Infiltration OF 5Y-PSZ with thermally compatible glass: Strength, microstructure and failure mode analyses

This study set out to develop a thermally compatible glass to be infiltrated into zirconia partially stabilized by yttrium oxide (5Y-PSZ), to characterize it, and to evaluate its structural reliability and mechanical behavior. 5Y-PSZ zirconia discs (N = 90), dimensions 1.5 mm × 15 mm were produced, polished with #600 alumina oxide and #1200 silicon carbide sandpaper in a polisher. Three groups of 5Y-PSZ discs were assigned (n = 30): Zctrl: as sintered zirconia, Zinf-comp: glass-infiltrated zirconia on the occlusal surface, and sintered, and Zinf-tens: glass-infiltrated zirconia on the cementing surface and sintered; for biaxial flexural strength testing (ISO 6872:2015). A gel was synthesized via the sol-gel method and applied to the ceramic surface. Mechanical assay data (MPa) were evaluated via Weibull analysis (α = 5%) and specimens via X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), and fractographic analysis. The Zinf-tens group showed a characteristic strength of 824 MPa and m = 9.9; Zinf-comp 613 MPa and m = 10.2; Zctrl 534 MPa and m = 8; all groups differed statistically (σ₀). However, they were similar in structural homogeneity (m). XRD showed 20-50 μm of infiltration, which means dissolution of part of the yttrium and reduction in the size of the cubic grains. In addition, the Zinf-tens group presented a failure origin from inside the material. The developed glass infiltrated into zirconia partially stabilized by yttrium oxide, increasing its characteristic strength and structural homogeneity by reducing surface defects and changing the failure mode.

Effectiveness of chlorthalidone/amiloride versus losartan in patients with stage I hypertension and diabetes mellitus: results from the PREVER-treatment randomized controlled trial

AIMS

To compare the blood pressure (BP)-lowering efficacy of a chlorthalidone/amiloride combination pill with losartan, during initial management of JNC 7 Stage I hypertension in patients with type 2 diabetes mellitus.

METHODS

In an a priori subgroup analysis of a randomized, double-blind, controlled trial, volunteers aged 30-70 years, with stage I hypertension and diabetes mellitus, were randomized to 12.5/2.5 mg of chlorthalidone/amiloride (N = 47) or 50 mg of losartan (N = 50), and followed for 18 months in 21 clinical centers. If BP remained uncontrolled after three months, study medication dose was doubled, and if uncontrolled after six months, amlodipine (5 and 10 mg) and propranolol (40 and 80 mg BID) were added as open label drugs in a progressive fashion.

RESULTS

Systolic BP decreased to a greater extent in participants allocated to diuretics compared to losartan (P < 0.001). After 18 months of follow-up, systolic BP was 128.4 ± 10.3 mmHg in the diuretic group versus 133.5 ± 8.0 in the losartan group (P < 0.01). In the diuretic group, 36 out of 43 participants (83.7%) had a JNC 7 normal BP, compared to 31/47 (66%) in the losartan group (P = 0.089). Serum cholesterol was higher in the diuretic arm at the end of the trial. Other biochemical parameters and reports of adverse events did not differ by treatment.

CONCLUSIONS

Treatment of hypertension based on a combination of chlorthalidone and amiloride is more effective for BP lowering compared to losartan in patients with diabetes mellitus and hypertension.

TRIAL REGISTRATION

Clinical trials registration number: NCT00971165.

Fine-needle aspiration biopsy versus core-needle biopsy in diagnosing lung cancer: a systematic review

BACKGROUND

Lung cancer leads cancer-related mortality in the world. The objective of the present systematic review was to compare fine-needle aspiration biopsy (fnab) with core-needle biopsy (cnb) for diagnostic characteristics and yields for diagnosing lung cancer in patients with lung lesions.

METHODS

The medline and embase databases (from January 1, 1990, to September 14, 2009), the Cochrane Library (to Issue 4, 2009), and selected guideline Web sites were searched for relevant articles.

RESULTS

For overall diagnostic characteristics (benign vs. malignant) of fnab and cnb, the ranges of sensitivity were 81.3%-90.8% and 85.7-97.4% respectively; of specificity, 75.4%-100.0% and 88.6%-100.0%; and of accuracy, 79.7%-91.8% and 89.0%-96.9%. For specific diagnostic characteristics of fnab and cnb (identifying the histologic subtype of malignancies or the specific benign diagnoses), the ranges of sensitivity were 56.3%-86.5% and 56.5-88.7% respectively; of specificity, 6.7%-57.1% and 52.4%-100.0%; and of accuracy, 40.4%-81.2% and 66.7%-93.2%. Compared with fnab, cnb did not result in a higher complication rate (pneumothorax or hemoptysis). No study has yet compared the diagnostic yields of fnab and of cnb for molecular predictive-marker studies in patients with lung lesions.

