A novel Chilean salmon fish backbone-based nanoHydroxyApatite functional biomaterial for potential use in bone tissue engineering

Introduction

Given the ensuing increase in bone and periodontal diseases and defects, de novo bone repair and/or regeneration strategies are constantly undergoing-development alongside advances in orthopedic, oro-dental and cranio-maxillo-facial technologies and improvements in bio-/nano-materials. Indeed, there is a remarkably growing need for new oro-dental functional biomaterials that can help recreate soft and hard tissues and restore function and aesthetics of teeth/ dentition and surrounding tissues. In bone tissue engineering, HydroxyApatite minerals (HAp), the most stable CaP/Calcium Phosphate bioceramic and a widely-used material as a bone graft substitute, have been extensively studied for regenerative medicine and dentistry applications, including clinical use. Yet, limitations and challenges owing principally to its bio-mechanical strength, exist and therefore, research and innovation efforts continue to pursue enhancing its bio-effects, particularly at the nano-scale.

Methods

Herein, we report on the physico-chemical properties of a novel nanoHydroxyApatite material obtained from the backbone of Salmon fish (patent-pending); an abundant and promising yet under-explored alternative HAp source. Briefly, our nanoS-HAp obtained via a modified and innovative alkaline hydrolysis-calcination process was characterized by X-ray diffraction, electron microscopy, spectroscopy, and a cell viability assay.

Results and Discussion

When compared to control HAp (synthetic, human, bovine or porcine), our nanoS-HAp demonstrated attractive characteristics, a promising biomaterial candidate for use in bone tissue engineering, and beyond.

Evaluation of the Effect of Binary Fly Ash-Lime Mixture on the Bearing Capacity of Natural Soils: A Comparison with Two Conventional Stabilizers Lime and Portland Cement

This study evaluates a binary mixture of fly ash and lime as a stabilizer for natural soils. A comparative analysis was performed on the effect on the bearing capacity of silty, sandy and clayey soils after the addition of lime and ordinary Portland cement as conventional stabilizers, and a non-conventional product of a binary mixture of fly ash and Ca(OH)₂ called FLM. Laboratory tests were carried out to evaluate the effect of additions on the bearing capacity of stabilized soils by unconfined compressive strength (UCS). In addition, a mineralogical analysis to validate the presence of cementitious phases due to chemical reactions with FLM was performed. The highest UCS values were found in the soils that required the highest water demand for compaction. Thus, the silty soil added with FLM reached 10 MPa after 28 days of curing, which was in agreement with the analysis of the FLM pastes, where soil moistures higher than 20% showed the best mechanical characteristics. Furthermore, a 120 m long track was built with stabilized soil to evaluate its structural behavior for 10 months. An increase of 200% in the resilient modulus of the FLM-stabilized soils was identified, and a decrease of up to 50% in the roughness index of the FLM, lime (L) and Ordinary Portland Cement (OPC)-stabilized soils compared to the soil without addition, resulting in more functional surfaces.

[Anterior shoulder instability with Hill-Sachs on-track. Bankart or Bankart-remplissage?]

INTRODUCTION

in patients with anterior glenohumeral (GH) instability together with an off-track or engaging Hill-Sachs (HS) defect, Bankart-remplissage (B-R) surgery reduces the recurrence rate when compared to Bankart (B) surgery alone. There is controversy regarding whether the recurrence rate also decreases in patients with on-track or non-engaging Hill-Sachs defects.

OBJECTIVE

to compare the recurrence rate and clinical evolution of patients with anterior glenohumeral instability with 'on-track' Hill-Sachs defect treated with either B or B-R surgery.

MATERIAL AND METHODS

non-randomized, retrospective, single-center cohort study of patients with anterior glenohumeral instability and on-track Hill-Sachs defect, operated between January 2010 and December 2018. Patients operated with B versus B-R were compared. Recurrence, complications and re-operation were recorded. In addition, VAS, SSV, WOSI and qDASH scores were obtained and compared in both groups.

RESULTS

of the 105 patients who met the inclusion criteria, 78 (74.3%) patients had a complete follow-up (52 B and 26 B-R, 4.3 years median follow-up). There was a higher recurrence rate in group B compared to B-R, with this difference not reaching statistical significance (17.3% vs 7.7%, p = 0.21). There were no significant differences in residual pain, feeling of instability, complications or VAS, qDASH, SSV or WOSI scores between both groups. In the subgroup analysis, patients who practiced contact sports and were operated with B showed higher recurrence rates (24.1% vs 0%, p = 0.08) and complications (41.4% vs 18.2%, p = 0.16) when compared to B + R, although these differences were not significant.

