RESUMO

In this work, an over-the-counter commercial dye, containing direct blue 151 in its composition, which is also discarded without any environmental regulation, was efficiency photodegraded using a green chemistry-synthesized nanocomposites type silver nanoparticles (AgNPs) supported on pistachio husk (PH). The green synthesis (GS) of the nanocomposites was carried out using the Anemopsis californica leaf extract (ExAc) as a reducing-stabilizing agent (AgNPs/ExAc-PH), for the first time. The presence of AgNPs on the nanocomposite surface was corroborated by field emission transmission electron microscope (FE-TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The synthesized AgNPs/ExAc-PH has a bimodal size of 24 and 25 nm (4.86 % each) and a 0.72 % of AgNPs on its surface. AgNPs were adhered to the PH surface, through secondary bonds between the Ag and the cellulose of the PH. The optimum conditions, for efficient photocatalytic degradation, were 5 mg of nanocomposite, 3.18 × 10-2 M of NaBH4, natural sunlight, and stirring; this results in a photodegradation efficiency of 100 % almost instantaneously. Furthermore, it was shown that the dye degradation process is primarily due to the photocatalytic degradation of the dye, which occurs almost instantaneously.

Assuntos

Nanopartículas Metálicas , Nanocompostos , Pistacia , Prata/química , Compostos Azo , Celulose , Nanopartículas Metálicas/química , Substâncias Redutoras , Nanocompostos/química , Extratos Vegetais/química , Antibacterianos/química

RESUMO

Primordial germ cells (PGCs) are embryonic pluripotent cells that can differentiate into spermatogonia and oogonia, and therefore, PGCs are a genetic source for germplasm conservation through cryobanking and the generation of germline chimeras. The knowledge of PGC migration routes is essential for transplantation studies. In this work, the mRNA synthesized from the ddx4 3'UTR sequence of Pseudopimelodus mangurus, in fusion with gfp or dsred, was microinjected into zygotes of three neotropical species (P. mangurus, Astyanax altiparanae, and Prochilodus lineatus) for PGC labeling. Visualization of labeled PGCs was achieved by fluorescence microscopy during embryonic development. In addition, ddx4 and dnd1 expressions were evaluated during embryonic development, larvae, and adult tissues of P. mangurus, to validate their use as a PGC marker. As a result, the effective identification of presumptive PGCs was obtained. DsRed-positive PGC of P. mangurus was observed in the hatching stage, GFP-positive PGC of A. altiparanae in the gastrula stage, and GFP-positive PGCs from P. lineatus were identified at the segmentation stage, with representative labeling percentages of 29% and 16% in A. altiparanae and P. lineatus, respectively. The expression of ddx4 and dnd1 of P. mangurus confirmed the specificity of these genes in germ cells. These results point to the functionality of the P. mangurus ddx4 3'UTR sequence as a PGC marker, demonstrating that PGC labeling was more efficient in A. altiparanae and P. lineatus. The procedures used to identify PGCs in P. mangurus consolidate the first step for generating germinal chimeras as a conservation action of P. mangurus.

RESUMO

Despite its rarity, symptomatic micronutrient deficiency remains a public health problem. Scurvy is the differential diagnosis for bleeding disorders and hematological and rheumatological diseases, especially in patients with eating disorders. However, it is unrelated to autism spectrum disorders or other neurodevelopmental disorders. A previously healthy 10-year-old boy living in São Paulo, Brazil, had a history of significant food selectivity unrelated to autism spectrum disorder, resulting in symptomatic ascorbic acid deficiency (scurvy). This resulted in pain and purpuric lesions on the lower limbs, gingival edema, bleeding during tooth brushing, asthenia, weakness, malaise, and sadness. Therefore, dietary anamnesis is important for routine monitoring of child growth and development. This process helps prevent nutritional deficiencies, facilitates early diagnosis of eating disorders, and enables multidisciplinary follow-up for these patients.

