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Los brackets son aparatos de corrección empleados en casos de problemas dentales como apiñamiento, mordidas abiertas, entre otros. Con el pasar del tiempo, los brackets han ido avanzando en el diseño y materiales empleados para su elaboración, pasando desde brackets convencionales con gomas y ligaduras metálicas hasta brackets autoligados, cuyo sistema incorporado le permite sujetarse al arco. En este sentido, el objetivo de esta revisión va dirigido a comparar el tiempo de tratamiento entre los brackets de autoligado versus la ortodoncia convencional. Para ello, se seleccionaron 50 artículos de diversas bases de datos, considerando que los mismos estuvieran relacionados con el tiempo de tratamiento. Tanto los brackets convencionales como los autoligados poseen sus propias características y funciones, sin embargo, hasta ahora no se ha demostrado la efectividad de un tratamiento sobre otro en cuanto al tiempo. Es importante resaltar el tiempo de tratamiento va en dependencia del tipo de mal oclusión y la cooperación del paciente.

Se buscó identificar las habilidades que debe tener un buen docente desde la percepción de futuros profesores. Se analizaron 1047 respuestas de estudiantes de pedagogía al ingresar a la universidad los años 2021 y 2022. Los resultados arrojan que los futuros profesores consideran el desarrollo de la ética y responsabilidad, la empatía y el manejo del comportamiento de los estudiantes en la sala de clases como las habilidades más importantes a desarrollar en la universidad. Se concluye que tener habilidades para interactuar es más importante que el dominio conceptual para ser buen profesor según este grupo de futuros docentes.

COQ7 encodes a hydroxylase responsible for the penultimate step of coenzyme Q10 (CoQ10) biosynthesis in mitochondria. CoQ10 is essential for multiple cellular functions, including mitochondrial oxidative phosphorylation, lipid metabolism, and reactive oxygen species homeostasis. Mutations in COQ7 have been previously associated with primary coenzyme Q10 deficiency, a clinically heterogeneous multisystemic mitochondrial disorder. We identified COQ7 biallelic variants in nine families diagnosed with distal hereditary motor neuropathy (dHMN) with upper neuron involvement, expending the clinical phenotype associated with defects in this gene. A recurrent p.Met1? change was identified in five families from Brazil with evidence of a founder effect. Fibroblasts isolated from patients revealed a substantial depletion of COQ7 protein levels, indicating protein instability leading to loss of enzyme function. HPLC assay showed that fibroblasts from patients had reduced levels of CoQ10, and abnormal accumulation of the biosynthetic precursor DMQ10. Accordingly, fibroblasts from patients displayed significantly decreased oxygen consumption rates in patients, suggesting mitochondrial respiration deficiency. iPSC-derived motor neurons from patient fibroblasts showed significantly increased levels of extracellular neurofilament light protein, indicating axonal degeneration. Our findings indicate a molecular pathway involving CoQ10 biosynthesis deficiency and mitochondrial dysfunction in patients with dHMN. Further studies will be important to evaluate the potential benefits of CoQ10 supplementation in the clinical outcome of the disease.

Lipid analysis at the molecular species level represents a valuable opportunity for clinical applications due to the essential roles that lipids play in metabolic health. However, a comprehensive and high-throughput lipid profiling remains challenging given the lipid structural complexity and exceptional diversity. Herein, we present an 'omic-scale targeted LC-MS/MS approach for the straightforward and high-throughput quantification of a broad panel of complex lipid species across 26 lipid (sub)classes. The workflow involves an automated single-step extraction with 2-propanol, followed by lipid analysis using hydrophilic interaction liquid chromatography in a dual-column setup coupled to tandem mass spectrometry with data acquisition in the timed selective reaction monitoring mode (12 min total run time). The analysis pipeline consists of an initial screen of 1903 lipid species, followed by high-throughput quantification of robustly detected species. Lipid quantification is achieved by a single-point calibration with 75 isotopically labeled standards representative of different lipid classes, covering lipid species with diverse acyl/alkyl chain lengths and unsaturation degrees. When applied to human plasma, 795 lipid species were measured with median intra-and inter-day precisions of 8.5 and 10.9%, respectively, evaluated within a single and across multiple batches. The concentration ranges measured in NIST plasma were in accordance with the consensus intervals determined in previous ring-trials. Finally, to benchmark our workflow, we characterized NIST plasma materials with different clinical and ethnic backgrounds and analyzed a sub-set of sera (n = 81) from a clinically healthy elderly population. Our quantitative lipidomic platform allowed for a clear distinction between different NIST materials and revealed the sex-specificity of the serum lipidome, highlighting numerous statistically significant sex differences.

