Echinococcus granulosus sensu stricto, Echinococcus ortleppi; and E. intermedius (G7) are present in Bolivia.

Cystic echinococcosis (CE) is a zoonotic disease caused by a complex of species known as Echinococcus granulosus sensu lato. CE is endemic in Argentina, Chile, Peru, Uruguay and the South part of Brazil. In contrast, little is known regarding the presence of CE in Bolivia. In this study, 35 cysts isolated from livestock (mostly from the Department of La Paz) and 3 from humans (La Paz, Oruro and Potosi) were genetically characterized analysing the sequence of the cox1 gene (1609 bp). In total, 30 cysts (from La Paz, Cochabamba and Beni) were characterized as E. granulosus sensu stricto (3 fertile and 4 non-fertile cysts from sheep, 8 fertile and 12 non-fertile cysts from cattle and 3 fertile cysts from humans). A detailed analysis of the cox1 haplotypes of E. granulosus s.s. is included. Echinococcus ortleppi (G5) was found in 5 fertile cysts from cattle (from La Paz and Cochabamba). Echinococcus intermedius (G7) was identified in 3 fertile cysts from pigs (from Santa Cruz). Additionally, E. granulosus s.s. was detected in 4 dog faecal samples, while E. ortleppi was present in other two dog faecal samples. The implications of these preliminary results in the future implementation of control measures are discussed.

The contribution of histopathological examination to the diagnosis of cervico-facial actinomycosis: a retrospective analysis of 68 cases.

Cervico-facial actinomycosis is an infectious, suppurative, and granulomatous disease due to Actinomyces species. Usually, the diagnosis is confirmed by microbiological cultures; however, the need for careful anaerobic handling of specimens often makes it difficult to obtain an effective microbial growth. Therefore, we conducted a retrospective study on biopsy samples from patients with a clinical suspicion of cervico-facial actinomycosis, in order to determine whether accurate histopathological examination could reliably confirm the diagnosis. A retrospective revision of formalin-fixed, paraffin-embedded archival material from 68 cases of cervico-facial lesions, with negative culture for anaerobic/microaerophilic microorganisms, was performed. Twelve serial sections for each case were cut from the paraffin blocks, individually collected on positively charged slides to obtain good section-to-slide adhesion, and stained with hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS). Histopathological examination of the serial sections allowed the identification of bacterial colonies consistent with actinomycetes in 22 cases (32 %). The proposed histopathological examination allowed the retrospective diagnosis of cervical actinomycosis in one-third of clinical specimens that remained misdiagnosed following traditional H&E examination.

Pre-clinical evaluation of a new coral-based bone scaffold.

Coral is used worldwide for bone reconstruction. The favorable characteristics that make this material desirable for implantation are (i) osteoinduction, (ii) and osteoconduction. These proprieties have been demonstrated by in vivo studies with animal models and clinical trials over a twenty-year period. Also poly(2-hydroxyethylmethacrylate) [poly(HEMA)] is a widely used biomaterial. By using coral and poly(HEMA), a scaffold for bone reconstruction application has been recently synthesized. Cytological, histological and genetic analyses were performed to characterize this new alloplastic material. Four samples were analyzed: (a) white coral (WC), (b) red coral (RC), (c) WC plus polymer (WCP) and (d) RC plus polymer (RCP). Quantification of mitochondrial dehydrogenase activity by MTT assay was performed as indirect detector of cytotoxicity. In vivo effects were revealed by implanting corals and coral-based polymers in rabbit tibia. Samples were collected after 4 weeks and subjected to histological analysis. To evaluate the genetic response of cells to corals and coral-derived polymers an osteoblastlike cell line (i.e. MG63) was cultured in wells containing (a) medium, (b) medium plus corals and (c) medium plus two types of scaffolds (RCP or WCP). RNAs extracted from cells were retro-transcribed and hybridized on DNA 19.2K microarrays. No cytotoxicity was detected in corals and coral-based biopolymers. No inflammation or adverse effect was revealed by histological examination. By microarray analysis 154 clones were differentially expressed between RC and WC (81 up and 73 down regulated) whereas only 15 clones were repressed by the polymer. Histological evaluation not only confirmed that coral is a biocompatible material, but also that the polymer has no adverse effect. Microarray results were in agreement with cytological and histological analyses and provided further data regarding the genetic effects of RC, WC and the new polymer.

