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The escalating prevalence of Parkinson's disease (PD) underscores the need for innovative therapeutic interventions since current palliative measures, including the standard l-Dopa formulations, face challenges of tolerance and side effects while failing to address the underlying neurodegenerative processes. Here, we introduce DAD9 , a novel conjugate molecule that aims to combine symptomatic relief with disease-modifying strategies for PD. Crafted through knowledge-guided chemistry, the molecule combines a nonantibiotic doxycycline derivative with dopamine, preserving neuroprotective attributes while maintaining dopaminergic agonism. This compound exhibited no off-target effects on PD-relevant cell functions and sustained antioxidant and anti-inflammatory properties of the tetracycline precursor. Furthermore, it effectively interfered with the formation and seeding of toxic α-synuclein aggregates without producing detrimental oxidative species. In addition, DAD9 was able to activate dopamine receptors, and docking simulations shed light onto the molecular details of this interaction. These findings position DAD9 as a potential neuroprotective dopaminergic agonist, promising advancements in PD therapeutics.

The antibiotic tetracycline demeclocycline (DMC) was recently reported to rescue α-synuclein (α-Syn) fibril-induced pathology. However, the antimicrobial activity of DMC precludes its potential use in long-term neuroprotective treatments. Here, we synthesized a doubly reduced DMC (DDMC) derivative with residual antibiotic activity and improved neuroprotective effects. The molecule was obtained by removal the dimethylamino substituent at position 4 and the reduction of the hydroxyl group at position 12a on ring A of DMC. The modifications strongly diminished its antibiotic activity against Gram-positive and Gram-negative bacteria. Moreover, this compound preserved the low toxicity of DMC in dopaminergic cell lines while improving its ability to interfere with α-Syn amyloid-like aggregation, showing the highest effectiveness of all tetracyclines tested. Likewise, DDMC demonstrated the ability to reduce seeding induced by the exogenous addition of α-Syn preformed fibrils (α-Syn PFF ) in biophysical assays and in a SH-SY5Y-α-Syn-tRFP cell model. In addition, DDMC rendered α-Syn PFF less inflammogenic. Our results suggest that DDMC may be a promising drug candidate for hit-to-lead development and preclinical studies in Parkinson's disease and other synucleinopathies.

MAGI-1 is a critical cellular scaffolding protein with over 110 different cellular and microbial protein interactors. Since the discovery of MAGI-1 in 1997, MAGI-1 has been implicated in diverse cellular functions such as polarity, cell-cell communication, neurological processes, kidney function, and a host of diseases including cancer and microbial infection. Additionally, MAGI-1 has undergone nomenclature changes in response to the discovery of an additional PDZ domain, leading to lack of continuity in the literature. We address the nomenclature of MAGI-1 as well as summarize many of the critical functions of the known interactions. Given the importance of many of the interactors, such as human papillomavirus E6, the Coxsackievirus and adenovirus receptor (CAR), and PTEN, the enhancement or disruption of MAGI-based interactions has the potential to affect cellular functions that can potentially be harnessed as a therapeutic strategy for a variety of diseases., (© 2022 The Authors. Biology of the Cell published by Wiley-VCH GmbH on behalf of Société Française des Microscopies and Société de Biologie Cellulaire de France.)

