Morphological, histopathological, ultrastructural and phylogenetic analysis of Henneguya archosargus n. sp. (Cnidaria, Myxosporea) infecting the sparid fish Archosargus probatocephalus in Brazilian waters.

The introduction of new fish species to the aquaculture industry is essential to halt the progressive decline of natural fish stocks. The sheepshead Archosargus probatocephalus is a commercially valuable sparid fish with potential for breeding in captivity, but with limited information regarding parasitic infections that could pose a significant threat for its sustainable production. Thus, the present study aimed to study the myxozoan diversity infecting A. probatocephalus. A novel Henneguya sp. was detected forming plasmodia in the gill lamellae of specimens inhabiting the Brazilian coast, and is characterized based on morphological, histopathological, ultrastructural, molecular, and phylogenetic data. Myxospore total length was 21.3 ± 0.8 µm, with myxospore body 10.0 ± 0.5 µm long, 6.2 ± 0.3 µm wide, and 4.8 ± 0.5 µm thick. Caudal appendages were 10.3 ± 0.5 µm long and did not present any type of coating. Two pyriform polar capsules, 3.4 ± 0.3 µm long and 1.5 ± 0.2 µm wide, each containing an isofilar polar tubule with 4-5 coils. Histopathological analyses showed large intralamellar polysporic plasmodia associated with vascular congestion of the gill filament and gill lamellae, as well as epithelial hyperplasia causing partial or total fusion of gill lamellae. Maximum likelihood and Baysesian inference SSU rDNA-based phylogenetic analyses showed the novel sequence grouped within the marine clade of Henneguya spp. that mostly parasitize fishes belonging to Eupercaria incertae sedis.

Stellate Ganglion Block for Complex Regional Pain Syndrome Treatment After SARS-CoV-2 Vaccine: A Case Report.

Complex regional pain syndrome (CRPS) is a poorly understood neuropathic pain syndrome that may have different etiologies. Reports of this syndrome after vaccination are rare. We report a female patient with a medical history of acute stroke of the right carotid artery in the previous four months who developed hyperalgesia, allodynia, edema, and color changes in the upper left member compatible with CRPS one day after SARS-CoV-2 vaccination. A multimodal therapeutic approach was adopted, including a stellate ganglion block, with favorable results, including pain score reduction and increased mobility of the affected member.

All that glitters is not gold: a stereological study of human donor oocytes.

Here we report a quantitative analysis of human metaphase II (MII) oocytes from a 22-year-old oocyte donor, retrieved after ovarian-controlled hyperstimulation. Five surplus donor oocytes were processed for transmission electron microscopy (TEM), and a stereological analysis was used to quantify the distribution of organelles, using the point-counting technique with an adequate stereological grid. Comparisons between means of the relative volumes (Vv) occupied by organelles in the three oocyte regions, cortex (C), subcortex (SC) and inner cytoplasm (IC), followed the Kruskal-Wallis test and Mann-Whitney U-test with Bonferroni correction. Life cell imaging and TEM analysis confirmed donor oocyte nuclear maturity. Results showed that the most abundant organelles were smooth endoplasmic reticulum (SER) elements (26.8%) and mitochondria (5.49%). Significant differences between oocyte regions were found for lysosomes (P = 0.003), cortical vesicles (P = 0.002) and large SER vesicles (P = 0.009). These results were quantitatively compared with previous results using prophase I (GV) and metaphase I (MI) immature oocytes. In donor MII oocytes there was a normal presence of cortical vesicles, SER tubules, SER small, medium and large vesicles, lysosomes and mitochondria. However, donor MII oocytes displayed signs of cytoplasmic immaturity, namely the presence of dictyosomes, present in GV oocytes and rare in MI oocytes, of SER very large vesicles, characteristic of GV oocytes, and the rarity of SER tubular aggregates. Results therefore indicate that the criterion of nuclear maturity used for donor oocyte selection does not always correspond to cytoplasmic maturity, which can partially explain implantation failures with the use of donor oocytes.

The Overuse of the Emergency Department at a Multidisciplinary Pain Clinic by Patients with Chronic Pain: A Cross-Sectional Study.

