Could formaldehyde induce mutagenic and cytotoxic effects in buccal epithelial cells during anatomy classes?

BACKGROUND: Due to increased formaldehyde exposure, carcinogenic to humans, several researches have been studying the potential toxicity and the safe levels for human beings. The aim of this study was to investigate mutagenicity and cytotoxicity in buccal epithelial exfoliated cells (BEC) of students subjected to formaldehyde (FA) during anatomy classes. MATERIAL AND METHODS: BEC were collected periodically from 17 volunteers of undergraduate programs, who had participated in practical anatomy classes, before and after FA exposure. Cells were stained according to Feulgen method and then micronucleus test was applied. A total of 1,500 cells were assessed per individual in this study for the micronucleus frequency and other parameters of cytotoxicity. RESULTS: There was statistically significant increase in number of micronucleated BEC after FA exposure (after 1 month p=.034 and after 3.5 months p=.017). However, FA exposure caused no significant increase in other nuclear alterations closely related to cytotoxicity (p≥.05). CONCLUSIONS: FA induced mutagenicity during anatomy classes. Cell death increased, but it was not statistically significant. Efforts have to be made to improve air quality and reduce exposures during anatomy classes.

Helicobacter pylori infection is high in paediatric nonulcer dyspepsia but not associated with specific gastrointestinal symptoms.

AIM: The association between Helicobacter pylori infection and gastrointestinal symptoms is debatable in childhood. We examined the potential relationship between H. pylori infection and gastrointestinal symptoms in Brazilian children with nonulcer dyspepsia. METHODS: This prospective observational study analysed 240 Brazilian children and adolescents (68.7% girls) with chronic nonulcer dyspepsia, who underwent upper gastrointestinal endoscopy and biopsy. Their mean age was 9.8 years (range 4-17). Upper gastrointestinal symptoms, including abdominal pain, nausea, burning, early satiety, belching and weigh loss, were evaluated by a questionnaire and H. pylori infection was determined by histopathology of gastric biopsies. RESULTS: H. pylori infection was identified in 123/240 patients (52%). There was no significant association between the H. pylori infection and gastrointestinal symptoms and no relationship between the infection and abdominal pain or pain characteristics. However, nausea was significantly associated with the H. pylori infection, with an odds ratio of 1.76 and 95% confidence interval of 1.1-2.94 p < 0.03. Symptoms lasting longer than 12 months were significantly more frequent in children with pangastritis than in those with antral gastritis (p < 0.05). CONCLUSION: The prevalence of H. pylori infection was high in Brazilian children with nonulcer dyspepsia, but was not associated with specific signs and symptoms, except for nausea.

HydroCalc Proteome: a tool to identify distinct characteristics of effector proteins.

Bacterial pathogenicity is associated with secretion of effector proteins into intra- and extracellular spaces. These proteins interfere with cellular processes such as inhibition of phagosome-lysosome fusion, induction of apoptosis and autophagy, activation and suppression of kinases, regulation of receptor activity, and modulation of transcription factors. Knowledge regarding the characteristics of these proteins would assist in pathogenicity studies, and help to identify possible and novel targets for antibacterial drugs. Amino acid hydropathy is a property that can affect behavior patterns in effector proteins. The HydroCalc Proteome tool analyzes total hydropathy, average hydropathy, C-terminal hydropathy, C-terminal load, and basic polar amino acids at the C-terminus. These five properties could contribute to the identification of proteins with an effector potential. HydroCalc Proteome is a web tool that provides a simple interface for the analysis of hydropathy properties in proteins. This tool permits the analysis of a single protein or even the complete proteome, which cannot be achieved by using other hydropathy tools. The tool displays the result of five properties related to effector proteins in a single table. The HydroCalc Proteome (www.gmb.bio.br/hydrocalc) is a powerful tool for protein analysis, and can contribute to the study of effector proteins.