Assuntos

Transtorno do Espectro Autista , Desnutrição , Escorbuto , Masculino , Criança , Humanos , Escorbuto/complicações , Escorbuto/diagnóstico , Brasil , Diagnóstico Diferencial

RESUMO

The successful isolation of four new Neospora caninum strains from different regions and with different backgrounds (obtained from an abortion storm or congenitally infected and asymptomatic calves) allowed us previously to characterize natural isolates, finding differences in phenotype and microsatellites. Given the variability observed, we wondered in this work whether these differences had consequences in virulence, invasion and vertical transmission using cell cultures and murine neosporosis models. In addition, we performed the genomic analysis and SNP comparative studies of the NcURU isolates. The results obtained in this work allowed us to establish that NcURU isolates are of low virulence and have unique phenotypic characteristics. Likewise, sequencing their genomes has allowed us to delve into the genetic singularities underlying these phenotypes, as well as the common mutated genes. This work opens a new perspective for diagnostic purposes and formulating possible vaccines based on attenuated strains.

RESUMO

Biotechniques, including surrogate propagation derived from primordial germ cell (PGC) transplantation, are valuable tools for the reconstitution of endangered fish species. Although promising, there are no previous studies reporting such approaches using neotropical fish species. The aim of this study was to establish germline chimeras in neotropical fish by using the yellowtail tetra Astyanax altiparanae as a model species of the order Characiformes. Germline chimeras were obtained after transplantation of PGCs cultivated under different conditions: saline medium and supplemented with DMEM, amino acids, vitamins, glutamine, pyruvate, and fetal bovine serum, and subsequently transplanted into A. altiparanae triploids and triploid hybrids from the cross between A. altiparanae (♀) and A. fasciatus (♂). The results indicate ectopic migration in host embryos after transplantation of PGCs cultivated in saline medium. However, PGCs cultivated in supplemented medium migrated to the region of the gonadal ridge in 4.5% of triploid and 19.3% in triploid hybrid. In addition, the higher expression of dnd1, ddx4 and dazl genes was found in PGCs cultivated in supplemented culture medium. This indicates that the culture medium influences the maintenance and development of the cultivated cells. The expression levels of nanos and cxcr4b (related to the differentiation and migration of PGCs) were decreased in PGCs from the supplemented culture medium, supporting the results of ectopic migration. This is the first study to report the transplantation of PGCs to obtain germline chimera in neotropical species. The establishment of micromanipulation procedures in a model neotropical species will open new insights for the conservation of endangered species.

Assuntos

Caraciformes , Triploidia , Animais , Células Germinativas , Diferenciação Celular , Micromanipulação

RESUMO

ABSTRACT Despite its rarity, symptomatic micronutrient deficiency remains a public health problem. Scurvy is the differential diagnosis for bleeding disorders and hematological and rheumatological diseases, especially in patients with eating disorders. However, it is unrelated to autism spectrum disorders or other neurodevelopmental disorders. A previously healthy 10-year-old boy living in São Paulo, Brazil, had a history of significant food selectivity unrelated to autism spectrum disorder, resulting in symptomatic ascorbic acid deficiency (scurvy). This resulted in pain and purpuric lesions on the lower limbs, gingival edema, bleeding during tooth brushing, asthenia, weakness, malaise, and sadness. Therefore, dietary anamnesis is important for routine monitoring of child growth and development. This process helps prevent nutritional deficiencies, facilitates early diagnosis of eating disorders, and enables multidisciplinary follow-up for these patients.

RESUMO

The use of model organisms is important for basic and applied sciences. Several laboratory species of fishes are used to develop advanced technologies, such as the zebrafish (Danio rerio), the medaka (Oryzias latipes), and loach species (Misgurnus spp.). However, the application of these exotic species in the Neotropical region is limited due to differences in environmental conditions and phylogenetic distances. This situation emphasizes the establishment of a model organism specifically for the Neotropical region with the development of techniques that may be applicable to other Neotropical fish species. In this work, the previous research efforts are described in order to establish the yellowtail tetra Astyanax altiparanae as a model laboratory species for both laboratory and aquaculture purposes. Over the last decade, starting with artificial fertilization, the yellowtail tetra has become a laboratory organism for advanced biotechnology, such as germ cell transplantation, chromosome set manipulation, and other technologies, with applications in aquaculture and conservation of genetic resources. Nowadays, the yellowtail tetra is considered the most advanced fish with respect to fish biotechnology within the Neotropical region. The techniques developed for this species are being used in other related species, especially within the characins class.

