Does silver diammine fluoride concentration influence on bonding to carious dentinal lesions in primary teeth?

PURPOSE: This in vitro study evaluated the microshear bond strength (µSBS) of a universal adhesive after silver diammine fluoride (SDF) application at different concentrations on carious dentinal lesions in primary teeth. METHODS: Flat dentin carious-induced surfaces from 40 primary molars were randomly assigned to four experimental groups: without SDF treatment (control), 12% SDF, 30% SDF, or 38% SDF application. After 14 days of storage in artificial saliva at 37 °C, a universal adhesive system (Scotchbond Universal, 3 M ESPE) was applied in the etch-and-rinse mode and resin composite cylinders were built (0.72 mm2). After 24 h of water storage, the µSBS test was performed and the failure mode was determined. Data were analysed using one-way ANOVA and Tukey's post hoc tests (α = 0.05). RESULTS: The application of 38% SDF resulted in higher µSBS mean than control and use of 12% SDF (p = 0.006). No significant differences were observed among control, 12% SDF, and 30% SDF. All specimens tested showed adhesive/mixed failure. CONCLUSION: The use of SDF does not jeopardise the bonding of a universal adhesive applied in the etch-and-rinse mode to carious dentinal lesions in primary teeth, irrespective of the product concentration.

Dengue infection in mice inoculated by the intracerebral route: neuropathological effects and identification of target cells for virus replication.

Dengue is an important arboviral infection, causing a broad range symptom that varies from life-threatening mild illness to severe clinical manifestations. Recent studies reported the impairment of the central nervous system (CNS) after dengue infection, a characteristic previously considered as atypical and underreported. However, little is known about the neuropathology associated to dengue. Since animal models are important tools for helping to understand the dengue pathogenesis, including neurological damages, the aim of this work was to investigate the effects of intracerebral inoculation of a neuroadapted dengue serotype 2 virus (DENV2) in immunocompetent BALB/c mice, mimicking some aspects of the viral encephalitis. Mice presented neurological morbidity after the 7th day post infection. At the same time, histopathological analysis revealed that DENV2 led to damages in the CNS, such as hemorrhage, reactive gliosis, hyperplastic and hypertrophied microglia, astrocyte proliferation, Purkinje neurons retraction and cellular infiltration around vessels in the pia mater and in neuropil. Viral tropism and replication were detected in resident cells of the brain and cerebellum, such as neurons, astrocyte, microglia and oligodendrocytes. Results suggest that this classical mice model might be useful for analyzing the neurotropic effect of DENV with similarities to what occurs in human.

Erosion of the long process of the incus with incomplete ossicular discontinuity in simple chronic otitis media: Should we reconstruct or leave it be?

OBJECTIVE: To determine whether patients with simple chronic otitis media and incomplete ossicular discontinuity should undergo ossicular reconstruction. DESIGN: Prospective, randomised surgical trial comparing no intervention with incus interposition over a 5-year period. SETTING: Tertiary referral hospital. PARTICIPANTS: Seventy-six participants with simple chronic otitis media and erosion of the long process of the incus but apparent good transmission throughout the ossicular chain as tested intra-operatively. Forty-four patients had partial erosion of the incus but still bony contact with the stapes head (Group A-Type I), and 32 had mainly connective tissue binding the incus and stapes (Group B-Type II). Each of these groups was randomised to either leaving the ossicular chain as it was (A1 and B1) or performing an incus interposition (A2 and B2). MAIN OUTCOME MEASURES: Average postoperative air-bone gap and the degree of ABG closure. A postoperative air-bone gap under 20 dB was considered a successful result. RESULTS: In group A, there was no significant difference between no intervention and incus interposition. In group B, patients in the no reconstruction subgroup had a significantly worse hearing result than the incus interposition subgroup (postoperative air-bone gap of 27.5 dB and 31% closure within 20 dB vs 15 dB and 75% closure). CONCLUSIONS: For Type I patients, the postoperative hearing results were similar for the reconstruction and no reconstruction groups. For Type II patients, the results clearly favour reconstruction.

Peripheral effects induced in BALB/c mice infected with DENV by the intracerebral route.

