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Lamb-Shaffer Syndrome (LSS; OMIM #616803; ORPHA #313892; ORPHA #313884) is an infrequent genetic disorder that affects multiple aspects of human development especially those related to the development of the nervous system. LSS is caused by variants in the SOX5 gene. At the molecular level, SOX5 gene encodes for a transcription factor containing a High Mobility Group (HMG) DNA-Binding domain with relevant functions in brain development in different vertebrate species. Clinical features of Lamb-Shaffer syndrome may include intellectual disability, delayed speech and language development, attention deficits, hyperactivity, autism spectrum disorder, visual problems and seizures. Additionally, patients with the syndrome may present distinct facial dimorphism such as a wide mouth with full lips, small chin, broad nasal bridge, and deep-set eyes. Other physical features that have been reported in some patients include short stature, scoliosis, and joint hypermobility. Here, we report the clinical and molecular characterization of a Spanish LSS cohort of new 20 patients and review all the patients published so far which amount for 111 patients. The most frequent features included developmental delay, intellectual disability, visual problems, poor speech development and facial dysmorphic features. Strikingly, pain insensitivity and hypermetropia seems to be more frequent than previously reported, based on the frequency seen in the Spanish cohort. Eighty-three variants have been reported so far, single nucleotide variants (SNV) and copy number variants represent 47% and 53%, respectively, from the total of variants reported. Similarly to previous reports, the majority of the SNVs variants of the novel patients reported herein fall in the HMG domain of the protein. However, new variants, affecting other functional domains, were also detected. In conclusion, LLS is a rare genetic disorder mostly characterized by a wide range of developmental and neurological symptoms. Early diagnosis would allow to start of care programs, clinical follow up, prospective studies and appropriate genetic counseling, to promote clinical and social improvement to have profound lifelong benefits for patients and their families. Further research is needed to better understand the underlying mechanisms of the syndrome related to SOX5 haploinsufficiency., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: The COVID-19 pandemic emerged in a context that lacked adequate prevention, preparedness, and response (PPR) activities, and global, regional, and national leadership. South American countries were among world's hardest hit by the pandemic, accounting for 10.1% of total cases and 20.1% of global deaths., Methods: This study explores how pandemic PPR were affected by political, socioeconomic, and health system contexts as well as how PPR may have shaped pandemic outcomes in Argentina, Brazil, Colombia, and Peru. We then identify lessons learned and advance an agenda for improving PPR capacity at regional and national levels. We do this through a mixed-methods sequential explanatory study in four South American countries based on structured interviews and focus groups with elite policy makers., Results: The results of our study demonstrate that structural and contextual barriers limited PPR activities at political, social, and economic levels in each country, as well as through the structure of the health care system. Respondents believe that top-level government officials had insufficient political will for prioritizing pandemic PPR and post-COVID-19 recovery programs within their countries' health agendas., Discussion: We recommend a regional COVID-19 task force, post-pandemic recovery, social and economic protection for vulnerable groups, improved primary health care and surveillance systems, risk communication strategies, and community engagement to place pandemic PPR on Argentina, Brazil, Colombia, and Peru and other South American countries' national public health agendas., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ramírez Varela, Touchton, Miranda, Mejía Grueso, Laajaj, Carrasquilla, Vives Florez, Vesga Gaviria, Ortiz Hoyos, Vanegas Duarte, Velásquez Morales, Velasco and Restrepo Restrepo.)

The adult neurogenic niche in the hippocampus is maintained through activation of reversibly quiescent neural stem cells (NSCs) with radial glia-like morphology (RGLs). Here, we show that the expression of SoxD transcription factors Sox5 and Sox6 is enriched in activated RGLs. Using inducible deletion of Sox5 or Sox6 in the adult mouse brain, we show that both genes are required for RGL activation and the generation of new neurons. Conversely, Sox5 overexpression in cultured NSCs interferes with entry in quiescence. Mechanistically, expression of the proneural protein Ascl1 (a key RGL regulator) is severely downregulated in SoxD-deficient RGLs, and Ascl1 transcription relies on conserved Sox motifs. Additionally, loss of Sox5 hinders the RGL activation driven by neurogenic stimuli such as environmental enrichment. Altogether, our data suggest that SoxD genes are key mediators in the transition of adult RGLs from quiescence to an activated mitotic state under physiological situations., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Hippocampal sclerosis, the major neuropathological hallmark of temporal lobe epilepsy, is characterized by different patterns of neuronal loss. The mechanisms of cell-type-specific vulnerability and their progression and histopathological classification remain controversial. Using single-cell electrophysiology in vivo and immediate-early gene expression, we reveal that superficial CA1 pyramidal neurons are overactive in epileptic rodents. Bulk tissue and single-nucleus expression profiling disclose sublayer-specific transcriptomic signatures and robust microglial pro-inflammatory responses. Transcripts regulating neuronal processes such as voltage channels, synaptic signaling, and cell adhesion are deregulated differently by epilepsy across sublayers, whereas neurodegenerative signatures primarily involve superficial cells. Pseudotime analysis of gene expression in single nuclei and in situ validation reveal separated trajectories from health to epilepsy across cell types and identify a subset of superficial cells undergoing a later stage in neurodegeneration. Our findings indicate that sublayer- and cell-type-specific changes associated with selective CA1 neuronal damage contribute to progression of hippocampal sclerosis., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Leucine rich repeat kinase 2 (LRRK2) is an enigmatic enzyme and a relevant target for Parkinson's disease (PD). However, despite the significant amount of research done in the past decade, the precise function of LRRK2 remains largely unknown. Moreover, the therapeutic potential of its inhibitors is in its infancy with the first clinical trial having just started. In the present work, the molecular mechanism of LRRK2 in the control of neurogenesis or gliogenesis was investigated. We designed and synthesized novel benzothiazole-based LRRK2 inhibitors and showed that they can modulate the Wnt/β-catenin signaling pathway. Furthermore, compounds 5 and 14 were able to promote neural progenitors proliferation and drive their differentiation toward neuronal and oligodendrocytic cell fates. These results suggest potential new avenues for the application of LRRK2 inhibitors in demyelinating diseases in which oligodendrocyte cell-death is one of the pathological features.