Introduction Pain represents up to 78% of emergency department (ED) appointments, and an average of 16% of patients that consume ED resources have chronic pain. ED overuse could be an indicator of poor pain management. We are not aware of any study that has ever been carried out to understand the incidence of patients followed up at a multidisciplinary pain clinic (MPC) who overuse the ED. We aim to characterize patients in our MPC who overuse the emergency department, comprehend our percentages, and develop effective methods to reduce these numbers in the near future. Materials and methods We reviewed the medical records of patients observed in our MPC in 2019, selected patients with more than six ED visits from 2019 to 2021, and registered their ED visit diagnosis and evolution. We followed up on these patients and characterized them according to demographic aspects, chronic pain diagnostics, comorbidities, chronic medication, number of chronic pain department appointments, and patients that underwent invasive pain treatment. Results In 2019, 1892 patients were evaluated at our MPC, and only 1% were classified as overusers of the ED. The average number of episodes per patient was 10 in 2019, seven in 2020, and four in 2021. 70% of episodes were due to pain, and 94% were discharged immediately. The majority were women, and 69% were under the age of 69. Seventy-three percent had psychiatric disorders, and 95% and 89% were medicated with opioid and antidepressant medication, respectively, prior to the ED evaluation. Chronic primary pain was the most common diagnosis (47%), followed by chronic secondary musculoskeletal pain (21%). In 2019, most of these patients had only one appointment at our MPC, and in 2021, 79% had no appointments at all. Conclusion Our findings emphasize the particularities of patients with chronic pain who are followed in an MPC and misuse the ED. We observe the predominance of middle-aged people, which raises concerns about the impact of chronic pain in the active population. Issues like the predominance of patients with a diagnosis of primary chronic pain, psychiatric disorders, and being polymedicated with antidepressants and opioids are also a concern. We also realized that a high percentage of patients who overuse EDs lost follow-up at MPC over the past three years, which may reinforce the idea that they were misguided in the treatment of their chronic pain. We recognized the need to improve teamwork with primary care in the follow-up of these patients as well as sensitize emergency service professionals to refer this patient rather than medicate acutely so that follow-up could be carried out in the appropriate places to reduce the percentage of ED overuse.

(Re)imagining research, activism, and rights at the intersections of sexuality, health, and social justice.

The Covid-19 pandemic inaugurated a new global order of public life and health marked by death, despair and alienation. As a crisis of a global scale, it made the task of (re)imagination simultaneously necessary and extremely difficult. It is this double bind of the difficulty and imminence of imagination that motivates the curation of this special issue. In this introduction, we map the connections between the theme of this volume and the key ideas that constitute its varied contributions, which we organised under three broad mobilising ideas: Rights and Resilience; Sexuality, Health and Justice; and Politics of Knowledge Production and Collaborations. Contributions cover myriad issues, engage in methodological innovations and play with diverse genres. Alongside more traditional academic writings, there are community-based research papers, activist conversations, visual essays, reflective pieces and interviews. The geographical span of the contributions brings insights from around the world and the number of topics covered in this issue are equally vast including, among others, mental health, disability, environment, sex work, violence, queerness, LGBTQ+ experiences, love and anger. The aim of this special issue, then, is to challenge the Manichean distinctions that are often drawn between research and activism, and by extension, between theory and practice.

Hemagglutination in gill capillaries of sheepshead, Archosargus probatocephalus (Perciformes: Sparidae), infected by a myxosporidean.

During a survey Myxozoa, four specimens of the sheepshead (18 ± 1.5 cm and 59 ± 2.5 g) (Archosargus probatocephalus) were collected in the Ipioquinha river (Maceió/AL). Transmission electron microscopy observations revealed erythrocyte agglutinations in gill capillaries located near spherical cysts containing myxospores of the genus Henneguya. This hemagglutination partially or totally obstructed the gill capillaries. Erythrocytes occurred in close adherence to each other, with a closed intercellular space. A few lysed erythrocytes were observed among agglutinated cells. The reduced lumen of the capillaries was partially filled with amorphous dense homogenous material adhering to the erythrocytes. In addition, heterogeneous masses of irregular lower electron density were observed in the reduced channel of the capillary. The agglutinated erythrocytes appeared dense and homogenous, lacking cytoplasmic organelles. The nuclei had the appearance of normal condensed chromatin masses, generally without visible nucleoli. This occurrence of hemagglutination only in the capillaries located in close proximity to the developing myxozoan cysts suggests that parasite development may be a factor triggering erythrocyte agglutination. This is supported by previous experimental studies that showed a probable correlation between parasitic infections and hemagglutination. Nonetheless, further studies are necessary in order to better understand the physicochemical processes involved in this phenomenon.

