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ABSTRACT The rate of visual field progression is an essential factor in determining risk of visual disability or blindness in glaucoma patients. Knowledge of the rate of progression of a particular patient, in combination with an estimation of their longevity and other clinical factors, allows clinicians to optimize management by providing appropriately aggressive treatment. Despite decades of research on the treatment of glaucoma, the natural history of glaucomatous visual field progression in untreated and treated patients remains unclear. The purpose of this review is to provide a comprehensive summary of the literature surrounding the rate of visual field progression in glaucoma. Most of the available data pertains to primary open angle glaucoma, but we will also review progression rates in other subtypes of open angle glaucoma, such as pseudoexfoliative glaucoma and normal tension glaucoma, as well as in primary angle closure glaucoma. Specifically, we will cover methods to identify rates of progression, rates of progression in treated versus untreated patients, factors that may influence progression, and lastly, suggest some parameters that might help clinicians in determining acceptable rates of visual field deterioration in patients with glaucoma.

RESUMO A taxa de progressão do campo visual é um fator essencial para determinar o risco de incapacidade visual ou cegueira em pacientes com glaucoma. Conhecer a taxa de progressão de um determinado paciente, em combinação com uma estimativa de sua longevidade e outros fatores clínicos, permite que os médicos otimizem a conduta, fornecendo um tratamento adequadamente agressivo. Apesar de décadas de pesquisa sobre o tratamento do glaucoma, a história natural da progressão do campo visual glaucomatoso em pacientes não tratados e tratados permanece pouco clara. O objetivo desta revisão é fornecer um resumo abrangente da literatura sobre a taxa de progressão do campo visual do glaucoma. A maioria dos dados disponíveis diz respeito ao glaucoma de ângulo aberto primário, mas também revisaremos as taxas de progressão em outros subtipos de glaucoma de ângulo aberto, como o glaucoma pseudoexfoliativo e o glaucoma de tensão normal, bem como o glaucoma primário de ângulo fechado. Especificamente, iremos cobrir métodos para identificar taxas de progressão, taxas de progressão em pacientes tratados versus não tratados, fatores que podem influenciar a progressão e, finalmente, sugerir alguns parâmetros que podem ajudar os médicos a determinar taxas aceitáveis de deterioração do campo visual em pacientes com glaucoma

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OBJECTIVES: Previous obesity prevention studies in preschool-age children have included non-Hispanic Black (NHB) children, but few have investigated between-subgroup differences even though there may be cultural risk and protective practice differences, challenging the generalizability of findings. The purpose of this study was to examine differences in early childhood obesity-related factors in NHB subgroups (Haitian, other Caribbean Islander and African-American [AA]) children. METHODS: Baseline data from two randomized controlled trials in 52 childcare centers of which 35 had data to test a preschool-based obesity prevention intervention was analyzed. The sub-sample included 370 caregiver-child dyads; 209 self-identified as AA, 120 as Haitian and 41 as Caribbean Islander/West Indian or mixed race. Multilevel regression models generated outcome estimates for group differences in body mass index (BMI) percentile, birthweight, breastfeeding initiation and duration, bottle feeding duration and age when solid foods were introduced. RESULTS: Mean BMI percentile was similar for AA, Haitian and Caribbean Islander/West Indian/Multiracial (60.1th percentile, 60.8th percentile, 62.8th percentile, respectively) as was birthweight (6.3, 6.8, and 6.6 lb, respectively). Children of US-born caregivers had significantly lower BMI percentiles (9.13 percentile points) versus foreign-born caregivers. Haitian women were significantly more likely to initiate breastfeeding (64.9%) versus AA (47.6%) and Caribbean Islander/West Indian/Multiracial (62.2%) (p < .01). No significant group differences were found in breastfeeding or bottle feeding duration or age solid foods were introduced. CONCLUSIONS: Findings here suggest that NHB race classification can identify important subgroup behavioral similarities which in turn may inform culturally sensitive strategies to promote early childhood healthy weight. Foreign-born caregivers may benefit from healthy weight promotion information, and as early as possible in their child's development.

