Adriana Ventura

Metal homeostasis plays a fundamental role in retinal physiology, yet the spatial organization of biologically relevant elements within retinal tissue remains incompletely understood, particularly at cellular and subcellular scales. In this study, we investigated the elemental composition and ultrastructural organization of the light-adapted retina of the cycloramphid frog Thoropa miliaris at different developmental stages using synchrotron-based X-ray fluorescence microscopy (XRF) and ptychographic imaging. High-resolution elemental maps were acquired at the CARNAÚBA beamline (Sirius, Brazil) and the TwinMic beamline (Elettra Sincrotrone Trieste, Italy), enabling the characterization of both low- and high-Z elements. Distinct distribution patterns were observed among retinal layers, with higher concentrations of several elements in metabolically active regions such as the retinal pigment epithelium. Elemental ratio maps (Fe/Cu and Fe/Mn) provided additional information regarding retinal metal homeostasis and showed consistent spatial patterns across developmental stages, synchrotron facilities, and excitation energies. To investigate the relationship between elemental localization and structural contrast, osmium, iodine, and phosphotungstic acid (PTA) staining protocols were evaluated using ptychographic imaging. Each contrast agent exhibited distinct retinal localization patterns and selectively enhanced different anatomical features. Osmium preferentially highlighted membrane-rich photoreceptor regions, iodine improved visualization of cellular nuclei and intralayer organization, and PTA enhanced protein-rich and synaptic structures. The results demonstrate the complementary capabilities of XRF and ptychography for the multimodal characterization of retinal tissue. This approach provides new insights into elemental organization in the amphibian retina and establishes a methodological framework for future investigations of retinal development, metal homeostasis, and disease-related alterations.

We assessed the effect of the entomopathogenic fungus Metarhizium anisopliae against Aedes aegypti. Conidia of M. anisopliae strains CG 489, CG 153, and IBCB 481 were grown in Adamek medium under different conditions to improve blastospore production. Mosquito larvae were exposed to blastospores or conidia of the three fungal strains at 1 × 10⁷ propagules mL⁻¹. M. anisopliae IBCB 481 and CG 153 reduced larval survival by 100%, whereas CG 489 decreased survival by about 50%. Blastospores of M. anisopliae IBCB 481 had better results in lowering larval survival. M. anisopliae CG 489 and CG 153 reduced larval survival similarly. For histopathology (HP) and scanning electron microscopy (SEM), larvae were exposed to M. anisopliae CG 153 for 24 h or 48 h. SEM confirmed the presence of fungi in the digestive tract, while HP confirmed that propagules reached the hemocoel via the midgut, damaged the peritrophic matrix, caused rupture and atrophy of the intestinal mucosa, caused cytoplasmic disorganization of the enterocytes, and degraded the brush border. Furthermore, we report for the first time the potential of M. anisopliae IBCB 481 to kill Ae. aegypti larvae and methods to improve the production of blastospores.

Background: Cutaneous lymphoma is a highly malignant neoplasm, which can originate in the epidermis or dermis, as well as be disseminated to other organs such as lung, heart, arm, liver and bone marrow. It comes in the form of nodes of various sizes, erythematous and alopecic, itching may or may not occur. The diagnosis is made by cytological and histopathological examination of the compromised tissue. However, it is important to perform complementary tests for clinical staging and prognostic characterization. The objective is to report a case of non-epitheliotropic cutaneous lymphoma with systemic dissemination in a dog. Case: A female mixed bred adult canine was attended at the Veterinary Hospital of the Federal University of Mato Grosso do Sul with a history of progressive weight loss and the presence of alopecic and non-pruritic subcutaneous nodules in the torso, nasal plane and pelvic limbs, starting 4 months ago. After approximately 20 days, the presence of rapidly evolving ulcerated nodules was noted. On physical examination, generalized lymphadenomegaly was observed and among the dermatological findings were multiple nodules of varying sizes with the presence of ulceration in the center of the lesions, alopecia, erythema and raised edges, in the region of the nasal sinus, pelvic and thoracic limbs, tail, thoracolumbar and abdominal region. The animal also presented right pelvic limb edema with painful sensibility to manipulation CBC and biochemical tests (albumin, alanine aminotransferase, creatinine, urea, alkaline phosphatase, globulins, total proteins and fractions) were performed, being observed as normocytic normochromic type anemia alteration (erythrocytes: 2.78 106/µL; hemoglobin: 6.8 g/µL; globular volume: 18.8%), leukopenia (4,000/mm³) with presence of metamyelocytes (120/mm³) and rods (1,080/mm³) and lymphopenia (80/mm³). Three samples of the nodules were collected for histopathological examination and a definitive diagnosis of cutaneous lymphoma was obtained. The material was then submitted to immunohistochemical examination, which showed that it was a non-epitheliotropic cutaneous lymphoma of T immunophenotype. Due to the compromised quality of life and unfavorable prognosis, the owner opted for euthanasia of the animal. In the necropsy examination, lymph nodes, subcutaneous tissue, skeletal muscle, heart, pericardial sac, tongue and multifocal infiltrate of neoplastic cells were observed, findings suggestive of multicentric lymphoma or infiltrations by dissemination of cutaneous lymphoma. Discussion: Non-epitheliotropic skin lymphomas exhibit rapid progression and infiltration into lymph nodes and subsequent systemic involvement. The diagnosis is based on clinical-dermatological signs, fine needle cytology, histopathological and immunohistochemical examination. Normocytic normochromic anemia is the most observed alteration in patients with lymphoma, followed by leukocytosis, leukopenia, thrombocytopenia, neutrophilia and leukoerythroblastic reactions. Dogs with T-cell lymphoma have a worse prognosis for life span and disease-free intervals than those with B-cell lymphoma, so immunophenotyping is critical to determine prognosis. In the present report, histopathological and immunohistochemical examinations were decisive for the diagnosis of the present report, because the expression CD3 and the negativity for CD79a proved that the neoplasm is of T lymphocyte lineage. The definitive diagnosis was obtained by histopathology, however, immunohistochemistry determined the immunophenotype of the neoplasia as non-epitheliotropic T lymphocyte.