Hemagglutination in gill capillaries of sheepshead, Archosargus probatocephalus (Perciformes: Sparidae), infected by a myxosporidean / Hemaglutinação em capilares branquiais de sargo-de-dente, Archosargus probatocephalus (Perciformes: Sparidae) infectado por um mixosporídeo

Abstract During a survey Myxozoa, four specimens of the sheepshead (18 ± 1.5 cm and 59 ± 2.5 g) (Archosargus probatocephalus) were collected in the Ipioquinha river (Maceió/AL). Transmission electron microscopy observations revealed erythrocyte agglutinations in gill capillaries located near spherical cysts containing myxospores of the genus Henneguya. This hemagglutination partially or totally obstructed the gill capillaries. Erythrocytes occurred in close adherence to each other, with a closed intercellular space. A few lysed erythrocytes were observed among agglutinated cells. The reduced lumen of the capillaries was partially filled with amorphous dense homogenous material adhering to the erythrocytes. In addition, heterogeneous masses of irregular lower electron density were observed in the reduced channel of the capillary. The agglutinated erythrocytes appeared dense and homogenous, lacking cytoplasmic organelles. The nuclei had the appearance of normal condensed chromatin masses, generally without visible nucleoli. This occurrence of hemagglutination only in the capillaries located in close proximity to the developing myxozoan cysts suggests that parasite development may be a factor triggering erythrocyte agglutination. This is supported by previous experimental studies that showed a probable correlation between parasitic infections and hemagglutination. Nonetheless, further studies are necessary in order to better understand the physicochemical processes involved in this phenomenon.

Resumo Durante pesquisa de mixozoários foram coletados quatro espécimes do peixes sargo-de-dente (18 ± 1.5 cm e 59 ± 2.5 g) (Archosargus probatocephalus), no rio Ipioquinha (Maceió/AL). Observações por microscopia eletrônica de transmissão revelaram aglutinação de eritrócitos em capilares branquiais localizados próximos a cistos esféricos, contendo mixosporos do gênero Henneguya. Essa hemaglutinação obstruiu parcial ou totalmente os capilares branquiais. Os eritrócitos apareceram em forte aderência entre si, com espaço intercelular fechado. Foram observados poucos eritrócitos lisados entre as células aglutinadas. O lúmen reduzido dos capilares foi parcialmente preenchido com material homogêneo denso amorfo aderido aos eritrócitos, além de massas livres heterogêneas de densidade eletrônica baixa e irregular observadas no canal reduzido dos capilares. Os eritrócitos aglutinados pareciam densos e homogêneos, sem organelas citoplasmáticas. Os núcleos apareceram como massas normais de cromatina condensada, geralmente sem nucléolos visíveis. A ocorrência de hemaglutinação apenas nos capilares, localizados nas proximidades dos cistos mixozoários, sugere que o desenvolvimento parasitário pode ser um fator desencadeante da aglutinação eritrocitária. Isso é corroborado por estudos experimentais anteriores que mostraram uma provável correlação entre infecções parasitárias e hemaglutinação. No entanto, novos estudos são necessários para melhor compreender os processos físico-químicos envolvidos neste fenômeno.

Functional morphology of the glandular esophageal pouches of chitons (Mollusca, Polyplacophora).