Expression of poly(ADP-ribose) polymerase in bone regeneration.

Poly(ADP-ribose) polymerase (PARP) is a 116kDa enzyme catalysing the synthesis of ADP-ribose polymers from NAD+. PARP is activated in response to DNA strand breaks and plays a critical role in the maintenance of genomic integrity. However, considering its role also in transcription, proliferation as well as apoptosis in biological process, in the present study the role of PARP in bone regeneration was evaluated, in particular in bone cell proliferation and differentiation processes. Thus, formalin fixed paraffin embedded specimens of 10 human bone samples after sinus lift were collected and investigated by immunohistochemistry using a mouse monoclonal anti-human PARP antibody. PARP was expressed in cells with morphological features of osteoblasts in the areas of new bone formation at the junction between mineralized and unmineralized tissue, between osteoid tissue and bone. Few osteoclasts were observed and showed only focal nuclear expression of PARP, while osteocytes showed no positivity for PARP. Our data showed an overall involvement of PARP enzyme in human bone tissues, in particular during bone regeneration process.

Bioactive properties of Persea lingue Ness (Lauraceae) fruit and leaf extracts.

Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.

Early steroid withdrawal in pediatric renal transplantation at a single center: preliminary report.

Steroids have been a cornerstone in renal transplant immunosuppression despite cardiovascular risk and growth impairment in children. New immunosuppressive drugs have allowed early withdrawal or even complete avoidance of steroids. To evaluate a new immunosuppressive protocol with early withdrawal of steroids in a pediatric renal transplant population, we initiated a prospective study in recipients >1 year old who showed low immunologic risk was started. Group A (n = 12) received decreasing doses of steroids until day posttransplant 7 under a regimen of Tacrolimus (FK) and mycophenolate mofetil (MMF). Group B (n = 11) were controls treated with steroids, cyclosporine and azathioprine. In both groups, induction therapy included basiliximab. We evaluated anthropometric and biochemical variables, acute rejection episodes (ARE), and cytomegalovirus (CMV) infection. Mean values and variations for continuous variables were calculated at months 1 and 3 for comparison at the same time using student's t-test and regresion analysis. We obtained mean values at months 1, 3, and 6 for groups A and B of creatinine clearance (mL/min): 86.2 versus 107.4; 76.9 versus 96.6; 73.3 versus 97.9 (P < .05); hematocrit (%) was 27.4 versus 31.8; 29.3 versus 33.9; 32.9 versus 34.3% (P < .05); total cholesterol (mg/dL), 148 versus 195, 139 versus 85, 142 versus 174 (P < .05); creatinine clearance decreased in both groups during follow-up with a smaller slope among group A (P < .05). No differences were observed between the groups in Z height, diastolic and systolic blood pressures at 6 months of follow-up. Serum total cholesterol mean levels at months 1, 3, and 6 were significantly lower among the group withdrawn from steroids (P < .05). Plasma bicarbonate levels were lower among group A than B; there was no difference in blood glucose levels. No AREs and no difference in CMV infections were observed. In conclusion, early withdrawal of steroids with FK and MMF was not associated with a higher incidence of either ARE or CMV infection. Lower levels of cholesterol could imply a reduced cardiovascular risk. Longer follow-up is needed to evaluate the impact of this therapy on renal function and linear growth.

Bioactive properties of Persea lingue Ness (Lauraceae) fruit and leaf extracts / Propriedades bioativas de extratos de folhas e frutos de Persea lingue Ness (Lauraceae)

Abstract Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.