The generation of new neurons is a lifelong process in many vertebrate species that provides an extra level of plasticity to several brain circuits. Frequently, neurogenesis in the adult brain is considered a continuation of earlier developmental processes as it relies in the persistence of neural stem cells, similar to radial glia, known as radial glia-like cells (RGLs). However, adult RGLs are not just leftovers of progenitors that remain in hidden niches in the brain after development has finished. Rather, they seem to be specified and set aside at specific times and places during embryonic and postnatal development. The adult RGLs present several cellular and molecular properties that differ from those observed in developmental radial glial cells such as an extended cell cycle length, acquisition of a quiescence state, a more restricted multipotency and distinct transcriptomic programs underlying those cellular processes. In this minireview, we will discuss the recent attempts to determine how, when and where are the adult RGLs specified.

The proximodistal axis is considered a major organizational principle of the hippocampus. At the interface between the hippocampus and other brain structures, CA2 apparently breaks this rule. The region is involved in social, temporal, and contextual memory function, but mechanisms remain elusive. Here, we reveal cell-type heterogeneity and a characteristic expression gradient of the transcription factor Sox5 within CA2 in the rat. Using intracellular and extracellular recordings followed by neurochemical identification of single cells, we find marked proximodistal trends of synaptic activity, subthreshold membrane potentials, and phase-locked firing coupled to theta and gamma oscillations. Phase-shifting membrane potentials and opposite proximodistal correlations with theta sinks and sources at different layers support influences from different current generators. CA2 oscillatory activity and place coding of rats running in a linear maze reflect proximodistal state-dependent trends. We suggest that the structure and function of CA2 are distributed along the proximodistal hippocampal axis., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)

Overcoming the lack of effective treatments and the continuous clinical trial failures in neurodegenerative drug discovery might require a shift from the prevailing paradigm targeting pathogenesis to the one targeting simultaneously neuroprotection and neuroregeneration. In the studies reported herein, we sought to identify small molecules that might exert neuroprotective and neuroregenerative potential as tools against neurodegenerative diseases. In doing so, we started from the reported neuroprotective/neuroregenerative mechanisms of psychotropic drugs featuring a tricyclic alkylamine scaffold. Thus, we designed a focused-chemical library of 36 entries aimed at exploring the structural requirements for efficient neuroprotective/neuroregenerative cellular activity, without the manifestation of toxicity. To this aim, we developed a synthetic protocol, which overcame the limited applicability of previously reported procedures. Next, we evaluated the synthesized compounds through a phenotypic screening pipeline, based on primary neuronal systems. Phenothiazine 2Bc showed improved neuroregenerative and neuroprotective properties with respect to reference drug desipramine (2Aa). Importantly, we have also shown that 2Bc outperformed currently available drugs in cell models of Alzheimer's and Parkinson's diseases and attenuates microglial activation by reducing iNOS expression.

