[Atypical femoral fractures due to the use of bisphosphonates. Experience of two institutions]. / Fracturas femorales atípicas por el uso de bifosfonatos. Experiencia de dos instituciones.

INTRODUCTION: bisphosphonates are used for the management of postmenopausal osteoporosis with high risk of fracture, glucocorticoid-induced osteoporosis, Paget's disease and hypercalcemia; as well as an adjuvant for the management of hyperparathyroidism. Bisphosphonates have been associated with previously unknown adverse effects, including atypical femur fractures. OBJECTIVE: to analyze the relationship of the history of bisphosphonate (BF) use as a risk factor for presenting atypical femur fractures (AFF). MATERIAL AND METHODS: patients aged 40 years or older from two hospital centers seen from 2009 to 2018 for femur fracture were included. The radiographic studies of 441 records were reviewed, from which the fracture site was defined. Subtrochanteric (SF) and diaphyseal (DF) femur fractures were analyzed applying the criteria of the second report of the American Society for Bone and Mineral Research for case definition of AFF. Finally, the consumption of bisphosphonates in these groups was investigated to estimate a measure of association. RESULTS: of the 441 clinical records, 98 (22.2%) were male and 343 (77.7%) were female with a mean age of 77.8 (40-103) years. Fifty-nine FS/FD were identified, of which 53% (31 records) were categorized as AFF. BF use was determined in 80.6% of patients with AFF and 3.57% in FS/FD. BF use was significantly associated with the presence of AFF (OR: 112, p 0.000, CI 95%: 12.6-1001). CONCLUSIONS: BF use significantly increases the risk of presenting AFF. AFF in patients who used BF occurred after a minimum consumption of 24 months.

INTRODUCCIÓN: los bifosfonatos se usan para el manejo de osteoporosis postmenopáusica con riesgo elevado de fractura, osteoporosis inducida por glucocorticoides, enfermedad de Paget e hipercalcemia; así como coadyuvante para manejo del hiperparatiroidismo. Los bifosfonatos se han asociado a efectos adversos previamente desconocidos dentro de los que se encuentran fracturas de fémur de trazo atípico. OBJETIVO: analizar la relación del antecedente de uso de bifosfonatos (BF) como factor de riesgo para presentar fracturas atípicas de fémur (FAF). MATERIAL Y MÉTODOS: se incluyeron pacientes de 40 años o más de dos centros hospitalarios atendidos desde 2009 a 2018 por fractura de fémur. Se revisaron los estudios radiográficos de 441 registros, de los cuales se definió el sitio de fractura. Se analizaron las fracturas de fémur subtrocantéricas (FS) y diafisarias (FD) aplicando los criterios del segundo reporte de la American Society for Bone and Mineral Research para la definición de caso de FAF. Finalmente, se indagó el consumo de bifosfonatos en estos grupos para para estimar una medida de asociación. RESULTADOS: de los 441 registros clínicos, 98 (22.2%) fueron del sexo masculino y 343 (77.7%) del femenino, con edad promedio de 77.8 (40-103) años. Se identificaron 59 FS/FD, de las cuales 53% (31 registros) fueron catalogadas FAF. El consumo de BF se determinó en 80.6% de pacientes con FAF y en 3.57% con FS/FD. El uso de BF se asoció significativamente con la presencia de FAF (OR: 112, p 0.000, IC 95%: 12.6-1001). CONCLUSIONES: el uso de BF aumenta significativamente el riesgo de presentar FAF. Las FAF en pacientes que usaron BF se presentó tras un consumo mínimo de 24 meses.

Taxonomic study of the Phyllosoma complex and other triatomine (Insecta: Hemiptera: Reduviidae) species of epidemiological importance in the transmission of Chagas disease: using ITS-2 and mtCytB sequences.

