa B) or a repressor of CRE activators (ICERII gamma). The results showed that their effects of these transcription factors depended on the stimulating cytokine. This study provides insight into the tissue-specific differences in the expression of the NK-1 gene.

As NZB mice age, approximately 90% of the 12-month-old mice possess an expansion of malignant B-1 (CD5+ B cells) cells with many similarities to the human lymphoproliferative disease, chronic lymphocytic leukemia. Malignant B-1 cells derived from NZB mice produce significantly higher levels of IL-10 mRNA and protein than normal B-1 or B cells. IL-10 may act as an autocrine growth factor for the expansion of B-1 cells. In this report, the infrequent animals which survived 18 months of age or longer were studied and compared to NZB mice at 12-14 months of age. Analysis of lymphoid subpopulations in the spleen and peritoneal cavity indicated that long-lived NZB mice had an expansion of CD8+ T cells rather than the typical B-1 expansion observed in the majority of NZB animals at 12 months of age. We established a CD8+ T cell clone from long-lived NZB mice which was cytotoxic for malignant B-1 cells of NZB origin both in vivo and in vitro. Analysis of the regulatory mechanisms preventing the development of genetically programmed age-dependent CLL in the murine system may elucidate possible avenues for therapeutic intervention in CLL.