Ozone gas therapy for tooth bleaching preserves enamel microhardness, roughness and surface micromor

After ozone therapy for bleaching, it is important to evaluate enamel surface properties, to ensure that bleaching provides adequate conditions for sound dental substrate. Aim: The aim of this in vitro study was to evaluate the effects of a bleaching treatment with 10% carbamide peroxide (CP), with or without ozone (O), on the microhardness, roughness and micromorphology of the enamel surface. Materials and Method: Bovine enamel blocks were planed and distributed among the following three bleaching treatment groups (n=10): CP - 1 hour per day/14 days (Opalescence PF 10%/ Ultradent); O - 1 hour per day every 3 days/3 sessions (Medplus V Philozon, 60 mcg/mL and oxygen flow rate of 1 L/min); and OCP - CP with O, 1 hour per day every 3 days/3 sessions. Enamel surface microhardness (Knoop), roughness (Ra), and micromorphology by scanning electron microscopy (5,000x magnification) were determined before and after the treatments. Results: ANOVA and Tukey-Kramer’s test showed that enamel microhardness remained unchanged by treatment with O and OCP (p=0.0087), but decreased by treatment with CP. Treatment with O promoted higher enamel microhardness than the other groups (p=0.0169). Generalized linear mixed models for repeated measures over time indicated treatment with CP increased enamel roughness more than OCP or O (p=0.0003). CP produced slight irregularities in enamel micromorphology after the whitening treatment. O, with or without CP, maintained the mechanical and physical properties of microhardness and enamel surface micromorphology, and either maintained or reduced surface roughness, compared to the conventional tray-delivered CP bleaching treatment. Conclusions: Treatment with 10% carbamide peroxide in trays promoted greater changes in enamel surface properties than treatments with ozone and with 10% ozonized carbamide peroxide in the office.

Long-Term Consequences of High Polychlorinated Biphenyl Exposure: Projected Decline of Delphinid Populations in a Hotspot for Chemical Pollution

Rough-toothed dolphins, Steno bredanensis, are closely associated with coastal waters in the Southwestern Atlantic Ocean, increasing the exposure to multiple stressors, such as chemical pollution. Persistent organic pollutants (POPs) are known to affect the health of cetacean species. To comprehend the potential impacts of POPs on populations' viability, it is necessary to distinguish populations and predict their risk of long-term exposure. Blubbers of rough-toothed dolphins (n = 28) collected along the southeastern (SE) and southern (S) Brazilian coast were screened for polychlorinated biphenyls (PCBs) and pesticides in a gas chromatograph coupled to a mass spectrometer. Based on the contamination profile, a discriminant function analysis separated the rough-toothed dolphins into three ecological populations: two coastal and one offshore. POP concentrations were the highest reported for the species worldwide and highest among the delphinids in Brazilian waters, reaching 647.9 μg g^-1 lw for PCBs. The SE population presented 212.9 ± 163.0, S population presented 101.0 ± 96.7, and OCS/S population presented 183.3 ± 85.3 μg g^-1 lw (mean ± SD) of PCBs. The potential risk of effects triggered by elevated PCB concentrations was assessed in an individual-based model. A risk of severe decline in population size is projected for the three populations in the next 100 years, especially in SE Brazil, varying between 67 and 99%.

The use of non-surgical glue to repair perineal first-degree lacerations in normal birth: A non-inferiority randomised trial

BACKGROUND AND PROBLEM

Surgical glue has been indicated for uncomplicated operatory wounds; however, it has a considerable cost. Non-surgical glue, a commercially available and cheaper product, has not been studied for repairing postpartum lacerations.

AIM

To compare non-surgical glue to traditional sutures on perineal first-degree lacerations after normal birth.

METHODS

In a prospective, open-label, non-inferiority, randomised controlled trial, we selected childbearing women who were admitted for normal term births and in whom skin lacerations occurred. They were assigned to laceration repair using either non-surgical glue (ethyl 2-cyanoacrylate; Glue group) or catgut sutures (Suture group). The primary endpoint was the occurrence of dehiscence >3mm. Secondary endpoints were procedure runtime, pain score, satisfaction level, and aspects of perineal repair by the REEDA score (hyperaemia, oedema, ecchymosis, exudation, and coaptation) immediately (T0), 24-48h (T1), and 7-10 days (T2) after childbirth.