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The aim of this study was to perform a literature review on the use of finite element modeling (FEM) for the evaluation of the biomechanical behavior of temporomandibular joint replacement (TMJR) devices. An electronic search of online medical and scientific literature database was conducted using selected search terms. The search identified 307 studies, of which 19 were considered relevant to this study. Of the 19 selected studies, 10 (52.6%) investigated the influence of geometry and fixation methods, while two (10.5%) evaluated the behavior of artificial condyle-fossa structures. The TMJR devices assessed in these studies included TMJ Inc. (aka Christensen; 63.2%), Zimmer Biomet (15.7%), Stryker (10.5%), and a theoretical intramedullary condylar component (5.3%); 26.3% of the studies evaluated custom TMJR devices. Such studies provided important data on the distribution of strain and stress through TMJR structural components and surrounding bone by using different software systems and methods. The mean stress values were lower on a custom TMJR condyle-ramus component and the supporting bone than on the stock device. FEM proved to be an accurate and valuable biomechanical simulation tool for studying the current TMJR devices and should be considered a useful tool for the improvement and development of future joint replacement devices.

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This study aimed to assess the literature available on the effects, on peri-implant tissues, of degradation products released from dental implants as a consequence of therapeutic treatment for peri-implantitis and/or of wear-corrosion of titanium. A literature review of the PubMed medline database was performed up to December 31, 2016. The following search terms were used: "titanium wear and dental implant"; "titanium corrosion and dental implant"; "bio-tribocorrosion"; "peri-implantitis"; "treatment of peri-implantitis"; "titanium particles release and dental implant"; and "titanium ion release and dental implant". The keywords were applied to the database in different combinations without limits of time period or type of work. In addition, the reference lists of relevant articles were searched for further studies. Seventy-nine relevant scientific articles on the topic were retrieved. The results showed that pro-inflammatory cytokines, infiltration of inflammatory response cells and activation of the osteoclasts activity are stimulated in peri-implant tissues in the presence of metal particles and ions. Moreover, degenerative changes were reported in macrophages and neutrophils that phagocytosed titanium microparticles, and mutations occurred in human cells cultured in medium containing titanium-based nanoparticles. Debris released from the degradation of dental implants has cytotoxic and genotoxic potential for peri-implant tissues. Thus, the amount and physicochemical properties of the degradation products determine the magnitude of the detrimental effect on peri-implant tissues.

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Two-piece implant systems are mainly used in oral implantology involving an osseointegrated implant connected to an abutment, which supports prosthetic structures. It is well documented that the presence of microgaps, biofilms and oral fluids at the implant-abutment connection can cause mechanical and biological complications. The aim of this review paper was to report the degradation at the implant-abutment connection by wear and corrosion processes taking place in the oral cavity. Most of the retrieved studies evaluated the wear and corrosion (tribocorrosion) of titanium-based materials used for implants and abutments in artificial saliva. Electrochemical and wear tests together with microscopic techniques were applied to validate the tribocorrosion behavior of the surfaces. A few studies inspected the wear on the inner surfaces of the implant connection as a result of fatigue or removal of abutments. The studies reported increased microgaps after fatigue tests. In addition, data suggest that micromovements occurring at the contacting surfaces can increase the wear of the inner surfaces of the connection. Biofilms and/or glycoproteins act as lubricants, although they can also amplify the corrosion of the surfaces. Consequently, loosening of the implant-abutment connection can take place during mastication. In addition, wear and corrosion debris such as ions and micro- and nanoparticles released into the surrounding tissues can stimulate peri-implant inflammation that can lead to pathologic bone resorption.

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UNLABELLED: Lipopolysaccharide (LPS) may induce peri-implantitis and implant failure. However, the role of LPS in titanium (Ti) electrochemical behavior remains unknown. We hypothesized that LPS in saliva with different pHs affects Ti corrosion properties. Thirty-six Ti discs (15 mm × 3 mm) were divided into 12 groups according to saliva pH (3, 6.5, and 9) and Escherichia coli LPS concentration (0, 0.15, 15, and 150 µg/mL). Electrochemical tests, such as open circuit potential, potentiodynamic, and electrochemical impedance spectroscopy, were conducted in a controlled environment. Data were evaluated by Pearson correlation and regression analysis (α = 0.05). LPS and pH affected Ti corrosive behavior. In general, lower pH and higher LPS concentration accelerated Ti corrosion. In the control group, the increase of pH significantly reduced the corrosion rate and increased the capacitance of the double layer. In LPS groups, the decrease of pH significantly increased the corrosion rate of Ti. LPS negatively influenced Ti corrosion behavior. ABBREVIATIONS: C(dl), capacitance of double layer; E(corr), corrosion potential; EIS, electrochemical impedance spectroscopy; I(corr), corrosion current density; I(pass), passivation current density; LPS, lipopolysaccharide; OCP, open circuit potential; R(p), polarization resistance; Ti, titanium.