Resumo Persea lingue Ness é uma árvore que vive principalmente na floresta temperada do centro-sul do Chile. As folhas são usadas na etnomedicina. O fruto é uma drupa similar ao abacate e que nunca foi pesquisada anteriormente. O objetivo deste estudo foi o de avaliar a citotoxicidade em células leucêmicas e as atividades antibacterianas, assim como algumas características químicas do extrato de fruto e da folha do P. lingue. As atividades antibacterianas foram determinadas pelo método da inibição do crescimento bacteriano em meio líquido empregando-se bactérias Gram-positivas e Gram-negativas. As linhagens celulares leucêmicas, Kasumi-1 e Jurkat foram usadas para avaliar a atividade citotóxica em ensaios empregando-se iodeto de propídio e AlamarBlue. Foram avaliados os teores totais de fenóis, flavonóides, taninos condensados, alcalóides e lipídeos presentes nos extratos das folhas e dos frutos. As atividades antioxidantes de ambos os extratos também foram avaliadas. O extrato das folhas foi o que apresentou o maior conteúdo de fenóis, taninos condensados e flavonóides totais e a maior atividade antioxidante. Já o extrato de fruto apresentou a maior quantidade de lipídios e alcaloides e a melhor atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium e Micrococcus luteus. Já o extrato das folhas apresentou apenas atividade contra M. luteus. Em relação à atividade citotóxica, apenas o extrato do fruto apresentou citotoxicidade contra as linhagens celulares Jurkat e Kasumi-1. Em resumo, o extrato do fruto de P. lingue é uma potencial fonte de moléculas com atividade biológica para o desenvolvimento de novos fármacos a serem utilizados em alguns tipos de leucemia, bem como agente antibacteriano.

Bioactive properties of Persea lingue Ness (Lauraceae) fruit and leaf extracts / Propriedades bioativas de extratos de folhas e frutos de Persea lingue Ness (Lauraceae)

Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.

Persea lingue Ness é uma árvore que vive principalmente na floresta temperada do centro-sul do Chile. As folhas são usadas na etnomedicina. O fruto é uma drupa similar ao abacate e que nunca foi pesquisada anteriormente. O objetivo deste estudo foi o de avaliar a citotoxicidade em células leucêmicas e as atividades antibacterianas, assim como algumas características químicas do extrato de fruto e da folha do P. lingue. As atividades antibacterianas foram determinadas pelo método da inibição do crescimento bacteriano em meio líquido empregando-se bactérias Gram-positivas e Gram-negativas. As linhagens celulares leucêmicas, Kasumi-1 e Jurkat foram usadas para avaliar a atividade citotóxica em ensaios empregando-se iodeto de propídio e AlamarBlue. Foram avaliados os teores totais de fenóis, flavonóides, taninos condensados, alcalóides e lipídeos presentes nos extratos das folhas e dos frutos. As atividades antioxidantes de ambos os extratos também foram avaliadas. O extrato das folhas foi o que apresentou o maior conteúdo de fenóis, taninos condensados e flavonóides totais e a maior atividade antioxidante. Já o extrato de fruto apresentou a maior quantidade de lipídios e alcaloides e a melhor atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium e Micrococcus luteus. Já o extrato das folhas apresentou apenas atividade contra M. luteus. Em relação à atividade citotóxica, apenas o extrato do fruto apresentou citotoxicidade contra as linhagens celulares Jurkat e Kasumi-1. Em resumo, o extrato do fruto de P. lingue é uma potencial fonte de moléculas com atividade biológica para o desenvolvimento de novos fármacos a serem utilizados em alguns tipos de leucemia, bem como agente antibacteriano.

Bioactive properties of Persea lingue Ness (Lauraceae) fruit and leaf extracts

Abstract Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.