The esophageal pouches of Chaetopleura angulata and Acanthochitona fascicularis were investigated using light and transmission electron microscopy. These pouches linked to the posterior region of the esophagus are known as sugar glands as they contain a fluid rich in polysaccharide digesting enzymes. They are the second largest glands in the digestive system of chitons, just after the digestive gland. In both species, the pouches contain a dense array of finger-shaped villi. The villi epithelium includes absorptive cells, basophilic secretory cells, mucus-secreting cells, and basal cells. Some absorptive cells were bordered by a dense cover of long microvilli, whereas other absorptive cells had short and sparse microvilli. Absorptive cells contain several lysosomes, mitochondria, peroxisomes, a few small Golgi stacks, some lipid droplets, and large amounts of glycogen. The basophilic secretory cells are characterized by the presence of many electron-dense vesicles, with a glycoprotein content, a large number of rough endoplasmic reticulum cisternae, and a highly developed Golgi apparatus. Mucus-secreting cells are characterized by large vesicles containing acid polysaccharides and wide Golgi stacks. Basal cells that were found at the base of the epithelium in contact with the basal lamina exhibit histological and ultrastructural features of enteroendocrine cells. We suggest that these glandular pouches are involved in extracellular and intracellular digestion, and accumulate lipid and glycogen reserves.

Ultrastructure of intracytoplasmic Rickettsia-like infection of the gills of the teleost Archosargus probatocephalus (Sparidae) in northeastern Brazil.

A histopathological survey was conducted to investigate the presence of microparasites in fish Archosargus probatocephalus in a river near Maceió, Brazil. Light microscope observations of fragments of gill showed the presence of small cysts containing numerous myxospores that were morphologically identified as Henneguya. Transmission electron microscopy observations further revealed several gill cells containing groups of prokaryotic cells within large cytoplasmic vacuoles. Each infected host cell displayed a single vacuole containing a variable number of Rickettsia-like cells (up to 11), some of which presented the dumbbell shape characteristic of binary fission. The Rickettsia-like cells were pleomorphic, without a nucleus and with chromatin dispersed in the cytoplasm. They had a thin electron-dense wall of Gram-negative type. The morphology of these prokaryotic was similar to those of the order Rickettsiales and was described as a Rickettsia-like organism. Histopathological evaluation showed that several vacuole membranes had a lysed appearance. Some had ruptured, thus allowing direct contact between the Rickettsia-like organism and the cytoplasm of the host cell. The rupturing of the branchial epithelium may have contributed towards reduction of the surface area of the gills, but it is not possible to say that this was the cause of the host's death.

Stereological study of organelle distribution in human oocytes at metaphase I.

We have previously presented a stereological analysis of organelle distribution in human prophase I oocytes. In the present study, using a similar stereological approach, we quantified the distribution of organelles in human metaphase I (MI) oocytes also retrieved after ovarian stimulation. Five MI oocytes were processed for transmission electron microscopy and a classical manual stereological technique based on point-counting with an adequate stereological grid was used. Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction were used to compare the means of relative volumes (Vv) occupied by organelles. In all oocyte regions, the most abundant organelles were mitochondria and smooth endoplasmic reticulum (SER) elements. No significant differences were observed in Vv of mitochondria, dictyosomes, lysosomes, or SER small and medium vesicles, tubular aggregates and tubules. Significant differences were observed in other organelle distributions: cortical vesicles presented a higher Vv (P = 0.004) in the cortex than in the subcortex (0.96% vs 0.1%) or inner cytoplasm (0.96% vs 0.1%), vesicles with dense granular contents had a higher Vv (P = 0.005) in the cortex than in the subcortex (0.1% vs 0%), and SER large vesicles exhibited a higher Vv (P = 0.011) in the inner cytoplasm than in the subcortex (0.2% vs 0%). Future stereological analysis of metaphase II oocytes and a combined quantitative data of mature and immature oocytes, will enable a better understanding of oocyte organelle distribution during in vivo maturation. Combined with molecular approaches, this may help improve stimulation protocols and in vitro maturation methods.