RESUMO

Localization of single fluorescent molecules is key for physicochemical and biophysical measurements, such as single-molecule tracking and super-resolution imaging by single-molecule localization microscopy. Over the last two decades, several methods have been developed in which the position of a single emitter is interrogated with a sequence of spatially modulated patterns of light. Among them, the recent MINFLUX technique outstands for achieving a ∼10-fold improvement compared with wide-field camera-based single-molecule localization, reaching ∼1-2 nm localization precision at moderate photon counts. Here, we present a common framework for this type of measurement. Using the Cramér-Rao bound as a limit for the achievable localization precision, we benchmark reported methods, including recent developments, such as MINFLUX and MINSTED, and long-established methods, such as orbital tracking. In addition, we characterize two new proposed schemes, orbital tracking and raster scanning, with a minimum of intensity. Overall, we found that approaches using an intensity minimum have a similar performance in the central region of the excitation pattern, independent of the geometry of the excitation pattern, and that they outperform methods featuring an intensity maximum.

RESUMO

Primordial germ cells (PGCs) are responsible for generating all germ cells. Therefore, they are essential targets to be used as a tool for the production of germline chimeras. The labeling and route of PGCs were evaluated during the initial embryonic development of Pseudopimelodus mangurus, using whole-mount in situ hybridization (WISH) and mRNA microinjection in zygotes. A specific antisense RNA probe constituted by a partial coding region from P. mangurus nanos3 mRNA was synthesized for the WISH method. RNA microinjection was performed using the GFP gene reporter regulated by translation regulatory P. mangurus buc and nanos3 3'UTR sequences, germline-specific markers used to describe in vivo migration of PGCs. Nanos3 and buc gene expression was evaluated in tissues for male and female adults and initial development phases and larvae from the first to seventh days post-hatching. The results from the WISH technique indicated the origin of PGCs in P. mangurus from the aggregations of nanos3 mRNA in the cleavage grooves and the signals obtained from nanos3 probes corresponded topographically to the migratory patterns of the PGCs reported for other fish species. Diffuse signals were observed in all blastomeres until the 16-cell stage, which could be related to the two sequences of the nanos3 3'UTR observed in the P. mangurus unfertilized egg transcriptome. Microinjection was not successful using GFP-Dr-nanos1 3'UTR mRNA and GFP-Pm-buc 3'UTR mRNA and allowed the identification of potential PGCs with less than 2% efficiency only and after hatching using GFP-Pm-nanos3 3'UTR. Nanos3 and buc gene expression was reported in the female gonads and from fertilized eggs until the blastula phase. These results provide information about the PGC migration of P. mangurus and the possible use of PGCs for the future generation of germline chimeras to be applied in the conservation efforts of Neotropical Siluriformes species. This study can contribute to establishing genetic banks, manipulating organisms, and assisting in biotechnologies such as transplanting germ cells in fish.

Assuntos

Peixes-Gato , Feminino , Masculino , Animais , Regiões 3' não Traduzidas , Peixes-Gato/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Células Germinativas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Antissenso/metabolismo

RESUMO

Localization of single fluorescent emitters is key for physicochemical and biophysical measurements at the nanoscale and beyond ensemble averaging. Examples include single-molecule tracking and super-resolution imaging by single-molecule localization microscopy. Among the numerous localization methods available, MINFLUX outstands for achieving a ~10-fold improvement in resolution over wide-field camera-based approaches, reaching the molecular scale at moderate photon counts. Widespread application of MINFLUX and related methods has been hindered by the technical complexity of the setups. Here, we present RASTMIN, a single-molecule localization method based on raster scanning a light pattern comprising a minimum of intensity. RASTMIN delivers ~1-2 nm localization precision with usual fluorophores and is easily implementable on a standard confocal microscope with few modifications. We demonstrate the performance of RASTMIN in localization of single molecules and super-resolution imaging of DNA origami structures.