Hidden prevalence of chronic kidney disease in hypertensive patients: the strategic role of primary health care.

OBJECTIVE: To identify the hidden prevalence of chronic kidney disease (CKD) in hypertensive patients. STUDY DESIGN: Cross-sectional study of individuals with systemic arterial hypertension (SAH) who were registered for primary health care (PHC). METHODS: In total, 293 individuals participated. Data were collected through interviews, as well as biochemical and anthropometric assessments. The CKD-EPI formula was used to identify the occurrence of CKD. Pearson's chi-squared test or Fisher's exact test were used to compare proportions. Prevalence ratios were estimated with a confidence interval of 95% for associations between the explanatory variables and CKD. RESULTS: Most of the individuals assessed were female (74%), elderly (69%), with a low income (90%), low education levels (84%) and overweight (66.9%). A CKD prevalence of 38.6% (95% CI: 33.0-44.2) was found and approximately 14% were at an advanced stage of the disease. Upon comparison of the variables in the different stages of CKD, statistically significant association could be suggested between CKD and age, education, alcohol intake, overweight individuals, cardiovascular risk, abnormal creatinine and abnormal microalbuminuria. When the prevalence ratio was assessed, association could be suggested between CKD and age, and CKD and creatinine. CONCLUSION: The high hidden prevalence of CKD confirms the need to train health professionals involved in the treatment of SAH through PHC, enabling the prevention and diagnosis of CKD in its early stages.

Occupational exposure to pesticides deregulates systemic cortisol levels in women with breast cancer and correlates with poor prognosis features.

Pesticides have been pointed out as hormone disruptors and may significantly affect the prognosis of hormone-dependent diseases such as breast cancer (BC). Here, we investigated the impact of occupational pesticide exposure on systemic cortisol levels in female rural workers diagnosed with BC. Occupational exposure was assessed by interviews with a standardized questionnaire. Plasma samples (112 from pesticide-exposed women and 77 from unexposed women) were collected in the afternoon, outside the physiological cortisol peak, and analyzed by a chemiluminescent paramagnetic immunoassay for the quantitative determination of cortisol levels in serum and plasma. The results from both groups were categorized according to patients' clinicopathological and exposure data. BC pesticide-exposed women presented higher levels of cortisol than the unexposed. Higher cortisol levels were also detected in the exposed group with more aggressive disease (triple-negative BC), with tumors over 2 cm, with lymph node metastases, and with high risk of disease recurrence and death. These findings demonstrated that there is an association between pesticide exposure and BC that affected cortisol levels and correlated to poor disease prognosis.

Footwear designed to enhance energy return improves running economy compared to a minimalist footwear: does it matter for running performance?

The present study compared the effects of a footwear designed to enhance energy return (thermoplastic polyurethane, TPU) vs minimalist shoes on running economy (RE) and endurance performance. In this counterbalanced and crossover design study, 11 recreational male runners performed two submaximal constant-speed running tests and two 3-km time-trials with the two shoe models. Oxygen uptake was measured during submaximal constant-speed running tests in order to determine the RE at 12 km/h and oxygen cost of running (CTO2) at individual average speed sustained during the 3-km running time-trials wearing either of the two shoes. Our results revealed that RE was improved (2.4%) with TPU shoes compared with minimalist shoes (P=0.01). However, there was no significant difference for CTO2 (P=0.61) and running performance (P=0.52) comparing the TPU (710±60 s) and the minimalist (718±63 s) shoe models. These novel findings demonstrate that shoes with enhanced mechanical energy return (i.e. TPU) produced a lower energy cost of running at low (i.e., 12 km/h) but not at high speeds (i.e., average speed sustained during the 3-km running time-trial, ∼15 km/h), ultimately resulting in similar running performance compared to the minimalist shoe.

Purine nucleoside phosphorylase activity and expression are upregulated in sites affected by periodontal disease.