Lipid analysis at the molecular species level represents a valuable opportunity for clinical applications due to the essential roles that lipids play in metabolic health. However, a comprehensive and high-throughput lipid profiling remains challenging given the lipid structural complexity and exceptional diversity. Herein, we present an ‘omic-scale targeted LC-MS/MS approach for the straightforward and high-throughput quantification of a broad panel of complex lipid species across 21 lipid (sub)classes. The workflow involves an automated single-step extraction with 2-propanol, followed by lipid analysis using Hydrophilic Interaction Liquid Chromatography (HILIC) in a dual-column setup coupled to tandem mass spectrometry with data acquisition in timed-selective reaction monitoring (t-SRM) mode (12 min total run time). The analysis pipeline consists of an initial screen of 1922 lipid species, followed by high-throughput quantification of robustly detected species. Lipid quantification is achieved by a single-point calibration with 75 isotopically labeled standards representative of different lipid classes, covering lipid species with diverse acyl/alkyl chain lengths and unsaturation degrees. When applied to human plasma, 807 lipid species were measured with median intra- and inter-day precision of 9.5 % and 13.6 %, respectively, evaluated within a single and across multiple batches. The concentration ranges measured in NIST plasma were in accordance with the consensus intervals determined in previous ring-trials. Finally, to benchmark our workflow, we characterized NIST plasma materials with different clinical and ethnic backgrounds and analyzed a sub-set of sera (n=81) from a clinically healthy elderly population. Our quantitative lipidomic platform allowed for a clear distinction between different NIST materials and revealed the sex-specificity of the serum lipidome, highlighting numerous statistically significant sex differences.

Rationale: Reperfusion injury accounts for up to half of myocardial infarct size, and meaningful clinical therapies targeting it do not exist. We have reported previously that autophagy is reduced during reperfusion and that HDAC (histone deacetylase) inhibition enhances cardiomyocyte autophagy and blunts ischemia/reperfusion (I/R) injury when administered at the time of reperfusion. However, whether inducing autophagy per se, as opposed to other effects triggered by HDAC inhibition, is sufficient to protect against reperfusion injury is not clear. Objective: We set out to test whether augmentation of autophagy using a specific autophagy-inducing peptide, TB (Tat-Beclin), protects the myocardium through reduction of reactive oxygen species (ROS) during reperfusion injury. Methods and Results: Eight- to 12-week-old, WT (wild type) C57BL6 mice and tamoxifen-inducible cardiomyocyte-specific ATG7 KO (ATG7 knockout) mice (to test the dependency on autophagy) were randomized into 2 groups: exposed to a control TS (Tat-scrambled) peptide or a TB peptide. Each group was subjected to I/R surgery (45-minute coronary ligation, 24-hour reperfusion). Infarct size, systolic function, autophagic flux, and ROS were assayed. Cultured neonatal rat ventricular myocytes were exposed to TB during simulated I/R injury. ATG7 knockdown by small interfering RNA in neonatal rat ventricular myocytes was used to evaluate the role of autophagy. TB treatment at reperfusion reduced infarct size by 20% (absolute reduction; 50% relative reduction) and improved contractile function. Improvement correlated with increased autophagic flux in the border zone with less oxidative stress. ATG7 KO mice did not manifest TB-promoted cardioprotection during I/R. In neonatal rat ventricular myocytes subjected to I/R, TB reduced cell death by 41% and reduced I/R-induced ROS generation. Conversely, ATG7 knockdown in neonatal rat ventricular myocytes abolished these beneficial effects of TB on cell death and ROS reduction. Conclusions: Induction of autophagy at the time of reperfusion is sufficient to mitigate myocardial reperfusion injury by reducing ROS and cell death. Maintenance of appropriate autophagic flux may emerge as a viable clinical therapy to reduce reperfusion injury in acute myocardial infarction.

