Evaluation of remote teaching in master programs in the Oral Pathology and Oral Medicine during the COVID-19 pandemic. Brazilian multicentric study.

BACKGROUND: With the COVID-19 pandemic, there was a need to adopt online teaching methods in a generalized and sudden way, a situation that led to unprecedented changes in the routine of post-graduate students and research development. This study aimed to analyze the evaluation of remote teaching by graduates of master's degrees and advisors in master's programs in the Oral Pathology and Oral Medicine who needed to adapt to a remote teaching methodology in the pandemic. MATERIAL AND METHODS: This quantitative study evaluated the remote teaching in the perception of master's graduates and advisors from postgraduate programs in Oral Pathology and Oral Medicine. Data were collected through an online Google forms® questionnaire. RESULTS: Participated in the study 14 master graduates and 14 master's advisors. Master graduates evaluated that the professors had a good performance (p=0.001), that the duration of the classes was adequate (p=0.015), that the interaction with professors was satisfactory (p=0.007), that they had good interaction with the advisor (p=0.001), that they were satisfied with the remote guidance process (p=0.038) and that face-to-face practical activities were missed (p=0.002). Master's advisors reported satisfaction with remote teaching, good adaptation (p=0.018) and motivation for remote teaching (p=0.016), they evaluated that students were cooperative in activities (p=0.019) and that face-to-face practical activities were missed (p=0.002). CONCLUSIONS: Despite the difficulties, remote teaching proved to be an effective alternative to face-to-face teaching.

Association between DNA ploidy and micronucleus frequency in chronic smokers and impact of smoking cessation.

Tobacco use may initiate the process of oral carcinogenesis with clinically undetectable changes. Smoking cessation may prevent its progression. The objective of this study was to evaluate the association between DNA ploidy and micronucleus (MN) frequency in chronic smokers. Three groups were evaluated: Smoker Group, Former Smoker Group and Control Group. Exfoliative cytology was performed on the lateral border of the tongue and mouth floor. MN and DNA ploidy analyses were performed, as well as the correlation between the variables. The data showed a difference between the groups for the total MN (p = 0.0227), and the Smoker group had the highest mean (4.22 ± 4.12). The three groups did not differ statistically from each other on ploidy evaluation (p-value > 0.05). There was also an association between aneuploidy and increased MN frequency in the Former Smoker group (p = 0.0036). In conclusion, these results point out that there is a relationship between the frequency of MN and aneuploidy in former smokers. Moreover, smoking cessation, even for a short period of time, may promote the decrease of MN frequency caused by tobacco use.

Persistent dysgeusia post-halitosis treatment: How does it impact the patients' quality of life?

BACKGROUND: The objective of this study was to evaluate the quality of life and the presence of anxiety and depression in patients with dysgeusia post halitosis treatment. MATERIAL AND METHODS: Sixty patients were divided into three groups: Dysgeusia group (DG); Halitosis group (HG) and Control group (CG). The following instruments were used: Medical results study Short form health research of 36 items (SF-36), State-state anxiety inventory (STAI) and Self-report questionnaire-20 (SRQ-20). RESULTS: Of the 60 subjects studied, 85% were female and 15% were male. The evaluation of SF-36 indicated a statistically significant correlation between some domains for DG and showed low scores for Mental Health. In relation to HG, low scores were obtained for Bodily Pain, Vitality and Emotional Role. The CG showed low scores for Bodily Pain, General Health and Vitality. STAI was significant when DG was compared to HG and CG. The mean SRQ-20 score was higher in DG compared with the other groups. CONCLUSIONS: Persistent dysgeusia post-halitosis treatment impacts on QoL generically in the Mental health domain, and specifically in trait and state anxiety. Symptoms of depression were also seen in this group of patients.

Responses of the weed Bidens pilosa L. to exogenous application of the steroidal saponin protodioscin and plant growth regulators 24-epibrassinolide, indol-3-acetic acid and abscisic acid.