The lack of an immunocompetent animal model for dengue mimicking the disease in humans is a limitation for advances in this field. Inoculation by intracerebral route of neuroadapted dengue strains in mice is normally lethal and provides a straightforward readout parameter for vaccine testing. However, systemic effects of infection and the immune response elicited in this model remain poorly described. In the present work, BALB/c mice infected by the intracerebral route with neuroadapted DENV2 exhibited several evidences of systemic involvement. DENV-inoculated mice presented virus infective particles in the brain followed by viremia, especially in late stages of infection. Infection induced cellular and humoral responses, with presence of activated T cells in spleen and blood, lymphocyte infiltration and tissue damages in brain and liver, and an increase in serum levels of some pro-inflammatory cytokines. Data highlighted an interplay between the central nervous system commitment and peripheral effects under this experimental condition.

Rutin increases critical wavelength of systems containing a single UV filter and with good skin compatibility.

BACKGROUND/PURPOSE: Ultraviolet (UV) radiation is responsible for sunburns, skin cancer, photoaging, and the production of reactive oxygen species (ROS). The awareness on preventing these deleterious effects made the use of anti-UVB formulations an important part of population habits; however, despite the availability of several antioxidants capable of ROS scavenging, the pharmaceutical market lacks products associating UV filters with natural compounds of proven efficacy. Here, we investigated the effect of rutin, a flavonoid with antioxidant activity, associated with UVB filters in dermocosmetic preparations. METHODS: Formulations were assessed through its antioxidant activity, in vitro photoprotective effectiveness, photostability, and in vivo skin tolerance (hydration, transepidermal water loss, and erythema). RESULTS: Samples containing rutin were compatible with the human skin and presented a pronounced antioxidant potential, with scavenging activity values 75% higher than the ones containing only UVB filters. Although rutin could not prevent the sunscreens photodegradation post-irradiation, the bioactive compound significantly increased the formulations critical wavelengths, showing a photoprotective gain, especially in the UVA range. CONCLUSION: In conclusion, the absorption in the UVA range, coupled with ROS scavenging potential, proved the positive effect of rutin applied to anti-UVB formulations, making this bioactive compound a promising candidate for photoprotection improvement.

Cholesterol reduction ameliorates glucose-induced calcium handling and insulin secretion in islets from low-density lipoprotein receptor knockout mice.

AIMS/HYPOTHESIS: Changes in cellular cholesterol level may contribute to beta cell dysfunction. Islets from low density lipoprotein receptor knockout (LDLR(-/-)) mice have higher cholesterol content and secrete less insulin than wild-type (WT) mice. Here, we investigated the association between cholesterol content, insulin secretion and Ca(2+) handling in these islets. METHODS: Isolated islets from both LDLR(-/-) and WT mice were used for measurements of insulin secretion (radioimmunoassay), cholesterol content (fluorimetric assay), cytosolic Ca(2+) level (fura-2AM) and SNARE protein expression (VAMP-2, SNAP-25 and syntaxin-1A). Cholesterol was depleted by incubating the islets with increasing concentrations (0-10mmol/l) of methyl-beta-cyclodextrin (MßCD). RESULTS: The first and second phases of glucose-stimulated insulin secretion (GSIS) were lower in LDLR(-/-) than in WT islets, paralleled by an impairment of Ca(2+) handling in the former. SNAP-25 and VAMP-2, but not syntaxin-1A, were reduced in LDLR(-/-) compared with WT islets. Removal of excess cholesterol from LDLR(-/-) islets normalized glucose- and tolbutamide-induced insulin release. Glucose-stimulated Ca(2+) handling was also normalized in cholesterol-depleted LDLR(-/-) islets. Cholesterol removal from WT islets by 0.1 and 1.0mmol/l MßCD impaired both GSIS and Ca(2+) handling. In addition, at 10mmol/l MßCD WT islet showed a loss of membrane integrity and higher DNA fragmentation. CONCLUSION: Abnormally high (LDLR(-/-) islets) or low cholesterol content (WT islets treated with MßCD) alters both GSIS and Ca(2+) handling. Normalization of cholesterol improves Ca(2+) handling and insulin secretion in LDLR(-/-) islets.

Transmission of Citrus leprosis virus C by Brevipalpus phoenicis (Geijskes) to Alternative Host Plants Found in Citrus Orchards.

The equivalent of US$75 million is spent each year in Brazil to control Brevipalpus phoenicis, a mite vector of Citrus leprosis virus C (CiLV-C). In this study, we investigated the possibility that hedgerows and windbreaks normally found in citrus orchards could host CiLV-C. Mites confined by an adhesive barrier were reared on sweet orange fruit with leprosis symptoms then were transferred to leaves of Hibiscus rosa-sinensis, Malvaviscus arboreus, Grevilea robusta, Bixa orellana, and Citrus sinensis. Ninety days post infestation, the descendant mites were transferred to Pera sweet orange plants to verify the transmissibility of the virus back to citrus. Nonviruliferous mites which had no feeding access to diseased tissue were used as controls. Local chlorotic or necrotic spots and ringspots, symptoms of leprosis disease, appeared in most plants tested. Results generated by reversetranscription polymerase chain reaction with primers specific for CiLV-C and by electron microscope analyses confirmed the susceptibility of these plants to CiLV-C.