GLI1, GLI2 and GLI3 form a family of transcription factors which regulate development by mediating the action of Hedgehog (Hh) morphogens. Accordingly, inactivating variants in GLI2 and GLI3 are found in several developmental disorders. In contrast, loss-of-function mutations in GLI1 have remained elusive, maintaining enigmatic the role of this gene in the human embryo. We describe eight patients from three independent families having biallelic truncating variants in GLI1 and developmental defects overlapping with Ellis-van Creveld syndrome (EvC), a disease caused by diminished Hh signaling. Two families had mutations in the last exon of the gene and a third family was identified with an N-terminal stop gain variant predicted to be degraded by the NMD-pathway. Analysis of fibroblasts from one of the patients with homozygous C-terminal truncation of GLI1 demonstrated that the corresponding mutant GLI1 protein is fabricated by patient cells and becomes upregulated in response to Hh signaling. However, the transcriptional activity of the truncated GLI1 factor was found to be severely impaired by cell culture and in vivo assays, indicating that the balance between GLI repressors and activators is altered in affected subjects. Consistent with this, reduced expression of the GLI target PTCH1 was observed in patient fibroblasts after chemical induction of the Hh pathway. We conclude that GLI1 inactivation is associated with a phenotypic spectrum extending from isolated postaxial polydactyly to an EvC-like condition., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Leucine-rich repeat kinase 2 (LRRK2) is one of the most pursued targets for Parkinson's disease (PD) therapy. Moreover, it has recently described its role in regulating Wnt signaling and thus, it may be involved in adult neurogenesis. This new hypothesis could give rise to double disease-modifying agents firstly by the benefits of inhibiting LRRK2 and secondly by promoting adult neurogenesis. Herein we report, the design, synthesis, biological evaluation, SAR and potential binding mode of indoline-like LRRK2 inhibitors and their preliminary neurogenic effect in neural precursor cells isolated from adult mice ventricular-subventricular zone. These results open new therapeutic horizons for the use of LRRK2 inhibitors as neuroregenerative agents. Moreover, the indolinone derivatives here prepared, inhibitors of the kinase activity of LRRK2, may be considered as pharmacological probes to study the potential neuroregeneration of the damaged brain., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

During vertebrate embryonic development, the spinal cord is formed by the neural derivatives of a neuromesodermal population that is specified at early stages of development and which develops in concert with the caudal regression of the primitive streak. Several processes related to spinal cord specification and maturation are coupled to this caudal extension including neurogenesis, ventral patterning and neural crest specification and all of them seem to be crucially regulated by Fibroblast Growth Factor (FGF) signaling, which is prominently active in the neuromesodermal region and transiently in its derivatives. Here we review the role of FGF signaling in those processes, trying to separate its different functions and highlighting the interactions with other signaling pathways. Finally, these early functions of FGF signaling in spinal cord development may underlay partly its ability to promote regeneration in the lesioned spinal cord as well as its action promoting specific fates in neural stem cell cultures that may be used for therapeutical purposes.

A prevalent developmental mechanism for the assignment of cell identities is the production of spatiotemporal concentration gradients of extracellular signaling molecules that are interpreted by the responding cells. One of such signaling systems is the Shh gradient that controls neuronal subtype identity in the ventral spinal cord. Using loss and gain of function approaches in chick and mouse embryos, we show here that the fibroblast growth factor (FGF) signaling pathway is required to restrict the domains of ventral gene expression as neuroepithelial cells become exposed to Shh during caudal extension of the embryo. FGF signaling activates the expression of the Shh receptor and negative pathway regulator Patched 2 (Ptch2) and therefore can enhance a negative feedback loop that restrains the activity of the pathway. Thus, we identify one of the mechanisms by which FGF signaling acts as a modulator of the onset of Shh signaling activity in the context of coordination of ventral patterning and caudal axis extension. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 956-971, 2016., (© 2015 Wiley Periodicals, Inc.)

The specific actions of insulin-like growth factor-I (IGF-I) and the role of brain-derived IGF-I during hippocampal neurogenesis have not been fully defined. To address the influence of IGF-I on the stages of hippocampal neurogenesis, we studied a postnatal/adult global Igf-I knockout (KO) mice (Igf-I(-/-) ) and a nervous system Igf-I conditional KO (Igf-I(Δ/Δ) ). In both KO mice we found an accumulation of Tbr2(+) -intermediate neuronal progenitors, some of which were displaced in the outer granule cell layer (GCL) and the molecular layer (ML) of the dentate gyrus (DG). Similarly, more ectopic Ki67(+) - cycling cells were detected. Thus, the GCL was disorganized with significant numbers of Prox1(+) -granule neurons outside this layer and altered morphology of radial glial cells (RGCs). Dividing progenitors were also generated in greater numbers in clonal hippocampal stem cell (HPSC) cultures from the KO mice. Indeed, higher levels of Hes5 and Ngn2, transcription factors that maintain the stem and progenitor cell state, were expressed in both HPSCs and the GCL-ML from the Igf-I(Δ/Δ) mice. To determine the impact of Igf-I deletion on neuronal generation in vivo, progenitors in Igf-I(-/-) and Igf-I(+/+) mice were labeled with a GFP-expressing vector. This revealed that in the Igf-I(-/-) mice more GFP(+) -immature neurons were formed and they had less complex dendritic trees. These findings indicate that local IGF-I plays critical roles during postnatal/adult hippocampal neurogenesis, regulating the transition from HPSCs and progenitors to mature granule neurons in a cell stage-dependent manner. Stem Cells 2016;34:2194-2209., (© 2016 AlphaMed Press.)