CONCLUSION

there were no significant differences in recurrence rates and functional evolution between patients with anterior glenohumeral instability operated with B or B-R surgery. Comparative, prospective studies should be performed to establish definitive recommendations.

Evaluation of recorded video-observed therapy for anti-tuberculosis treatment

BACKGROUND: Asynchronous video directly observed therapy (VDOT) may reduce tuberculosis (TB) program costs and the burden on patients. We compared VDOT performance across three cities in the United States, each of which have TB incidence rates above the national average.METHODS: Patients aged ≥18 years who are currently receiving directly observed anti-TB treatment were invited to use VDOT for monitoring treatment. Pre- and post-treatment interviews and medical records were used to assess site differences in treatment adherence and patient characteristics and perceptions.RESULTS: Participants were enrolled in New York City, NY (n = 48), San Diego, CA (n = 52) and San Francisco, CA, USA (n = 49). Overall, the mean age was 41 years (range 18-87); 59% were male; most were Asian (45%) or Hispanic/Latino (30%); and 77% were foreign-born. The median fraction of expected doses observed (FEDO) was 88% (IQR 76-96). At follow-up, 97% thought VDOT was "very or somewhat easy to use" and 95% would recommend VDOT to other TB patients. Age, race/ethnicity, annual income, and country of birth differed by city (P < 0.05), but FEDO and VDOT perceptions did not.CONCLUSIONS: TB programs in three large US cities observed a high FEDO using VDOT while minimizing staff time and travel. Similar findings across sites support VDOT adoption by other large, urban TB programs.

Hard tissue volumetric and soft tissue contour linear changes at implants with different surface characteristics after experimentally induced peri-implantitis: an experimental in vivo investigation

OBJECTIVE

To evaluate the hard tissue volumetric and soft tissue contour linear changes in implants with two different implant surface characteristics after a ligature-induced peri-implantitis.

MATERIAL AND METHODS

In eight beagle dogs, implants with the same size and diameter but distinct surface characteristics were placed in the healed mandibular sites. Test implants had an external monolayer of multi-phosphonate molecules (B+), while control implants were identical but without the phosphonate-rich surface. Once the implants were osseointegrated, oral hygiene was interrupted and peri-implantitis was induced by placing subgingival ligatures. After 16 weeks, the ligatures were removed and peri-implantitis progressed spontaneously. Bone to implant contact (BIC) and bone loss (BL) were assessed three-dimensionally with Micro-Ct (μCT). Dental casts were optically scanned and the obtained digitalized standard tessellation language (STL) images were used to assess the soft tissue vertical and horizontal contour linear changes.

RESULTS

Reduction of the three-dimensional BIC percentage during the induction and progression phases of the experimental peri-implantitis was similar for both the experimental and control implants, without statistically significant differences between them. Soft tissue analysis revealed for both implant groups an increase in horizontal dimension after the induction of peri-implantitis, followed by a decrease after the spontaneous progression period. In the vertical dimension, a soft tissue dehiscence was observed in both groups, being more pronounced at the buccal aspect.

CONCLUSIONS

The added phosphonate-rich surface did not provide a more resistant environment against experimental peri-implantitis, when assessed by the changes in bone volume and soft tissue contours.

CLINICAL RELEVANCE

Ligature-induced peri-implantitis is a validated model to study the tissue changes occurring during peri-implantitis. It was hypothesized that a stronger osseointegration mediated by the chemical bond of a phosphonate-rich implant surface would develop an environment more resistant to the inflammatory changes occurring after experimental peri-implantitis. These results, however, indicate that the hard and soft tissue destructive changes occurring at both the induction and progression phases of experimental peri-implantitis were not influenced by the quality of osseointegration.

Usefulness of intestinal ultrasound in inflammatory bowel disease

Imaging techniques play a fundamental role in the initial diagnosis and follow-up of inflammatory bowel disease. Intestinal ultrasound has high sensitivity and specificity in patients with suspected Crohn's disease and in the detection of inflammatory activity. This technique enables the early diagnosis of intra-abdominal complications such as stenosis, fistulas, and abscesses. It has also proven useful in monitoring the response to treatment and in detecting postsurgical recurrence. Technical improvements in ultrasound scanners, technological advances such as ultrasound contrast agents and elastography, and above all increased experience have increased the role of ultrasound in the evaluation of the gastrointestinal tract. The features that make ultrasound especially attractive include its wide availability, its noninvasiveness and lack of ionizing radiation, its low cost, and its good reproducibility, which is important because it is easy to repeat the study and the study is well tolerated during follow-up. This review summarizes the role of intestinal ultrasound in the detection and follow-up of inflammatory bowel disease.