The purpose of this work was to clarify the taxonomy and phylogenetic relationship of the Phyllosoma complex and other important vectors in Mexico. The internal transcribed spacer 2 (ITS-2) of rDNA and the cytochrome B gene of mtDNA (mtCytB) were analyzed for the following species of triatomine: Triatoma bassolsae, T. longipennis, T. mazzottii, T. mexicana, T. pallidipennis, T. picturata, and T. phyllosoma belonging to the Phyllosoma complex, as well as T. dimidiata, T. rubida, T. infestans, and Rhodnius prolixus. The results obtained with the analysis of the ITS-2 sequences showed that the Phyllosoma complex species could not be phylogenetically separated, since T. bassolsae and T. pallidipennis, as well as T. phyllosoma and T. mazzottii were indistinguishable. In contrast, the mtCytB gene separates each one of these triatomine species. The results support the proximity of all seven species currently included in the Phyllosoma complex as well as the exclusion of T. dimidiata. For the first time T. lecticularia and T. rubida were analyzed and were also shown to be related to the Phyllosoma complex.

Chronic recurrent varicella-zoster virus keratitis confirmed by polymerase chain reaction testing.

PURPOSE: To report a case of chronic recurrent varicella virus epithelial keratitis in a child. DESIGN: Case report. METHODS: Clinical examination and polymerase chain reaction analysis of corneal epithelium. RESULTS: A 10-year-old healthy child developed chronic recurrent varicella virus keratitis with pseudodendrites after recovering from systemic varicella. Analysis of the debrided pseudodendrites was repeatedly positive for VZV DNA and negative for HSV DNA. Treatment with oral acyclovir and topical corticosteroid drops was effective in eliminating the pseudodendrites; however, recurrences occurred once the medications were discontinued. CONCLUSIONS: Varicella virus epithelial keratitis in children can be a recurrent chronic condition requiring prolonged treatment.

Analysis of the herpes simplex virus type 1 UL6 gene in patients with stromal keratitis.

Recent work suggests that herpes simplex virus (HSV) stromal keratitis in the mouse is caused by autoreactive T lymphocytes triggered by a 16 amino acid region of the HSV UL6 protein (aa299-314), Science 279, 1344-1347). In the present study we sought to determine whether genetic variation of this presumed autoreactive UL6 epitope is responsible for different pathogenic patterns of human HSV keratitis. To accomplish this, we sequenced the HSV UL6 gene from ocular isolates of 10 patients with necrotizing stromal keratitis, 7 patients with recurrent epithelial keratitis, and 8 patients with other forms of HSV keratitis. The sequences obtained predicted identical UL6(299-314) epitopes for all 25 viral isolates. Furthermore, the upstream sequence of all isolates was free of insertions, deletions, and stop codons. We conclude that different pathogenic patterns of human HSV keratitis occur independent of genetic variation of the HSV UL6 (299-314) epitope.

Normas de bioseguridad en el quiròfano: conocimiento y aplicaciòn por el anestesiòlogo / Norms of bioseguridad in the quiròfano: knowledge and aplicaciòn by anestesiologo

Las normas de bioseguridad son un complejo conjunto de acciones que tienden a conservar y mejorar las condiciones de vida del personal mèdico y de otros niveles de formaciòn que se relacionan en forma directa o indirecta con el manejo del paciente y el entorno que lo rodea, establecidas a nivel mundial con el propòsito de precautelar la salud de estos tres componentes (pacientes, trabajadores hospitalarios y medio ambiente). El objetivo del estudio fue establecer un diagnòstico sobre el problema planteado, sus causas y ofrecer alternativas a los mismos. Para el efecto se realizò un estudio transversal, observacional, descriptivo, que se restringiò a aquellas normas aplicables dentro del quiròfano y sobretodo al accionar diario de los mèdicos anestesiòlogos...

Mediation of Cryptosporidium parvum infection in vitro by mucin-like glycoproteins defined by a neutralizing monoclonal antibody.