The basic organization of somatosensory circuits in the spinal cord is already setup during the initial patterning of the dorsal neural tube. Extrinsic signals, such as Wnt and TGF-β pathways, activate combinatorial codes of transcription factors that are responsible for generating a pattern of discrete domains of dorsal progenitors (dp). These progenitors will give rise to distinct dorsal interneurons (dI). The Wnt/ βcatenin signaling pathway controls specification of dp/dI1-3 progenitors and interneurons. According to the current model in the field, Wnt/βcatenin activity seems to act in a graded fashion in the spinal cord, as different relative levels determine the identity of adjacent progenitors. However, it is not clear how this activity gradient is controlled and how the identities of dI1-3 are differentially regulated by Wnt signalling. We have determined that two SoxD transcription factors, Sox5 and Sox6, are expressed in restricted domains of dorsal progenitors in the neural tube. Using gain- and loss-of function approaches in chicken embryos, we have established that Sox5 controls cell fate specification of dp2 and dp3 progenitors and, as a result, controls the correct number of the corresponding dorsal interneurons (dI2 and dI3). Furthermore, Sox5 exerts its function by restricting dorsally Wnt signaling activity via direct transcriptional induction of the negative Wnt pathway regulator Axin2. By that way, Sox5 acts as a Wnt pathway modulator that contributes to sharpen the dorsal gradient of Wnt/βcatenin activity to control the distinction of two functionally distinct types of interneurons, dI2 and dI3 involved in the somatosensory relay., (© 2014 Wiley Periodicals, Inc.)

Primary cutaneous B-cell lymphomas (PCBCL) are rare. Marginal zone lymphomas and follicle center lymphomas (FCL) represent a majority of these cases, and a significant number of cases present with multiple lesions. It is unclear whether multiple lesions in PCBCL represent dissemination of a single clone or multiple new primary lymphomas. In the current study, we analyzed paired samples from 20 PCBCL patients at more than 1 site (16) or at the same site at different time points (4) and 12 patients with benign lymphoid infiltrates to investigate for the presence or absence of a clone, and if present, whether the clones were identical. Both IGH@ and IGK@ rearrangements were tested using the BIOMED-2 protocol. We identified a clone (IGH@ and/or IGK@) in 19 of 20 (95%) PCBCL patients and 2 of 12 (17%) benign lymphoid infiltrate patients. The B-cell clones were proven to be identical in 11 of 20 (55%) PCBCL patients, including 7 of 16(44%) biopsies from patients with 2 different sites and 4 of 4 biopsies (100%) from patients at the same site but different time points. In 4 cases (3 FCL and 1 marginal zone lymphoma), different clones were detected at different sites, suggesting the possibility of a second simultaneous primary lymphoma. Our results indicate that the presence of identical clones is highly suggestive of lymphoma. To our knowledge, this is the first report to investigate the detection of identical clones in 2 distinct biopsies in PCBCL patients. Although the study is small and the results need to be confirmed in a larger study, these findings suggest that a subset of PCBCL at different sites may represent different primary tumors rather than occurrence of a single disease.

We examined the relationship between the 677C >T polymorphism in the MTHFR gene and tHcy in normotensive (NT) and hypertensive (HT) subjects and the influence of sex and age in a cross-sectional study. Smoking habits, history of vascular disease, diabetes, and tHcy were significantly associated with T allele as hypertension risk factors. The T allele was significantly related with higher tHcy in (i) men versus women (P < .01), (ii) men and women older than 47 years versus the younger ones (P < .05 and P < .001, respectively), (iii) HT women versus NT women (P < .01), and (iv) older HT women versus older NT women (P < .01). We found an association between the 677C>T MTHFR polymorphism and tHcy with hypertension that in women is manifested with age.

Betaine-homocysteine S-methyltransferase (BHMT) is an enzyme that converts homocysteine (Hcy) to methionine using betaine as a methyl donor. Betaine also acts as osmolyte in kidney medulla, protecting cells from high extracellular osmolarity. Hepatic BHMT expression is regulated by salt intake. Hormones, particularly corticosteroids, also regulate BHMT expression in rat liver. We investigated to know whether the corticoadrenal activity plays a role in kidney BHMT expression. BHMT activity in rat kidneys is several orders of magnitude lower than in rat livers and only restricted to the renal cortex. This study confirms that corticosteroids stimulate BHMT activity in the liver and, for the first time in an animal model, also up-regulate the BHMT gene expression. Besides, unlike the liver, corticosteroids in rat kidney down-regulate BHMT expression and activity. Given that the classical effect of adrenocortical activity on the kidney is associated with sodium and water re-absorption by the distal tubule leading to volume expansion, by promoting lesser use of betaine as a methyl donor, corticosteroids would preserve betaine for its other role as osmoprotectant against changes in the extracellular osmotic conditions. We conclude that corticosteroids are, at least in part, responsible for the inhibition of BHMT expression and activity in rat kidneys.