Ultrastructure of intracytoplasmic Rickettsia-like infection of the gills of the teleost Archosargus probatocephalus (Sparidae) in northeastern Brazil / Ultraestrutura de Rickettsia intracitoplasmática infectando as brânquias do teleósteo Archosargus probatocephalus (Sparidae) no Nordeste do Brasil

Abstract A histopathological survey was conducted to investigate the presence of microparasites in fish Archosargus probatocephalus in a river near Maceió, Brazil. Light microscope observations of fragments of gill showed the presence of small cysts containing numerous myxospores that were morphologically identified as Henneguya. Transmission electron microscopy observations further revealed several gill cells containing groups of prokaryotic cells within large cytoplasmic vacuoles. Each infected host cell displayed a single vacuole containing a variable number of Rickettsia-like cells (up to 11), some of which presented the dumbbell shape characteristic of binary fission. The Rickettsia-like cells were pleomorphic, without a nucleus and with chromatin dispersed in the cytoplasm. They had a thin electron-dense wall of Gram-negative type. The morphology of these prokaryotic was similar to those of the order Rickettsiales and was described as a Rickettsia-like organism. Histopathological evaluation showed that several vacuole membranes had a lysed appearance. Some had ruptured, thus allowing direct contact between the Rickettsia-like organism and the cytoplasm of the host cell. The rupturing of the branchial epithelium may have contributed towards reduction of the surface area of the gills, but it is not possible to say that this was the cause of the host's death.

Resumo Um levantamento histopatológico foi realizado para pesquisar a presença de microparasitas, no peixe Archosargus probatocephalus, em um rio próximo a Maceió, Brasil. Observações ao microscópio óptico de fragmentos de brânquias mostraram a presença de pequenos cistos contendo numerosos mixósporos, identificados morfologicamente como Henneguya. Ocasionalmente, na microscopia eletrônica de transmissão, foram observados vários corpos citoplasmáticos de inclusão, grupo aparentemente de células procarióticas que vivem dentro de um grande vacúolo citoplasmático de algumas células branquiais. As células hospedeiras infectadas tinham um único vacúolo contendo um número variável de células do tipo Rickettsia, até 11, algumas das quais em forma do haltere, característica da fissão binária. Essas células eram pleomórficas sem núcleo, tendo a cromatina dispersa no citoplasma e possuíam uma parede densa de elétrons finos do tipo Gram-negativo. A morfologia dessas células procarióticas foi semelhante àquelas da ordem Rickettsiales e foram descritas como organismos tipo Rickettsiae. A histopatologia mostra várias membranas de vacúolos circundantes com aspetos lisados, enquanto outras apresentam rupturas que mostram contato direto do organismos tipo Rickettsiae com o citoplasma da célula hospedeira. A ruptura do epitélio branquial pode ter contribuído para a redução da superfície das brânquias, mas não é possível afirmar que foi a causa da morte do hospedeiro.

Clinical and Genetic Analysis of Children with Kartagener Syndrome.

Primary ciliary dyskinesia (PCD) is a rare autosomal recessive disorder characterized by dysfunction of motile cilia causing ineffective mucus clearance and organ laterality defects. In this study, two unrelated Portuguese children with strong PCD suspicion underwent extensive clinical and genetic assessments by whole-exome sequencing (WES), as well as ultrastructural analysis of cilia by transmission electron microscopy (TEM) to identify their genetic etiology. These analyses confirmed the diagnostic of Kartagener syndrome (KS) (PCD with situs inversus). Patient-1 showed a predominance of the absence of the inner dynein arms with two disease-causing variants in the CCDC40 gene. Patient-2 showed the absence of both dynein arms and WES disclosed two novel high impact variants in the DNAH5 gene and two missense variants in the DNAH7 gene, all possibly deleterious. Moreover, in Patient-2, functional data revealed a reduction of gene expression and protein mislocalization in both genes' products. Our work calls the researcher's attention to the complexity of the PCD and to the possibility of gene interactions modelling the PCD phenotype. Further, it is demonstrated that even for well-known PCD genes, novel pathogenic variants could have importance for a PCD/KS diagnosis, reinforcing the difficulty of providing genetic counselling and prenatal diagnosis to families.

Description of a new myxozoan Kudoa eugerres n. sp. and reclassification of two Sphaerospora sensu lato species.