FINDINGS

We included 126 women, 63 in each group, and found a non-inferiority dehiscence rate in the Glue Group compared to the Control group (T1=1.6% vs. 1.6%, P=0.999 and P<0.001 for non-inferiority; and T2=2.2% vs. 4.3%, P=0.557). In the Glue Group, the procedure runtime was shorter, pain score was lower, and women's satisfaction was greater. No women had any allergic reaction in the study.

CONCLUSIONS

Non-surgical glue was not inferior to traditional sutures to repair postpartum first-degree lacerations. In addition, non-surgical glue was associated with less pain and greater satisfaction. Brazilian Clinical Trials Registry (www.ensaiosclinicos.gov.br/rg/RBR-5Z8MKC).

The Pathology of Cetacean Morbillivirus Infection and Comorbidities in Guiana Dolphins During an Unusual Mortality Event (Brazil, 2017-2018)

Cetacean morbillivirus (CeMV; Paramyxoviridae) is the most significant pathogen of cetaceans worldwide. The novel "multi-host" Guiana dolphin (Sotalia guianensis; GD)-CeMV strain is reported in South American waters and infects Guiana dolphins and southern right whales (Eubalaena australis). This study aimed to describe the pathologic findings, GD-CeMV viral antigen distribution and detection by RT-PCR (reverse transcriptase polymerase chain reaction), and infectious comorbidities in 29 Guiana dolphins that succumbed during an unusual mass-mortality event in Rio de Janeiro state, Brazil, between November 2017 and March 2018. The main gross findings were lack of ingesta, pulmonary edema, ascites, icterus, hepatic lipidosis, multicentric lymphadenomegaly, as well as pneumonia, polyserositis, and multiorgan vasculitis caused by Halocercus brasiliensis. Microscopically, the primary lesions were bronchointerstitial pneumonia and multicentric lymphoid depletion. The severity and extent of the lesions paralleled the distribution and intensity of morbilliviral antigen. For the first time in cetaceans, morbilliviral antigen was detected in salivary gland, optic nerve, heart, diaphragm, parietal and visceral epithelium of glomeruli, vulva, and thyroid gland. Viral antigen within circulating leukocytes suggested this as a mechanism of dissemination within the host. Comorbidities included disseminated toxoplasmosis, mycosis, ciliated protozoosis, and bacterial disease including brucellosis. These results provide strong evidence for GD-CeMV as the main cause of this unusual mass-mortality event.

Guiana Dolphin Unusual Mortality Event and Link to Cetacean Morbillivirus, Brazil

During November-December 2017, a mass die-off of Guiana dolphins (Sotalia guianensis) began in Rio de Janeiro, Brazil. Molecular and pathologic investigations on 20 animals indicated that cetacean morbillivirus played a major role. Our findings increase the knowledge on health and disease aspects of this endangered species.

Cetacean movements in coastal waters of the southwestern Atlantic ocean

Abstract: Cetaceans were monitored along ca. 700 km of the southeast coast of Brazil (22°S to 25°S) from 1995 to 2014 using photo-identification. The objective of this study was to identify any presence of long-distance movements for monitored cetacean species and discuss implications. Data on long-range movements of four of the monitored species are presented after the analysis of 321,765 photographs taken for individual identification. Seven individuals from four populations of Guiana dolphins (Sotalia guianensis) considered resident to particular estuaries or bays were reported in dispersal involving movement between pairs of protected areas over long-range distances varying between 86 and 135 km. Three cataloged rough-toothed dolphins (Steno bredanensis), first seen in Guanabara Bay, Rio de Janeiro state (22°46'S) in November 2011, were sighted 240 km southwards as members of the same group in coastal waters of São Paulo state (23°46'S) in July 2014. Water depth for those sightings ranged from 16 to 52.7 m; local sightings of rough-toothed dolphins in Brazil have frequently been in shallow waters, but the species global distribution is usually associated with deeper waters. In a 27-day interval in the spring of 2012, a group of 16 orcas (Orcinus orca) travelled ca. 277 km in shallow coastal waters ranging from 20 to 30 m deep. Orcas are commonly observed between November and February in southeast Brazil, probably in search for prey. In summer months between 2012 and 2014, three Bryde's whales (Balaenoptera edeni) sighted in waters ranging from 14 to 49 m deep, moved between 218 and 327 km. Bryde's whales are usually found in local coastal waters where they spend summer months feeding on sardines. To date, these are the longest estimated movements reported to S. guianensis, S. bredanensis, O. orca and B. edeni in the Southwestern Atlantic Ocean.