Relative permittivity estimation of wheat starch: A critical property for understanding electrostatic hazards

Wheat starch is a widely used material in the food, pharmaceutical and entertainment industry not considered hazard but recently associated to dust explosions during processing and handling. How an insulating starch grain is charged and how its ability to be polarized is affected by environmental conditions such as temperature, humidity and frequency? are fundamental questions that must be explored in order to understand the dust explosion phenomena. Here we investigate the dependence of temperature, humidity and low-frequency on the relative permittivity of wheat starch. We characterized starch at the micro and macro scales using atomic force microscopy-based techniques and capacitive planar sensor-based measurements respectively. The results show high values of permittivity (˜80) at the microscale (single starch grains) compared to the low values (10-20) at the macroscale (20 mg of wheat starch). The differences are attributed to the Maxwell-Wagner-Sillars interfacial polarization process on individual grains and potential charge exchange between grains. Permittivity is a critical property to investigate starch electrostatic hazards.

130 In vitro embryo production using frozen semen from cloned and non-cloned Bos indicus bulls

Reproductive biotechnology has continued to evolve rapidly, allowing the development of techniques to increase reproductive efficiency and contribute to the genetic improvement of cattle. Some of these techniques include the in vitro maturation and IVF of oocytes, sperm sexing and cloning. These modern assisted reproductive techniques can help produce offspring of desired genetic characteristics and of a pre-determined sex. However, studies of the bull’s contribution to in vitro reproductive performance are scarce in the Brahman breed. The aim of this study was to compare oocyte maturation and embryo production in vitro using frozen semen from 5 Brahman bulls (Bos indicus), cloned (n=1) and non-cloned (n=4), with characteristics and genetics of high commercial value. The age of the bulls at the time of semen collection and cryopreservation ranged from 2 to 7 years. The oocytes were obtained on 2 different dates (45 days between collections) using pooled oocytes collected by ovum pickup at random stages of the oestrous cycle, from a total of 15 Brahman donor cows. Oocytes were transported to a laboratory in the State of Chiapas, Mexico (Genemex Internacional). The oocytes were cultured in maturation medium for 24h. For IVF, conventional semen was used from one bull (B1) and his clone (B12), the grandson of B1 (B2), and 2 non-related bulls (B3 and B4). The gametes were co-incubated for 22h and afterward placed in medium for embryo development and cultured for 7 days in a humid atmosphere with 5% CO2 in air. Of the matured oocytes, 36/43 (84%), 16/32 (50%), 101/143 (70%), 46/67 (68%) and 53/65 (81%) were fertilized using semen from B1, B12, B2, B3 and B4, respectively. Of the fertilized oocytes, 15/30 (50%), 8/16 (50%), 45/101 (44%), 21/46 (45%) and 18/53 (34%) resulted in transferrable embryos, corresponding to semen from the same bulls, respectively. This would appear to be the first scientific report in Mexico about the use of semen from a cloned bull for in vitro embryo production. In IVF, similar results were observed between B1 and a non-related bull (B4). Similar results in transferrable embryos were observed between B1 and B12 but also similar to a related bull (B3) and a non-related bull (B4). A Fisher’s exact test of the IVF results comparing B1 and B12 found a significantly (P&lt;0.05) higher number of fertilized oocytes for B1. However, a significant difference was not found (P&gt;0.05) concerning the number of transferrable embryos produced by these two bulls. In conclusion, the Brahman bulls in this study differ in their contribution to IVF and embryo production. Further studies are required to determine the factors responsible for such effects, e.g. age differences or clone versus non-clone mosaicism. Results from this research contribute to the study and development of assisted reproductive techniques for increasing in vitro production efficiency in Zebu cattle. We thank the Rosales family, from El Herradero Ranch, in the State of Campeche, Mexico, for allowing the use of their cattle for this project.

