An overview of functional and stereological evaluation of spermatogenesis and germ cell transplantation in fish

Although there are almost thirty-thousand species of fish living in a great variety of habitats and utilizing vast reproductive strategies, our knowledge of morphofunctional and quantitative aspects of testis structure and spermatogenesis is still incipient for this group of vertebrates. In this review, we discuss aspects that are important to better understanding of testis structure and function, and of the development of germ cells (GC) during spermatogenesis. To achieve this, we have recently completed a number of studies presenting morphometric and functional data related to the numbers of GC and Sertoli cells (SC) per each type of spermatogenic cyst, the number of spermatogonial generations, the SC efficiency, and the magnitude of GC loss that normally occurs during spermatogenesis. We also investigated SC proliferation and the relationship of this important event to early spermatogenic cysts. The available data strongly suggest that SC proliferation in sexually mature tilapia is the primary factor responsible for the increase in testis size and for determination of the magnitude of sperm production. The influence of temperature on the duration of spermatogenesis in tilapia was also evaluated and we have used this knowledge to deplete endogenous spermatogenesis in this teleost, in order to develop an experimental system for GC transplantation. This exciting technique results in new possibilities for investigation of spermatogenesis and spermatogonial stem cell biology, creating also an entirely new and promising scenario in biotechnology - transgenic animal production and the preservation of the genetic stocks of valuable animals or endangered species. © Springer Science+Business Media B.V. 2008.

Cell junctions in fish seminiferous epithelium

Similar to mammals, in fish the cellular interactions between Sertoli cells (SC) and germ cells (GC) in the seminiferous epithelium have important structural and functional roles. In this review, we give a brief summary of these interactions, in particular those on the cell junctions. Despite the scarcity of detailed empirical data, it appears that both basic types of adhesive junctions (actin- and intermediate filaments-related) are present between SC. However, the actin-related multifunctional junction known as the ectoplasmic specialization is seemingly present only in some cartilaginous fish. Conversely, SC in other fish species are joined by actin-related junctions similar to typical zonulae or puncta adherens found in other epithelia. Adhesive junctions are also found between SC and GC and between GC and GC, and due to their particular characteristics these junctions are known as desmosome-like junctions. In terms of intercellular communication, connexins and gap junctions have been shown to occur between SC in fish, and they may be involved in the coordination of the synchronous development of GC within the cysts. It is also possible that gap junctions may form an interconnected network between SC and GC within a cyst. Concerning the SC barrier, tight junctions between fish SC apparently form a functional barrier only in cysts containing haploid GC, and different from mammals, meiotic GC in fish are not shielded from the vascular system. In summary, although still not well investigated, cell-cell interactions in the seminiferous epithelium of fish seem to be crucial for GC development, and their disturbance, for example by changing environmental conditions, will probably affect GC survival and fertility. © Springer Science+Business Media B.V. 2008.

Congenital ranula: A case report

The purpose of this study was to report a case of bilateral swelling on the floor of the mouth of a 7-month-old patient. The lesion was congenital and had started to cause feeding problems. After the clinical diagnosis of ranula was made, the lesion was marsupialized. The obtained specimen was submitted for histopathological examination, which revealed an epithelial-lined cystic lesion. These results led to the final diagnosis of mucus retention cyst. After an 8-year follow-up period, the patient is in good general health with no recurrences.

Bovine abortion associated with Neospora caninum: Diagnosis and epidemiological aspects of a dairy cattle herd in the northeast region of São Paulo state, Brazil

The objective of this study was to report the presence of Neospora caninum-associated abortion in bovines at a farm in the northeast region of São Paulo State. In January 2010, it was sent to the Department of Pathology, UNESP-Jaboticabal, a bovine fetus with an estimated age of seven months, which was natural of a dairy farm with 300 animals and an average daily production of 3,000 liters of milk, nearly 20 liters per cow. The animals were vaccinated against rabies, foot and mouth disease, carbuncle, brucellosis, leptospirosis, bovine herpes virus type I and bovine viral diarrhea virus. The herd consisted of purebred Holstein animals, Jersey, and mostly by crossbred animals 7-8 (gir x holstein). During necropsy, samples of the serosanguineous liquid present at the thoracic cavity and the heart of the fetus were collected for the detection of anti-Neospora caninum antibodies through Indirect Immunofluorescence Assay (IFA). Fragments of brain, cerebellum, tongue, liver, heart and kidneys were collected for the execution of histopathology (HP), immunohistochemistry (IHC) and Polymerase Chain Reaction. In order that IFA could be performed, the owner was requested blood samples without anticoagulants of the mother and other cows in the farm, with or without a history of abortion. At necropsy, it was verified a severe autolysis of the fetus. The serology of the fetus was 1:25, while the serology of the mother was 1:3,200. At HP, it was observed discrete multifocal non-suppurative encephalomyelitis characterized by gliosis and mononuclear inflammatory infiltration associated with cellular debris. DNA amplification of N. caninum was positive in fragments of brain, tongue, cerebellum, heart and kidneys. At IHC, it has been observed immunoreactivity to a cyst located in the tongue. The owner reported that his herd showed endemic episodes of abortion, while 27.69% (18/65) of the 65 animals sampled were seropositive. Although it has not been a significant difference (p>0.05), a higher seropositivity was observed in animals with a history of abortion (10/26) 38.46%, in comparison with animals without previous abortion (8/39) 20.51%. These findings show that the abortion under study was provoked by the protozoan N. caninum, while this is the first report concerning cattle in the northeast region of São Paulo State.