BACKGROUND AND OBJECTIVE: Purine nucleoside phosphorylase (PNP) is an enzyme that catalyzes the reversible phosphorolysis of purine nucleosides, playing a key role in the purine salvage pathway. Activated T cells seem to rely heavily on PNP to remain functionally active and are particularly sensitive to PNP deficiency. The role of PNP in periodontal tissues has not been characterized thus far. The aim of this study therefore was to assess the activity and expression of PNP in the gingival tissues of periodontitis patients. MATERIAL AND METHODS: Ten patients consecutively admitted for treatment had their periodontal clinical variables recorded and their gingival crevicular fluid collected. After periodontal treatment the patients were seen once a month for plaque and bleeding control, and had their periodontal variables recorded and gingival crevicular fluid collected at 90 and 180 d. Purine nucleoside phosphorylase-specific activity was assessed using a spectrophotometer through the addition of the PNP substrate analog 2-amino-6mercapto-7-methyl purine riboside to the gingival crevicular fluid. In parallel, PNP expression was assessed by immunohistochemistry and real-time PCR in gingival biopsies and cell culture. RESULTS: Purine nucleoside phosphorylase activity was higher in the gingival crevicular fluid of periodontally diseased sites, which was positively correlated with improvements of the clinical variables. Treatment of periodontal disease induced a striking decrease of PNP activity in periodontally diseased sites. Expression of PNP was more pronounced in mononuclear cells and endothelial cells of the gingiva, and the mRNA levels were 5.7-fold higher in inflamed tissues compared with control samples. CONCLUSION: Purine nucleoside phosphorylase activity and expression are upregulated in periodontally diseased sites and can be detected in the gingival crevicular fluid.

Intussusception in adults: a retrospective study.

OBJECTIVE: Intestinal intussusception in adult patients is rare. In contrast with paediatric patients, it is usually secondary to a definable lesion, often malignant. The purpose of this study was to determine the causes and the management of intussusception in adult patients. METHOD: A retrospective review was performed looking at patients over 18 years with intestinal intussusception who were admitted to a tertiary university hospital from 1997 to 2007. RESULT: There were 16 patients (out of whom 10 were female subjects) of mean age 49 years (range 19-76). All presented with abdominal pain and in seven (46.6%) patients, this was acute. The diagnosis of intussusception was correctly made preoperatively in eight (50%) patients. Six (37.5%) patients had the lead point for the intussusception at the ileocaecal valve, five (31.25%) in the small bowel and five (31.25%) had a colonic lead point. An anatomical cause was found in 14 (87.5%). In two (12.5%), the intussusception occurred in the postoperative period without any definable lesion. Half the patients had a malignant neoplasm. All patients underwent surgery. In 14 (87.5%) patients, this was by resection and in two (12.5%), a reduction with no resection was carried out. CONCLUSION: The features of intussusception may be nonspecific and the diagnosis is often made only during laparotomy. An identifiable organic lesion is present in most cases. En bloc resection is recommended for ileocaecal and colocolic intussusception.

Canal transportation and centring ability of RaCe rotary instruments.

AIM: Evaluate, through computerized tomography, canal transportation and centring ability of RaCe rotary instruments after preparation of mesiobuccal root canals in maxillary molar teeth. METHODOLOGY: Twenty-seven teeth were submitted to three cone beam tomographic analyses, one preoperatively, and two after preparation with file size 35, .02 taper and size 50, .02 taper. Canal transportation and centring ability were measured with reference to the distance between the noninstrumented portion of the root canals and the mesial and distal periphery of the root, compared with images obtained after the preparation with size 35 and 50 instruments. RESULTS: Canal transportation after preparation with the size 35 file was 0.030 +/- 0.253 mm and after the size 50 file was 0.057 +/- 0.317 mm. The centring ratio values after preparation with the size 35 file was 0.42 +/- 0.32 and after the size 50 file was 0.54 +/- 0.29, with no significant statistical difference between the groups. CONCLUSIONS: RaCe instruments allowed the preparation of curved root canals with preparation diameters larger than those normally used with minimal canal transportation and adequate centring ability.