Coordination between functionally related adjacent tissues is essential during development. For example, formation of trunk neural crest cells (NCCs) is highly influenced by the adjacent mesoderm, but the molecular mechanism involved is not well understood. As part of this mechanism, fibroblast growth factor (FGF) and retinoic acid (RA) mesodermal gradients control the onset of neurogenesis in the extending neural tube. In this paper, using gain- and loss-of-function experiments, we show that caudal FGF signaling prevents premature specification of NCCs and, consequently, premature epithelial-mesenchymal transition (EMT) to allow cell emigration. In contrast, rostrally generated RA promotes EMT of NCCs at somitic levels. Furthermore, we show that FGF and RA signaling control EMT in part through the modulation of elements of the bone morphogenetic protein and Wnt signaling pathways. These data establish a clear role for opposition of FGF and RA signaling in control of the timing of NCC EMT and emigration and, consequently, coordination of the development of the central and peripheral nervous system during vertebrate trunk elongation.

Homocysteine, a non-protein amino acid, important risk factor for atherosclerosis and thrombosis, causes dysfunction of vascular endothelial cells traduced in inadequate vasodilatation mechanism, is pro-inflammatory and induces endoplasmic reticulum stress. The more reactive conformation is the homocysteine thiolactone (HcyT), product to the nonspecific action of methionyl-tRNA synthetase, which is incorporated into proteins by disulfide bonds (S-homocysteinilation) or amide bonds (N-homocysteinilation) affecting protein structure and function leading to cell toxicity, autoimmune responses and atherogenesis. The enzyme paraoxonase-1 (PON1), part of high density lipoprotein (HDL), had been studied only for its ability to hydrolyze organophosphate derivatives. But, more recently it has been attributed other important role. The enzyme activities are involving in protecting against the development of atherosclerosis, by preventing oxidation of lipoproteins and hydrolyze HcyT. There is growing evidence about the protective role of PON1 in vascular disease. Genetic factors (polymorphisms of the PON1), environmental and lifestyle influence their concentration and biological activity, but drugs used as cardioprotectives and lipid-lowering or others, such as antibiotics and steroids, are also important modulators. This review is an updated of the most prominent information on clinical and experimental studies for understanding the role of the PON-1 in the protection against development of atherosclerosis.

Genes of the SOX family of high-mobility group transcription factors are essential during nervous system development. In this study, we show that SOX5 is expressed by neural progenitors in the chick spinal cord and is turned off as differentiation proceeds. The overexpression of SOX5 in neural progenitors causes premature cell cycle exit and prevents terminal differentiation. Conversely, knocking down SOX5 protein extends the proliferative period of neural progenitors and causes marked cell death in a dorsal interneuron (dI3) population. Furthermore, SOX5 reduces WNT-beta-catenin signalling, thereby triggering the expression of the negative regulator of the pathway axin2. We propose that SOX5 regulates the timing of cell cycle exit by opposing WNT-beta-catenin activity on cell cycle progression.

Background: Optimal treatment of indolent primary cutaneous B-cell lymphoma (CBCL), marginal zone lymphoma, and follicle center lymphoma, presenting as multiple lesions, has yet to be established. Rituximab is a chimeric monoclonal IgG1 antibody directed against the CD20 antigen of B cells. Clinical efficacy of systemic rituximab in CBCL has yet to be established., Objective: We sought to assess the efficacy of systemic rituximab in the treatment of CBCL., Methods: This was a retrospective study of 15 patients with indolent CBCL treated with intravenous rituximab (375 mg/m(2)) as a single agent. Variable maintenance regimen was used in a subset of patients. Responses were categorized as complete response, partial response, stable disease, or progressive disease. The efficacy end points included were objective response rate, time to response, time to progression, and duration of response., Results: Ten patients with follicle center lymphoma and 5 with marginal zone lymphoma were included. The objective response rate was 87% (60% complete response, 27% partial response). All patients with follicle center lymphoma had a response with 80% achieving complete response. Of the patients with marginal zone lymphoma, 3 had a response, one stable disease, and one progressive disease. Median follow-up was 36 months. Median time to response, duration of response, and time to progression was 30 days, 24 months, and 24 months, respectively., Limitations: The study was limited by the small sample size and retrospective design., Conclusions: This study, although small, suggests that rituximab is a reasonable first-line treatment option for indolent CBCL with multiple lesions where local treatment is not effective or desirable.

Primary cutaneous B-cell lymphomas (CBCL) are a diverse group of lymphomas that are limited to the skin at the time of diagnosis. Recently, standardized polymerase chain reaction protocols for immunoglobulin (Ig) rearrangement in nodal malignancies using the BIOMED-2 method have been studied extensively. However, reports of investigations of Ig clonality in CBCL using the BIOMED-2 method have been scant. We hypothesized that clonality detection in CBCL with the BIOMED-2 method could effectively distinguish malignant from benign B-cell-rich infiltrates in the skin. Formalin-fixed tissue samples from 26 patients with CBCL and 23 with benign lymphoid infiltrates were analyzed for Ig clonality using standardized BIOMED-2 polymerase chain reaction protocols. The (14;18) translocation was also assessed. A clone was detected in 22 (85%) of the 26 patients with CBCL [12/15 (80%) marginal zone B-cell lymphoma; 10/11 (91%) follicle center lymphoma] and in 1 (4%) of the 23 patients with benign infiltrates. The (14;18) translocation was present in 3 (12%) of the 26 patients with CBCL [1/15 (7%) marginal zone B-cell lymphoma; 2/11 (18%) follicle center lymphoma]. Our preliminary data indicate that Ig clonality can be detected in formalin-fixed samples of CBCL with meaningful sensitivity (85%) and high specificity (96%) using the BIOMED-2 method. This study forms the basis for further investigating the role of Ig clonality in distinguishing CBCL from benign lymphoid infiltrates that may pose a challenge in morphologic diagnosis.