TPS1126 Background: Only a subset of patients with metastatic triple-negative breast cancer demonstrate response to currently approved PD-1 immune checkpoint blockade, and few have durable responses. Antigen presentation defects may be a reason for this low response because deficiency of antigen-presenting DC1 dendritic cells is associated with poor anti-tumor immunity. CD40 agonists are a class of agents that activate antigen presenting cells including dendritic cells and B cells and also repolarize macrophages. Flt3 ligand is a growth factor that increases dendritic cells. In line with this, we recently demonstrated in pre-clinical models that the combination of liposomal-doxorubicin chemotherapy, a CD40 agonist, and a Flt3 ligand improves outcomes of breast cancer compared to alternate combinations. Methods: This is a single arm phase I pilot study of liposomal-doxorubicin, CDX-1140 (CD40 agonist), and CDX-301 (Flt3 ligand) combination therapy in patients with metastatic or unresectable locally advanced metastatic triple-negative breast cancer. Patients will be randomized to 3 lead-in arms (triplet therapy, doublet immunotherapy only, liposomal-doxorubicin only) prior to receiving full triplet therapy with fresh tissue biopsies before and after the lead-in treatment. CDX-301 will be discontinued after 2 cycles; liposomal-doxorubicin and CDX-1140 will be continued until disease progression or clinically limiting toxicities. Primary endpoint is determination of a recommended phase 2 dose based on treatment-related adverse events including dose-limiting toxicities. Secondary endpoints include anti-tumor immune response after triplet therapy, after immunotherapy alone, and after liposomal-doxorubicin alone; median progression-free survival, overall response rate, duration of response, and clinical benefit rate. Key eligibility criteria are unresectable stage III or stage IV triple-negative breast cancer (ER ≤10%, PR ≤10%, HER2/neu negative), 1st to 3rd line metastatic treatment setting (1st line patients need to be PD-L1 negative by 22C3 assay), measurable disease by RECIST 1.1 criteria, consent for pre-treatment and on-treatment biopsies of amenable soft tissue tumor lesions, no prior treatment with an anti-CD40 antibody or a Flt3 ligand, no anthracycline treatment in the metastatic setting, no prior progression while on anthracycline-based therapy or within 6 months of completing neoadjuvant chemotherapy, and no history of non-infectious pneumonitis or current pneumonitis. This trial will enroll up to 45 patients across multiple sites. Clinical trial information: NCT05029999.

Journal of neurochemistry : JNC 156(6), 802-818 (2021). doi:10.1111/jnc.15233, Published by Wiley-Blackwell, Oxford

Expanding metabolome coverage to include complex lipids and polar metabolites is essential in the generation of well-founded hypotheses in biological assays. Traditionally, lipid extraction is performed by liquid-liquid extraction using either methyl-tert-butyl ether (MTBE) or chloroform, and polar metabolite extraction using methanol. Here, we evaluated the performance of single-step sample preparation methods for simultaneous extraction of the complex lipidome and polar metabolome from human plasma. The method performance was evaluated using high-coverage Hydrophilic Interaction Liquid Chromatography-ESI coupled to tandem mass spectrometry (HILIC-ESI-MS/MS) methodology targeting a panel of 1159 lipids and 374 polar metabolites. The criteria used for method evaluation comprised protein precipitation efficiency, and relative MS signal abundance and repeatability of detectable lipid and polar metabolites in human plasma. Among the tested methods, the isopropanol (IPA) and 1-butanol:methanol (BUME) mixtures were selected as the best compromises for the simultaneous extraction of complex lipids and polar metabolites, allowing for the detection of 584 lipid species and 116 polar metabolites. The extraction with IPA showed the greatest reproducibility with the highest number of lipid species detected with the coefficient of variation (CV) &lt, 30%. Besides this difference, both IPA and BUME allowed for the high-throughput extraction and reproducible measurement of a large panel of complex lipids and polar metabolites, thus warranting their application in large-scale human population studies.

