Anuran Heart Metamorphosis: Anatomical Support for Pulmonary Blood Separation in the Early Aquatic Phase

Background: In both larval and adult anurans, blood separation and respiratory physiology have remained an enigma. While various blood separation mechanisms have been proposed, the same structure is seen as playing a key role: the conus arteriosus. However, previous findings on its internal structure are contradictory, depending on the specifics of the 2D imaging methods used by different authors. To resolve this problem, we used high-resolution X-ray microtomography of whole Bufo bufo specimens to acquire the first detailed 3D descriptions of this complex structure through metamorphosis. Results: In early tadpoles two small valvular openings develop at the ventricular-conal junction, providing two paths separated by the septum coni and continuing into the aortic arches. Thus, structures to support segregated pulmonary circulation are fully developed well before the lungs appear. The external gills undergo partial resorption and retreat asymmetrically into a gill chamber formed by a hyoidal cover, leaving only a single opening on the left side, the opercular spout. Conclusions: The timing of events in Bufo circulatory development does not track the changing modes of respiration used by the developing tadpole. In particular, a system capable of double circulation carries only oxygen-depleted blood for a significant portion of the tadpole stage.

Use of allogeneic cartilage in reconstruction surgery of laryngeal and tracheal stenosis

This article analyzes the increasing effectiveness of extensive defects and chronic cicatricial laryngeal and tracheal stenosis treatment with the allogeneic cartilage implantation. The study included 63 patients with an age interval of 18–65 years and a disease duration from 3 months to 6 years. Radiologic, functional and endoscopic investigations were carried out, after which the patients underwent laryngotracheoplasty using allogeneic cartilage, which has low antigenicity, affects the growth of the recipient’s tissues and prevents scarring. After the discharge, a dynamic outpatient observation was carried out: 2 times a week – 10 days; once a week – 21 days, once a month - 6 months. The study revealed that a differentiated approach to the treatment of patients with stenosis of the laryngeal-tracheal complex using the allogeneic cartilage made it possible to fully rehabilitate of 59 (94%) of 63 patients (100%). Only 4 (6%) patients had partial resorption or rejection of implanted cartilaginous allografts that led to the failure of the laryngeal and tracheal walls in the late postoperative period. The use of the allogeneic cartilage implantation in reconstructive surgery has proved to be highly effective in the laryngeal and tracheal framework defects, resulted from prolonged stenosis, major surgical interventions, and trauma.

Outcome of Free Diced Cartilage Grafts in Rhinoplasty: A Systematic Review

Diced cartilage grafts are used to increase and refine the nasal contour, providing easy molding and versatility when compared with block grafts. However, all grafts present the possibility of visibility, distortion, and absorption. The aim of this study is to evaluate, through a systematic review, the outcome of the use of the free diced graft cartilage in rhinoplasty. A systematic search of the literature was performed in the databases (PubMed, Lilacs, Scielo, Cochrane) with the terms “diced cartilage” and “rhinoplasty.” Studies were selected according to the inclusion and exclusion criteria and data extracted and grouped for analysis. Six eligible studies were included. In total, 4,044 patients underwent rhinoplasty with free diced cartilage graft, with 61 (1.51%) of them requiring reoperation. The main reasons were overcorrection and irregularities of the nasal dorsum. The infection rate was reported in three studies, with 2 (0.06%) of 3,252 patients presenting infection at the graft site. Two cases of displacement were treated with external molding, without reoperation. The graft resorption was reported in four articles, which described 22 (0.67%) cases of partial resorption in 3,288 patients. Therefore, the available evidence suggests that resorption of the graft and unfavorable outcomes are rare.

Hibrid biomaterials based on hydroxyapatite and blood components

Hybrid biomaterials based on amorphous hydroxyapatite and blood components (fibrin, citrate plasma) were developed by chemical precipitation of hydroxyapatite in a biopolymer matrix (pH 11; Ca/P ratio 1.67) and by mixing 6–14 wt.% of hydroxyapatite gel (pH 7.0–7.2) with bipolymers. Chemically precipitated hydroxyapatite in biopolymer matrices is single phase or contains ticalcium phosphate impurity up to 30 %, mainly α-modification in fibrin matrix and β-modification in citrate plasma. The interaction of hydroxyapatite gel into the fibrin leads to significant amorphization of hydroxyapatite and an increase in its bioresorbability. Holding the composites with hydroxyapatite obtained by chemical precipitation in the Simulated Body Fluid model solution for 75 days leads to their partial resorption and simultaneous increase of biomimetic apatite, with its greater weight gain on composites with a fibrin. Hybrid biomaterials based on a fibrin obtained from the patient’s blood and hydroxyapatite gel showed positive result during implantation, allowing to form an adequate configuration of the defect, expanding the possibilities of ENT surgery.