Sox5 is a member of the SoxD group of HMG-box transcription factors that, during the early stages of development, promotes neural crest generation. However, little is known about Sox5 function in neural crest derivatives such as the peripheral sensory nervous system. We have analysed the embryonic expression of Sox5 during chick cranial ganglia development, from the stages of ganglia condensation to those of differentiation. During this period, Sox5 expression is maintained in the crest-derived satellite glial cells in all the cranial ganglia. In contrast, Sox5 is only transiently expressed in a subpopulation of differentiating neurons of both neural crest and placode origin. This detailed analysis provides a good base to dissect the possible role of Sox5 in neural cell fate determination by future functional approaches., ((c) 2007 Wiley-Liss, Inc.)

Retinoic acid (RA) signalling ensures that vertebrate mesoderm segmentation is bilaterally synchronized, and corrects transient interferences from asymmetric left-right (L-R) signals involved in organ lateralization. Snail genes participate in both these processes and, although they are expressed symmetrically in the presomitic mesoderm (PSM), Snail1 transcripts are asymmetrically distributed in the L-R lateral mesoderm. We show that the alteration of the symmetric Snail expression in the PSM induces asynchronous somite formation. Furthermore, in the absence of RA signalling, normal asymmetric Snail1 expression in the lateral mesoderm is extended to the PSM, desynchronizing somitogenesis. Thus, Snail1 is the first cue corrected by RA in the PSM to ensure synchronized bilateral segmentation.

The development of the neural crest up to the stage where they leave the neural tube can be observed as a series of concatenated but independent events that involve dorsalization of the neural plate/neural tube, neural crest induction, segregation and stabilization, epithelial to mesenchymal transition and delamination. During all these processes, the nascent neural crest cells are subjected to the influence of different signals and have to overcome competition for cell fate and apoptotic signals. In addition, striking rostrocaudal differences unveil how the regulatory cascades are somehow different but still can lead to the production of bona fide neural crest cells.

The Snail zinc-finger transcription factors trigger epithelial-mesenchymal transitions (EMTs), endowing epithelial cells with migratory and invasive properties during both embryonic development and tumor progression. During EMT, Snail provokes the loss of epithelial markers, as well as changes in cell shape and the expression of mesenchymal markers. Here, we show that in addition to inducing dramatic phenotypic alterations, Snail attenuates the cell cycle and confers resistance to cell death induced by the withdrawal of survival factors and by pro-apoptotic signals. Hence, Snail favors changes in cell shape versus cell division, indicating that with respect to oncogenesis, although a deregulation/increase in proliferation is crucial for tumor formation and growth, this may not be so for tumor malignization. Finally, the resistance to cell death conferred by Snail provides a selective advantage to embryonic cells to migrate and colonize distant territories, and to malignant cells to separate from the primary tumor, invade, and form metastasis.

A molecular oscillator regulates the pace of vertebrate segmentation. Here, we show that the oscillator (clock) controls cyclic initiation of transcription in the unsegmented presomitic mesoderm (PSM). We identify an evolutionarily conserved 2.3 kb region in the murine Lunatic fringe (Lfng) promoter that drives periodic expression in the PSM. This region includes conserved blocks required for enhancing and repressing cyclic Lfng transcription, and to prevent continued expression in formed somites. We also show that dynamic expression in the cycling PSM is lost in the total absence of Notch signaling, and that Notch signaling acts directly via CBF1/RBP-Jkappa binding sites to regulate Lfng. These results are consistent with a model in which oscillatory Notch signaling underlies the segmentation clock and directly activates and indirectly represses Lfng expression.

While the role of heat shock proteins under experimental stress conditions is clearly characterized, their expression in unstressed cells and tissues and their functions in normal cell physiology, besides their chaperone action, remain largely undetermined. We report here the identification in chicken of the antigen recognized by the monoclonal antibody PM1 [Hernández-Sánchez et al. (1994) Eur. J. Neurosci., 6,1801-1810] as the noninducible chaperone heat-shock cognate 70 (Hsc70). Its identity was determined by partial peptide sequencing, immuno-crossreactivity and two-dimensional gel-electrophoresis. In addition, we examined its expression during chick embryo retinal neurogenesis. The early widespread Hsc70 immunostaining corresponding to most, if not all, of the neuroepithelial cells becomes restricted to a subpopulation of these cells in the peripheral retina as development proceeds. On the other hand, retinal ganglion cells, differentiating in the opposite central-to-peripheral gradient, retained Hsc70 immunostaining. Other molecular chaperones, the heat-shock proteins Hsp40, Hsp60 and Hsp90, did not seem to compensate the loss of Hsc70. They also showed decreasing immunostaining patterns as neurogenesis proceeds, although distinctive from that of Hsc70, whereas Hsp70 was not detected in the embryonic retina. This precise cellular and developmental regulation of Hsc70, a generally considered constitutive molecular chaperone, in unstressed embryos, together with the expression of other chaperones, provides new tools and a further insight on neural precursor heterogeneity, and suggests possible specific cellular roles of chaperone function during vertebrate neurogenesis.