DISCUSSION AND CONCLUSIONS

The evidence is currently insufficient to support a difference between fnab and cnb in identifying lung malignancies in patients with lung lesions. Compared with fnab, cnb might have a higher specificity to diagnose specific benign lesions. Well-designed, good-quality studies comparing fnab with cnb for diagnostic characteristics and yields in diagnosing lung cancer should be encouraged.

The radiological spectrum of pulmonary lymphoproliferative disease

Pulmonary lymphoproliferative disorders (LPD) are characterised by abnormal proliferation of indigenous cell lines or infiltration of lung parenchyma by lymphoid cells. They encompass a wide spectrum of focal or diffuse abnormalities, which may be classified as reactive or neoplastic on the basis of cellular morphology and clonality. The spectrum of reactive disorders results primarily from antigenic stimulation of bronchial mucosa-associated lymphoid tissue (MALT) and comprises three main entities: follicular bronchiolitis, lymphoid interstitial pneumonia and (more rarely) nodular lymphoid hyperplasia. Primary parenchymal neoplasms are most commonly extranodal marginal zone lymphomas of MALT origin (MALT lymphomas), followed by diffuse large B-cell lymphomas (DLBCLs) and lymphomatoid granulomatosis (LYG). Secondary lymphomatous parenchymal neoplasms (both Hodgkin and non-Hodgkin lymphomas) are far more prevalent than primary neoplasms. Acquired immune deficiency syndrome (AIDS)-related lymphoma (ARL) and post-transplantation lymphoproliferative disorder (PTLD) may also primarily affect the lung parenchyma. Modern advances in treatments for AIDS and transplant medicine are associated with an increase in the incidence of LPD and have heightened the need to understand the range of imaging appearance of these diseases. The multidetector CT (MDCT) findings of LPD are heterogeneous, thereby reflecting the wide spectrum of clinical manifestations of these entities. Understanding the spectrum of LPD and the various imaging manifestations is crucial because the radiologist is often the first one to suggest the diagnosis and has a pivotal role in differentiating these diseases. The current concepts of LPD are discussed together with a demonstration of the breadth of MDCT patterns within this disease spectrum.

Influence of different types of seat cushions on the static sitting posture in individuals with spinal cord injury

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To evaluate the efficacy of the Postural Assessment Software PAS/SAPO in the posture analysis of individuals with spinal cord injury (SCI) during sitting position and to analyze if the use of different types of seat cushions-gel and foam, with no cushion-can interfere in the individual's posture during sitting position.

SETTING

Centre of Rehabilitation at the University Hospital (FMRP-USP), Ribeirão Preto, Brazil.

METHODS

Eight individuals, four paraplegics and four tetraplegics with SCI and 20 healthy individuals participated in the study. Photos were taken of individuals in the sitting position using foam, gel cushions and with no cushion. They were analyzed using the PAS/SAPO. The alignment of the anterior-superior iliac spine (ASIS) and the posterior pelvic tilt were evaluated from the angle formed between the ASIS and the greater trochanter of the femur.

RESULTS

The group of healthy individuals presented the best postural alignment when compared with the group with SCI, both for the ASIS alignment (P<0.05) and for the degree of posterior pelvic tilt (P<0.05). No significant differences were found in the variables analyzed when the seat cushions were compared.

CONCLUSION

The different types of cushions did not alter the sitting posture; however, individuals with SCI showed worse postural alignment than the healthy individuals. PAS/SAPO was demonstrated to be useful for postural assessment.

Clinical depression and HIV risk-related sexual behaviors among African-American adolescent females: unmasking the numbers