The exogenous application of plant hormones and their analogues has been exploited to improve crop performance in the field. Protodioscin is a saponin whose steroidal moiety has some similarities to plant steroidal hormones, brassinosteroids. To test the possibility that protodioscin acts as an agonist or antagonist of brassinosteroids or other plant growth regulators, we compared responses of the weed species Bidens pilosa L. to treatment with protodioscin, brassinosteroids, auxins (IAA) and abscisic acid (ABA). Seeds were germinated and grown in agar containing protodioscin, dioscin, brassinolides, IAA and ABA. Root apex respiratory activity was measured with an oxygen electrode. Malondialdehyde (MDA) and antioxidant enzymes activities were assessed. Protodioscin at 48-240 µm inhibited growth of B. pilosa seedlings. The steroidal hormone 24-epibrassinolide (0.1-5 µm) also inhibited growth of primary roots, but brassicasterol was inactive. IAA at higher concentrations (0.5-10.0 µm) strongly inhibited primary root length and fresh weight of stems. ABA inhibited all parameters of seedling growth and also seed germination. Respiratory activity of primary roots (KCN-sensitive and KCN-insensitive) was activated by protodioscin. IAA and ABA reduced KCN-insensitive respiration. The content of MDA in primary roots increased only after protodioscin treatment. All assayed compounds increased APx and POD activity, with 24-epibrassinolide being most active. The activity of CAT was stimulated by protodioscin and 24-epibrassinolide. The results revealed that protodioscin was toxic to B. pilosa through a mechanism not related to plant growth regulator signalling. Protodioscin caused a disturbance in mitochondrial respiratory activity, which could be related to overproduction of ROS and consequent cell membrane damage.

Expression of ATP6V1C1 during oral carcinogenesis.

We investigated the gene and protein expressions of V-type ATPase protein subunit C1 (ATP6V1C1) in cases of oral squamous cell carcinoma (OSCC) and contralateral normal mucosa in smokers, nonsmokers and former smokers. Subjects were separated into five groups of 15: group 1, smokers with OSCC; group 2, normal contralateral mucosa of OSCC patients; group 3, chronic smokers; group 4, former smokers who had stopped smoking 1 year earlier; group 5, individuals who had never smoked. Exfoliative cytology specimens from oral mucosa of smokers, former smokers and nonsmokers showed normal gene and protein expression. We found significantly greater gene expression in the OSCC group than in the nonsmoker groups. No difference in gene expression was observed between normal contralateral mucosa and nonsmoker groups, smoker and nonsmoker groups or former smoker and nonsmoker groups. We observed intense immunostaining for ATP6V1C1 protein in all cases of OSCC and weak or no staining in smoker, former smoker and nonsmoker groups. Significantly greater expression of ATP6V1C1 protein was observed in the OSCC group compared to the other groups, which supports the role of ATP6V1C1 in effecting changes associated with oral cancer. Analysis of the mucosae of chronic smokers, former smokers and the normal contralateral mucosa of patients with OSCC showed unaltered ATP6V1C1 gene and protein expression. Early stages of carcinogenesis, represented by altered epithelium of chronic smokers, had neither gene nor protein alterations as seen in OSCC. Therefore, we infer that the changes in ATP6V1C1 occur during later stages of carcinogenesis. Our preliminary study provides a basis for future studies of using ATP6V1C1 levels for detecting early stage OSCC.

Keratocyst of the buccal mucosa: case report and immunohistochemical comparative study with sporadic intraosseous keratocystic odontogenic tumor.

OBJECTIVES: Describe a new case of keratocyst of the buccal mucosa and compare its immunohistochemical features with 13 sporadic intraosseous keratocystic odontogenic tumors (KOT). CASE REPORT AND STUDY DESIGN: A male complaining about an enlargement on the left buccal mucosa was referred to the Stomatology Clinic. Clinical examination revealed a solitary nodule posterior to the parotid papilla. An excisional biopsy was performed following clinical diagnosis of epidermoid cyst. Microscopically, the lesion was characterized by a lining of five cell layers, with columnar basal cells and a corrugated parakeratinized surface. Immunohistochemical reactions for PTCH-1, Smo, Shh, mTOR, bcl-2, Ck17, and Ck19 were performed. PTCH-1 was not expressed in the keratocyst of the buccal mucosa, but was observed in suprabasal layers of eight (61.5%) cases of sporadic intraosseous KOT. Shh, mTOR, bcl-2, Ck17, and Ck19 expression was observed in all the cases investigated. CONCLUSIONS: The morphology and immunoprofile of this lesion are similar to sporadic intraosseous KOT.

Calcitonin in bone-guided regeneration of mandibles in ovariectomized rats: densitometric, histologic and histomorphometric analysis.