Neurocysticercosis: The enigmatic disease

Neurocysticercosis (NCC) is an infection of the central nervous system (CNS) caused by the metacestode larval form of the parasite Taenia sp. Many factors can contribute to the endemic nature of cysticercosis. The inflammatory process that occurs in the tissue surrounding the parasite and/or distal from it can result from several associated mechanisms and may be disproportionate with the number of cysts. This discrepancy may lead to difficulty with the proper diagnosis in people from low endemic regions or regions that lack laboratory resources. In the CNS, the cysticerci have two basic forms, isolated cysts (Cysticercus cellulosae = CC) and racemose cysts (Cysticercus racemosus = CR), and may be meningeal, parenchymal, or ventricular or have a mixed location. The clinical manifestations are based on two fundamental syndromes that may occur in isolation or be associated: epilepsy and intracranial hypertension. They may be asymptomatic, symptomatic or fatal; have an acute, sub-acute or chronic picture; or may be in remission or exacerbated. The cerebrospinal fluid (CSF) may be normal, even in patients with viable cysticerci, until the patients begin to exhibit the classical syndrome of NCC in the CSF, or show changes in one or more routine analysed parameters. Computed tomography (CT) and magnetic resonance imaging (MRI) have allowed non-invasive diagnoses, but can lead to false negatives. Treatment is a highly controversial issue and is characterised by individualised therapy sessions. Two drugs are commonly used, praziquantel (PZQ) and albendazole (ABZ). The choice of anti-inflammatory drugs includes steroids and dextrochlorpheniramine (DCP). Hydrocephalus is a common secondary effect of NCC. Surgical cases of hydrocephalus must be submitted to ventricle-peritoneal shunt (VPS) immediately before cysticidal treatment, and surgical extirpation of the cyst may lead to an absence of the surrounding inflammatory process. The progression of NCC may be simple or complicated, have remission with or without treatment and may exhibit symptoms that can disappear for long periods of time or persist until death. Unknown, neglected and controversial aspects of NCC, such as the impaired fourth ventricle syndrome, the presence of chronic brain oedema and psychic complaints, in addition to the lack of detectable glucose in the CSF and re-infection are discussed. © 2011 Bentham Science Publishers.

Comparative embryology and taxonomic considerations in Eriocaulaceae (Poales)

The genus concept within Eriocaulaceae is widely discussed because it is mainly based on a small number of floral characteristics of unknown functional and evolutionary significance. The aim of the present work is to comparatively study the embryology of representatives of most genera of Eriocaulaceae to identify relevant features that might aid in circumscribing them. In Eriocaulaceae, the uniformity of the embryological characteristics makes it difficult to interpret the existing relationships among the genera. Some embryological characteristics, especially those related to the number of microsporangia, are shown to be unstable and restricted to Paepalanthoideae. The unique pollen morphology may be related to mechanical processes to accommodate the increase in volume after early formation of the pollen wall and may indicate a relationship to an inaperturate ancestor. The placentation, formerly stated to be axile, is more likely to be central due to protusions of the locular base. The shape of the proximal region of the megagametophyte may be responsible for the formation of the antipodal cyst. The seed coat structure is uniform in origin and is a consistent taxonomic characteristic of the family. A review of Eriocaulaceae is necessary, in which additional morphological and anatomical characteristics should be considered and combined. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Unusually rapid growth of brown tumour in the mandible after parathyroidectomy associated with the presence of a supernumerary parathyroid gland