RESUMO

OBJECTIVE: To evaluate the associations of parent-reported sleep-disordered breathing (SDB) and device-assessed sleep behaviors with behavioral and emotional functioning in pediatric patients with overweight/obesity. STUDY DESIGN: A total of 109 children with overweight/obesity (mean age, 10.0 ± 1.1 years) were included in this cross-sectional study. We used the Spanish version of the Pediatric Sleep Questionnaire (PSQ) to assess SDB and its subscales (ie, snoring, daytime sleepiness, and inattention/hyperactivity). Device-assessed sleep behaviors (ie, wake time, sleep onset time, total time in bed, total sleep time, and waking after sleep onset) were estimated using wrist-worn accelerometers. We used the Behavior Assessment System for Children, second edition to assess behavioral and emotional functioning (ie, clinical scale: aggressiveness, hyperactivity, behavior problems, attention problems, atypicality, depression, anxiety, retreat, and somatization; adaptive scale: adaptability, social skills, and leadership). RESULTS: SDB was positively associated with all clinical scale variables (all ß > 0.197, P ≤ .041) and with lower adaptability and leadership (all ß < -0.226, P < .021). Specifically, the PSQ subscale relating to daytime sleepiness was associated with higher attention problems, depression, anxiety, and retreat (all ß > 0.196, P ≤ .045) and lower adaptability (ß = -0.246, P = .011). The inattention/hyperactivity subscale was significantly associated with the entire clinical and adaptive scales (all ß > |0.192|, P ≤ .046) except for somatization. The snoring subscale and device-assessed sleep behaviors were not related to any behavioral or emotional functioning variables. CONCLUSIONS: Our study suggests that SDB symptoms, but not device-assessed sleep behaviors, are associated with behavioral and emotional functioning in children with overweight/obesity. Specifically, daytime sleepiness, a potential SDB symptom, was related to higher attention problems, depression, anxiety, and retreat and lower adaptability.

Assuntos

Distúrbios do Sono por Sonolência Excessiva , Síndromes da Apneia do Sono , Criança , Estudos Transversais , Distúrbios do Sono por Sonolência Excessiva/complicações , Humanos , Obesidade/complicações , Sobrepeso/complicações , Sono , Síndromes da Apneia do Sono/complicações , Ronco/complicações , Inquéritos e Questionários

RESUMO

Triploidization plays an important role in aquaculture and surrogate technologies. In this study, we induced triploidy in the matrinxã fish (Brycon amazonicus) using a heat-shock technique. Embryos at 2 min post fertilization (mpf) were heat shocked at 38°C, 40°C, or 42°C for 2 min. Untreated, intact embryos were used as a control. Survival rates during early development were monitored and ploidy status was confirmed using flow cytometry and nuclear diameter analysis of erythrocytes. The hatching rate reduced with heat-shock treatment, and heat-shock treatments at 42°C resulted in no hatching events. Optimal results were obtained at 40°C with 95% of larvae exhibiting triploidy. Therefore, we report that heat-shock treatments of embryos (2 mpf) at 40°C for 2 min is an effective way to induce triploid individuals in B. amazonicus.

Assuntos

Caraciformes , Triploidia , Animais , Aquicultura , Resposta ao Choque Térmico , Humanos , Larva

RESUMO

Trypanosoma cruzi cytosolic tryparedoxin peroxidase (c-TXNPx) is a 2-Cys peroxiredoxin (Prx) with an important role in detoxifying host cell oxidative molecules during parasite infection. c-TXNPx is a virulence factor, as its overexpression enhances parasite infectivity and resistance to exogenous oxidation. As Prxs from other organisms possess immunomodulatory properties, we studied the effects of c-TXNPx in the immune response and analysed whether the presence of the peroxidatic cysteine is necessary to mediate these properties. To this end, we used a recombinant c-TXNPx and a mutant version (c-TXNPxC52S) lacking the peroxidatic cysteine. We first analysed the oligomerization profile, oxidation state and peroxidase activity of both proteins by gel filtration, Western blot and enzymatic assay, respectively. To investigate their immunological properties, we analysed the phenotype and functional activity of macrophage and dendritic cells and the T-cell response by flow cytometry after injection into mice. Our results show that c-TXNPx, but not c-TXNPxC52S, induces the recruitment of IL-12/23p40-producing innate antigen-presenting cells and promotes a strong specific Th1 immune response. Finally, we studied the cellular and humoral immune response developed in the context of parasite natural infection and found that only wild-type c-TXNPx induces proliferation and high levels of IFN-γ secretion in PBMC from chronic patients without demonstrable cardiac manifestations. In conclusion, we demonstrate that c-TXNPx possesses pro-inflammatory properties that depend on the presence of peroxidatic cysteine that is essential for peroxidase activity and quaternary structure of the protein and could contribute to rational design of immune-based strategies against Chagas disease.