Ultrastructural and phylogenetic description of a fish-infecting myxosporean found infecting the gallbladder wall of the teleostean Eugerres brasilianus Cuvier, 1830, collected from the Atlantic coast near the city of Maceió (Alagoas State), Brazil. Groups of mature pseudo-conical myxospores, agglutinated forming pseudocyst structures, occurring in the mucosa of gallbladder were 5.2 ± 0.8 µm (4.5-6.0) (n = 30) long, 4.3 ± 0.6 µm (3.8-4.7) (n = 25) thick, and 2.9 ± 0.2 µm (2.7-3.2) (n = 25) wide. The two ellipsoidal polar capsules, 1.8 ± 0.4 × 1.2 ± 0.4 µm (n = 25), opened close to the sutural line, each containing an isofilar polar tubule. The latter consisted of a single coil with five to six turns, arranged obliquely to the axis of the polar capsule. This myxosporean parasite, while being morphologically similar to Sphaerospora spp., displays tissue tropism and phylogenetic relationships distinct from the latter. Bayesian inference (BI) and maximum likelihood (ML) analyses showed the parasite and two other related species clustering within the marine clade, more specifically within a subclade of the larger Kudoa (Multivalvulida) clade. Consequently, this atypical new myxozoan species was classified as Kudoa eugerres n. sp. and two other histozoic Sphaerospora spp. sensu lato were transferred to the genus Kudoa.

Ultrastructure of phagocytes and oocysts of Nematopsis sp. (Apicomplexa, Porosporidae) infecting Crassostrea rhizophorae in Northeastern Brazil.

This work describes the detailed ultrastructural morphology of the phagocyte imprisoning an oyster of Nematopsis (Apicomplexa) found in Crassostrea rhizophorae, in the city of Maceió (AL), Brazil. The highly infected hosts had half-open leaflets with weak, slow retraction of the adductor muscles. Variable number of ellipsoid oocytes, either isolated and or clustered, was found between myofibrils of the adductor muscle. Each oocyst was incarcerated in a parasitophorous vacuole of host uninucleated phagocyte. The oocysts were composed of a dense wall containing a uninucleate vermiform sporozoite. The wall of the fine oocysts was composed of homogeneous electron-lucent material formed by three layers of equal thickness, having a circular orifice-micropyle obstructed by the operculum. The oocysts presented ellipsoid morphology with their wall was surrounded by a complex network of numerous microfibrils. Important details of the taxonomic value were visualized such as the ultrastructural organization of the oocyst wall and the organization of the micropyle and operculum, beyond the microfibrils that protrude from the oocyst wall only observed by transmission electron microscopy (TEM) and that may aid in the identification of the species. However, in order to clarify the systematic position of the species reported of the genus Nematopsis, it is important to proceed with genetic analyses.

Ultrastructure of phagocytes and oocysts of Nematopsis sp. (Apicomplexa, Porosporidae) infecting Crassostrea rhizophorae in Northeastern Brazil / Ultraestrutura de fagócitos e oocistos de Nematopsis sp. (Apicomplexa, Porosporidae) infectando Crassostrea rhizophorae no Nordeste brasileiro

Abstract This work describes the detailed ultrastructural morphology of the phagocyte imprisoning an oyster of Nematopsis (Apicomplexa) found in Crassostrea rhizophorae, in the city of Maceió (AL), Brazil. The highly infected hosts had half-open leaflets with weak, slow retraction of the adductor muscles. Variable number of ellipsoid oocytes, either isolated and or clustered, was found between myofibrils of the adductor muscle. Each oocyst was incarcerated in a parasitophorous vacuole of host uninucleated phagocyte. The oocysts were composed of a dense wall containing a uninucleate vermiform sporozoite. The wall of the fine oocysts was composed of homogeneous electron-lucent material formed by three layers of equal thickness, having a circular orifice-micropyle obstructed by the operculum. The oocysts presented ellipsoid morphology with their wall was surrounded by a complex network of numerous microfibrils. Important details of the taxonomic value were visualized such as the ultrastructural organization of the oocyst wall and the organization of the micropyle and operculum, beyond the microfibrils that protrude from the oocyst wall only observed by transmission electron microscopy (TEM) and that may aid in the identification of the species. However, in order to clarify the systematic position of the species reported of the genus Nematopsis, it is important to proceed with genetic analyses.