Evidence that the insulin-like growth factors play a role in embryonic as well as postnatal growth and central nervous system development has accumulated recently from studies using knock-out mice models. However, no effects of IGF-I and II have been demonstrated prior to organogenesis in these studies. We summarize here results supporting the role of insulin (or its precursor proinsulin) in vertebrate development prior to the expression of IGFs. (Pro)insulin mRNA is expressed in the chick embryo during neurulation and early organogenesis and its inhibition by antisense oligodeoxynucleotides increase apoptosis. In another system, proliferative neuroretina, (pro)insulin expression predominates over IGF-I expression. Modulation of apoptosis by (pro)insulin in retina may be largely responsible for the observed stimulation of DNA synthesis and neuronal differentiation. These effects are elicited as well by IGF-I, expressed later in neuroretina. Thus, these polypeptides have complementary expression in early embryos which suggests coordinated actions during development.

Insights have emerged concerning insulin function during development, from the finding that apoptosis during chicken embryo neurulation is prevented by prepancreatic (pro)insulin. While characterizing the molecules involved in this survival effect of insulin, we found insulin-dependent regulation of the molecular chaperone heat shock cognate 70 kDa (Hsc70), whose cloning in chicken is reported here. This chaperone, generally considered constitutively expressed, showed regulation of its mRNA and protein levels in unstressed embryos during early development. More important, Hsc70 levels were found to depend on endogenous (pro)insulin, as shown by using antisense oligodeoxynucleotides against (pro)insulin mRNA in cultured neurulating embryos. Further, in the cultured embryos, apoptosis affected mainly cells with the lowest level of Hsc70, as shown by simultaneous Hsc70 immunostaining and terminal deoxynucleotidyltransferase-mediated UTP nick end labeling. These results argue in favor of Hsc70 involvement, modulated by embryonic (pro)insulin, in the prevention of apoptosis during early development and suggest a role for a molecular chaperone in normal embryogenesis.

Purpose: To investigate current antibiotic prophylactic usage for arteriography, angioplasty, vascular stent placement, transjugular intrahepatic portosystemic shunt placement (TIPS), tunneled-port placement, inferior vena cava (IVC) filter placement, biliary drainage, genitourinary drainage, abdominal drainage, and enteral tube placement with an aim to better clarify indications and regimens for prophylaxis., Methods: A questionnaire regarding antibiotic prophylactic usage was sent to 2,039 members of the Society of Cardiovascular and Interventional Radiology (SCVIR). There were 401 respondents. Replies were evaluated for frequency and indications of prophylaxis, specific prophylaxis used, and clarity of indications for prophylaxis., Results: A majority of responders never used prophylaxis for arteriography, angioplasty, vascular stent placement, IVC filter placement, abdominal drainage, and enteral tube placement. Infective complication rates from nonusage ranged between 1% and 15%. Approximately 45% always used prophylaxis for tunneled-port placement and TIPS with a 13%-16% infective complication rate among nonusers. In contrast, a majority of responders always used prophylaxis for biliary and genitourinary drainage, with a 40%-58% infective complication rate in nonusers. More than 70% of responders believed that the indications for prophylaxis were not clear for arteriography, angioplasty, vascular stent placement, tunneled-port placement, TIPS, IVC filter placement, and enteral tube placement, and in contrast, that the indications for prophylaxis for biliary and genitourinary drainage were clear. Fifty-one percent of responders believed that indications for prophylaxis for abdominal drainage were clear., Conclusions: Indications for antibiotic prophylaxis are not clear to interventionalists for a large number of vascular and nonvascular interventional procedures. Prophylaxis appears unnecessary for routine arteriography, angioplasty, IVC filter placement, vascular stent placement, or enterostomy tube placement. Antibiotic prophylaxis is warranted for TIPS and tunneled-port placement. Conversely, indications for antibiotic prophylaxis are clear to interventionalists for biliary and genitourinary drainage procedures. Routine prophylaxis remains warranted for both.