The aim of the present study was to investigate bone promotion in surgical defects created in the mandible of normal and ovariectomized female rats using calcitonin associated with a polytetrafluoroethylene barrier. The 100 female rats were divided into four groups: control (C), control treated with calcitonin (CM), ovariectomized control (OV) and ovariectomized treated with calcitonin (OVM). A circumscribed bone defect 4mm in diameter was created in the region of the mandibular angle, and covered with the barrier. Groups CM and OVM received 2 IU/kg of synthetic salmon calcitonin intramuscularly three times a week. The animals were killed 3, 7, 14, 21 and 28 days after surgery. The bone defects were submitted to densitometric, histologic and histomorphometric analysis. Groups C and CM showed higher levels of bone formation after 7 days compared to the OV and OVM groups. A significant difference was observed between groups C and OV at 3-14 days. The OV group presented slower bone regeneration of the surgical bone defect created in the mandibular angle than group C. Synthetic salmon calcitonin accelerated regeneration of the bone defect in the mandibles of OVM animals similarly to group C, and also increased the formation of new bone during the regeneration process in CM.

Effect of calcitonin on bone regeneration in male rats: a histomorphometric analysis.

The aim of this study was to evaluate the effectiveness of calcitonin in promoting bone growth in surgical bone defects in rat mandibles. Fifty male rats were divided into two groups: bone defect (control) and bone defect with calcitonin (experimental). A circular bone defect 4mm in diameter was made in the mandibular bone of the rats in the angle region, and covered with a polytetrafluoroethylene barrier. The experimental group received 2 IU/kg of synthetic salmon calcitonin intramuscularly three times a week, with treatment starting immediately after surgery. The animals were killed 3, 7, 14, 21 and 28 days after the surgical procedure. The bone defects were examined histologically and by histomorphometric analysis. The Student t-test was applied to the histomorphometric data, with the level of significance set at 5%. The animals of the experimental group showed a lower level of bone formation at almost all time points than the control group, but no difference between groups was observed 28 days after surgery. The volume of newly formed bone matrix was significantly greater in the control than the experimental group at 7, 14 and 21 days, as determined by both morphologic and histomorphometric analysis. Bone repair in the calcitonin-treated animals was delayed in comparison to controls, indicating the need for further studies on male rats.

Hand, foot, and mouth disease: a case report.

Hand, foot, and mouth disease is a viral infection related to coxsackieviruses A5, A6, A9, and A10, coxsackieviruses B2 and B5, and echovirus 11. It generally affects children, but this article presents a clinical case of a young woman with hand, foot, and mouth disease. Patients with this disease have oral and skin lesions that may be confused with other diseases. The differential diagnosis is very important because both dental and medical professionals may misdiagnose the disease and sometimes prescribe an inappropriate medication.

Supernumerary mesiodentes with familial character: a clinical report.

This article reports the occurrence of mesiodentes in three siblings. The etiology of this condition is discussed and genetic considerations, such as modes of inheritance and prevalence, are discussed.

[Coronary angioplasty using double balloon in artery of large calibre (hugging balloons)]. / Angioplastia coronária com uso de duplo balão em artéria de grande calibre (hugging balloons).

In this case report the transluminal coronary angioplasty was performed in a oversized right coronary artery with a severe lesion with thrombus inside, using the Hugging balloon technique (two dilatation balloon catheters used simultaneously). This technique achieved minimal residual lesion and had a favorable clinical outcome of the patient.

Electron microscopic detection of human parvovirus (B19) in a patient with HIV infection.

We report the findings on an HIV-positive patient found to be infected with human parvovirus B19. In a comparative study of sequential sera, direct electron microscopy (EM) had the same sensitivity as DNA hydridization for the detection of the virus. EM did not require specific reagents and also yielded information on the state of the virus; i.e., whether random or complexed, and the type of antibody involved. The presence of parvovirus complicated the judgement as to drug treatment. This case also highlighted the importance of diagnosing the presence of opportunistic viral infections that have no, or low-grade, pathogenic activity.

Recovery of antigenically reactive HIV-2 cores.

Negative staining studies of human immunodeficiency virus (HIV) have been hampered by the fragile nature of the particles. Although detergent treatment is capable of releasing cores from HIV-2 particles, these are unstable and do not retain morphological integrity. Addition of glutaraldehyde will stabilise these structures but, if used at too high a concentration, will destroy their antigenicity. This study shows that if both detergent and glutaraldehyde are used in correct proportions, antigenically reactive cores can be recovered from HIV-2 cell cultures. More specifically we show that a mixture of 0.1% Nonidet P40 and 0.1% glutaraldehyde produces preparations of HIV-2 cores that are suitable for immune electron microscopy. These cores reacted positively, that is, formed immune complexes, with both human HIV-2 antisera and a mouse monoclonal antibody that, although directed against p24 (HIV-1), reacts also with p25 (HIV-2).