Clinically depressed and nondepressed African-American adolescent females aged 13-19 years (N=131) were interviewed and surveyed to determine the relationship between depression and HIV risk-related sexual behaviors. Narratives indicate that the psychopathology of depression may create situations where the target population could become exposed to HIV. Specifically, depressed participants described feelings of loneliness, isolation, and wanting somebody to "comfort them" as aspects of depression that affect the decisions they make about sex and relationships. In essence, sex was viewed as a stress reliever, an anti-depressant and a way to increase self-esteem. They shared that even if they did not feel like having sex, they might just "git it over wit" so their partners would stop asking. Some also discussed financial and emotional stability offered by older, more sexually experienced partners. These age-discordant relationships often translated into trusting that their partners knew what was best for their sexual relationships (i.e., having unprotected sex). Sixty-nine percent (n=88) of the sample reported engaging in sexual activity. Given their mean age (16 ± 1.9 years) participants had been sexually active for 2 ± 1.8 years. The adolescents reported an average of 2 ± 1.8 sexual partners within the past three months. Depressed participants reported a higher frequency of having ever had sex (78% vs. 59%, χ(2)=5.236, p=0.022), and had a higher mean number of sexual partners (2 vs. 1, t=-2.023, p= 0.048) and sexual encounters under the influence of drugs and alcohol (8 vs. 2, t=-3.078, p=0.005) in the past three months. The results of this study can guide the modification and/or development of tailored HIV/sexually transmitted infection (STI) prevention programs. The findings provide explicit, psychologically and culturally relevant information regarding the interaction between depression, self-medicating behaviors and risk for HIV/STIs among clinically depressed African-American adolescent females.

The association between osteoporosis and static balance in elderly women

SUMMARY

This study aimed at answering the question: do people with high bone loss have greater postural instability? Groups were separated into group 1: women with normal bone mineral density, group 2: women with osteopenia, and group 3: women with osteoporosis. The balance was evaluated in four upright postural situations. Osteoporosis group had greater oscillation in the anteroposterior displacement in all situations compared to control group and the greatest mediolateral displacement in all situations compared to other groups.

INTRODUCTION

It is not known whether the presence of osteoporosis can be considered a factor aggravating the postural control. This study aimed at answering the question: do people with high bone loss have greater postural instability?

METHODS

This study was divided into three groups: group 1 (n = 20) consisting of women with normal bone mineral density, group 2 (n = 20) women with osteopenia, and group 3 (n = 20) women with osteoporosis. All the participants were submitted to evaluation of the balance using the Polhemus system in four upright postural situations.

RESULTS

Osteoporosis group had greater oscillation in the anteroposterior displacement in all situations compared to control group. The osteoporosis group also showed the greatest mediolateral displacement in all situations compared to other groups.

CONCLUSION

The results suggest that osteoporotic women had the worst balance, possibly due to the more pronounced body changes compared to non-osteoporotic women.

A concept analysis of relational aggression

The purpose of this article is to conduct a concept analysis of the phenomenon of relational aggression. With the increases in violence among our youth, the topic of aggression, and more specifically relational aggression, has gained an increasing interest. Discussion of relational aggression is imperative because it lends credence to a type of aggression not readily studied in previous decades. A new understanding of relational aggression will aide in future nursing and multidisciplinary research studies and will guide health promotion interventions to alleviate the consequences of relational aggression for adolescent girls. Therefore, with an increased knowledge about the consequences of relational aggression the nurse can provide appropriate nursing interventions to combat the detriment associated with it.

Collagen and elastic system in the remodelling process of major types of idiopathic interstitial pneumonias (IIP)

AIMS

Structural remodelling in acute and chronic idiopathic interstitial pneumonia (IIP) has been extensively investigated, but little attention has been directed to the elastic tissue in these situations. The aim of this study was to determine whether elastic deposition accompanies collagen deposition in the four major histological patterns of IIP: diffuse alveolar damage (DAD), organizing pneumonia (OP), non-specific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP).

METHODS AND RESULTS

We measured, by image analysis, the content of fibres of the collagenous and elastic systems of the alveolar septum in histological slides of open lung biopsies, using the picrosirius-polarization method and Weigert's resorcin-fuchsin stain, respectively. Five groups were studied: 10 cases of DAD; nine cases of OP; nine cases of NSIP; and 10 cases of UIP. Four normal lungs were used for comparison. The content of collagen fibres was significantly higher in UIP when compared to DAD, NSIP, OP and normal lung. The content of elastic fibres was increased in comparison with normal lungs but this was not significantly different among the histological patterns.

CONCLUSION

Acute and chronic IIP cause a similar increase in the collagen and elastic contents of the lungs, representing a process of 'fibroelastosis' rather than an exclusive process of fibrosis. A profibrogenic mechanism is responsible for the unparallelled collagen augmentation observed in UIP subjects, the nature of which is yet to be determined.

Collagen and elastic system in the remodelling process of major types of idiopathic interstitial pneumonias (IIP)

AIMS

Structural remodelling in acute and chronic idiopathic interstitial pneumonia (IIP) has been extensively investigated, but little attention has been directed to the elastic tissue in these situations. The aim of this study was to determine whether elastic deposition accompanies collagen deposition in the four major histological patterns of IIP: diffuse alveolar damage (DAD), organizing pneumonia (OP), non-specific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP).