Morphine-induced changes in opioid sensitivity in postpartum females: a unique progesterone response.

Opioid peptides play an important role in maternal behaviour, as well as in physiological and pathological phenomena involving motivation. Daily 3.5 mg/kg doses of morphine from days 17-21 of pregnancy are able to change the expression of maternal behaviour patterns. However, the role of hormones on such opioid behavioural actions remains to be determined. The present study investigated the endocrine responses to this morphine treatment. Corticosterone, progesterone, oestradiol and prolactin serum concentrations were measured after each morphine injection. No significant differences were found in corticosterone, oestradiol or prolactin serum concentrations. The results suggest that the treatment was unable to promote different effects, other than those caused by saline injections. In morphine-treated animals, however, progesterone concentrations were consistently and significantly increased from days 18-20 of treatment. Thus, because this behavioural meaningful opioidergic stimulation during late pregnancy affects progesterone levels, the findings of the present study raise the hypothesis that this hormone may play a role in morphine-induced changes in opioid sensitivity during late pregnancy and early lactation.

Pregnancy restores insulin secretion from pancreatic islets in cafeteria diet-induced obese rats.

Insulin resistance during pregnancy is counteracted by enhanced insulin secretion. This condition is aggravated by obesity, which increases the risk of gestational diabetes. Therefore, pancreatic islet functionality was investigated in control nonpregnant (C) and pregnant (CP), and cafeteria diet-fed nonpregnant (Caf), and pregnant (CafP) obese rats. Isolated islets were used for measurements of insulin secretion (RIA), NAD(P)H production (MTS), glucose oxidation ((14)CO(2) production), intracellular Ca(2+) levels (fura-2 AM), and gene expression (real-time PCR). Impaired glucose tolerance was clearly established in Caf and CafP rats at the 14th wk on a diet. Insulin secretion induced by direct depolarizing agents such as KCl and tolbutamide and increasing concentrations of glucose was significantly reduced in Caf, compared with C islets. This reduction was not observed in islets from CP and CafP rats. Accordingly, the glucose oxidation and production of reduced equivalents were increased in CafP islets. The glucose-induced Ca(2+) increase was significantly lower in Caf and higher in CafP, compared with all other groups. CP and CafP islets demonstrated an increased Ca(2+) oscillation frequency, compared with both C and Caf islets, and the amplitude of oscillations was augmented in CafP, compared with Caf islets. In addition, Ca(v)alpha1.2 and SERCA2a mRNA levels were reduced in Caf islets. Ca(v)alpha1.2, but not SERCA2a, mRNA was normalized in CafP islets. In conclusion, cafeteria diet-induced obesity impairs insulin secretion. This alteration is related to the impairment of Ca(2+) handling in pancreatic islets, in especial Ca(2+) influx, a defect that is reversed during pregnancy allowing normalization of insulin secretion.

Ovarian function in Nelore (Bos taurus indicus) cows after post-ovulation hormonal treatments.

Maternal recognition of pregnancy in the cow requires successful signaling by the conceptus to block luteolysis. Conceptus growth and function depend on an optimal uterine environment, regulated by luteal progesterone. The objective of this study was to test strategies to optimize luteal function, as well as prevent a dominant follicle from initiating luteolysis. Nelore (Bos taurus indicus) beef cows (n=40) were submitted to a GnRH/PGF(2alpha)/GnRH protocol. Cows that ovulated from a dominant ovarian follicle (ovulation=Day 0) were allocated to receive: no additional treatment (G(C); n=7); 3000IU of hCG on Day 5 (G(hCG); n=5); 5mg of estradiol-17beta on Day 12 (G(E2); n=6); or 3000IU of hCG on Day 5 and 5mg of estradiol-17beta on Day 12 (G(hCG/E2); n=5). Ultrasonographic imaging of the ovaries, assessment of plasma progesterone concentration, and detection of estrus were done daily from Day 5 to the day of subsequent ovulation. Treatment with hCG induced an accessory CL, increased CL volume, and plasma progesterone concentration throughout the luteal phase (P<0.01). Estradiol-17beta induced atresia and recruitment of a new wave of follicular growth; it eliminated a potentially estrogen-active, growing ovarian follicle within the critical period for maternal recognition of pregnancy, but it also hastened luteolysis (Days 16 or 17 vs. Days 18 or 19 in non-treated cows). In conclusion, the approaches tested enhanced luteal function (hCG) and altered ovarian follicular dynamics (estradiol-17beta), but were unable to extend the life-span of the CL in Nelore cows.