Background: Hospital readmission (HR) after surgery is considered a quality metric., Methods: Data on 2371 first-time adult kidney transplant (KT) recipients were collected to analyze the "early" (≤30 days) and "late" (31-365 days) HR patterns after KT at a single center over a 12-year time span (2002-2013)., Results: 30-day, 90-day, and 1-year HR were 31%, 41%, and 53%, respectively. Risk factors for HR included age >50, female sex, black race, BMI >30, transplant LOS >5 days, and pre-transplant time on dialysis >765 days. Indications for early (n = 749) and late (n = 508) HR were similar. Early HR (OR: 3.80, P = .007) and black race (OR: 2.38, P = .009) were associated with higher odds of 1-year graft failure while frequency (1-2, 3-4, 5+) of HR (ORs: 4.68, 8.36, 9.44, P < .001) and age > 50 (OR: 2.11, P = .007) were associated with higher odds of 1-year mortality. Transplant LOS > 5 days increased both odds of 1-year graft failure (OR: 3.51, P = .001) and mortality (OR: 2.05, P = .006). One-year graft and recipient survival were 96.7% and 94.8%, respectively., Conclusions: Hospital readmission was associated with reduced graft and patient survival; however, despite a relatively high and consistent HR rate after KT, overall 1-year graft and patient survival was high., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Macroalgal blooms are becoming an increasing problem in coastal regions worldwide and have been associated with a widespread decline of seagrass habitats. It is critical to measure macroalgal bloom (MB) impacts at broad spatial scales since seagrass seascape characteristics can influence feedback processes that regulate the resilience of seagrass ecosystems. We assessed the broad-scale spatial impacts of an MB formed by Anadyomene spp. on the seagrass seascapes in Biscayne Bay (Miami, US) using a multi-scale seascape approach. By integrating field and remote sensing data, our multi-scale approach showed significant reductions in seagrass foliage cover and a seascape structure transformation across the bloom extent. The landscape cover and patch extensiveness declined after the MB peak. Other spatial pattern metrics also showed that the seagrass seascape structure got fragmented. We demonstrated that a persistent MB could transform the structure of seagrass seascapes, hindering the resilience of seagrass habitats., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: We previously reported the novel activity of alloprimed CD8 T cells that suppress posttransplant alloantibody production. The purpose of the study is to investigate the expression and role of CXCR5 on antibody-suppressor CD8 T-cell function., Methods: C57BL/6 mice were transplanted with FVB/N hepatocytes. Alloprimed CD8 T cells were retrieved on day 7 from hepatocyte transplant recipients. Unsorted or flow-sorted (CXCR5CXCR3 and CXCR3CXCR5) alloprimed CD8 T-cell subsets were analyzed for in vitro cytotoxicity and capacity to inhibit in vivo alloantibody production following adoptive transfer into C57BL/6 or high alloantibody-producing CD8 knock out (KO) hepatocyte transplant recipients. Alloantibody titer was assessed in CD8 KO mice reconstituted with naive CD8 T cells retrieved from C57BL/6, CXCR5 KO, or CXCR3 KO mice. Antibody suppression by ovalbumin (OVA)-primed monoclonal OVA-specific t-cell receptor transgenic CD8+ T cells (OT-I) CXCR5 or CXCR3 CD8 T-cell subsets was also investigated., Results: Alloprimed CXCR5CXCR3CD8 T cells mediated in vitro cytotoxicity of alloprimed "self" B cells, while CXCR3CXCR5CD8 T cells did not. Only flow-sorted alloprimed CXCR5CXCR3CD8 T cells (not flow-sorted alloprimed CXCR3CXCR5CD8 T cells) suppressed alloantibody production and enhanced graft survival when transferred into transplant recipients. Unlike CD8 T cells from wild-type or CXCR3 KO mice, CD8 T cells from CXCR5 KO mice do not develop alloantibody-suppressor function. Similarly, only flow-sorted CXCR5CXCR3 (and not CXCR3CXCR5) OVA-primed OT-I CD8 T cells mediated in vivo suppression of anti-OVA antibody production., Conclusions: These data support the conclusion that expression of CXCR5 by antigen-primed CD8 T cells is critical for the function of antibody-suppressor CD8 T cells.

Humoral alloimmunity negatively impacts both short- and long-term cell and solid organ transplant survival. We previously reported that alloantibody-mediated rejection of transplanted hepatocytes is critically dependent on host macrophages. However, the effector mechanism(s) of macrophage-mediated injury to allogeneic liver parenchymal cells is not known. We hypothesized that macrophage-mediated destruction of allogeneic hepatocytes occurs by cell-cell interactions requiring FcγRs. To examine this, alloantibody-dependent hepatocyte rejection in CD8-depleted wild-type (WT) and Fcγ-chain knockout (KO; lacking all functional FcγR) transplant recipients was evaluated. Alloantibody-mediated hepatocellular allograft rejection was abrogated in recipients lacking FcγR compared with WT recipients. We also investigated anti-FcγRI mAb, anti-FcγRIII mAb, and inhibitors of intracellular signaling (to block phagocytosis, cytokines, and reactive oxygen species [ROS]) in an in vitro alloantibody-dependent, macrophage-mediated hepatocytoxicity assay. Results showed that in vitro alloantibody-dependent, macrophage-mediated hepatocytotoxicity was critically dependent on FcγRs and ROS. The adoptive transfer of WT macrophages into CD8-depleted FcγR-deficient recipients was sufficient to induce alloantibody-mediated rejection, whereas adoptive transfer of macrophages from Fcγ-chain KO mice or ROS-deficient (p47 KO) macrophages was not. These results provide the first evidence, to our knowledge, that alloantibody-dependent hepatocellular allograft rejection is mediated by host macrophages through FcγR signaling and ROS cytotoxic effector mechanisms. These results support the investigation of novel immunotherapeutic strategies targeting macrophages, FcγRs, and/or downstream molecules, including ROS, to inhibit humoral immune damage of transplanted hepatocytes and perhaps other cell and solid organ transplants., (Copyright © 2018 by The American Association of Immunologists, Inc.)