87 Assessment of pregnancy success following transfer of embryos produced in vitro using frozen - thawed semen from cloned and noncloned Bos indicus bulls

Assisted reproductive technologies (ART) continue to develop rapidly, allowing for the development of techniques to increase reproductive efficiency and contribute to the genetic improvement of cattle. Some of these techniques include in vitro production (IVP) of embryos and embryo transfer. These modern ART can help produce offspring with highly desirable characteristics. However, there is a lack of information on the percentage of pregnancies obtained following transfer (P/ET) of IVP embryos derived using semen of cloned Bos indicus bulls. The objective of this study was to compare embryo transfer results of IVP embryos created using frozen-thawed semen from 5 Brahman bulls (Bos indicus) with characteristics and genetics of high commercial value. The embryos were produced on two different dates, 45 days apart, using pooled oocytes harvested by ovum pickup from 15 Brahman cows at random stages of the oestrous cycle. Procedures for IVP were performed in a commercial laboratory (Genemex Internacional) in the state of Chiapas, Mexico. For IVF, conventional semen was used from 1 bull (B1) and his clone (B12), the grandson of B1 (B2), and from 2 nonrelated bulls (B3 and B4). A total of 100 embryos were transferred nonsurgically by a private practitioner on a ranch in the state of Campeche, Mexico. The recipients were commercial crossbred cows synchronized using a FTET program. On Day 0, recipients received an intravaginal device containing 1.9g of progesterone (CIDR) and 2mg of oestradiol benzoate IM. On Day 8, the CIDR was removed and cows received 25mg of dinoprost tromethamine, 200IU of eCG, and 0.5mg of oestradiol cypionate IM. Embryos were transferred on Day 17. The overall P/ET was 42% (42/100). The P/ET for IVP embryos produced with semen from bulls B1, B12, B2, B3, and B4 was 3/15 (20%), 3/8 (37%), 23/42 (55%), 8/20 (40%), and 5/15 (33%), respectively. The P/ET was numerically greater for embryos produced using semen from the cloned bull (37%; B12) compared to embryos produced using semen from the original noncloned bull (20%; B1), although this difference was not statistically significant (P=0.62, Fisher’s exact test). There was a significant difference (P&lt;0.05) for the P/ET obtained with embryos produced using semen from bulls B1 and B2, but results for the other bulls were not significantly different. As far as we know, this is the first scientific report in Mexico concerning the use and comparison of semen from cloned and noncloned bulls for the production and transfer of bovine IVP embryos. In general, a wide numerical range of P/ET using the different bulls was observed (i.e. 20-55%). In this preliminary study, there was no impact of using frozen-thawed semen from a cloned bull for IVP on P/ET. The results from this research can contribute to the study and development of ART to improve P/ET obtained using Zebu IVP embryos. However, further research with a larger numbers of animals is required to confirm whether using semen from cloned and noncloned Bos indicus bulls for IVP impacts pregnancy success following embryo transfer.

Association of water quality with soil-transmitted helminthiasis and diarrhea in Nueva Santa Rosa, Guatemala, 2010

Improved water quality reduces diarrhea, but the impact of improved water quality on Ascaris and Trichuris, soil-transmitted helminths (STH) conveyed by the fecal-oral route, is less well described. To assess water quality associations with diarrhea and STH, we conducted a cross-sectional survey in households of south-eastern Guatemala. Diarrhea was self-reported in the past week and month. STH was diagnosed by stool testing using a fecal parasite concentrator method. We explored associations between Escherichia coli-positive source water (water quality) and disease outcomes using survey logistic regression models. Overall, 732 persons lived in 167 households where water was tested. Of these, 79.4% (581/732) had E. coli-positive water, 7.9% (58/732) had diarrhea within the week, 14.1% (103/732) had diarrhea within the month, and 6.6% (36/545) tested positive for Ascaris or Trichuris, including 1% (6/536) who also reported diarrhea. Univariable analysis found a statistically significant association between water quality and STH (odds ratio [OR] = 5.1, 95% confidence interval [CI] = 1.1-24.5) but no association between water quality and diarrhea. Waterborne transmission and effects of water treatment on STH prevalence should be investigated further. If a causal relationship is found, practices such as household water treatment including filtration might be useful adjuncts to sanitation, hygiene, and deworming in STH control programs.

Femtosecond laser writing of photonic devices in borate glasses compositionally designed to be laser writable

The design and performance of borate glass samples compositionally pre-designed to be femtosecond laser writable via laser-induced ion migration is reported in this Letter. It is demonstrated that borate glasses modified on purpose with small amounts of La₂O₃ and Na₂O can be straightforwardly used to produce high-index contrast (Δn) waveguides by femtosecond-laser-assisted ion migration. The positive Δn of the waveguides is caused by the local enrichment of La₂O₃ in the guiding region with a slope of 8·10^-3(mol.%)^-1. The value of this is consistent with numerical aperture measurements of the waveguides and local compositional measurements at the guiding region performed by energy-dispersive x-ray micro-analysis. The maximum achievable Δn values can be controlled through the initial La₂O₃ content of the glass. Maximum Δn values >10^-2 for samples with just 5.5 mol. % of La₂O₃ have been produced. This compositional design approach could be potentially used to produce highly efficient femtosecond laser writeable glasses in other glass families.