Summary: Conjoined twinning is an embryological anomaly rarely reported in wild mammals and with only two previous records in Chiroptera. Here, we report a case of dicephalic parapagus conjoined twins in the Neotropical phyllostomid genus Artibeus. These twins are males and present separated heads and necks, but a conjoined trunk with an expanded upper thoracic region. They developed two complete forelimbs and two complete hindlimbs, all laterally to the trunk. There is a volume in the upper midback and between the heads that resembles a third rudimentary medial forelimb, but X‐ray images only suggest the presence of medial skeletal elements of the pectoral girdle (clavicle and scapulae) in this region. The X‐ray images also show that vertebral columns run separated from head until the base of lumbar region, where they form a single structure. Using ultrasound images, we detected the presence of two similarly sized and apparently separated hearts. The accumulation of study cases like this will help in the understanding of patterns and process behind this phenomena, and collection material plays a key role in this context.

Phrynops geoffroanus é o quelônio onívoro com mais ampla distribuição geográfica na América do Sul. Este trabalho descreve a histologia e histoquímica do tubo digestório desta espécie, relacionando as características dos órgãos com seu hábito alimentar. O esôfago, estômago e intestino de quatro espécimes foram fixados em formol 10% e incluídos em parafina por técnica histológica de rotina. Depois, cortes de 5 µm de espessura foram corados com hematoxilina-eosina (HE), ácido periódico de Schiff (PAS) e alcian blue (AB) pH 0.4 e 2.5. O tubo é formado pelas camadas mucosa, submucosa, muscular e adventícia ou serosa. A mucosa do esôfago e do estômago é revestida pelo epitélio simples cilíndrico com células mucossecretoras, onde estão inseridas glândulas intraepiteliais na porção do esôfago e fossetas gástricas desembocando em glândulas no estômago. O estômago divide-se em anterior, médio e posterior, de acordo com a profundidade das fossetas e a concentração de glândulas gástricas. O intestino é revestido pelo epitélio simples cilíndrico com borda estriada e células caliciformes e divide-se em anterior e posterior, de acordo com o padrão de dobramentos da mucosa e o número de células caliciformes. Reatividade ao PAS e AB é observada em todo o tubo. Fibras musculares lisas estão presentes na camada mucosa de todos os segmentos. A camada muscular é formada por duas subcamadas de músculo liso, exceto na porção posterior do estômago. Este estudo ajudará no entendimento da fisiologia digestiva da espécie investigada e fornecerá dados para análises comparativas com outros quelônios.

Ontogenesis comprises a series of events including cell proliferation and apoptosis and resulting in the normal development of the embryo. Protein p53 has been described as being involved in the development of several animal species. The aim of this study was to analyze the expression of protein p53 during the morphogenesis of the gastroesophageal mucosa of Gallus gallus domesticus and to correlate it with the histogenesis of structures present in this tissue. We used 24 embryos (at 12–20 days of incubation) and the thymus of two chickens. Immunohistochemical analysis was performed with the ABC indirect method. The expression of p53 in the gastroesophageal mucosa increased during the formation of the organ, mainly at the stages during which tissue remodeling and cell differentiation began. In the esophagus at stages 42 and 45, we observed immunoreactive (IR) cells in the surface epithelium and in early esophageal glands. In the proventriculus at stages 39–45, IR cells were present in the epithelial mucosa and rarely in the proventricular glands. In the gizzard after stage 42, we found IR cells mainly in the medial and basal epithelial layers of the mucosa and especially within the intercellular spaces that appeared at this phase and formed the tubular gland ducts. Thus, protein p53 occurs at key stages of development: in the esophagus during the remodeling of esophageal glands, in the proventriculus during the differentiation of the epithelium of the mucosa and in the gizzard during the formation of tubular glands.