Neurodegenerative diseases are chronic and progressive disorders that affect specific regions of the brain, causing gradual disability and suffering that results in a complete inability of patients to perform daily functions. Amyloid aggregation of specific proteins is the most common biological event that is responsible for neuronal death and neurodegeneration in various neurodegenerative diseases. Therapeutic agents capable of interfering with the abnormal aggregation are required, but traditional drug discovery has fallen short. The exploration of new uses for approved drugs provides a useful alternative to fill the gap between the increasing incidence of neurodegenerative diseases and the long-term assessment of classical drug discovery technologies. Drug re-profiling is currently the quickest possible transition from bench to bedside. In this way, experimental evidence shows that some antibiotic compounds exert neuroprotective action through anti-aggregating activity on disease-associated proteins. The finding that many antibiotics can cross the blood-brain barrier and have been used for several decades without serious toxic effects makes them excellent candidates for therapeutic switching towards neurological disorders. The present review is, to our knowledge, the first extensive evaluation and analysis of the anti-amyloidogenic effect of different antibiotics on well-known disease-associated proteins. In addition, we propose a common structural signature derived from the antiaggregant antibiotic molecules that could be relevant to rational drug discovery., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The close relationship between protein aggregation and neurodegenerative diseases has been the driving force behind the renewed interest in a field where biophysics, neurobiology and nanotechnology converge in the study of the aggregate state. On one hand, knowledge of the molecular principles that govern the processes of protein aggregation has a direct impact on the design of new drugs for high-incidence pathologies that currently can only be treated palliatively. On the other hand, exploiting the benefits of protein aggregation in the design of new nanomaterials could have a strong impact on biotechnology. Here we review the contributions of our research group on novel neuroprotective strategies developed using a purely biophysical approach. First, we examine how doxycycline, a well-known and innocuous antibiotic, can reshape α-synuclein oligomers into non-toxic high-molecular-weight species with decreased ability to destabilize biological membranes, affect cell viability and form additional toxic species. This mechanism can be exploited to diminish the toxicity of α-synuclein oligomers in Parkinson's disease. Second, we discuss a novel function in proteostasis for extracellular glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in combination with a specific glycosaminoglycan (GAG) present in the extracellular matrix. GAPDH, by changing its quaternary structure from a tetramer to protofibrillar assembly, can kidnap toxic species of α-synuclein, and thereby interfere with the spreading of the disease. Finally, we review a brighter side of protein aggregation, that of exploiting the physicochemical advantages of amyloid aggregates as nanomaterials. For this, we designed a new generation of insoluble biocatalysts based on the binding of photo-immobilized enzymes onto hybrid protein:GAG amyloid nanofibrils. These new nanomaterials can be easily functionalized by attaching different enzymes through dityrosine covalent bonds.

Background: The liver immune environment is tightly regulated to balance immune activation with immune tolerance. Understanding the dominant immune pathways initiated in the liver is important because the liver is a site for cell transplantation, such as for islet and hepatocyte transplantation. The purpose of this study is to examine the consequences of alloimmune stimulation when allogeneic cells are transplanted to the liver in comparison to a different immune locale, such as the kidney., Methods: We investigated cellular and humoral immune responses when allogeneic hepatocytes are transplanted directly to the recipient liver by intraportal injection. A heterotopic kidney engraftment site was used for comparison to immune activation in the liver microenvironment., Results: Transplantation of allogeneic hepatocytes delivered directly to the liver, via recipient portal circulation, stimulated long-term, high magnitude CD8 T cell-mediated allocytotoxicity. CD8 T cells initiated significant in vivo allocytotoxicity as well as rapid rejection of hepatocytes transplanted to the liver even in the absence of secondary lymph nodes or CD4 T cells. In contrast, in the absence of recipient peripheral lymphoid tissue and CD4 T cells, CD8-mediated in vivo allocytotoxicity was abrogated, and rejection was delayed when hepatocellular allografts were transplanted to the kidney subcapsular site., Conclusions: These results highlight the CD8-dominant proinflammatory immune responses unique to the liver microenvironment. Allogeneic cells transplanted directly to the liver do not enjoy immune privilege but rather require immunosuppression to prevent rejection by a robust and persistent CD8-dependent allocytotoxicity primed in the liver., Competing Interests: The authors of this manuscript have no conflicts of interest to disclose.