The protozoan parasite Cryptosporidium parvum is a significant cause of diarrheal disease worldwide. Attachment to and invasion of host intestinal epithelial cells by C. parvum sporozoites are crucial steps in the pathogenesis of cryptosporidiosis. The molecular basis of these initial interactions is unknown. In order to identify putative C. parvum adhesion- and invasion-specific proteins, we raised monoclonal antibodies (MAbs) to sporozoites and evaluated them for inhibition of attachment and invasion in vitro. Using this approach, we identified two glycoproteins recognized by 4E9, a MAb which neutralized C. parvum infection and inhibited sporozoite attachment to intestinal epithelial cells in vitro. 4E9 recognized a 40-kDa glycoprotein named gp40 and a second, >220-kDa protein which was identified as GP900, a previously described mucin-like glycoprotein. Glycoproteins recognized by 4E9 are localized to the surface and apical region of invasive stages and are shed in trails from the parasite during gliding motility. The epitope recognized by 4E9 contains alpha-N-acetylgalactosamine residues, which are present in a mucin-type O-glycosidic linkage. Lectins specific for these glycans bind to the surface and apical region of sporozoites and block attachment to host cells. The surface and apical localization of these glycoproteins and the neutralizing effect of the MAb and alpha-N-acetylgalactosamine-specific lectins strongly implicate these proteins and their glycotopes as playing a role in C. parvum-host cell interactions.

Molecular cloning and expression of a gene encoding Cryptosporidium parvum glycoproteins gp40 and gp15.

Cryptosporidium parvum is a significant cause of diarrheal disease worldwide. The specific molecules that mediate C. parvum-host cell interactions and the molecular mechanisms involved in the pathogenesis of cryptosporidiosis are unknown. In this study we have shown that gp40, a mucin-like glycoprotein, is localized to the surface and apical region of invasive stages of the parasite and is shed from its surface. gp40-specific antibodies neutralize infection in vitro, and native gp40 binds specifically to host cells, implicating this glycoprotein in C. parvum attachment to and invasion of host cells. We have cloned and sequenced a gene designated Cpgp40/15 that encodes gp40 as well as gp15, an antigenically distinct, surface glycoprotein also implicated in C. parvum-host cell interactions. Analysis of the deduced amino acid sequence of the 981-bp Cpgp40/15 revealed the presence of an N-terminal signal peptide, a polyserine domain, multiple predicted O-glycosylation sites, a single potential N-glycosylation site, and a hydrophobic region at the C terminus, a finding consistent with what is required for the addition of a GPI anchor. There is a single copy of Cpgp40/15 in the C. parvum genome, and this gene does not contain introns. Our data indicate that the two Cpgp40/15-encoded proteins, gp40 and gp15, are products of proteolytic cleavage of a 49-kDa precursor protein which is expressed in intracellular stages of the parasite. The surface localization of gp40 and gp15 and their involvement in the host-parasite interaction suggest that either or both of these glycoproteins may serve as effective targets for specific preventive or therapeutic measures for cryptosporidiosis.

Detection of anti-colon antibodies in inflammatory bowel disease using human cultured colonic cells.

BACKGROUND: Investigation of anti-colon antibodies may be simplified if a sensitive method and homogeneous source of antigen were available. AIMS: To examine the anti-colon antibody response using human colonic carcinoma cell lines as antigen. SUBJECTS: Patients with inflammatory bowel disease and other gastrointestinal disorders and healthy controls were studied. METHODS: Comparative enzyme linked immunosorbent assays (ELISAs) were performed to assess the value of whole Caco-2, HT-29, and LS-180 cells as antigen. The antigenic determinants of the immune response were characterised by western blot analysis. RESULTS: Sera demonstrated immunoreactivity against each of the cell lines, but different epitopes were recognised. Applying whole Caco-2 cells as antigen in an ELISA, the prevalence of anti-colon antibodies was significantly greater in patients with ulcerative colitis (36%) than Crohn's disease (13%), other gastrointestinal disorders (13%) and healthy controls (0) (p<0. 05). The immune response was not associated with one predominant antigen. CONCLUSIONS: Fixed whole cell ELISA is a simple and feasible method for studying the anti-colon antibody response. This response is non-specific, being directed against multiple antigens, and is likely to be an epiphenomenon of inflammatory bowel disease, more so for ulcerative colitis than Crohn's disease.

Generation of a polyclonal Fab phage display library to the protozoan parasite Cryptosporidium parvum.