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Carbon nanotubes are highly versatile materials; new applications using them are continuously being developed. Special attention is being dedicated to the possible use of multiwalled carbon nanotubes in biomaterials contacting with bone. However, carbon nanotubes are also controversial in regards to effects exerted on living organisms. Carbon nanotubes can be used to improve the tribological properties of polymer/composite materials. Ultrahigh molecular weight polyethylene (UHMWPE) is a polymer widely used in orthopedic applications that imply wear and particle generation. We describe here the response of human osteoblast-like MG63 cells after 6 days of culture in contact with artificially generated particles from both UHMWPE polymer and multiwalled carbon nanotubes (MWCNT)/UHMWPE nanocomposites. This novel composite has superior wear behavior, having thus the potential to reduce the number of revision hip arthroplasty surgeries required by wear failure of acetabular cups and diminish particle-induced osteolysis. The results of an in vitro study of viability and proliferation and interleukin-6 (IL-6) production suggest good cytocompatibility, similar to that of conventional UHMWPE (WST-1 assay results are reported as percentage of control +/- SD: UHMWPE = 96.19 +/- 7.92, MWCNT/UHMWPE = 97.92 +/- 8.29%; total protein: control = 139.73 +/- 10.78, UHMWPE = 137.07 +/- 6.17, MWCNT/UHMWPE = 163.29 +/- 11.81 microg/mL; IL-6: control = 90.93 +/- 10.30, UHMWPE = 92.52 +/- 11.02, MWCNT/UHMWPE = 108.99 +/- 9.90 pg/mL). Standard cell culture conditions were considered as control. These results, especially the absence of significant elevation in the osteolysis inductor IL-6 values, reinforce the potential of this superior wear-resistant composite for future orthopedic applications, when compared to traditional UHMWPE.

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Carbon nanotubes are highly versatile materials; new applications using them are continuously being developed. Special attention is being dedicated to the possible use of multiwalled carbon nanotubes in biomaterials contacting with bone. However, carbon nanotubes are also controversial in regards to effects exerted on living organisms. Carbon nanotubes can be used to improve the tribological properties of polymer/composite materials. Ultrahigh molecular weight polyethylene (UHMWPE) is a polymer widely used in orthopedic applications that imply wear and particle generation. We describe here the response of human osteoblast-like MG63 cells after 6 days of culture in contact with artificially generated particles from both UHMWPE polymer and multiwalled carbon nanotubes (MWCNT)/UHMWPE nanocomposites. This novel composite has superior wear behavior, having thus the potential to reduce the number of revision hip arthroplasty surgeries required by wear failure of acetabular cups and diminish particle-induced osteolysis. The results of an in vitro study of viability and proliferation and interleukin-6 (IL-6) production suggest good cytocompatibility, similar to that of conventional UHMWPE (WST-1 assay results are reported as percentage of control ± SD: UHMWPE = 96.19 ± 7.92, MWCNT/UHMWPE = 97.92 ± 8.29 percent; total protein: control = 139.73 ± 10.78, UHMWPE = 137.07 ± 6.17, MWCNT/UHMWPE = 163.29 ± 11.81 µg/mL; IL-6: control = 90.93 ± 10.30, UHMWPE = 92.52 ± 11.02, MWCNT/UHMWPE = 108.99 ± 9.90 pg/mL). Standard cell culture conditions were considered as control. These results, especially the absence of significant elevation in the osteolysis inductor IL-6 values, reinforce the potential of this superior wear-resistant composite for future orthopedic applications, when compared to traditional UHMWPE.