Background: De novo alloantibodies (donor-specific antibody) contribute to antibody-mediated rejection and poor long-term graft survival. Because the development of donor-specific antibody is associated with early graft loss of cell transplants and reduced long-term survival of solid organ transplants, we hypothesized that conventional immunosuppressives, calcineurin inhibitors (CNi), and mammalian target of rapamycin inhibitors (mTORi), may not be as effective for suppression of humoral alloimmunity as for cell-mediated immunity., Methods: Wild-type or CD8-depleted mice were transplanted with allogeneic hepatocytes. Recipients were treated with mTORi and/or CNi and serially monitored for alloantibody and graft survival. The direct effect of mTORi and CNi on alloprimed B cell function was investigated in Rag1 mice adoptively transferred with alloprimed IgG1 B cells. The efficacy of mTORi and/or CNi to suppress CD8-mediated cytotoxicity of IgG1 B cells was evaluated in in vitro and in vivo cytotoxicity assays., Results: Mammalian target of rapamycin inhibitors, but not CNi, reduced alloantibody production in transplant recipients, directly suppressed alloantibody production by alloprimed IgG1 B cells and delayed graft rejection in both low and high alloantibody producers. Combination treatment with mTORi and CNi resulted in loss of the inhibitory effect observed for mTORi monotherapy in part due to CNi suppression of CD8 T cells which downregulate alloantibody production (CD8 TAb-supp cells)., Conclusions: Our data support that mTORi is a potent inhibitor of humoral immunity through suppression of alloprimed B cells and preservation of CD8 TAb-supp cells. In contrast, alloantibody is readily detected in CNi-treated recipients because CNi does not suppress alloprimed B cells and interferes with downregulatory CD8 TAb-supp cells., Competing Interests: The authors of this manuscript have no conflicts of interest to disclose.

Cholesterol from peripheral tissue, carried by HDL, is metabolized in the liver after uptake by the HDL receptor, SR-B1. Hepatocytes have long been considered the only liver cells expressing SR-B1; however, in this study we describe two disparate immunofluorescence (IF) experiments that suggest otherwise. Using high-resolution confocal microscopy employing ultrathin (120 nm) sections of mouse liver, improving z-axis resolution, we identified the liver sinusoidal endothelial cells (LSEC), marked by FcγRIIb, as the cell within the liver expressing abundant SR-B1. In contrast, the hepatocyte, identified with β-catenin, expressed considerably weaker levels, although optical resolution of SR-B1 was inadequate. Thus, we moved to a different IF strategy, first separating dissociated liver cells by gradient centrifugation into two portions, hepatocytes (parenchymal cells) and LSEC (non-parenchymal cells). Characterizing both portions for the cellular expression of SR-B1 by flow cytometry, we found that LSEC expressed considerable amounts of SR-B1 while in hepatocytes SR-B1 expression was barely perceptible. Assessing mRNA of SR-B1 by real time PCR we found messenger expression in LSEC to be about 5 times higher than in hepatocytes.

Some studies have reported a low rate of false recognition (FR) in individuals with autism spectrum disorder (ASD) relative to non-autistic comparison participants (CPs). This finding, however, has not always been replicated and the source of the discrepancy remains unknown. We hypothesised that poor episodic memory functions may account for this finding. We used an adapted version of the Deese, Roediger and McDermott paradigm which presents lists of words, pictures or word-picture pairs to obtain measures of performance which reflect episodic [hits and false alarms (FAs)] and semantic (FR) memory functions. Results showed a decreased rate of FR in ASD individuals with lists of words which rose above the rate seen in non-autistic CPs with lists of word-picture pairs. This increased rate of FR in ASD was accompanied by a parallel increase in hits and a decrease in FA which reached a similar level in the two groups. Poor episodic memory functions may prevent individuals with ASD from acquiring item information which in turn precludes the formation of semantic links between items. This could render them less prone to FR.