Further studies of HIV morphology by negative staining.

Thin-section studies of HIV-1- and HIV-2-infected cells were used to establish peak virus productivity and distribution of virus on and around infected cells. Maximum virus yields occurred 7 days after passage; cells at that stage were used as a source of virus for negative staining. Various methods of separating virus and cells were assessed: results showed that gentle homogenization in a Tenbroek-type homogenizer yielded considerably more virus than other techniques. Virus obtained in this way mainly appeared in the form of large clumps. Because of the large numbers of virus particles obtained it was possible to visualize what is probably the immature form of the virus. The inner component of this particle is spherical and, as is discussed, is a transient form proceeding to the now well established, mature, cone-shaped virus core.

The morphology of human immunodeficiency virus (HIV) by negative staining.

We have examined preparations of human immunodeficiency virus 1 (HIV-1) and HIV-2 by negative staining electron microscopy. HIV-2 cultures contained large numbers of 130-200 nm particles containing a 130-nm-long by 30-70 nm-wide core. This core is probably of conical or pear-shaped morphology. Some particles exhibited a short fringe that could be seen to comprise a regular arrangement of repeating subunits when visualised end on. Identical particles were found in HIV-1 cultures but in much lower numbers. Attempts to carry out negative staining immune EM were unsuccessful. Also detected in both HIV-1 and HIV-2 cultures were small (70-80 nm) fringed viruslike particles. The possible significance of these particles is discussed.

Rapid diagnosis and management of parainfluenza I virus infection in common marmosets (Callithrix jacchus).

During 1983 a severe episode of respiratory infection occurred in a marmoset colony at these laboratories. Of 91 marmosets, 69 showed clinical signs of disease, one died and nine were so ill that euthanasia was necessary. Eight were examined post mortem and all showed consolidation of the lungs. Laboratory studies were carried out in an attempt to establish the cause of the outbreak and an interstitial pneumonia was found in seven animals which were examined histologically. Direct electron microscopy of nasal swabs and lung samples revealed the presence of a high titre of a paramyxovirus, and subsequent immunofluorescence studies established that the particular paramyxovirus involved was parainfluenza virus type I. Subsequent studies showed that surviving affected animals had seroconverted to parainfluenza I virus while animals that had not been implicated in the outbreak had not.

A regular subunit pattern seen on non-infectious Newcastle disease virus particles.

A pseudo-crystalline array of subunits has been observed on particles of the La Sota, in contrast to the Ulster , strain of Newcastle disease virus (NDV) grown in MDBK tissue culture without trypsin. This regular arrangement of subunits was associated with the semi-permissive nature of the tissue culture system, as it disappeared when trypsin, which allows infectious virus to be made, was added. The phenomenon described was considered to be related to the crystalline array of matrix protein which has been described inside the envelope of Sendai virus and NDV by others.

Monoclonal antibodies to herpes simplex virus type 1 glycoproteins show that epitope location influences virus neutralization.

Three monoclonal antibodies, G8D1 , C2D2 , and TI57 , reacting with herpes simplex virus type 1 glycoproteins have been characterised according to the location of their epitope and ability to neutralize infective virus. Immune electron microscopy and a blocking radioimmunoassay were used to locate the epitopes. The results indicate that the epitope recognised by G8D1 is located on the surface of the glycoprotein fringe, whereas those recognized by C2D2 and TI57 are interior with respect to this. Only G8D1 has neutralizing activity alone, whereas C2D2 can neutralize when antiglobulin is added. Thus, epitope location and density determine the neutralizing capacity of individual antibody molecules.

An electron microscope study of three-component immune complexes.

Immune electron microscopy has been used to examine the appearance of three-component complexes. The three components are antigen, supplied by two dissimilar viruses, antibody, and a secondary immune reactant. Secondary reagents used in the study are antispecies immunoglobulin (anti-IgG), rheumatoid factor (RF), and complement. Each of these secondary reagents produced cross-linking between antigenically unrelated immune complexes, and it was found possible to distinguish visually the mixed complexes produced by each of them. The significance of the appearance of these mixed complexes is discussed and related to the neutralisation enhancement that can occur in the presence of secondary immune reactants. The appearance of the complexes is also related to the false positive results that can be obtained in carrying out solid phase immunoassays.