Assuntos

Doença de Chagas/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Ativação Linfocitária , Peroxidases/metabolismo , Proteínas de Protozoários/metabolismo , Células Th1/metabolismo , Trypanosoma cruzi/enzimologia , Imunidade Adaptativa , Adulto , Idoso , Animais , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Feminino , Interações Hospedeiro-Parasita , Humanos , Imunidade Inata , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Mutação , Peroxidases/genética , Peroxidases/imunologia , Estrutura Quaternária de Proteína , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Relação Estrutura-Atividade , Células Th1/imunologia , Células Th1/parasitologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia

RESUMO

Fluorescence nanoscopy represented a breakthrough for the life sciences as it delivers 20-30 nm resolution using far-field fluorescence microscopes. This resolution limit is not fundamental but imposed by the limited photostability of fluorophores under ambient conditions. This has motivated the development of a second generation of fluorescence nanoscopy methods that aim to deliver sub-10 nm resolution, reaching the typical size of structural proteins and thus providing true molecular resolution. In this review, we present common fundamental aspects of these nanoscopies, discuss the key experimental factors that are necessary to fully exploit their capabilities, and discuss their current and future challenges.

RESUMO

We introduce p-MINFLUX, a new implementation of the highly photon-efficient single-molecule localization method with a simplified experimental setup and additional fluorescence lifetime information. In contrast to the original MINFLUX implementation, p-MINFLUX uses interleaved laser pulses to deliver the doughnut-shaped excitation foci at a maximum repetition rate. Using both static and dynamic DNA origami model systems, we demonstrate the performance of p-MINFLUX for single-molecule localization nanoscopy and tracking, respectively. p-MINFLUX delivers 1-2 nm localization precision with 2000-1000 photon counts. In addition, p-MINFLUX gives access to the fluorescence lifetime enabling multiplexing and super-resolved lifetime imaging. p-MINFLUX should help to unlock the full potential of innovative single-molecule localization schemes.

Assuntos

Nanotecnologia , Fótons , DNA , Lasers , Microscopia de Fluorescência

RESUMO

According to their oncogenic properties, Human Papillomaviruses (HPVs) are classified into two types: Low-Risk (LR-HPVs) and High-Risk Human Papillomaviruses (HR-HPVs). The immune system naturally controls the majority of HPV infections; however, when the HR-HPV infection is persistent, the risk of developing cervical cancer increases. Previous studies indicate that multiple-infection or coinfection with HR-HPV occurs frequently and can potentiate the development of cervical lesions. This study aimed to establish the HPV coinfection rate in squamous intraepithelial lesions from Mexican patients. For HPV detection, we performed PCR on 55 cervical lesions diagnosed by colposcopy. We detected the presence of HPV infection in 87.27% (48/55) of the lesions; interestingly, HPV coinfection was observed in 70.83% (34/48) of these samples. We also evaluated HPV infection in adjacent areas without morphological changes from 25 samples. The results showed that 80% (20/25) of these were HPV-positive and, curiously, all presented HPV-16 infection. In conclusion, our results revealed a high prevalence of HPV coinfection in cervical lesions in Mexican patients, and these results contribute to future research focused on the role that HPV coinfection plays in the development of cervical cancer.

Assuntos

Alphapapillomavirus/fisiologia , Coinfecção/virologia , Infecções por Papillomavirus/complicações , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Coinfecção/epidemiologia , Feminino , Humanos , México , Infecções por Papillomavirus/epidemiologia , Prevalência , Neoplasias do Colo do Útero/epidemiologia , Displasia do Colo do Útero/epidemiologia