Estudio de una fitoalexina de <i>Borojoa cuatrecasas</i> (Rubiaceae)

Del fruto de Borojoa patinoi Cuatrecasas (Rubiaceae) se indujo y aisló una Fitoalexina que demostró propiedades antifúngicas contra el hongo Penicillium frequentans. Se propone una estructura para dicha Fitoalexina.

Pathological Findings in Wild Rats (Rattus rattus) Captured at Guafo Island, Northern Chilean Patagonia

The black rat (Rattus rattus) is an invasive species and potential reservoir of significant pathogens of man, domestic animals and wildlife. During the 2012-2014 austral summers, 201 black rats were captured and examined on the uninhabited Guafo Island, in Northern Chilean Patagonia (43.593029°S, 74.713481°W). The mite Ornithonyssus bacoti caused lymphoplasmacytic and eosinophilic dermatitis in all infected rats (105/210, 52%), but no skin lesions were observed in rats infected with Nosopsyllus spp. and Plocopsylla spp. fleas. Eighty-eight rats (44%) had mild lymphoplasmacytic and eosinophilic enterocolitis and 61 of these rats were infected with the nematode Heterakis spumosa. In the liver, 63 animals (31%) had areas of necrosis with histiocytic and eosinophilic inflammation associated with multiple Calodium hepaticum eggs, and in 15 cases there was co-infection with several Taenia taeniaeformis strobilocerci. Mild interstitial lymphoplasmacytic sialadenitis with intranuclear inclusion bodies, suggesting cytomegalovirus infection, was observed in 28 rats (15%). In the lung, alveolar histiocytosis (69 rats, 34%) and perivascular lymphocytic infiltrates (46 rats, 23%) were the most common findings. There was mild to moderate lymphoplasmacytic interstitial nephritis in 52 rats (26%) and in 15% of these cases Leptospira spp. antigen was detected in the distal renal tubules. Some of the diseases of black rats on Guafo Island are likely to play a role in rat population dynamics. The endemic Guafo Island long-clawed mole mouse (Geoxus lafkenche), sea lions and fur seals may be at risk for infection by some of these rat pathogens.

Isodesmic reaction for accurate theoretical pKa calculations of amino acids and peptides

Theoretical and quantitative prediction of pKa values at low computational cost is a current challenge in computational chemistry. We report that the isodesmic reaction scheme provides semi-quantitative predictions (i.e. mean absolute errors of 0.5-1.0 pKa unit) for the pKa1 (α-carboxyl), pKa2 (α-amino) and pKa3 (sidechain groups) of a broad set of amino acids and peptides. This method fills the gaps of thermodynamic cycles for the computational pKa calculation of molecules that are unstable in the gas phase or undergo proton transfer reactions or large conformational changes from solution to the gas phase. We also report the key criteria to choose a reference species to make accurate predictions. This method is computationally inexpensive and makes use of standard density functional theory (DFT) and continuum solvent models. It is also conceptually simple and easy to use for researchers not specialized in theoretical chemistry methods.

Formation mechanism of glyoxal-DNA adduct, a DNA cross-link precursor

DNA nucleobases undergo non-enzymatic glycation to nucleobase adducts which can play important roles in vivo. In this work, we conducted a comprehensive experimental and theoretical kinetic study of the mechanisms of formation of glyoxal-guanine adducts over a wide pH range in order to elucidate the molecular basis for the glycation process. Also, we performed molecular dynamics simulations to investigate how open or cyclic glyoxal-guanine adducts can cause structural changes in an oligonucleotide model. A thermodynamic study of other glycating agents including methylglyoxal, acrolein, crotonaldehyde, 4-hydroxynonenal and 3-deoxyglucosone revealed that, at neutral pH, cyclic adducts were more stable than open adducts; at basic pH, however, the open adducts of 3-deoxyglucosone, methylglyoxal and glyoxal were more stable than their cyclic counterparts. This result can be ascribed to the ability of the adducts to cross-link DNA. The new insights may contribute to improve our understanding of the connection between glycation and DNA cross-linking.

Effectiveness of Monovalent and Pentavalent Rotavirus Vaccines in Guatemala

BACKGROUND

Concerns remain about lower effectiveness and waning immunity of rotavirus vaccines in resource-poor populations. We assessed vaccine effectiveness against rotavirus in Guatemala, where both the monovalent (RV1; 2-dose series) and pentavalent (RV5; 3-dose series) vaccines were introduced in 2010.