The aim of this study is to report the case of a quick growing brown tumour in the jaw after a parathyroidectomy due to the presence of a rare fifth parathyroid gland. The patient had chronic renal disease and the diagnosis was tertiary hyperparathyroidism. Thirty days after the parathyroidectomy, the patient returned with a significant increase in the tumour size. The suspicion of a supernumerary gland was confirmed by parathyroid scintigraphy. The treatment of brown tumour is dependent on the treatment of the hyperparathyroidism. However, curettage should be considered if a large lesion is disturbing mastication. In conclusion, this case should attract the attention of general practitioner dentists, since they may be the first professionals who have contact with the patient with a brown tumour in the jaws. Likewise, this case emphasises the importance of knowing the type of hyperparathyroidism involved to allow for effective treatment planning. © 2011 European Association for Cranio-Maxillo-Facial Surgery.

Noninvasive aspergillosis as a maxillary antrolith: report of a rare case.

Maxillary antrolithiasis is characterized by masses of tissue of endogenous or exogenous origin that calcify within the maxillary sinuses. Aspergillosis is a fungal disease in which the maxillary sinus is a primary site of infection. Aspergillosis mycetoma, its noninvasive form, is the most prevalent modality of the disease in the maxillary sinuses. In approximately half of the cases reported in the literature, calcification of the fungal mycelia, which later became antroliths, was verified. This article reports a rare case of the accidental discovery of a maxillary antrolith associated with noninvasive aspergillosis in an immunocompetent and asymptomatic 56-year-old woman. The diagnosis and therapeutic procedures used in treating the patient are discussed as well as the probable iatrogenic origin of the fungal pathology.

Hydatidiform mole resulting from sexual violence

Background. Hydatidiform mole (HM) is characterized by abnormal proliferation of human trophoblast with producers functioning tissues of human chorionic gonadotropin. It can evolve with ovarian cysts tecaluteínicos, hypertension of pregnancy or hyperthyroidism. The incidence of HM is variable and its etiology poorly known, associated with nutritional factors, environmental, age, parity, history of HM, oral contraceptives, smoking, consanguinity or defects in germ cells. There is no reference in literature on HM resulting from sexual violence, objective of this report. Method. Description of two cases of HM among 1146 patients with pregnancy resulting from sexual violence treated at Hospital Pérola Byington, São Paulo, from July 1994 to August 2011. Results. The cases affected young, white, unmarried, low educated and low parity women. Sexual violence was perpetrated by known offenders unrelated to the victims, under death threat. Ultrasound and CT of the pelvis showed bulky uterus compatible with HM without myometrial invasion. One case was associated with theca lutein cysts. The two cases were diagnosed in the second trimester of pregnancy and evolved with hyperthyroidism. There was no hypertension, disease recurrence, metastasis or sexually transmitted infection. Conclusion. The incidence of HM was 1:573 pregnancies resulting from rape, within the range estimated for Latin American countries. Trophoblastic material can be preserved to identify the violence perpetrator, considering only the paternal HM chromosomes. History of sexual violence should be investigated in cases of HM in the first half of adolescence and women in a vulnerable condition. © 2012 Drezzet et al; licensee BioMed Central Ltd.

Ameloblastoma mandibular rostral em um cão

Odontogenics tumors are uncommon in the dog. Ameloblastoma is considered a benign, aggressive and non-inductive odontogenic neoplasia commonly located in the incisor teeth. Its conclusive diagnosis is obtained by histopathological examination. Due to the expansive nature of this neoplasia, its resection needs to have an adequate surgical margin so it will have excellent prognostics. A canine, male, Pekingese, 8 years old had an increased volume in the rostral region of the mandible, adhered, consistency moderately firm. Radiography revealed extensive mandibular bone lysis caused by the neoplasia. Biopsy identified the tumor as ameloblastoma. Combining data from the clinical, radiographic and histopatological study and after explain to the owner regarding the postoperative esthetic it was held a bilateral rostral mandibulectomy. The fragment removed was assessed radiographically and histopathologically for evidence of tumor at its edges. The patient is active and healthy without evidence of metastasis or recurrence. The radiographic and histopathologic evaluation of edges of the fragment showed no tumor evidence. The patient is active and healthy without evidence of metastasis or recurrence since January 2010 when mandibulectomy was performed.