Growth hormone releasing peptide, GHRP-6, a hexapeptide (His-(D-Trp)-Ala-Trp-(D-Phe)-Lys-NH2, MW = 872.44 Da) that belongs to a class of synthetic growth hormone secretagogues, can stimulate growth hormone secretion from somatotrophs in several species including humans. In the present study, we demonstrate that GHRP-6 dispersed in aqueous solution, at pH 7.0, room temperature of 22 °C, is able to form long nanotubes, which is evidenced by combining small angle X-ray scattering (SAXS), transmission electron microscopy and molecular dynamics simulation results. Such nanotubes possess inner and outer cross-sections equal to 6.7(2) nm and 13.4(5) nm, respectively. The mechanism of peptide self-assembly was determined by molecular dynamics simulations revealing that the peptides self-assemble like amphiphilic molecules in aqueous solution in a partially interdigitated structure. In this case, the position of the positively charged amino terminus is located at the peptide-water interface, whereas the neutral NH2-capped carboxy terminus remains buried at the hydrophobic core. In contrast, the long side chain of Lys-6 stretches out of the hydrophobic core positioning its positive charge near the cylinder surface. The peptide configuration in the nanotube wall comes from the interplay between the hydrophobic interactions of the aromatic side chains of GHRP-6 and the electrostatic repulsion of its cationic charges. On increasing the peptide concentration, the long nanotubes self-arrange in solution displaying a bi-dimensional hexagonal-like packing in the SAXS curves, with a center-to-center distance of ∼15 nm. Further, we also show that the nanostructure formed in solution is quite stable and is preserved following transfer to a solid support.

Introduction: The Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP) are global measures of the maximal strength of the respiratory muscles., Objectives: To determine the values of MIP and MEP in healthy subjects aged 20 years old from the urban area of Manizales, Colombia and to correlate them with sociodemographic and anthropometric variables., Methods: This is an observational descriptive study. The population of the study was 203,965 healthy people from Manizales, a Colombian city located at 2,150 meters above sea level. The sample size was 308 subjects, selected using simple random sampling. The maximal respiratory pressures were determined in the sample chosen and were then considered according to the variables of age, gender, size, weight, Body Mass Index (BMI), and BMI classification. Finally a predictive model was created., Results: The average MIP value among the subjects of the study was 75±27 cmH20 and the MEP value was 96.4±36 cmH20. Both averages were higher in men than in women. Predictive equations were established for the normal values of MIP and MEP in healthy subjects; the best model for MIP was the resultant one among age, gender and BMI classification and for the MEP among gender, weight and height., Conclusion: Maximal respiratory pressure values were lower among the population of Manizales than those found in international studies. Gender and anthropometric characteristics (weight, height and BMI classification) are the explanatory variables that better support the average values of MIP and MEP in the predictive models proposed.

The 60's gave birth to the practical implementation of classical mechanics to unravel the dynamics and energetics of biomolecules. In the 70's the use of generalized force fields and more advanced integrative solutions to the microscopic understanding of nature (like hybrid QM/MM) were introduced. During the 80's, algorithms to obtain free energy values were further developed and in the 90's practical integration schemes of molecular mechanics force fields with other levels of detail (QM on one extreme and advances in implicit solvation on the other) were implemented in widely spread software. In the first decade of the XXIst century a considerable effort has been put in two seemingly discordant models for the simulation of biomolecules. On the one hand, extraordinary advances in computing technologies (both in terms of processor power and of new efficient parallel and distributed computing schemas) have allowed researchers to deal with bigger systems and longer simulations, reaching molecular processes including millions of particles or lying in the microsecond scale. On the other hand, the realization that the relevant answers to many biomolecular problems are not homogeneously distributed through the molecular structure, something already envisioned by the QM/MM pioneers more than three decades ago, has led researchers to find smart ways of putting different emphases on different ranges of the spatial or system time scale. In this context, e.g., molecular aggregation represents a paradigm for multiscalability, as molecular recognition can be understood with simple (semi-)macroscopic terms when the two fragments are far apart, while the atomic interactions need to be considered in full detail upon close distances. In this manuscript the current status of the techniques that use multiple scale representations of biomolecules are reviewed, and the findings are synthesized in a modular schema that can be extensively used when studying aggregation processes. It is shown that a smart alternative to brute force and massive computation of uninteresting regions in the all atom potential energy surface is the consideration of a simplified reference potential, explored thoroughly in the relevant regions, combined with a free energy perturbation approach that transforms this simple representation to a full atom representation.