Resumo Este trabalho descreve a morfologia ultraestrutural detalhada do fagócito encarcerando um oocisto de Nematopsis (Apicomplexa) encontrado em Crassostrea rhizophorae, na cidade de Maceió (AL), Brasil. Os hospedeiros muito infectados apresentavam valvas entreabertas com retração fraca e lenta dos músculos abdutores. Número variável de oócitos de forma elipsoide, isolados e ou agrupados foi encontrado entre as miofibrilas do músculo abdutor. Cada oocisto estava encarcerado num vacúolo parasitóforo do fagócito uninucleado do hospedeiro. Os oocistos eram compostos por uma parede densa contendo um esporozoíto vermiforme uninucleado. A parede dos oocistos finos era composta de material electron-lucente homogêneo formado por três camadas de espessura igual, possuindo um orifício circular - micrópila, obstruída pelo opérculo. Os oocistos apresentavam morfologia elipsoide, sua parede era circundada por uma complexa rede de numerosas microfibrilas. Detalhes de valor taxonômico importantes foram visualizados tais como: a organização ultraestrutural da parede do oocisto e a organização da micrópila e do opérculo, além das microfibrilas que se projetam da parede do oocisto, estrutura apenas observada em microscopia eletrônica de transmissão (MET) e que pode auxiliar na identificação da espécie. Contudo, para esclarecer a posição sistemática da maioria das espécies relatadas do gênero Nematopsis é importante prosseguir com as análises genéticas.

Carbonic anhydrases are involved in mitochondrial biogenesis and control the production of lactate by human Sertoli cells.

The process that allows cells to control their pH and bicarbonate levels is essential for ionic and metabolic equilibrium. Carbonic anhydrases (CAs) catalyse the conversion of CO2 to HCO3- and H+ and are thus essential for this process. Herein, we inhibited CAs with acetazolamide - ACT and SLC-0111 - to study their involvement in the metabolism, mitochondrial potential, mitochondrial biogenesis and lipid metabolism of human Sertoli cells (hSCs), obtained from biopsies from men with conserved spermatogenesis. We were able to identify three isoforms of CAs, one mitochondrial isoform (CA VB) and two cell membrane-bound isoforms (CA IX and CA XII) in hSCs. When assessing the expression of markers for mitochondrial biogenesis, we observed a decrease in HIF-1α, SIRT1, PGC1α and NRF-1 mRNAs after all CAs were inhibited, resulting in decreased mitochondrial DNA copy numbers. This was followed by an increased production of lactate and alanine in the same conditions. In addition, consumption of glucose was maintained after inhibition of all CAs in hSCs. These results indicate a reduced conversion of pyruvate to acetyl-coA, possibly due to decreased mitochondrial function, caused by CA inhibition in hSCs. Inhibition of CAs also caused alterations in lipid metabolism, since we detected an increased expression of hormone-sensitive lipase (HSL) in hSCs. Our results suggest that CAs are essential for mitochondrial biogenesis, glucose and lipid metabolism in hSCs. This is the first report showing that CAs play an essential role in hSC metabolic dynamics, being involved in mitochondrial biogenesis and controlling lactate production.

Supplemental diagnosis and phylogeny of Myxobolus absonus (Cnidaria, Myxozoa) from the eye of the freshwater fish Pimelodus maculatus (Siluriformes, Pimelodidae).