Underwater noise in an impacted environment can affect Guiana dolphin communication

This study focused on whistles produced by Guiana dolphin under different noise conditions in Guanabara Bay, southeastern Brazil. Recording sessions were performed with a fully calibrated recording system. Whistles and underwater noise levels registered during two behavioral states were compared separately between two areas. Noise levels differed between the two areas across all frequencies. Whistle duration differed between areas and was negatively correlated with noise levels. Whistling rate was positively correlated with noise levels, showing that whistling rate was higher in noisier conditions. Results demonstrated that underwater noise influenced Guiana dolphin acoustic behavior.

Underwater noise pollution in a coastal tropical environment

Underwater noise pollution has become a major concern in marine habitats. Guanabara Bay, southeastern Brazil, is an impacted area of economic importance with constant vessel traffic. One hundred acoustic recording sessions took place over ten locations. Sound sources operating within 1 km radius of each location were quantified during recordings. The highest mean sound pressure level near the surface was 111.56±9.0 dB re 1 μPa at the frequency band of 187 Hz. Above 15 kHz, the highest mean sound pressure level was 76.21±8.3 dB re 1 μPa at the frequency 15.89 kHz. Noise levels correlated with number of operating vessels and vessel traffic composition influenced noise profiles. Shipping locations had the highest noise levels, while small vessels locations had the lowest noise levels. Guanabara Bay showed noise pollution similar to that of other impacted coastal regions, which is related to shipping and vessel traffic.

Candida albicans and non-C. albicans Candida species: comparison of biofilm production and metabolic activity in biofilms, and putative virulence properties of isolates from hospital environments and infections

Candida albicans and, more recently, non-C. albicans Candida spp. are considered the most frequent fungi in hospitals. This study analyzed Candida spp. isolates and compared the frequency of different species, that is, C. albicans and non-C. albicans Candida spp., and the origins of isolates, that is, from hospital environments or infections. Yeast virulence factors were evaluated based on biofilm production and metabolic activity. Hemolysin production and the antifungal susceptibility profiles of isolates were also evaluated. Candida spp. were highly prevalent in samples collected from hospital environments, which may provide a reservoir for continuous infections with these yeasts. There were no differences in the biofilm productivity levels and metabolic activities of the environmental and clinical isolates, although the metabolic activities of non-C. albicans Candida spp. biofilms were greater than those of the C. albicans biofilms (p < 0.05). Clinical samples had higher hemolysin production (p < 0.05) and lower susceptibility to fluconazole (p < 0.05). Non-C. albicans Candida spp. predominated in samples collected from hospital environments and infections (p < 0.05). These species had a lower susceptibility to fluconazole and amphotericin B, and their biofilms had higher metabolic activities than those produced by C. albicans, which may explain the increased incidence of fungal infections with these yeasts during recent years.