Occupational exposure to pesticides deregulates systemic cortisol levels in women with breast cancer and correlates with poor prognosis features

Pesticides have been pointed out as hormone disruptors and may significantly affect the prognosis of hormone-dependent diseases such as breast cancer (BC). Here, we investigated the impact of occupational pesticide exposure on systemic cortisol levels in female rural workers diagnosed with BC. Occupational exposure was assessed by interviews with a standardized questionnaire. Plasma samples (112 from pesticide-exposed women and 77 from unexposed women) were collected in the afternoon, outside the physiological cortisol peak, and analyzed by a chemiluminescent paramagnetic immunoassay for the quantitative determination of cortisol levels in serum and plasma. The results from both groups were categorized according to patients' clinicopathological and exposure data. BC pesticide-exposed women presented higher levels of cortisol than the unexposed. Higher cortisol levels were also detected in the exposed group with more aggressive disease (triple-negative BC), with tumors over 2 cm, with lymph node metastases, and with high risk of disease recurrence and death. These findings demonstrated that there is an association between pesticide exposure and BC that affected cortisol levels and correlated to poor disease prognosis.

Evaluation of an environmentally sustainable UV-assisted water treatment system for the removal of Bacillus globigii spores in water.

Development of greener water treatment technologies is important for the production of safe drinking water and water security applications, such as decontamination. Chlorine assisted disinfection is common and economical, but can generate disinfection byproducts (DBPs) that may be of health concern. DBPs are formed due to the reaction of chlorine with naturally occurring organic and inorganic substances in water. Currently, various innovative technologies are being developed as alternative approaches for preventing DBPs during water treatment. In this study, we evaluated the effectiveness of a novel combination of high efficiency flow filtration and UV disinfection treatment system for the removal of Bacillus globigii (B. globigii) spores in water. The filtration system consists of a charged membrane filter (CMF) that not only helps to remove suspended particles but also reduces the impact of other impurities including bio organisms. In order to get most performance details, the CMF was evaluated at clean, half-life, and end of life (EOL) conditions along with 100% UV transmittance (UVT). In addition, the effectiveness of the UV system was evaluated as a stand alone system at 100% and 70% EOL intensity. The study was conducted at the US EPA's Test and Evaluation (T&E) Facility in Cincinnati, OH, using B. globigii, a surrogate for B. anthracis spores. This non-chemical environmentally-friendly CMF/UV combination system and the stand alone UV unit showed greater than 6.0 log removal of B. globigii during the tests.

A combination of nutrition and genetics is able to reduce age at puberty in Nelore heifers to below 18 months.

Nelore heifers usually begin their reproductive life at ⩾24 months of age mainly due to suboptimal nutritional conditions and genetics. This study aimed to determine the effect of expected progeny difference (EPD) for age at first calving and average daily gain (ADG) on puberty in Nelore (Bos taurus indicus) heifers. A total of 58 weaned heifers (initial BW=174±6 kg; age=9±1 months) were allocated into 28 feedlot pens. Heifers were born from four sires, of which two had low EPD for age at first calving (L; n=33) and two had high EPD for age at first calving (H; n=25). Then, heifers of each EPD were randomly assigned to high ADG (HG; 0.7 kg) or low ADG (LG; 0.3 kg), resulting in four treatments: heifers from L sires were submitted to either HG (LHG; n=17) or LG (LLG; n=16), and heifers from H sires were submitted to either HG (HHG; n=12), or LG (HLG; n=13). The HG heifers were fed a 75% grain diet, whereas the LG heifers received 93% of forage in their diet. Blood samples were collected at 9, 14, 18, 24 and 28 months of age for IGF1 and leptin determination. There was a treatment effect (P<0.01) on the proportion of heifers that attained puberty by 18 (62%, 0%, 0% and 0%), 24 (100%, 6%, 54% and 0%) or 36 (100%, 100%, 100% and 38%) months of age for LHG, LLG, HHG and HLG treatments, respectively. In addition, mean age at puberty was different across treatments (P<0.01). Heifers from the LHG achieved puberty at the earliest age when compared with cohorts from other treatments (18.1, 28.9, 23.9 and 34.5 months for LHG, LLG, HHG and HLG, respectively). Serum IGF1 concentrations were higher for L heifers compared with H cohorts at 9, 14, 18, 24 and 28 months of age (P<0.01; treatment×age interaction), whereas circulating leptin concentrations were higher (P<0.01; age effect) as heifers became older, regardless of the treatments. In conclusion, only Nelore heifers with favorable genetic merit for age at first calving were able to attain puberty by 18 months of age. In heifers with unfavorable genetic merit for age at first calving, supplementary feeding to achieve high ADG was unable to shift the age at puberty below 24 months.