Resumo Persea lingue Ness é uma árvore que vive principalmente na floresta temperada do centro-sul do Chile. As folhas são usadas na etnomedicina. O fruto é uma drupa similar ao abacate e que nunca foi pesquisada anteriormente. O objetivo deste estudo foi o de avaliar a citotoxicidade em células leucêmicas e as atividades antibacterianas, assim como algumas características químicas do extrato de fruto e da folha do P. lingue. As atividades antibacterianas foram determinadas pelo método da inibição do crescimento bacteriano em meio líquido empregando-se bactérias Gram-positivas e Gram-negativas. As linhagens celulares leucêmicas, Kasumi-1 e Jurkat foram usadas para avaliar a atividade citotóxica em ensaios empregando-se iodeto de propídio e AlamarBlue. Foram avaliados os teores totais de fenóis, flavonóides, taninos condensados, alcalóides e lipídeos presentes nos extratos das folhas e dos frutos. As atividades antioxidantes de ambos os extratos também foram avaliadas. O extrato das folhas foi o que apresentou o maior conteúdo de fenóis, taninos condensados e flavonóides totais e a maior atividade antioxidante. Já o extrato de fruto apresentou a maior quantidade de lipídios e alcaloides e a melhor atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium e Micrococcus luteus. Já o extrato das folhas apresentou apenas atividade contra M. luteus. Em relação à atividade citotóxica, apenas o extrato do fruto apresentou citotoxicidade contra as linhagens celulares Jurkat e Kasumi-1. Em resumo, o extrato do fruto de P. lingue é uma potencial fonte de moléculas com atividade biológica para o desenvolvimento de novos fármacos a serem utilizados em alguns tipos de leucemia, bem como agente antibacteriano.

Pérdidas hemáticas en UCI: Breve estudio descriptivo / Blood loss in ICU: Brief descriptive study

Background: Anaemia and transfusions are frequent in critically ill patients and there are avoidable causes such as routine laboratory tests. Patients and methods: Descriptive study during one continuous week including patients over 18-years old in a medical-surgical ICU. Results: 18 patients were included during a week in 12 beds in our unit, median age 62,5 years, 50% male. Median daily blood loss was 35ml, 45% in laboratory samples and 27% related to renal replacement therapy. 3 patients required 1 transfusion of red blood cells. Conclusions: There is a pattern of continuous blood loss in critically ill patients, primarily in routine laboratory tests. (AU)

Squamous cell carcinoma of the lower lip: FAS/FASL expression, lymphocyte subtypes and outcome.

Squamous cell carcinoma (SCC) of the lip is a relatively common malignancy of the head and neck region. Tumour thickness, grading and perineural invasion are significant prognostic indicators. However, there is still the need of new reliable biological markers able to predict the prognosis of the single cases with an unfavourable biological behaviour unpredictable by the classic clinical-pathological parameters. 32 cases of (SCC) of the lower lip were analysed for their clincopathologic features, and immunohistochemical expression of Fas/FasL in neoplastic cells and in inflammatory infiltrate. Moreover the density and phenotype of tumour-infiltrating lymphocytes (TIL) were analysed. The results were related with the follow-up of the patients ranging from 2 to 6 years. The cases with over-expression of Fas/FasL in neoplastic cells and Fas+ in T cells preferentially showed a more aggressive clinical behaviour (P<0.01). Moreover we found an alteration of the normal expression of CD4 and CD8 lymphocyte types in ten cases. This data suggest that the Fas/FasL pathway is involved in the close relation between neoplastic cells and T cells and so in the biological behaviour of these tumours.

Cephalometric evaluation of the upper airway in patients with complete dentures.

AIM: Obstructive sleep apnea syndrome (OSAS) is a disorder characterised by repeated obstructions of the upper airway, with consequent episodes of apnea and hypopnea during sleep, snoring, and daytime sleepiness. Recently, a role of edentulism in the occurrence or in the worsening of this disorder was suspected. The aim of the study was to assess, through a cephalometric analysis, if the removal of denture induces, and where, modifications that can favour the pharynx collapse. METHODS: A total of 27 subjects with complete or partial loss of teeth and with heavy loss of the vertical dimension, were examined. The patients were submitted to radiographs of the cranium in supine position, to simulate as much as possible the night condition, with the denture in intercuspal position (ICP), and in relaxed position both with denture (D-RP) and without it (edentule-relaxed position, E-RP). The radiographs were analysed through specific measures for OSA evaluating the parameters that could be modified by the denture. RESULTS: The pharyngeal airway space (PAS) decreases, at the level of uvula, from ICP (6.7 mm) to RP (5.3 mm) (P< 0.05). The distance between the base and the tip of the tongue significatively decreased both from ICP vs E-RP (7.35 mm vs 6.87 mm; P< 0.05), both from D-RP to E-RP (7.22 mm vs 6.87 mm; P< 0.005). CONCLUSIONS: From the data obtained from the cephalometric analysis it seems that wearing denture induces modifications in the position of the tongue, of the jaw and of the pharyngeal airway space that can favour the reduction of apnea episodes.