Aims: To enumerate the micro-organisms and to identify the yeast species present during the ensilage of different sugarcane (Saccharum spp.) cultivars., Method: Samples of sugarcane silage were collected at 10, 20, 30 and 40 days from the start of fermentation. Population levels of lactic acid bacteria (LAB), mesophilic facultative anaerobic (MFA) bacteria, filamentous fungi and yeasts were determined. Nine species of yeasts were classified according to traditional methods and confirmed using molecular techniques., Conclusions: LAB dominated the ensiling process of sugarcane, although yeasts were present at relatively high population levels throughout the whole fermentation period. The detected species of yeasts varied according to sugarcane cultivar and time of fermentation. Torulaspora delbrueckii was the predominant yeast, followed by Pichia anomala and Saccharomyces cerevisiae., Significance and Impact of the Study: Knowledge of the population of micro-organisms in general, and of yeasts in particular, present during the fermentation of sugarcane is of fundamental importance in the development of more effective ensiling processes., (© 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.)

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a multifunctional enzyme related with Huntington's, Parkinson's and Alzheimer's diseases. The ability of negatively charged membranes to induce a rapid formation of GAPDH amyloid fibrils has been demonstrated, but the mechanisms by which GAPDH reaches the fibrillar state remains unclear. In this report, we describe the structural changes undergone by GAPDH at physiological pH and temperature conditions right from its interaction with acidic membranes until the amyloid fibril is formed. According to our results, the GAPDH-membrane binding induces a beta-structuring process along with a loss of quaternary structure in the enzyme. In this way, experimental evidences on the initial steps of GAPDH amyloid fibrils formation pathway are provided., (2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is considered a classical glycolytic protein that can promote the fusion of phospholipid vesicles and can also play a vital role on in vivo fusogenic events. However, it is not clear how this redox enzyme, which lack conserved structural or sequence motifs related to membrane fusion, catalyze this process. In order to detect if this ability is present in other NAD(P)H dehydrogenases with available structure, spectroscopic studies were performed to evaluate the capability of alcohol dehydrogenase (ADH), glutamic dehydrogenase (GDH) and sorbitol dehydrogenase (SDH) to bind, aggregate, destabilize and fuse vesicles. Based on finite difference Poisson-Boltzmann calculations (FDPB) the protein-membrane interactions were analyzed. A model for the protein-membrane complex in its minimum free energy of interaction was obtained for each protein and the amino acids involved in the binding processes were suggested. A previously undescribed relationship between membrane destabilization and crevices with high electropositive potential on the protein surface was proposed. The putative implication of the non-specific electrostatics on NAD(P)H dehydrogenases induced membrane fusion is discussed.

Background: The pyridine nucleotide disulfide reductase (PNDR) is a large and heterogeneous protein family divided into two classes (I and II), which reflect the divergent evolution of its characteristic disulfide redox active site. However, not all the PNDR members fit into these categories and this suggests the need of further studies to achieve a more comprehensive classification of this complex family., Results: A workflow to improve the clusterization of protein families based on the array of linear conserved motifs is designed. The method is applied to the PNDR large family finding two main groups, which correspond to PNDR classes I and II. However, two other separate protein clusters, previously classified as class I in most databases, are outgrouped: the peroxide reductases (NAOX, NAPE) and the type II NADH dehydrogenases (NDH-2). In this way, two novel PNDR classes III and IV for NAOX/NAPE and NDH-2 respectively are proposed. By knowledge-driven biochemical and functional data analyses done on the new class IV, a linear array of motifs putatively related to Cu(II)-reductase activity is detected in a specific subset of NDH-2., Conclusion: The results presented are a novel contribution to the classification of the complex and large PNDR protein family, supporting its reclusterization into four classes. The linear array of motifs detected within the class IV PNDR subfamily could be useful as a signature for a particular subgroup of NDH-2.

An 8-year-old boy presented with an asymptomatic intrascrotal epidermoid cyst with extension to deeper planes. Ultrasound examination showed no involvement of the testes or spermatic cord. Complete excision of the lesion was performed transcrotally. The histological examination of the lesion showed aspects with the same characteristics of epidermoid cysts found in the external genitalia.