METHODS

A case-control evaluation was conducted in 4 hospitals from January 2012 to August 2013. Vaccine status was compared between case patients (children with laboratory-confirmed rotavirus diarrhea) and 2 sets of controls: nondiarrhea "hospital" controls (matched by birth date and site) and nonrotavirus "test-negative" diarrhea controls (adjusted for age, birth month/year, and site). Vaccine effectiveness ([1 - odds ratio of vaccination] × 100%) was computed using logistic regression models.

RESULTS

We evaluated 213 case patients, 657 hospital controls, and 334 test-negative controls. Effectiveness of 2-3 doses of a rotavirus vaccine against rotavirus requiring emergency department visit or hospitalization was 74% (95% confidence interval [CI], 58%-84%) with hospital controls, and 52% (95% CI, 26%-69%) with test-negative controls. Using hospital controls, no significant difference in effectiveness was observed between infants 6-11 months (74% [95% CI, 18%-92%]) and children ≥12 months of age (71% [95% CI, 44%-85%]) (P= .85), nor between complete courses of RV1 (63% [95% CI, 23%-82%]) and RV5 (69% [95% CI, 29%-87%]) (P= .96). An uncommon G12P[8] strain, partially heterotypic to strains in both vaccines, was identified in 89% of cases.

CONCLUSIONS

RV1 and RV5 were similarly effective against severe rotavirus diarrhea caused by a heterotypic strain in Guatemala. This supports broader implementation of rotavirus vaccination in low-income countries where >90% global deaths from rotavirus occur.

Hookworm Infection in South American Fur Seal ( Arctocephalus australis) Pups

Tissues of South American fur seal pups naturally infected with hookworms ( Uncinaria sp) were examined. Hookworm infection was found in nearly all pups examined (132/140, 94%), and hookworm enteritis with secondary bacteremia was considered the cause of death in 46 (35%) pups. Common findings in these pups included severe hemorrhagic enteritis and numerous (mean intensity = 761.8) hookworms in the jejunum. Hookworms were recovered from the abdominal cavity in 12 of 55 pups (22%) examined through peritoneal wash; these pups had an average of 1343.3 intestinal hookworms and marked fibrinohemorrhagic peritonitis. In all pups that died as a consequence of hookworm infection, the intestinal villi were short, blunt, and fused, and there were variable numbers of free and intrahistiocytic gram-negative bacteria in submucosal hookworm feeding tracks, mesenteric lymph nodes, spleen, blood vessels, and liver sinusoids. Pups that died of causes unrelated to the hookworm infection (trauma) had hookworm feeding tracks confined to the apical portions of the mucosa, and moderate to marked catarrhal eosinophilic enteritis. The number of hookworms was negatively correlated with intestinal villous length and number of leukocytes in the intestine. Pups with hookworm peritoneal penetration had nematodes with little or no blood in the hookworm intestine, suggesting that lack of food for the nematode could be associated with peritoneal penetration. Findings suggest that the initial burden of larval infection, the level of the host tissue response, or a combination determine the number of nematodes in the intestine, the severity of hookworm tissue damage, and pup mortality.

Hemangiomatosis Associated with Osteolysis of the Mandible in a Dog Resembling Gorham-Stout Disease in Humans

A 6-month-old female German Shepherd Dog died as a result of profuse oral bleeding. At postmortem examination, the oral cavity showed visible roots of the right mandibular fourth premolar and first molar teeth and, in addition, they were very mobile and compressible. Radiographs showed a generalized radiolucency in the body of the right mandible, with evidence of resorption of the affected alveolar bone. Histologically, the lesion of the right mandible was characterized by the lysis of bony structures and a non-malignant proliferation of blood-filled vascular spaces lined by a single layer of well-differentiated endothelial cells. The clinical, radiographic, and histologic presentation of this dog is consistent with that associated with Gorham-Stout disease, a rare bone disorder in humans.

Feasibility of tuberculosis treatment monitoring by video directly observed therapy: a binational pilot study

BACKGROUND

Although directly observed therapy (DOT) is recommended worldwide for monitoring anti-tuberculosis treatment, transportation and personnel requirements limit its use.

OBJECTIVE

To evaluate the feasibility and acceptability of 'video DOT' (VDOT), which allows patients to record and transmit medication ingestion via videos watched remotely by health care providers to document adherence.

METHODS

We conducted a single-arm trial among tuberculosis (TB) patients in San Diego, California, USA, (n = 43) and Tijuana, Mexico (n = 9) to represent high- and low-resource settings. Pre-/post-treatment interviews assessed participant characteristics and experiences. Adherence was defined as the proportion of observed doses to expected doses.