Study on the embryofeto-toxicity of citral in the rat

Citral, 3,7-dimethyl-2,6-octadien-1-al, found in the essential oils of a large variety of useful plants, is used as a scenting agent in household products, as a fragrance in cosmetics, and as a food flavouring additive. This study was undertaken to investigate the embryofeto-toxic potential of citral in the rat. Citral (60; 125; 250; 500 and 1000 mg/kg) in corn oil was given orally to Wistar rats from day 6 to 15 of pregnancy. Caesarean sections were carried out on day 21 of pregnancy, and the number of resorptions and implantation sites were recorded. Fetuses were weighed, examined for external malformations, and fixed for visceral examination, or cleared and stained with Alizarin Red S for skeleton evaluation. A transient decrease in weight gain from days 6 to 11 of gestation at the lowest doses, and a reduction in body weight minus uterine weight at term at the highest doses, indicated that citral was maternally toxic over the dose range tested. A slight but statistically significant increase in the ratio of resorptions per implantations was observed with 60 and 125 mg/kg body weight. Doses higher than 125 mg/kg reduced dose-dependently the ratio of pregnant per mated female. Signs of fetal growth retardation and a higher incidence of minor skeletal abnormalities were found in doses higher than 60 mg/kg. No increase in the frequency of visceral anomalies was found at any dose level, but an increase in fetal spleen weight was observed in doses higher than 125 mg/kg. Therefore, data presented in this paper indicate that the no-observed adverse effect level for embryofeto-toxicity is lower than 60 mg citral/kg body weight p.o.

Study on embryo-foetotoxicity of beta-myrcene in the rat

beta-Myrcene is a constituent of many essential oils that have been used extensively in cosmetic fragrances and as flavouring additives in the food industry. Recently, this monoterpene was reported to be an analgesic substance. Notwithstanding the widespread use of myrcene and essential oils containing myrcene in perfume and in food additives, experimental studies on the toxicity of this substance are still scarce. This study aimed to provide data on the embryo-foetotoxic potential of beta-myrcene in the rat. beta-Myrcene (0.25, 0.5 and 1.2 g/kg) in corn oil was given orally to Wistar rats from day 6 to 15 of pregnancy. Caesarean sections were performed on day 20 of pregnancy, and the number of resorptions and implantation sites were recorded. Foetuses were weighed, examined for external malformations, and fixed for visceral examination, or cleared and stained with Alizarin Red S for skeleton evaluation. No adverse effects were seen with the two lowest doses tested. Decreased weight gain during the first days of treatment and the death of one of 29 treated dams indicated that the highest dose tested (1.2 g/kg) induced maternal toxicity. A higher incidence of signs of retardation and of anomalies in the foetal skeleton indicated that 1.2 g/kg was also toxic to the rat embryo. From the data presented in this paper the no-observed-adverse-effect level for embryo-foetotoxicity could be set at 0.5 g beta-myrcene/kg body weight.

[Precocious puberty caused by intracranial tumors]

São relatados 4 casos de puberdade precoce conseqüentes a tumores intracranianos: um teratoma adulto do ventrículo lateral, um astrocitoma protoplasmático do terceiro ventrículo e diencéfalo, um astroblastoma do ter- ceiro ventrículo e diencéfalo e um hamartoma hipotalâmico. São apresentadas teorias que tentam explicar os mecanismos hormonais envolvidos e é salientada a importância do diagnóstico neuroradiológico preciso, pela possibilidade de cura em alguns casos e de tratamento satisfatório nos demais.

[Hemifacial spasm: results of surgical treatment in 14 cases]

Quatorze pacientes com espasmo hemifacial foram submetidos a exploração cirúrgica e neurolise do 7º par craniano no ângulo ponto-cerebelar. Em 7 pacientes havia indubitável compressão do nervo facial por alça anômala da artéria cerebelar anterior e inferior sendo que um paciente também apresentava malformação de Arnold-Chiari. Em um paciente havia aracnoidite envolvendo o nervo. Em 6 outros, o nervo achava-se aparentemente livre. Houve alívio imediato e duradouro do espasmo em 10 pacientes, 2 permaneceram inalterados e um apresentou recidiva após 10 meses. Houve um óbito no pós-operatório imediato, conseqüente a traumatismo craniano por queda do paciente.

[Post-irradiation cervical myelopathy simulating spinal cord tumor]

Os autores relatam um caso de paciente de 25 anos, masculino, submetido a radioterapia cervical por carcinoma indiferenciado do rinofaringe com metástases ganglionares. Seis meses depois desenvolveu tetraparesia progressiva com exames liquórico e mielográfico compatíveis com diagnóstico de tumor intramedular. O exame histopatológico revelou aspecto característico da mielopatia após irradiação.