Teratogenic potential of Urtica massaica (Mildbr.) and Croton megalocarpus (Hutch) in mice

Urtica massaica (Urticaceae) and Croton megalocarpus are used either as vegetables or as food additives and as medicine in traditional African societies. However, in spite of the widespread consumption of these plants as folklore remedies and for diet, there is a scarcity of scientific data on their teratogenicity. Hence this study sought to assess the teratogenic effects of these plant extracts in an animal model. The study was conducted using Swiss albino mice. The extracts of these plants were administered orally in mice which were then euthanized. The weights of the gravid uterus and pups, as well as the number of pups, were determined. The pups were examined for gross malformations. The data set was analysed using one-way analysis of variance and Tukey as the post-Anova test. P < 0.05 was the limit of significance. U. massaica and C. megalocarpus caused 40% and 20% fetal partial resorption respectively. The latter also caused microcephaly and polyhydramnios. Hence, U. massaica leaves and C. megalocarpus stem extracts exhibited teratogenic activity and should be used with care during pregnancy

Squamous Cell Carcinoma in Chinese Hamsters (Cricetulus griseus)

Background: The companion animal market has changed over the years. The number of people living in small apartments has increased; as a result, the demand for small pets such as exotics, fish, and small rodents has also increased due to their smaller space requirements and ease of handling and care. Pets help relieve anxiety and stress in people suffering from social issues. Small rodents are usually bred in specific cages with cellulose or wood shaving bedding, and fed with commercially available diets. Small rodent clinics struggle due to the lack of scientific reports on some diseases and therapies. To date, the oncology literature is too limited to develop better diagnosis and treatment methods. Here, we report three cases of squamous cell carcinoma in the mandibular region of Chinese hamsters (Cricetulus griseus).Case: Three adult male hamsters averaging 1.5 years old, from different pet stores, bred under home conditions by different owners in Sergipe, Brazil, were brought to the Dr. Vicente Borelli Hospital at Pio X University for exotic veterinary care. Each animal had been bred alone in a specific breeding cage. Each had a history of apathy, loss of appetite, andrapid deformity of the facial region. Radiographs showed areas of bone involvement and extensive injury, with partial resorption of the left ramus and angle of the mandibular region. Due to the location of the tumor mass, the clinical status, and limitations in systemic treatment, euthanasia was recommended for each animal. After anamnesis, the animals weresubjected to clinical assessment. A firm and well-circumscribed mass was identified on palpation. In case A, it compromised the left mandible from the angle to the body and extended to the maxillary soft tissues and left superior lips. In case B, it extended from the ramus to the symphysis on the left side and to the maxillary region, similar to case A. In case C,it extended on both sides of the mandible symphysis, with no alterations in the maxillary soft tissues. Following clinical examination, each animal underwent laterolateral and dorsoventral radiographic examination; no images were suggestive of pulmonary metastasis. However, an expansive mandibular lesion with partial resorption, suggestive of bone neoplasia,was detected. The animals were dehydrated and in clinical distress, and euthanasia was recommended. Histopathological examination of samples from the tumor sites revealed moderate cellular and nuclear pleomorphism and proliferation of neoplastic keratinocytes, suggestive of squamous cell carcinoma, a malignant tumor of epidermal keratinocytes with a highly invasive and aggressive nature.Discussion: The number of reports in the literature of cancer in small rodent companion animals has lead us to believe that neoplasms in these animals are misdiagnosed and/or that their prevalence is underreported. The literature describes that the tumor incidence in hamsters is 3-40%, and that the incidence is higher in male rodents. This incidence range increases the analysis of cancer in these animals from rare to middle-frequent what do not contribute to the animals’ clinics and to small rodent therapeutics. Differential diagnosis of squamous cell carcinoma and other tumor types should be addressed, especially osteosarcomas. Histopathological examination is essential to clarify the etiopathogenesis.Keywords: rodents, neoplasm, keratinocytes.