Introduction: Postpartum stroke is a rare and unpredictable complication of pregnancy. Infections have been associated with an increased risk of stroke in young people. We hypothesized that infections diagnosed during delivery hospitalizations would be associated with an increased risk of postpartum readmission for stroke. Methods: We conducted a weighted analysis of the 2013 Healthcare Cost and Utilization Project National Readmissions Database to assess the relationship between infection during a delivery hospitalization and 30-day readmission for a stroke. Delivery hospitalization, stroke and infections, and comorbidities were identified using ICD-9 diagnosis codes. We created survey design logistic regression models to calculate crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between infections and 30-day readmission for stroke, adjusting for disease severity, length of delivery hospitalization, and age. Results: There were 3,512,350 delivery hospitalizations, with 79,656 subsequent readmissions, including 225 for stroke. Compared with all other women who delivered, women with infections during the delivery hospitalization had higher odds of readmission for postpartum stroke (adjusted OR 5.7, 95%CI 2.4-13.6). When compared to women who were readmitted for non-stroke reasons, women who were readmitted for stroke had higher odds of an infection during the delivery hospitalization (adjusted OR 3.5, 95%CI 1.9-6.5). The effect of infection on postpartum stroke risk was present in women both with and without hypertensive disorders of pregnancy (Table). Conclusion: Infections diagnosed during delivery hospitalizations were associated with an increased risk of readmission for postpartum stroke. Women who are diagnosed with infections during delivery admissions should be educated on signs and symptoms of stroke and when to seek emergency medical attention.

Breast cancer (BC) is a highly heterogeneous disease associated with metabolic reprogramming. The shifts in the metabolome caused by BC still lack data from Latin populations of Hispanic origin. In this pilot study, metabolomic and lipidomic approaches were performed to establish a plasma metabolic fingerprint of Colombian Hispanic women with BC. Data from 1H-NMR, GC-MS and LC-MS were combined and compared. Statistics showed discrimination between breast cancer and healthy subjects on all analytical platforms. The differentiating metabolites were involved in glycerolipid, glycerophospholipid, amino acid and fatty acid metabolism. This study demonstrates the usefulness of multiplatform approaches in metabolic/lipid fingerprinting studies to broaden the outlook of possible shifts in metabolism. Our findings propose relevant plasma metabolites that could contribute to a better understanding of underlying metabolic shifts driven by BC in women of Colombian Hispanic origin. Particularly, the understanding of the up-regulation of long chain fatty acyl carnitines and the down-regulation of cyclic phosphatidic acid (cPA). In addition, the mapped metabolic signatures in breast cancer were similar but not identical to those reported for non-Hispanic women, despite racial differences.

Background: Reperfusion injury accounts for a significant portion of myocardial damage in acute coronary syndromes. Autophagy, a process of cell catabolism, plays a vital role in the heart’s response to stress. We have reported that re-induction of ischemia/reperfusion (I/R)-suppressed cardiomyocyte autophagy with histone deacetylase (HDAC) inhibitors affords significant cardioprotection. However, as HDACs govern many processes and may have off-target effects, we set out to modulate autophagy in a manner independent of HDAC activity. Here, we hypothesized that induction of autophagy with a novel agent, Tat-Beclin, at the time of reperfusion, will reduce I/R injury and rescue cardiac function. Methods: Wild type and ATG7 (protein required for autophagic flux) knockout mice were randomized among 3 treatment groups prior to surgical I/R injury [45 min LAD artery ligation; 24h reperfusion]: vehicle control (VC), Tat-Scrambled (TS), or Tat-Beclin (TB). Each agent was delivered at coronary reperfusion. To define molecular mechanisms, cultured adult and neonatal rat ventricular cardiomyocytes (ARVMs/NRVMs) were subjected to simulated I/R. Results: Induction of cardiomyocyte autophagy at reperfusion reduced infarct size 20.1% (±6.3%, n=23, p Conclusion: Direct induction of cardiomyocyte autophagy reduces infarct size and declines in contractile function. Autophagy rescues I/R injury in part through reduction of oxidative stress. Critically, this cardioprotection was observed when intervention occurred at the time of reperfusion, the clinically relevant context.

The MS blastomere produces one third of the body-wall muscles (BWMs) in the C. elegans embryo. MS-derived BWMs require two distinct cell-cell interactions, the first inhibitory and the second, two cell cycles later, required to overcome this inhibition. The inductive interaction is not required if the inhibitory signal is absent. Although the Notch receptor GLP-1 was implicated in both interactions, the molecular nature of the two signals was unknown. We now show that zygotically-expressed MOM-2 (Wnt) is responsible for both interactions. Both the inhibiting and the activating interactions require precise spatiotemporal expression of zygotic MOM-2, which is dependent upon two distinct Notch signals. In a Notch mutant defective only in the inductive interaction, MS-derived BWMs can be restored by preventing zygotic MOM-2 expression, which removes the inhibitory signal. Our results suggest that the inhibitory interaction ensures the differential lineage specification of MS and its sister blastomere, whereas the inductive interaction promotes the expression of muscle-specifying genes by modulating TCF and β-catenin levels. These results highlight the complexity of cell fate specification by cell-cell interactions in a rapidly dividing embryo.