Interaction between Linepithema micans (Hymenoptera: Formicidae) and Eurhizococcus brasiliensis (Hemiptera: Margarodidae) in vineyards

Eurhizococcus brasiliensis (Wille) (Hemiptera: Margarodidae) is a soil scale that is considered the main pest of vineyards in Brazil. The ant Linepithema micans (Forel) (Hymenoptera: Formicidae) is frequently found associated with this species of scale in infested areas. The effect of the presence of L. micans on the infestation and dispersal capacity of E. brasiliensis on vine roots was measured in a greenhouse, using Paulsen 1103 rootstock seedlings planted in simple and double Gallotti Cages. Treatments measured were: infestation of roots with E. brasiliensis or L. micans, and infestation with both species together. In the experiment using simple Gallotti Cages, with E. brasiliensis associated with L. micans, higher mean numbers of cysts and ants per plant were recorded, a result significantly different from that found for infestation with scale only. When double Gallotti Cages were used, first-instar nymphs were transported between the cages. The results showed that L. micans transports and aids in the attachment of E. brasiliensis to vine plants. © 2013 Entomological Society of America.

Tissue engineering: Using collagen type i matrix for bone healing of bone defects

Among the many tissues in the human body, bone has been considered as a powerful marker for regeneration and its formation serves as a prototype model for tissue engineering based on morphogenesis. Therefore, collagen type I is one of the most useful biomaterials used in tissue engineering as extracellular matrix components capable to promote bone healing. The literature reveals excellent biocompatibility and safety due to its biological characteristics, such as biodegradability and weak antigenicity, making collagen type I the primary resource in medical applications. Thus, it was also used for tissue engineering including skin replacement, bone substitutes, and artificial blood vessels and valves. The authors describe the treatment of an abscessed apical periodontal cyst and show good outcomes of bone healing, using tissue engineering, as collagen type I matrix. © 2013 by Mutaz B. Habal, MD.

Enfisema lobar congênito: série de casos de 30 anos em dois hospitais universitários

Objetivo: Revisar os casos de enfisema lobar congênito (ELC) operados nos últimos 30 anos em dois hospitais universitários. Métodos: Foram revistos os prontuários médicos das crianças com ELC operadas no Hospital das Clínicas da Faculdade de Medicina de Botucatu e no Hospital da Universidade de Mogi das Cruzes entre 1979 e 2009. Dados sobre sintomas, exame físico, achados radiológicos, diagnóstico, tratamento cirúrgico e seguimento pós-operatório mediato e tardio foram analisados. Resultados: Durante o período estudado, 20 crianças com ELC foram submetidas a tratamento cirúrgico. A média de idade dos pacientes no momento da cirurgia foi 6,9 meses (variação, 9 dias a 4 anos). Todos os casos apresentaram sintomas ao nascimento ou nos primeiros meses de vida. Em todos os casos, a radiografia simples de tórax foi importante na definição do diagnóstico. Em casos de dificuldade respiratória moderada, a TC de tórax auxiliou no diagnóstico. Um paciente com desconforto respiratório grave foi diagnosticado erroneamente com pneumotórax hipertensivo e submetido a drenagem torácica. A broncoscopia só foi realizada nos pacientes com dificuldade respiratória moderada e não foram encontrados sinais de anomalias traqueobrônquicas. A abordagem cirúrgica foi realizada através de toracotomia lateral poupadora de músculo. O lobo superior esquerdo e o lobo médio foram os mais afetados, seguidos pelo lobo superior direito. A lobectomia foi realizada em 18 casos, enquanto a bilobectomia foi realizada em 2 casos (com ressecção de cisto broncogênico em 1 desses). Complicações pós-operatórias não foram observadas. O acompanhamento pós-operatório foi de pelo menos 24 meses (média, 60 meses) e não foram observadas complicações tardias nesta série. Conclusões: O ELC é uma doença pouco comum, ainda negligenciada, de etiologia incerta, mas de fácil diagnóstico radiológico e tratamento cirúrgico eficaz.

Five-year follow-up of modified implant-supported overdenture in an iliac crest autograft failure: Clinical report

The treatment of extensive pathologic lesions in the jaw, most of the time, can generate rehabilitation problems to the patient. The solid ameloblastoma is a locally invasive odontogenic tumor with a high recurrence rate. Its treatment is aggressive and accomplished through resection with safety margin. The criterion standard for reconstruction is autogenous bone, but it can provide a high degree of resorption, causing inconvenience to the patient because of lack of rehabilitative option. This study aimed to describe a patient with ameloblastoma treated through resection and reconstruction with autogenous bone graft, in which, after an extensive resorption of the graft was made, a modified bar was applied to support a prosthetic implant overdenture. Copyright © 2013 by Mutaz B. Habal, MD.

Terapêutica medicamentosa em odontologia: antibióticos

Pós-graduação em Odontologia - FOA