Premature lesions of the carotid vessels in HIV-1-infected patients treated with protease inhibitors.

OBJECTIVES: To evaluate the presence of premature atherosclerotic lesions of epiaortic vessels in HIV-1-infected protease inhibitor-(PI) treated patients compared with PI-naive patients and healthy individuals. DESIGN: One-hundred and two HIV-1-positive patients, including 55 treated with PI for at least 12 months and 47 either naive or treated with PI-sparing regimens, were subjected to epiaortic vessel ultrasonography. These data were compared with those obtained from 104 healthy individuals. METHODS: Intima characteristics, pulsation and resistance indexes, and minimal, peak and mean speed were evaluated using a colour power doppler. Atherosclerotic plaques were described. Independent risk factors and values for glycaemia, cholesterolaemia and triglyceridaemia were considered. Statistical analysis included the chi-square test, Mantel-Haenszel test, odds ratio and logistic regression analysis. RESULTS: Of the PI-treated patients, 29 out of 55 (52.7%) presented acquired lesions of the vascular wall at ultrasonography, whereas similar lesions were found in seven out of 47 (14.9%) PI-naive patients. Of the 104 healthy individuals, seven cases (6.7%) of intimal medial thickness were noted. A slightly significant correlation was found between carotid lesions and age, male sex and hypercholesterolaemia, whereas cigarette smoking, hypertriglyceridaemia and Centers for Disease Control and Prevention stage significantly increased the risk of vascular lesions (P= 0.022, P= 0.017 and P= 0.079 respectively). However, the highest significance regarded use of PI (P= 0.011). These results were confirmed by logistic regression analysis. CONCLUSIONS: These data demonstrate a higher than expected prevalence of premature carotid lesions in the PI-treated compared with PI-naive patients. If confirmed, a periodic ultrasonographic study of the vascular wall should be included in the follow-up of HIV infected patients.

Interaction of calmodulin with lactoferrin.

Calmodulin, as a major intracellular calcium-binding protein, regulates many Ca(2+)-dependent enzymes and plays an important role in a wide spectrum of cellular functions of the eukaryotes. Interaction between calmodulin and human lactoferrin, a 78 kDa protein with antibacterial properties, was found in the presence of Ca2+ using (i) a method for the detection of calmodulin binding proteins with biotinylated calmodulin, (ii) affinity chromatography on an agarose-calmodulin column with subsequent detection by an enzyme-linked immunosorbent assay (ELISA). The binding of calmodulin to lactoferrin blocked the ability of lactoferrin to agglutinate Micrococcus lysodeikticus.

Identification of a lactoferrin-binding protein in Prevotella nigrescens.

A 40-kDa lactoferrin-binding protein was identified in a strain of Prevotella nigrescens isolated from a patient with periodontitis. The protein was purified by affinity column chromatography using a Sepharose-lactoferrin column and detergent-solubilized membranes. The N-terminal sequence revealed no apparent similarities with any other sequenced bacterial protein. The native conformation of the 40-kDa protein was a condition to bind either iron-free or iron-saturated lactoferrin. A possible function of this Lf-binding protein could be related with an iron acquisition mechanism in P. nigrescens.

Relationship between antibacterial activity and cell surface binding of lactoferrin in species of genus Micrococcus.

Human lactoferrin was bactericidal in vitro for Micrococcus luteus but not for other Micrococcus species (M. radiophilus, M. roseus and M. varians). A correlation between the binding of lactoferrin to the bacterial surface and the antimicrobial action was observed. Viability assays showed that ferric, but not ferrous, salts prevented binding and consequently M. luteus was not killed. The unsaturated form of lactoferrin showed a greater affinity than that of the iron-saturated molecule for lipomannan, a lipoglycan present on the cell wall of M. luteus, supporting the role for lipomannan as one of the possible binding sites of lactoferrin on M. luteus.