Background The purpose of this study was to determine the association between posttraumatic stress disorder (PTSD), diagnosed prospectively during pregnancy, and the risk of delivering a low birth weight ( Methods Pregnant women were recruited from obstetrics clinics and screened for major and minor depressive disorder, panic disorder, PTSD, and substance use. Current episodes of PTSD were diagnosed according to the MINI International Neuropsychiatric Interview, and pregnancy outcomes were abstracted from hospital records. Results Among the 1100 women included in analysis, 31 (3%) were in episode for PTSD during pregnancy. Substance use in pregnancy, panic disorder, major and minor depressive disorder, and prior preterm delivery were significantly associated with a diagnosis of PTSD. Preterm delivery was non-significantly higher in pregnant women with (16.1%) compared to those without (7.0%) PTSD (OR = 2.82, 95% C.I. 0.95, 8.38). Low birth weight (LBW) was present in 6.5% of women and was not significantly associated with a diagnosis of PTSD in pregnancy after adjusting for potential confounders. However, LBW was significantly associated with minor depressive disorder (OR = 1.82, 95% C.I. 1.01, 3.29). Limitations There was a low prevalence of PTSD in this cohort, resulting in limited power. Conclusions These data suggest a possible association between PTSD and preterm delivery. Coupled with the association found between LBW and a depressive disorder, these results support the utility of screening for mental health disorders in pregnancy.

The determination of the origin of coffee beans by NMR fingerprinting has been shown promising and classification has been reported for samples of different countries and continents. Here we show that this technique can be extended and applied to discriminate coffee samples from one country against all others, including its closest neighbors. Very high classification rates are reported using a large number of spectra (>300) acquired over a two-year period. As original aspects it can be highlighted that this study was performed in fully automatic mode and with non-deuterated coffee extracts. This is achieved using a series of experiments to procure a robust suppression of the solvent peaks. As is, the method represents a cost effective opportunity for countries to protect their national productions.

La contribución al conocimiento científico de los casos clínico/planes de cuidados es escasa, sin embargo constituyen una herramienta docente muy importante. En los últimos años, la Enfermería está creando espacios comunes que ayudan a la correcta toma de decisiones basadas en sesiones clínicas y en el cuestionamiento de casos clínicos. Por ello, se considera pertinente realizar este estudio con el objetivo de evaluar la calidad metodológica de este tipo de diseños publicados en la revista ENE en el periodo 2007-2013. Se tuvieron en cuenta dos herramientas de evaluación metodológicas, una para casos clínicos (30 ítems) y otra para planes de cuidados (15 ítems). Se identificaron 30 artículos a estudio (13 casos clínicos y 17 planes de cuidados). Como resultados principales destacan que las puntuaciones en los planes de cuidados fueron más elevadas que en los casos clínicos. The contribution to scientific knowledge of clinical cases and care plans is limited; however, theyconstitute an important teaching tool. In recent years, the nursing profession has embraced the use of clinical sessions and cases to help improve clinical decision-making. Therefore, it is considered appropriate to conduct this study in order to assess the methodological quality of the experiences published in ENE during the 2007-2013 period. Two methodological assessment tools were used, for clinical cases (30 items) and care plans (15 items). Thirty papers were identified, including 13 clinical cases and 17 care plans. The main results suggest that scores on care plans were higher than in clinical cases.

Se dice que el gran Eduardo Galeano (Montevideo, Uruguay, 1940) consideraba que “cuando los libros estan de veras vivos, respiran; y uno se los pone al oido y les siente la respiracion y sus palabras son contagiosas, peligrosamente, carinosamente contagiosas”. Seria adecuado, y quizas indudable, sugerir que lo mismo pudiera decirse de las publicaciones cientificas en general y enfermeras en particular, considerando su razon ultima de ser la difusion mas efectiva posible de ideas, experiencias, y actividades de investigacion al resto de nuestra comunidad cientifica y de practica.