Quantitative and qualitative analysis of bone flap resorption in patients undergoing cranioplasty after decompressive craniectomy

OBJECTIVEAutologous bone cranioplasty after decompressive craniectomy entails a notable burden of difficult postoperative complications, such as infection and bone flap resorption (BFR), leading to mechanical failure. The prevalence and significance of asymptomatic BFR is currently unclear. The aim of this study was to radiologically monitor the long-term bone flap survival and bone quality change in patients undergoing autologous cranioplasty.METHODSThe authors identified all 45 patients who underwent autologous cranioplasty at Oulu University Hospital, Finland, between January 2004 and December 2014. Using perioperative and follow-up CT scans, the volumes and radiodensities of the intact bone flap prior to surgery and at follow-up were calculated. Relative changes in bone flap volume and radiodensity were then determined to assess cranioplasty survival. Sufficient CT scans were obtainable from 41 (91.1%) of the 45 patients.RESULTSThe 41 patients were followed up for a median duration of 3.79 years (25th and 75th percentiles = 1.55 and 6.66). Thirty-seven (90.2%) of the 41 patients had some degree of BFR and 13 (31.7%) had a remaining bone flap volume of less than 80%. Patients younger than 30 years of age had a mean decrease of 15.8% in bone flap volume compared with the rest of the cohort. Bone flap volume was not found to decrease linearly with the passing of time, however. The effects of lifestyle factors and comorbidities on BFR were nonsignificant.CONCLUSIONSIn this study BFR was a very common phenomenon, occurring at least to some degree in 90% of the patients. Decreases in bone volume were especially prominent in patients younger than 30 years of age. Because the progression of resorption during follow-up was nonlinear, routine follow-up CT scans appear unnecessary in monitoring the progression of BFR; instead, clinical follow-up with mechanical stability assessment is advised. Partial resorption is most likely a normal physiological phenomenon during the bone revitalization process.

Evaluation of the Biodegradable Plates (PG910/PDO) for Reconstruction of Various Sizes of Orbital Floor Defects in the Blow-Out Fractures

The aim of our study was to evaluate the biodegradable plates (PG910/PDO) for reconstruction of various sizes of the orbital floor defects in the blow-out fractures. We included patients who had an impure blow-out fracture. All patients had a recent trauma and also the surgical intervention was done between 1 and 10 days after trauma. The amount of the orbital floor defect was measured in each case through computed tomography scan. In the surgical intervention, a biodegradable plate was used for the reconstruction of the orbital floor defect along with titanium miniplates used for bone fixation in orbital rim. Due to aesthetic reasons, all patients underwent secondary surgery including removal of titanium miniplates after 18 months. The orbital floor was reevaluated during the removal of the miniplates. The clinical evaluation of remnant defects and biodegradable plates (presence of complete or partial resorption) were documented for each patient. In our study a total of 15 patients (10 males and 5 females) underwent the orbital floor reconstruction using biodegradable miniplates. The size of the orbital floor defects was meanly 3.51 ± 1.29 cm2. Results demonstrated that 4 out of 15 patients had a remnant defect after resorption of the biodegradable plate. In 10 out of 15 patients, the biodegradable plates completely replaced with fibrous tissues after 18 months. Remaining five patients had partial resorption of plates. There was not any relationship between the defect size and the remnant defects ( p > 0.05). A significant relationship was seen between the defect size and the plates’ resorption rate ( p < 0.001). There is a significant relationship between the resorption rate and the remnant defect. The risk to have remnant defects have been increased as the plates had incomplete resorption. The use of biodegradable plates is an appropriate option for reconstruction of the orbital floor defects. The defect size does not have any effect on the stability of the plate. However, incomplete plate resorption increases the risk of remnant defects in the orbital floor. The larger defects lead to slow degradation of biodegradable plates.

Expansile aneurysmal bone cyst in the tubular bones of the hand treated with en bloc excision and autograft reconstruction: a report of 12 cases

Primary aneurysmal bone cysts (ABCs) in the small tubular bones of the hands are rare and optimal treatment is not yet established. Between August 1997 and June 2009, 12 patients with biopsy-proven expansile primary ABCs of the small tubular bones of the hand were treated with en bloc tumor excision and strut autograft reconstruction. The adjacent joint was preserved if feasible, otherwise it was fused. Patients were followed for at least 2 years (mean = 7 years). All grafts were incorporated except for partial resorption in one. There was only one tumor recurrence about 1 year after the operation. Other complications included premature physeal arrest in one case and limitation of adjacent joint motion in three. A relatively low rate of recurrence and other complications indicates that this technique would serve as a good strategy for patients with expansile ABCs in the hand in terms of safety, simplicity and reduced number of re-operations.