Binding and degradation of lactoferrin by Porphyromonas gingivalis, Prevotella intermedia and Prevotella nigrescens.

The ability of laboratory and clinical strains of Porphyromonas gingivalis, Prevotella intermedia and Prevotella nigrescens to bind and to degrade lactoferrin (Lf) has been assessed. Lf bound readily to whole cells of each species apparently via high-affinity site and one or more low-affinity sites. P. gingivalis showed a lower affinity for Lf than the other two species (P < 0.001). Virtually all strains of P. gingivalis completely degraded Lf under the conditions employed, whereas P. intermedia and P. nigrescens showed only partial degradation. These data suggest that Lf binds to a high-affinity receptor on all these bacteria and, particularly in the case of P. gingivalis, is then degraded by cell-associated proteases. This property may provide protection to the cell against the effects of Lf in periodontal sites and so is a possible virulence factor in disease. There was no association between the ability to degrade Lf and whether the strains had originated from healthy or diseased oral sites.

Influence of mastication on gastric emptying.

The role of mastication on digestion efficiency remains to be demonstrated. This study investigates whether masticatory function influences gastric emptying rate. Twelve normal volunteers were studied on two occasions after ingestion of the same test meal containing ham cubes, crackers, and egg (mixed with 13C-octanoic acid), chewed, in random order, either with 50 masticatory cycles or with 25 cycles, swallowing ham cubes whole. Lag phase (Tlag) and gastric half-emptying time (T1/2) were measured by means of the 13C-octanoic acid breath test. Trituration performance was assessed by the sieve test, and was expressed as the percentage of ham particles < or = 1 mm after 50 masticatory cycles. Tlag and T1/2 were significantly shorter when the meal was chewed with 50 cycles than with 25 cycles (Tlag 25.9+/-3.8 vs. 36.4+/-4.1 min, p=0.017; T1/2 49.1+/-5.7 vs. 62.5+/-6 min, p=0.009). Trituration performance was inversely related to both Tlag (r=0.621, p=0.031) and T1/2 (r=0.699, p=0.012). Comminution of food influences significantly gastric emptying rates.

Recurrence of unilateral retinoblastoma following radiation therapy.

A retrospective analysis of 65 unilateral retinoblastoma patients treated initially with external beam radiation, revealed that 25 eyes (38.5%) developed local recurrence of retinoblastoma. The mean age at diagnosis was 1.8 years for patients who developed recurrences vs. 0.9 years for those who did not. Ninety-six percent of the recurrences occurred less than two years from the age at diagnosis; the amount of time from the end of external beam radiation treatment until a tumor recurred was independent of the age at diagnosis. The initial largest basal diameter was 10.7 DD for tumors which later recurred and 5.9 DD for tumors that were cured. Sixty-nine percent of eyes in groups III-V had tumor recurrence, and 10% of eyes in groups I-II had recurrence. All but one eye (24 eyes) that developed recurrence were enucleated. Family history of retinoblastoma, location of the tumor, gender, and laterality did not significantly correlate with the mean age of initial diagnosis for tumors that recurred or the mean time of onset for recurrence.

Plasma lipids as a risk factor in peripheral vascular disease.

Plasma lipids were tested in 59 patients with symptomatic peripheral vascular disease (PVD) (confirmed by angiographic and, in many cases, operative examinations) and compared with the lipid balance in 47 nonarteriopathic subjects constituting the control group. Of all the elements considered, only the hypertriglyceridemia and the fall in the HDL cholesterol/total cholesterol ratio showed a statistically significant difference between the two groups. In particular, there was a significant difference between the two groups. In particular, there was a significant difference in the triglyceridemia present in the arteriopathic patients, as evidenced by the double check afforded by the frequency test (PVD: 25/59; control: 8/47; p less than 0.01) and the averages test (PVD: 201 +/- 131; control: 138 +/- 98; p less than 0.01).