El auge de la investigación enfermera en nuestro entorno crea la necesidad de realizar estudios bibliométricos que la visibilicen. El objetivo principal de este estudio consiste en analizar la producción científica en la revista ENE durante el periodo 2009-2013. Se trata de un diseño bibliométrico donde se incluyeron 75 artículos con resultados de investigación, los cuales fueron analizados por pares. Los resultados más relevantes son que gran parte de la producción son resultados de investigaciones de ambos abordajes metodológicos (cuantitativos/cualitativos), predominantemente de origen español, en su mayoría de Canarias, y con una participación internacional de ámbito iberoamericano. Existe escasa colaboración entre instituciones, CCAA y países. Hay un cambio de tendencias en las áreas temáticas donde los Cuidados Básicos y Fundamentos de Enfermería han pasado a encabezar la lista. The growth of nursing research in our setting demands bibliometric studies to highlight its impact. This study analyzed research papers published in ENE during the period 2009-2013, using a bibliometric approach. 75 research articles were analysed and results compared with a previous publication. Main results include an equal proportion of quantitative and qualitative designs; a majority of projects carried out in Spain, and the Canary Islands. International projects were developed in Latin America. There was limited institutional, regional and country collaboration. Finally, there was a shift in the topics published, now headed by basic care and fundamentals of nursing projects.

In the canonical Wnt pathway, signaling results in the stabilization and increased levels of β-catenin in responding cells. β-catenin then enters the nucleus, functioning as a coactivator for the Wnt effector, TCF/LEF protein. In the absence of Wnt signaling, TCF is complexed with corepressors, together repressing Wnt target genes. In C. elegans, Wnt signaling specifies the E blastomere to become the endoderm precursor. Activation of endoderm genes in E requires not only an increase in β-catenin level, but a concomitant decrease in the nuclear level of POP-1, the sole C. elegans TCF. A decrease in nuclear POP-1 levels requires Wnt-induced phosphorylation of POP-1 and 14-3-3 protein-mediated nuclear export. Nuclear POP-1 levels remain high in the sister cell of E, MS, where POP-1 represses the expression of endoderm genes. Here we express three vertebrate TCF proteins (human TCF4, mouse LEF1 and Xenopus TCF3) in C. elegans embryos and compare their localization, repression and activation functions to POP-1. All three TCFs are localized to the nucleus in C. elegans embryos, but none undergoes Wnt-induced nuclear export. Although unable to undergo Wnt-induced nuclear export, human TCF4, but not mouse LEF1 or Xenopus TCF3, can repress endoderm genes in MS, in a manner very similar to POP-1. This repressive activity requires that human TCF4 recognizes specific promoter sequences upstream of endoderm genes and interacts with C. elegans corepressors. Domain swapping identified two regions of POP-1 that are sufficient to confer nuclear asymmetry to human TCF4 when swapped with its corresponding domains. Despite undergoing Wnt-induced nuclear export, the human TCF4/POP-1 chimeric protein continues to function as a repressor for endoderm genes in E, a result we attribute to the inability of hTCF4 to bind to C. elegans β-catenin. Our results reveal a higher degree of species specificity among TCF proteins for coactivator interactions than for corepressor interactions, and uncover a basic difference between how POP-1 and human TCF4 steady state nuclear levels are regulated.

Standard histochemical analysis of cells and tissues generally involves procedures that utilize a relatively small number of probes such as dyes, and generally requires hours or days to process. Our laboratory has developed a novel method for histochemical surveys of cell surface properties that utilizes a large number of probes (derivatized agarose beads) and takes seconds or minutes to accomplish. In this study, 4 human cell lines (CCL-255 (LS123) human colon cancer cells that are non-tumorigenic in nude mice; CRL-1459 (CCD-18CO) human colon endothelial cells that are non-malignant; CCL-220 (COLO 320DM) human colon cancer cells that are tumorigenic in nude mice; and HTB-171 (NCI H446) human lung carcinoma cells) were tested for their ability to bind to agarose beads derivatized with 51 different molecules. There were statistically significant differences in binding of the 4 cell types to all of the 51 types of beads, but 15 types of beads showed dramatic differences in binding to one or more of the 4 cell types. For example, only HTB-171 (NCI H446) bound to p-aminophenyl-beta-D-glucopyranoside-derivatized beads and only CCL-220 (COLO 320DM) bound to L-tyrosine-derivatized beads. The specificity of cell-bead binding was examined by performing assays in the presence or absence of exogenously added compounds in hapten-type of inhibition experiments. This assay, that utilizes large numbers of novel probes, may help in the development of new libraries of surface properties of specific cell types, with differing degrees of malignancy, that at this time could not be developed by using other available technologies.