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A peptide toxin was isolated from the venom of Palamneus gravimanus, the Indian black scorpion, to block human Kv1.1 channels expressed in Xenopus laevis oocytes. A 4.5 kD peptide (toxin), as confirmed by SDS-PAGE, was purified to homogeneity by ion exchange chromatography using CM-Sephadex C-25 followed by Sephadex G-50 gel filtration. Palamneus gravimanus toxin (PGT) selectively blocks the human cloned voltage-gated potassium channel hKv1.1 in a two-electrode voltage-clamp (TEVC) technique. The results obtained indicate that the toxin blocks the hKv1.1 channel at a nanomolar concentration range (Ki value of 10 nM) of the peptide to the external side of the cell. The blockage seems to be voltage-dependent. Comparative structure of PGT (a 4.5 kD peptide) with BTK-2 suggests a close relationship; therefore this toxin can be employed to investigate the hKv1.1 channel structure.

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A peptide toxin was isolated from the venom of Palamneus gravimanus, the Indian black scorpion, to block human Kv1.1 channels expressed in Xenopus laevis oocytes. A 4.5 kD peptide (toxin), as confirmed by SDS-PAGE, was purified to homogeneity by ion exchange chromatography using CM-Sephadex C-25 followed by Sephadex G-50 gel filtration. Palamneus gravimanus toxin (PGT) selectively blocks the human cloned voltage-gated potassium channel hKv1.1 in a two-electrode voltage-clamp (TEVC) technique. The results obtained indicate that the toxin blocks the hKv1.1 channel at a nanomolar concentration range (Ki value of 10 nM) of the peptide to the external side of the cell. The blockage seems to be voltage-dependent. Comparative structure of PGT (a 4.5 kD peptide) with BTK-2 suggests a close relationship; therefore this toxin can be employed to investigate the hKv1.1 channel structure.

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Since Mycobacterium leprae are rarely demonstrable in the tuberculoid spectrum of leprosy, a confirmatory diagnosis of leprosy can be made on the basis of finding active destruction of cutaneous nerves by granulomatous inflammation in a skin biopsy. Immunoperoxidase staining for S-100 protein, which is a marker for Schwann cells, was used to delineate nerves in lesional skin biopsies of 25 patients with tuberculoid and borderline tuberculoid leprosy as well as 15 controls with nonleprous granulomatous inflammation. Four different patterns of nerve damage were observed: infiltrated, fragmented, absent, and intact. All of the nonleprous granulomatous dermatoses showed only intact nerves, either inside or outside the granuloma, and so S-100 staining can be used to rule out leprosy.

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Se presenta un método sencillo para determinar la edad gestacional de los recién nacidos, basado solamente en cuatro características: la cápsula vascular anterior del cristalino, los surcos de la planta de los pies, el nódulo mamario y la firmeza del papellón auricular. La valoración crítica realizada mediante adecuados análisis estadísticos, demostró que se trata de un método útil de gran valor práctico, presentando unos límites de confianza del 95% correspondiente a 11 días. Dicho método es aplicable a todos los recién nacidos, incluso patológicos, en cualquier momento de los primeros 2 días de vida

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Renal involvement in 13 non-lepromatous and 17 lepromatous leprosy patients were assessed by routine urinalysis, detailed biochemical analysis of blood and urine and by renal histopathological studies and compared with 10 normal healthy controls. The presence of RBC and pus cells were detected in the urinary deposit of only one lepromatous leprosy patient in reactional phase. A reversal of albumin/globulin ratio was observed in 17.6% of non-lepromatous and 15.3% of lepromatous patients. 24 hours urinary excretion of sodium, potassium, chloride and aminonitrogen of the patients were within the normal range. Forth seven percent of the non-lepromatous and 46% of the lepromatous patients had proteinuria. Even though the mean serum creatinine values of the patients showed no difference from that of the normals, the creatinine clearance was low in 82.3% of the non-lepromatous and in all of the lepromatous patients. Serum phosphorus, serum uric acid, urinary phosphate excretion and the renal tubular reabsorption of phosphorus of the patients were normal. Twenty one percutaneous renal biopsy specimens showed nonspecific pathological changes such as nephritis of various varieties in 71.4% of the specimens. Among the lepromatous group renal involvement was observed in 5 out of 9 cases (55.6%) and in the non-lepromatous group 10 out of 12 cases (83.3%). No acid fast bacilli, amyloid and granuloma were seen in any of the renal tissues studied. There was no definite correlation between the type of renal pathology and biochemical changes. None of the patient showed any clinical evidence of renal involvement.

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