Myxobolus absonusCellere et al., 2002 was originally described as having free cysts in the opercular cavity of the freshwater fish Pimelodus maculatus in Brazil. The present study provides a supplemental description of this parasite from the eye of its type host, with basis on morphological, ultrastructural, and molecular data of the SSU rRNA gene. The parasite formed spherical whitish cysts, which wall presented numerous microvilli that attached to the collagen layers of the corneal stroma. Myxospores were oval in valvular and sutural view, measuring 13.2 ± 0.4 µm in length, 8.5 ± 0.4 µm in width, and 6.6 ± 0.3 µm in thickness. Two asymmetric pyriform polar capsules were located at the anterior pole: the larger 6.2 ± 0.4 µm long and 3.6 ± 0.3 µm wide, containing a polar filament coiled in 6 turns; and the smaller 3.5 ± 0.3 µm long and 1.9 ± 0.1 µm wide, containing a polar filament coiled in 4 turns. At the posterior pole, the sporoplasm displayed two nuclei and numerous spherical sporoplasmosomes. Phylogenetic analysis using maximum likelihood, Bayesian inference and maximum parsimony revealed M. absonus clustering within a well-supported clade with poorly-resolved internal nodes, amongst the SSU rRNA sequences of other myxobolids that infect siluriform and characiform fish hosts, as well as the perciform-infecting species Myxobolus acanthogobii, Triangula percae and Cardimyxobolus japonensis. This clade appeared separated from the other clades comprising most of the species that infect siluriform and characiform hosts, showing that more than one myxobolid lineage evolved while parasitizing these taxonomic groups of fish.

Simultaneous occurrence of two new myxosporean species infecting the central nervous system of Hypopygus lepturus from Brazil.

This paper describes 2 new myxosporean species, Henneguya lepturus sp. nov. and Thelohanellus lepturus sp. nov., simultaneously infecting the brain and spinal cord of Hypopygus lepturus Hoedeman, 1962 (Teleostei, Hypopomidae) from the Brazilian Amazon (Roraima State). Several spherical cysts of varying dimensions (up to 135 µm) were microscopically observed. The myxospores of H. lepturus sp. nov. measured 25.8 µm in total length, having an ellipsoidal body (12.4 × 6.4 × 2.2 µm) and 2 equal tapering tails (13.4 µm in length). Each of the 2 pyriform polar capsules measured 4.4 × 1.6 µm and possessed a polar filament coiled in 8-9 turns. The myxospores of T. lepturus sp. nov. were pyriform, formed by 2 equal valves (17.7 × 9.1 × 4.3 µm) surrounding a single polar capsule (10.9 × 3.5 µm) that had a coiled polar filament with 13-16 turns and a binucleated sporoplasm that contained several circular sporoplasmosomes. Molecular analysis of the small subunit (SSU) rRNA gene sequences of these 2 species were in agreement with the taxonomic classification derived from the ultrastructure of the myxospores. Histopathology of the host tissue showed degradation of the myelinated axons surrounding the cysts of both species, with the hosts displaying behavioural changes and erratic movements when observed in an aquarium.

Mannitol oxidase and polyol dehydrogenases in the digestive gland of gastropods: Correlations with phylogeny and diet.

Mannitol oxidase and polyol dehydrogenases are enzymes that convert polyalcohols into sugars. Mannitol oxidase was previously investigated in terrestrial snails and slugs, being also present in a few aquatic gastropods. However, the overall distribution of this enzyme in the Gastropoda was not known. Polyol dehydrogenases are also poorly studied in gastropods and other mollusks. In this study, polyalcohol oxidase and dehydrogenase activities were assayed in the digestive gland of 26 species of gastropods, representing the clades Patellogastropoda, Neritimorpha, Vetigastropoda, Caenogastropoda and Heterobranchia. Marine, freshwater and terrestrial species, including herbivores and carnivores were analyzed. Ultrastructural observations were undertake in species possessing mannitol oxidase, in order to investigate the correlation between this enzyme and the presence of tubular structures known to be associated with it. Mannitol oxidase activity was detected in the digestive gland of herbivores from the clades Caenogastropoda and Heterobranchia, but not in any carnivores or in herbivores from the clades Patellogastropoda, Neritimorpha and Vetigastropoda. In most of the species used in this study, dehydrogenase activities were detected using both D-mannitol and D-sorbitol as substrates. Nevertheless, in some carnivores these activities were not detected with both polyalcohols. Ultrastructural observations revealed tubular structures in digestive gland cells of some species having mannitol oxidase activity, but they were not observed in others. Based on our results, we suggest that mannitol oxidase first occurred in a herbivorous or omnivorous ancestor of Apogastropoda, the clade formed by caenogastropods and heterobranchs, being subsequently lost in those species that shifted towards a carnivorous diet.