METHODS AND RESULTS

We measured, by image analysis, the content of fibres of the collagenous and elastic systems of the alveolar septum in histological slides of open lung biopsies, using the picrosirius-polarization method and Weigert's resorcin-fuchsin stain, respectively. Five groups were studied: 10 cases of DAD; nine cases of OP; nine cases of NSIP; and 10 cases of UIP. Four normal lungs were used for comparison. The content of collagen fibres was significantly higher in UIP when compared to DAD, NSIP, OP and normal lung. The content of elastic fibres was increased in comparison with normal lungs but this was not significantly different among the histological patterns.

CONCLUSION

Acute and chronic IIP cause a similar increase in the collagen and elastic contents of the lungs, representing a process of 'fibroelastosis' rather than an exclusive process of fibrosis. A profibrogenic mechanism is responsible for the unparallelled collagen augmentation observed in UIP subjects, the nature of which is yet to be determined.

Intrapericardial paraganglioma

We describe the case of an intrapericardial pheochromocytoma located in the anterior surface of the heart and spreading over the pulmonary trunk. Under cardiopulmonary bypass (CPB) the tumor was removed. "En bloc" resection of the anterior wall of the right ventricular infundibulum and the pulmonary trunk was performed, with implantation of a fresh aortic homograft in the pulmonary position to avoid free pulmonary regurgitation.

[Subacute sclerosing panencephalitis: correlation between immunologic and histopathologic aspect]

Foi realizado um estudo clínico, laboratorial, eletroencefalográfico, sorológico e virológico em 4 pacientes com o diagnóstico clínico de "panencefalite subaguda esclerosante". Em todos constatou-se uma elevada concentração de anticorpos contra sarampo, tanto no líquido céfalo-raquidiano como no soro sangüíneo, sendo que em 3 pacientes a concentração de anticorpos era mais elevada no líquido céfalo-raquidiano. Em dois destes pacientes foram feitas biópsias cerebrais, que evidenciaram um processo meningo-encefalítico crônico, com focos de neuroniofagia esparsos e infiltrados inflamatórios perivasculares de natureza linfoplasmocitária. Ao mesmo tempo fez-se uma revisão de 18 casos desta enfermidade, já publicados, agora no sentido de estudar mais detidamente a natureza da infiltração inflamatória meníngea e perivascular. O aspecto histopatológico resumia-se em infiltração linfoplasmocitária meníngea esparsa, contrastando com densos infiltrados inflamatórios perivasculares também linfoplasmocitários, muitas vezes com grande riqueza em "corpos de Russell". Em vista destes achados sugere-se a possibilidade de que os anticorpos contra sarampo, encontrados em elevada concentração no líquido céfalo-raquidiano destes pacientes, sejam produzidos nos infiltrados perivasculares do próprio tecido nervoso.

Double-outlet right ventricle with pulmonic stenosis. Surgical considerations and results of operation

The results of complete repair of double-outlet right ventricle with pulmonic stenosis in 22 Mayo Clinic patients were analyzed. The overall mortality rate was 32%. Since 1960, the mortality rate has been reduced to 16%. Anomalies of the distribution of the right coronary artery, a second ventricular septal defect of the atrioventricular canal type, and significant residual pulmonic stenosis were associated with a higher mortality rate. The difficulties in the diagnosis of this uncommon condition are emphasized.

Complete repair is best carried out after the patient is 4 years old. A systemic-to-pulmonary arterial shunt is the procedure of choice for those who are younger than this. In the occasional patient with anomalous distribution of the right coronary artery which precludes adequate relief of the pulmonic stenosis, use of an aortic homograft from the right ventricle to the pulmonary artery should be considered.

Double-outlet right ventricle without pulmonic stenosis. Surgical considerations and results of operation

The results of complete repair of double-outlet right ventricle without pulmonic stenosis in 18 Mayo Clinic patients are analyzed; the over-all operative mortality rate was 22%. Pulmonary vascular obstructive disease and a second ventricular septal defect of the atrioventricular canal type were associated with a higher mortality rate. The difficulties in the diagnosis of this uncommon condition are emphasized.

Patients with double-outlet right ventricle without pulmonic stenosis should have complete repair early in life before the onset of severe pulmonary vascular obstructive disease-the only specific contraindication to operation. Pulmonary artery banding may be preferable as a first-stage palliative procedure in infants less than six months old who do not respond to medical therapy.