Follicular dynamics in heifers during pre-pubertal and pubertal period kept under two levels of dietary energy intake.

The objective of this study was to characterize follicular dynamics in pre-pubertal, pubertal and post-pubertal periods, as well as the effect of high-energy intake on follicular development and age at puberty in heifers. Thirty-one Nelore (Bos indicus) heifers, 6 months old, were randomly assigned to receive two different diets: one of low (GI) and other of high dietary energy intake (GII). Animals were evaluated in relation to body weight gain by being weighed every 21 days. Heifers were evaluated every other day by real-time linear ultrasonography to characterize ovarian structures development from weaning to post-pubertal period. Blood samples were collected to determine plasmatic concentrations of progesterone by RIA method. The ovulation was determined when progesterone concentrations were >1 ng/mL in three consecutive samples, and by ultrasound images of corpus luteum; and oestrous behaviour in some animals. Age at puberty differed among heifers of GII (17.00 +/- 0.46 months) compared with heifers of GI (19.87 +/- 0.47 months; p < or = 0.05). Maximum size of the dominant follicles at pre-pubertal period was greater in GII heifers than in GI (10.52 +/- 0.33 and 9.76 +/- 0.15 mm, respectively; p < or = 0.05). As heifers approached first ovulation time, size of dominant follicle increased (11.75 +/- 0.37 mm for GI and 12.52 +/- 0.91 mm for GII; p < or = 0.05). Body weight at puberty was not different in both groups (302.33 +/- 27.31 kg for GI and 326.19 +/- 27.78 kg for GII heifers; p > 0.05). We conclude that animals receiving high dietary energy intake attained the puberty earlier and the development of follicles were different than in low dietary energy intake.

Pathologic study of a fatal case of dengue-3 virus infection in Rio de Janeiro, Brazil.

Dengue hemorrhagic fever (DHF) is a severe febrile disease, characterized by abnormalities in hemostasis and increased vascular permeability, which in some cases results in hypovolemic shock syndrome and in dengue shock syndrome. The clinical features of DHF include plasma leakage, bleeding tendency and liver involvement. We studied the histopathological features of a fatal case of dengue-3 virus infection. The patient, a 63-year old male, presented with an acute onset of severe headache, myalgia and maculopapular rash. Tissue fragments (liver, spleen, lung, heart, kidney and lymph nodes) were collected for light microscopy studies and stained by standard methods. Histopathology revealed severe tissue damage, caused by intense hemorrhage, interstitial edema and inflammation. Some tissue sections were also processed with the immunoperoxidase reaction, which revealed the dengue viral antigen. Dengue-3 virus was isolated and identified with electron microscopy in a C6/36 cell culture inoculated with the patient's serum. Viral particles were detected in the infected cell culture.

Pathologic study of a fatal case of dengue-3 virus infection in Rio de Janeiro, Brazil

Dengue hemorrhagic fever (DHF) is a severe febrile disease, characterized by abnormalities in hemostasis and increased vascular permeability, which in some cases results in hypovolemic shock syndrome and in dengue shock syndrome. The clinical features of DHF include plasma leakage, bleeding tendency and liver involvement. We studied the histopathological features of a fatal case of dengue-3 virus infection. The patient, a 63-year old male, presented with an acute onset of severe headache, myalgia and maculopapular rash. Tissue fragments (liver, spleen, lung, heart, kidney and lymph nodes) were collected for light microscopy studies and stained by standard methods. Histopathology revealed severe tissue damage, caused by intense hemorrhage, interstitial edema and inflammation. Some tissue sections were also processed with the immunoperoxidase reaction, which revealed the dengue viral antigen. Dengue-3 virus was isolated and identified with electron microscopy in a C6/36 cell culture inoculated with the patient's serum. Viral particles were detected in the infected cell culture.

Optic neuromyelitis syndrome in Brazilian patients.