Pseudomyxoma peritonei arising from colonic polyps.

AIMS: Pseudomyxoma peritonei may have as its primary site a mucinous gastrointestinal adenoma or carcinoma that gains access to the peritoneal cavity. This manuscript describes this disease arising from a benign or malignant colonic polyp. METHODS: From a database of over 1000 pseudomyxoma peritonei patients and colorectal carcinomatosis patients, three cases were identified in which the primary tumor site was a colonic polyp. The clinical history and course of these patients were studied. RESULTS: In a review of the clinical management of these patients, all three had an event whereby neoplastic cells from the surface of the colonic polyp could have gained access to the free peritoneal cavity. The patients developed the characteristic pseudomyxoma peritonei syndrome. All three patients were treated with cytoreductive surgery plus perioperative hyperthermic intraperitoneal chemotherapy. CONCLUSIONS: Colonic polyps can serve as a source of dysplastic cells whereby pseudomyxoma peritonei can result. Caution to prevent seeding to the free peritoneal cavity during surgery for colonic polyps should be observed. If pseudomyxoma peritonei develops, cytoreductive surgery and perioperative intraperitoneal chemotherapy should be considered for treatment.

Footwear designed to enhance energy return improves running economy compared to a minimalist footwear: does it matter for running performance?

The present study compared the effects of a footwear designed to enhance energy return (thermoplastic polyurethane, TPU) vs minimalist shoes on running economy (RE) and endurance performance. In this counterbalanced and crossover design study, 11 recreational male runners performed two submaximal constant-speed running tests and two 3-km time-trials with the two shoe models. Oxygen uptake was measured during submaximal constant-speed running tests in order to determine the RE at 12 km/h and oxygen cost of running (CTO2) at individual average speed sustained during the 3-km running time-trials wearing either of the two shoes. Our results revealed that RE was improved (2.4%) with TPU shoes compared with minimalist shoes (P=0.01). However, there was no significant difference for CTO2 (P=0.61) and running performance (P=0.52) comparing the TPU (710±60 s) and the minimalist (718±63 s) shoe models. These novel findings demonstrate that shoes with enhanced mechanical energy return (i.e. TPU) produced a lower energy cost of running at low (i.e., 12 km/h) but not at high speeds (i.e., average speed sustained during the 3-km running time-trial, ∼15 km/h), ultimately resulting in similar running performance compared to the minimalist shoe.

Late postoperative follow-up of patients submitted to subtotal splenectomy.