The characterization of (pro)insulin as an early embryonic growth factor requires demonstration of its expression and cellular effects in vivo. By in situ hybridization, we found widespread preproinsulin transcripts in the chick embryo throughout gastrulation and neurulation, before the beginning of preproinsulin-like growth factor I expression and pancreatic organogenesis. To analyze the prepancreatic (pro)insulin effect on apoptotic cell death, we treated embryos with antisense oligodeoxynucleotides in ovo and in vitro. The specific effect of two preproinsulin messenger RNA (mRNA) antisense oligodeoxynucleotides was confirmed by the decrease in a biosynthetically labeled protein immunoprecipitated with antiinsulin Igs. Insulin receptor mRNA antisense oligodeoxynucleotide applied in ovo increased by 2.7-fold the level of apoptosis in the 1.5-day embryo (neurulation) compared with that in its random sequence control. In a whole embryo culture, apoptosis increased by 25-35% with the addition of preproinsulin or insulin receptor mRNAs antisense oligodeoxynucleotides, respectively, whereas it decreased by 64% after 10 h in the presence of 10(-8) M chicken insulin. Exogenous insulin also rescued the death induced by preproinsulin antisense oligonucleotides. These findings provide evidence for an autocrine/paracrine role ofpreproinsulin gene products acting through the insulin receptor in the control of cell survival/death during early embryonic development.

cCdx-B (formerly cHox-cad 2) is a chick homeobox-containing gene related to the Drosophila caudal. Compared with other caudal homologues, its similarity is highest with the murine Cdx-4. In the present study, we characterize the localization of cCdx-B transcripts to the caudal region of the embryo by using reverse transcription-polymerase chain reaction (RT-PCR) and, in detail, by using in situ hybridization. Chick embryos from gastrulation to early organogenesis were hybridized with digoxigenin-labeled riboprobes, and the pattern of expression of cCdx-B mRNA was analyzed in wholemount embryos and in tissue sections. In the early gastrula, transcripts were localized in a gradient through the caudal half of the embryo, in the epiblast and the mesoderm cells, but not including Hensen's node. During neurulation, cCdx-B transcripts were found more rostrally, with high levels localized in Hensen's node and the posterior neural plate. Expression was also high in paraxial mesoderm, with a rostral limit in the most recently formed somite. There was no expression in definitive endoderm. During late neurulation and tail bud formation, cCdx-B mRNA expression regressed posteriorly and was finally confined to the tail bud region. This pattern of expression of cCdx-B, regulated in time and space, is different from that of the other known chick caudal homologue, cCdx-A. Both genes may play a coordinated role in the posterior axial patterning of the chick embryo, whereas cCdx-B may specify further the identity of the tail region.

Despite the absence of a pancreas, which develops between embryonic day 3 (E3) to E4, previous studies showed that insulin receptors are widely expressed in chicken embryos from the blastoderm stage (unincubated embryo, E0) through gastrulation (E0.5-E1), neurulation (E1.5-E2), and organogenesis. We now characterize prepancreatic preproinsulin gene expression and its regulation, using a highly sensitive modification of the polymerase chain reaction. We found preproinsulin messenger RNA (mRNA) expression at all stages, from the unincubated chicken blastoderm through early organogenesis, with the highest expression in embryos undergoing gastrulation. In situ hybridization analysis of E1-E1.5 embryos in toto showed widespread distribution of preproinsulin mRNA in a pattern similar to that of insulin receptor mRNA. In contrast, insulin-like growth factor-I mRNA expression appeared later than preproinsulin mRNA in the embryo; it was first demonstrable in the head portion of E3 and was found in head, trunk, and caudal regions by E4. With a novel culture system for chicken embryos during neurulation, we examined whether glucose regulated prepancreatic preproinsulin mRNA expression. Embryos cultured in glucose-free medium had increased preproinsulin mRNA with respect to the value in ovo, but the addition of 17 mM glucose had no stimulatory effect. In marked contrast, in organ cultures of E13 pancreas, insulin mRNA expression decreased in glucose-free medium by 50% relative to that in ovo. The addition of glucose restored the levels to a concentration similar to that found in ovo. Exogenous insulin added to cultured E1.5 embryos increased protein and DNA synthesis. We conclude that the preproinsulin gene is widely expressed in chicken embryo structures throughout gastrulation and neurulation. This prepancreatic preproinsulin mRNA is differentially regulated compared to the pancreatic mRNA. Preproinsulin gene products may have a role in cell proliferation, differentiation, or survival in very early avian embryos at a time when insulin-like growth factor-I expression is absent or undetectable.

In May 1976 an investigation of a factory in Puerto Rico which formulates oral contraceptives revealed that during the previous 12 months five of the company's twenty-five employees (20%), and twelve of the company's thirty female employees (40%) had experienced symptoms associated with hyperestrogenism. The affected males had gynecomastia and three of them also reported a history of decreased libido or impotence. The affected females each had had at least one episode of intermenstrual bleeding during the preceding 12 months. There was an estimated relative risk of 4.3 for intermenstrual bleeding in nonclerical female employees compared with matched controls who did not work at the plant. Elevated levels of plasma ethinyl estradiol were twice as frequent in the two highest-risk job categories compared with the rest of the factory population, but the difference in prevalence of elevated levels was not statistically significant (P = 0.08). Wide variations in mestranol concentration were noted in the environmental dust samples. Prompt consideration should be given to establishing health standards for persons occupationally exposed to estrogens in view of the possible long-term sequelae of such exposure.