We had developed a technology for creation of recombinant polyclonal antibody libraries, standardized perpetual mixtures of polyclonal whole antibodies for which the genes are available and can be altered as desired. We report here the first phase of generating a polyclonal antibody library to Cryptosporidium parvum, a protozoan parasite that causes severe disease in AIDS patients, for which there is no effective treatment. BALB/c mice, immunized by neonatal oral infection with oocysts followed by intraperitoneal immunization with a sporozoite/oocyst preparation of C. parvum, were used for construction of a Fab phage display library in a specially-designed bidirectional vector. This library was selected for reactivity to an oocyst/sporozoite preparation, and was shown to be antigen-specific and diverse. Following mass transfer of the selected variable region gene pairs to appropriate mammalian expression vectors, such anti-C. parvum Fab phage display libraries could be used to develop chimeric polyclonal antibody libraries, with mouse variable regions and human constant regions, for passive immunotherapy of C. parvum infection.

Cryptosporidium: molecular basis of host-parasite interaction.

Host-parasite interactions occur at a number of stages during the process of infection with Cryptosporidium. Until recently, very little was known about the molecular basis of these interactions or of specific parasite and host molecules involved in them. Within the past decade significant advances have been made in our understanding of Cryptosporidium host-parasite interactions and in identifying molecules involved in them. However, with most interactions the story is far from complete and a number of gaps remain to be filled. This chapter reviews the existing knowledge of the molecular basis of various host-parasite interactions and of specific molecules that may be involved in them, and identifies areas in which further investigation is necessary. Identification of these molecules and elucidation of molecular mechanisms underlying the host-parasite interaction are of vital importance in developing strategies to combat cryptosporidiosis by targeted chemo- and immunotherapy.

Ocular flora of patients with AIDS compared with those of HIV-negative patients.

PURPOSE: To determine whether there are quantitative or qualitative differences in the ocular flora of patients with acquired immunodeficiency syndrome (AIDS) compared with human immunodeficiency virus (HIV)-negative patients. METHODS: Forty patients with AIDS and 42 HIV-negative controls were sex and age matched. All subjects had a detailed anterior segment examination, including Schirmer's test, rose bengal staining, and quantitative cultures of the conjunctiva and lids. Statistical evaluation of the relation between AIDS, keratoconjunctivitis sicca (KCS), and ocular flora was performed. RESULTS: No differences were observed in the types or numbers of organisms isolated from the conjunctiva or lids of patients with AIDS and HIV-negative subjects. Ocular flora was not influenced by use of systemic antibiotics, level of immunosuppression as measured by CD4 lymphocyte counts, KCS, or other ocular-surface disease. One AIDS patient was colonized by large numbers of Haemophilus influenzae OU with minimal clinical signs of inflammation or infection. CONCLUSION: There do not appear to be any differences in the ocular flora of HIV-negative patients and patients with AIDS. Presence of KCS and level of immunosuppression do not appear to affect the ocular flora in patients with AIDS.

Embarazo precoz y maternidad en solteras como variables de paternidad responsable y su relación con inadecuada educación sexual / Unmarried precocious pregnancy and maternity in like variables of responsible paternity and their relation with inadequate sexual education

Expone que mediante el presente estudio se establece y confirma una clara relación sexual entre la deficiente educación sexual y la alta incidencia de embarazo precoz y maternidad en solteras, dos de los principales problemas detectados en las poblaciones de Mira y la Libertad (Provincia del Carchi). Se demuestra que el nivel educativo es semejante en las dos poblaciones, existiendo diferencias significativas con las publicadas a nivel nacional.

Antibiotic supplementation of intraocular irrigating solutions. An in vitro model of antibacterial action.