RESUMO

Introducción: Las leucodistrofias primarias son un grupo de trastornos hereditarios que afectan la sustancia blanca cerebral de forma predominante. El término leucodistrofias primarias unifica las enfermedades que afectan las células gliales con compromiso de la mielina y el axón de base genética. Es un grupo de entidades, más de 30 en la actualidad, en expansión gracias a los avances en resonancia magnética y en genética. Objetivo: Contribuir al conocimiento de esta rara enfermedad con énfasis en la utilidad de su conocimiento clínico y en los estudios de imágenes evolutivos para el diagnóstico. Presentación del caso: Paciente con macrocranea detectada por la familia a los tres meses de nacida, al inicio refirieron que la circunferencia cefálica creció rápidamente y a partir del segundo semestre de vida el crecimiento se hizo más lento. La valoración clínica al año de edad comprobó una discreta dificultad para el control cefálico, intentaba dar pasos con apoyo, lenguaje de 3 a 4 palabras y ninguna otra afectación del neurodesarrollo. Al examen físico, una circunferencia cefálica de 55 cm (por encima de dos desviaciones estándar para la edad cronológica y sexo). Conclusiones: La evolución clínica favorable conjuntamente con el patrón de la resonancia magnética cerebral, que inicialmente mostró afectación de la sustancia blanca compatible con leucodistrofia inespecífica y en estudios evolutivos detecta presencia de quistes subtemporales, permitieron el diagnóstico de esta rara enfermedad infantil. La paciente recibió tratamiento sintomático para la espasticidad, apoyo pedagógico y control de sus crisis epilépticas(AU)

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Introduction: Primary leukodistrophies are a group of hereditary disorders that affect in a predominant way the white substance of the brain. The term ´´primary leukodistrophies´´ unifies the diseases that affect the glial cells compromising myelin and the genetic based axon. They are a group of entities, more tan 30 nowadays, which are expanding due to the advances in magnetic resonance and genetics. Objective: To contribute to the understanding of this rare disease with emphasis in the usefulness of its clinical knowledge and in the evolutive studies of images for diagnosis. Case presentation: Female patient with macrocranea detected by the family at 3 months old. At the beginning, the family referred that the cephalic circumference grew quickly and from the second semester of life growing process was slower. The clinical assessment at first year of life proved a discreet difficulty for cephalic control; the patient tried to do support footsteps, and had a language of 3 to 4 words without any other affectation in the neurodevelopment. In the physical examination, she presented a cephalic circumference of 55 cm (higher than the two stantard deviations for the cronological age and sex). Conclusiones: The clinical evolution was favorable jointly with the pattern of brain magnetic resonance that initially showed affectation in the white substance compatible with inespecific leukodistrophy and in the evolutive studies it was detected the presence of subtemporal cysts which allowed to diagnose this rare children disease. The patient received symptomatic treatment for spasticity, pedagogical support and control of the epileptic crisis(AU)

Assuntos

Humanos , Feminino , Lactente , Leucodistrofia de Células Globoides/diagnóstico por imagem

RESUMO

This study investigated the repertoire, call-type variability and call rates of southern right whales on a calving ground off Brazil in the western South Atlantic. Acoustic tag data were collected from four lactating females and one juvenile. Pulsive, hybrid, and upcalls showed the greatest variability among call-types with up to 23% of non-standard forms detected. Quiet sounds (grunt, single, and double pulse) were detected for the first time in this species on the calving grounds. Although the sample size was limited, results suggest that social interaction increased call-type diversity and call rates, in line with other acoustic studies on right whales.

Assuntos

Lactação , Baleias , Acústica , Animais , Brasil , Comunicação , Feminino

RESUMO

Single Molecule Localization Microscopy (SMLM) currently attains a lateral resolution of around 10 nm approaching molecular size. Together with increasingly specific fluorescent labeling, it opens the possibility to quantitatively analyze molecular organization. When the labeling density is high enough, SMLM provides clear images of the molecular organization. However, either due to limited labeling efficiency or due to intrinsically low molecular abundance, SMLM delivers a small set of sparse and highly precise localizations. In this work, we introduce a correlation analysis of molecular locations based on the functional dependence of the complementary cumulative distribution function (CCDF) of the distance to the first neighbor (r1). We demonstrate that the log(-log(CCDF(r1))) vs. log(r1) is characterized by a scaling exponent n that takes extreme values of 2 for a random 2D distribution and 1 for a strictly linear arrangement, and find that n is a robust and sensitive metric to distinguish characteristics of the underlying structure responsible for the molecular distribution, even at a very low labeling density. The method enables the detection of fibrillary organization and the estimation of the diameter of host fibers under conditions where a visual inspection provides no clue.