RESULTS

The mean age was 37 years (range 18-86), 50% were male, and 88% were non-Caucasian. The mean duration of VDOT use was 5.5 months (range 1-11). Adherence was similar in San Diego (93%) and Tijuana (96%). Compared to time on in-person DOT, 92% preferred VDOT, 81% thought VDOT was more confidential, 89% never/rarely had problems recording videos, and 100% would recommend VDOT to others. Seven (13%) participants were returned to in-person DOT and six (12%) additional participants had their phones lost, broken or stolen.

CONCLUSIONS

VDOT was feasible and acceptable, with high adherence in both high- and low-resource settings. Efficacy and cost-effectiveness studies are needed.

Population Density, Poor Sanitation, and Enteric Infections in Nueva Santa Rosa, Guatemala

Poor sanitation could pose greater risk for enteric pathogen transmission at higher human population densities because of greater potential for pathogens to infect new hosts through environmentally mediated and person-to-person transmission. We hypothesized that incidence and prevalence of diarrhea, enteric protozoans, and soil-transmitted helminth infections would be higher in high-population-density areas compared with low-population-density areas, and that poor sanitation would pose greater risk for these enteric infections at high density compared with low density. We tested our hypotheses using 6 years of clinic-based diarrhea surveillance (2007–2013) including 4,360 geolocated diarrhea cases tested for 13 pathogens and a 2010 cross-sectional survey that measured environmental exposures from 204 households (920 people) and tested 701 stool specimens for enteric parasites. We found that population density was not a key determinant of enteric infection nor a strong effect modifier of risk posed by poor household sanitation in this setting.

Salmonella on Raw Poultry in Retail Markets in Guatemala: Levels, Antibiotic Susceptibility, and Serovar Distribution

The objective of this study was to determine Salmonella numbers on retail raw chicken carcasses in Guatemala and to phenotypically characterize the isolates (serotyping and antibiotic susceptibility). In total, 300 chicken carcasses were collected from seven departments in Guatemala. Salmonella numbers were determined using the most-probable-number method following the U. S. Department of Agriculture's Food Safety and Inspection Service protocol. In total, 103 isolates were obtained, all of which were tested for antibiotic susceptibility, whereas 46 isolates were serotyped. Overall, Salmonella prevalence and mean number (mean log most probable number per carcass) was 34.3% and 2.3 (95% confidence interval: 2.1 to 2.5), respectively. Significant differences (P < 0.05) in Salmonella prevalence were found by storage condition (refrigerated or ambient temperature), market type (wet markets, supermarkets, and independent poultry stores), chicken production system (integrated or nonintegrated production company), and chicken skin color (white or yellow). Chickens produced by integrated companies had lower Salmonella numbers (P < 0.05) than nonintegrated companies, and white-skin carcasses had lower numbers (P < 0.05) than yellow-skin carcasses. Among 13 different Salmonella serovars identified, Paratyphi B (34.8%) was most prevalent, followed by Heidelberg (16.3%) and Derby (11.6%). Of all the Salmonella isolates, 59.2% were resistant to one to three antibiotics and 13.6% to four or more antibiotics. Among all the serovars obtained, Salmonella Paratyphi B and Heidelberg were the most resistant to the antibiotics tested. Salmonella levels and antibiotic resistant profiles among isolates from raw poultry at the retail market level were high relative to other reports from North and South America. These data can be used by Guatemalan stakeholders to develop risk assessment models and support further research opportunities to control transmission of Salmonella spp. and antibiotic-resistant isolates from chicken meat to humans.

A DFT study of the carboxymethyl-phosphatidylethanolamine formation from glyoxal and phosphatidylethanolamine surface. Comparison with the formation of N(ε)-(carboxymethyl)lysine from glyoxal and l-lysine

Mechanisms of the generation of CML and CM-PE from the reactions between glyoxal and l-lysine, and glyoxal and phosphatidylethanolamine (PE) were studied using the DFT method.

Respiratory syncytial virus infection in Guatemala, 2007-2012

BACKGROUND

Respiratory syncytial virus (RSV) is a major cause of acute respiratory illness (ARI). Little is known about RSV disease among older children and adults in Central America.

METHODS

Prospective surveillance for ARI among hospital patients and clinic patients was conducted in Guatemala during 2007-2012. Nasopharyngeal and oropharyngeal swab specimens were tested for RSV, using real-time reverse-transcription polymerase chain reaction.