OBJECTIVES: To report the clinical features and outcome of 24 Brazilian patients with optic neuromyelitis syndrome (ONM); discuss the underlying pathological events associated with the ONM syndrome; review the nosological situation of ONM in the group of inflammatory and demyelinating diseases of the central nervous system. PATIENTS AND METHODS: Patients with ONM treated at the Hospital da Lagoa, Rio de Janeiro were studied. Demographic, clinical, magnetic resonance imaging, cerebrospinal fluid, and pathological data were analysed. RESULTS: The study consisted of 20 women, four men of whom 10 were white and 14 Afro-Brazilians. Clinical course was recurrent in 22 cases and monophasic in two. Neurological manifestations at inclusion were: sensory impairment (66%), bilateral (41.6%) or unilateral blindness (20.8%), paraplegia or quadriplegia (37.5%). The EDSS was moderate/severe in 70.8%. The underlying pathological events were respectively pulmonary tuberculosis and upper respiratory infection in the two monophasic cases; in the 22 recurrent ONM patients: pulmonary tuberculosis (3), neurocysticercosis (1), polyarteritis nodosa (1), antinuclear antibody and rheumatoid factor (1), antiphospholipid antibody primary syndrome (1), diabetes mellitus (1), hypothyroidism (1), and amenorrhea-galactorrhea (4). Normal cerebrospinal fluid was found in 52% and an inflammatory profile in 48%. Only four recurrent ONM white patients had brain and spinal cord magnetic resonance imaging and cerebrospinal fluid findings compatible with the diagnosis of multiple sclerosis. Large lesions were seen in 62% of spinal magnetic resonance images. Six of 12 recurrent ONM Afro-Brazilian died. There were no statistical differences in the demographic data of the two ethnic groups. Afro-Brazilians were significantly more severely impaired and had a higher mortality rate than the white patients. CONCLUSION: These cases were classified as follows: two monophasic acute disseminated encephalomyelitis; one recurrent disseminated encephalomyelitis; three recurrent ONM associated with Hughes syndrome, autoantibodies and polyarteritis nodosa; six recurrent ONM with endocrinopathies; and finally, four multiple sclerosis cases. The remaining cases were not associated with any other condition. It would seem clear that ONM is a syndrome rather than a single disease.

iceA genotypes of Helicobacter pylori strains isolated from Brazilian children and adults.

Data concerning the geographic distribution of iceA alleles are scarce, and information on the association of the gene with the disease is rare and still controversial. Furthermore, no such study has been developed in Brazil, where duodenal ulcer and gastric adenocarcinoma are very common. We investigated, by PCR, the frequency of iceA alleles and cagA status in Helicobacter pylori strains isolated from 142 patients (62 children and 80 adults; 66 female; mean age, 30.0 years; age range, 3 to 78 years) with gastritis, duodenal ulcer, or gastric adenocarcinoma. iceA was identified in bacterium samples obtained from all patients. Eleven (7.7%) of them were infected with multiple strains. Among the patients with nonmixed infection, iceA2 allele was detected in 118 (90.1%). iceA2 allele was associated with ulcer (P = 0.02) and with carcinoma (P = 0.001). iceA2 amplicons of 229, 334, or 549 bp were detected, but none of them was associated with the patient's disorder. iceA2 strains were more frequent in patients older than 7 years (P = 0.001). The gene was also more frequent in strains obtained from males (P = 0.02). cagA was more common in strains obtained from carcinoma (P = 0.0008) and ulcer patients (P < 0.006). cagA-positive strains were more frequent in children older than 7 years (P < 0.003). No association between cagA status and sex was found (P = 0.28). In conclusion, we think iceA should not be used as a reliable marker for predicting the clinical outcome of H. pylori infection.

Whipple's disease. Report of five cases with different clinical features.

Whipple's disease (WD) is a rare systemic disease of infectious etiology which involves the small intestine but can virtually affect any organ. We present here five cases (four males and one female) ranging in age from 20 to 59 years. All patients had intestinal involvement associated or not with clinical manifestations linked to this organ. Vegetation in the tricuspid valve was observed in one patient, suggesting endocarditis caused by Tropheryma whippelii, with disappearance of the echocardiographic alterations after treatment. In one of the male patients the initial clinical manifestation was serologically negative spondylitis, with no diarrhea occurring at any time during follow-up. Ocular involvement associated with intestinal malabsorption and significant weight loss were observed in one case. In the other two cases, diarrhea was the major clinical manifestation. All patients were diagnosed by histological examination of the jejunal mucosa and, when indicated, of extraintestinal tissues by light and electron microscopy. After antibiotic treatment, full remission of symptoms occurred in all cases. A control examination of the intestinal mucosa performed after twelve months of treatment with sulfamethoxazole-trimethoprim revealed the disappearance of T. whippelii in four patients. The remaining patient was lost to follow-up.