Subtotal splenectomy preserving the upper splenic pole vascularized only by the splenogastric vessels has been performed by us in 91 patients since 1984. This procedure was combined with central splenorenal shunt or portal variceal disconnection to treating schistosomatic portal hypertension (n = 67); it was combined with distal pancreatectomy to treat pancreatic cystadenoma (n = 1), and it was carried out for severe splenic trauma (n = 14), and to control severe Gaucher's disease (n = 4) and myeloid metaplasia due to myelofibrosis (n = 5). All patients are alive. In the present paper, we present the late postoperative follow up of 32 patients operated in a period that ranges from 1 to 12 years. All patients are satisfied with the operation. Increased counts of white blood cell (n = 10) and platelets (n = 7) were the only hematological alterations. Esophageal varices were present in 23 of 27 patients operated due to portal hypertension, but all of them were shorter than in the preoperative period. The ultrasound confirmed the presence of the splenic remnant (30 of 32) without significant size changes. Splenic scintigraphies were positive in 30 of 32 patients. Subtotal splenectomy seems to be a safe procedure that can be useful in portal hypertension, some metabolic and hematological diseases, and benign growth of the distal pancreas.

Study of different media for production of penicillin G acylase from Bacillus megaterium ATCC 14945.

In this study, several fermentation media were tested for the production of penicillin G acylase (PGA) using Bacillus megaterium. The carbon sources studied were glucose and lactose. The nitrogen sources studied were enzymatic casein hydrolysates produced with proteases of different specificities. The replacement of glucose with cheese whey and the addition of free amino acids in the PGA production were also tested. The results showed a strong correlation between the nitrogen source and enzyme yield and the presence of glucose repression. The highest enzyme concentration achieved was 138 IU/L using casein hydrolyzed with 0.6 L of Alcalase and cheese whey.

A hybrid neural network algorithm for on-line state inference that accounts for differences in inoculum of Cephalosporium acremonium in fed-batch fermentors.

One serious difficulty in modeling a fermentative process is the forecasting of the duration of the lag phase. The usual approach to model biochemical reactors relies on first-principles, unstructured mathematical models. These models are not able to take into account changes in the process response caused by different incubation times or by repeated fedbatches. To overcome this problem, we have proposed a hybrid neural network algorithm. Feedforward neural networks were used to estimate rates of cell growth, substrate consumption, and product formation from on-line measurements during cephalosporin C production. These rates were included in the mass balance equations to estimate key process variables: concentrations of cells, substrate, and product. Data from fed-batch fermentation runs in a stirred aerated bioreactor employing the microorganism Cephalosporium acremonium ATCC 48272 were used. On-line measurements strongly related to the mass and activity of the cells used. They include carbon dioxide and oxygen concentrations in the exhausted gas. Good results were obtained using this approach.

[Delayed (modified) oral cholecystography in the study of biliary dyskinesia]. / Colecistografia oral retardada (modificada) no estudo da discinesia biliar.

Biliary dyskinesia is difficult to be either diagnosed or treated. A modified oral cholecystography technique has been tested to make it suitable for studying such gallbladder disease. Routine oral cholecystography was performed and then two other roentgenograms were taken both 24 and 48 hours after it. In our opinion, further studies should be performed whenever gallbladder visualization lasts longer than 48 hours even in order to indicate surgery.

In vitro action of various bleaching agents on the microhardness of human dentin.

The authors verified a decrease in human dentin microhardness after application of the following bleaching agents for 72 hours: sodium perborate+water, sodium perborate + 3% hydrogen peroxide, sodium perborate + 30% hydrogen peroxide, Endoperox (crystallized hydrogen peroxide), Proxigel (carbimide peroxide), and 30% hydrogen peroxide. Sodium perborate+water and sodium perborate + 3% hydrogen peroxide caused less of a decrease in dentin microhardness than Endoperox, Proxigel and 30% hydrogen peroxide which caused the greatest decreases in dentin microhardness. Sodium perborate + 30% hydrogen peroxide fell into a statistically intermediate position.

In vitro study of cervical enamel projection in human molars.

The authors studied the cervical enamel projection (CEP) in 1903 extracted permanent molars. The incidence of CEP was greater on the buccal and lingual surfaces than on the mesial and distal surfaces and occurred more frequently in maxillary molars than in mandibular molars.