PURPOSE: The addition of antibiotics to infusion solutions for cataract surgery is becoming increasingly popular. The authors developed an in vitro model to evaluate antibacterial effects of this use of antibiotics. METHODS: Clinical isolates and/or reference strains of the following organisms were examined: coagulase-negative Staphylococcus spp, Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus viridans, Streptococcus spp, Enterococcus spp, Proprionibacterium acnes, Moraxella nonliquifaciens, and Pseudomonas aeruginosa. Standardized suspensions of each organism were incubated with a control solution (Balanced Salt Solution) or Balanced Salt Solution containing the following antibiotics: vancomycin (20 micrograms/ml) or gentamicin (8 micrograms/ml) or gentamicin and vancomycin combined (8 and 20 micrograms/ml, respectively). Suspensions were incubated for 30, 60, and 120 minutes at room temperature. Samples were centrifuged, and the organisms were washed with Balanced Salt Solution before quantitative culturing. Each organism also was incubated for 48 hours in Mueller-Hinton broth with the same antibiotic concentrations. RESULTS: Most of the organisms were not affected by exposure to the antibiotics for up to 140 minutes. P. aeruginosa and M. nonliquifaciens were exceptions, decreasing in colony numbers even with 30 minutes of exposure. Several Staphylococcus spp yielded variable results. All organisms demonstrated nearly complete inhibition of growth when exposed for an extended time to the appropriate antibiotic in broth. CONCLUSIONS: Exposure to antibiotics for a short period of time, such as during intraocular surgery, generally has no effect on organisms commonly responsible for endophthalmitis. The use of antibiotics in this manner should be critically reassessed until further study.

Small intestinal injury in a neonatal rat model of giardiasis is strain dependent.

BACKGROUND & AIMS: The factors that determine the severity of giardiasis are poorly understood. Host factors are important, but parasite virulence may also play a role. The aim of this study was to compare the apparent virulence of three genotypically different Giardia isolates (PO1, VNB3, and WB). METHODS: Infection rates, parasite loads, structural damage, disaccharidase activity, and water and electrolyte absorption were observed at 10 days after inoculation in a neonatal rat model of infection. RESULTS: DNA fingerprinting showed differences between isolates studied. The infective rate varied between 67% and 100%. There were no differences in intestinal parasite load. Infection with strains PO1 and WB, but not with VNB3, was associated with a reduction in villus height. There was precocious expression of sucrase at 10 days after inoculation in all infected groups. Water absorption of a plasma electrolyte solution was decreased in VNB3-infected animals when compared with PO1- and WB-infected animals and controls. Water absorption and lactose hydrolysis were impaired during perfusion with a lactose-containing solution in all infected groups. CONCLUSIONS: Three genotypically different Giardia isolates that infect neonatal rats with the same trophozoite load differ in their ability to cause functional mucosal damage. Infection with Giardia lamblia induced precocious expression of sucrase activity and impaired mucosal absorption.

Phenotypic and genotypic variation in Giardia lamblia isolates during chronic infection.

Two Giardia isolates were axenised in vitro after recovery by duodenal aspiration from a man with hypo-gamma globulinaemia and chronic giardiasis, before and after three unsuccessful courses of metronidazole. In vitro drug sensitivity assays showed that the pretreatment isolate was sensitive to metronidazole with minimum inhibitory concentration (MIC) and dose that inhibited growth by 50% (ED50) values of 0.1 and 0.03 mumol/l, respectively. The post-treatment isolate was 20-fold more resistant (MIC and ED50 4.3 and 0.58 mumol/l, respectively). Differences between these isolates were also found in the surface protein profiles after radioiodination, metabolic labelling patterns with 35S-methionine, malic enzyme isoenzyme patterns, and by DNA fingerprinting with a M-13 bacteriophage probe. The phenotypic and genotypic differences between the pretreatment and post-treatment isolates suggest that we have isolated two different strains from the same patient and that treatment with metronidazole resulted in selection of the more resistant strain.

Impaired IgA response to Giardia heat shock antigen in children with persistent diarrhoea and giardiasis.

The serum antibody response in Gambian children with persistent diarrhoea and giardiasis has been studied. Total serum IgG, IgA, and IgM concentrations were increased in these patients as compared with controls from the same area. Determination of the concentrations of Giardia specific antibodies by enzyme linked immuno adsorbent assay (ELISA), however, revealed that only IgM was raised while those of IgA and IgG were similar to the controls. Analysis of the antigenic determinants of the IgG and IgA responses by immunoblotting showed that patients with chronic infection unlike those who clear the infection have no IgA response to a 57 kDa Giardia heat shock antigen. The association of high concentrations of Giardia specific IgM, low concentrations of Giardia specific IgA and IgG and inability to clear the infection suggests that the switch from an IgM to an IgG or IgA response is inefficient.