RESULTS

Of 6287 hospitalizations and 2565 clinic visits for ARI, 24% and 12%, respectively, yielded RSV-positive test results. The incidence of RSV-positive hospitalization for ARI was 5.8 cases/10 000 persons per year and was highest among infants aged <6 months (208 cases/10 000 persons per year); among adults, the greatest incidence was observed among those aged ≥ 65 years (2.9 cases/10 000 persons per year). The incidence of RSV-positive clinic visitation for ARI was 32 cases/10 000 persons per year and was highest among infants aged 6-23 months (186 cases/10 000 persons per year). Among RSV-positive hospital patients with ARI, underlying cardiovascular disease was associated with death, moribund discharge, intensive care unit admission, or mechanical ventilation (odds ratio, 4.1; 95% confidence interval, 1.9-8.8). The case-fatality proportion among RSV-positive hospital patients with ARI was higher for those aged ≥ 5 years than for those aged <5 years (13% vs 3%; P < .001).

CONCLUSIONS

The incidences of RSV-associated hospitalization and clinic visitation for ARI were highest among young children, but a substantial burden of ARI due to RSV was observed among older children and adults.

Stability of Schiff bases of amino acids and pyridoxal-5'-phosphate

Stability of Schiff bases from Pyridoxal-5'-phosphate andα- and nonα-amino acids and amines have been studied in a wide range of pH. Furthermore the transamination process for the PLP-serine Schiff base and the cyclization reaction of PLP-histidine Schiff base have also been studied.Results show that theα-position on carboxyl group of amino acids plays an important role on the mechanism of hydrolysis of imine bond. Absence of ionic groups in the surroundings of that bond seems to be an important fact of stability.In the transamination reaction, the rate-determining step is the isomerization of the Schiff base to ketoimine, since the rate constants for disappearance of Schiff base coincide with the rate constants for PMP formation. This process is catalyzed by the OH(-)/H2O system and the monoprotonated amino acid.

[Are domiciliary care patients receiving adequate thromboprophylaxis?]

INTRODUCTION

The study aims to determine the percentage of patients treated at home with an indication of prophylaxis of thromboembolic disease (TED) according to the PRETEMED guidelines and whether they receive such prophylaxis.

MATERIALS AND METHODS

A cross-sectional descriptive study was conducted in Segovia Palace Health Centre (Madrid).

INCLUSION CRITERIA

to be included in the domiciliary care protocol.

EXCLUSION CRITERIA

terminal patient, hospitalised or surgery in the last 3 months. The variables used include, age, sex, duration of domiciliary care, mobility, anticoagulant or antiplatelet treatment and reason, and associated and precipitating factors to calculate the risk of TED according to the PRETEMED guidelines, and if they receive such prophylaxis, by reviewing computerised medical records and meeting with the staff responsible.

RESULTS

The study included a total of 187 patients, of whom 81% were women There was a significant differences in mean age by sex (men, 76.91 years, 95% CI; 72.59-81.24, and women, 86.72 years, 95% CI; 72.59-81.24, P<.05). Almost two-thirds (65%) walked in the home. There were 3.7% patients who had an indication for receiving prophylaxis, but did not receive it, although 85.8% of them were on anticoagulants or antiplatelet therapy for other reasons.

CONCLUSIONS

Most patients in domiciliary care have a low baseline risk of developing a TED episode in our study. There should be more emphasis placed on the prophylaxis of TED in acute medical episodes in which patients with slightly elevated risk may increase the likelihood of TED. Observational studies should be conducted to study the baseline risk and the subsequent development of TED in the population receiving home care.

A new kidney allocation policy in Chile: computer-based simulations

INTRODUCTION

Kidney allocation should reach a balance between equity and efficiency. In Chile kidneys are allocated based on ABO matching, first to medical priorities and then according to a point scheme considering human leukocyte antigen (HLA) match (60%), waiting list time (20%), and panel-reactive antibodies (PRA; 20%); pediatric recipients receive extra points. A new policy maintains ABO matching and medical priorities as the first step, but incorporates other successive steps: previous living donors donors, 0 mismatch, pediatric recipients, and finally all other recipients according to a point scheme incorporating recipient age, HLA match, PRA, and time on waiting list with similar proportions. We compared the resulting transplantations using the new versus the older allocation policy.

METHODS

We analyzed computer-generated simulations using actual patients (N = 1176) on the Chilean waiting list in 2011 with the 300 donors over the previous 3 years.

RESULTS

The new policy a significantly decreased recipient age from 43 ± 0.3 years to 41 ± 0.3 and increased the number of 0-mismatched transplantations from 3% to 4%. The mean HLA mismatch increased from 2.8 ± 0.1 to 3.6 ± 0.1. Waiting time increased from a mean of 38 ± 1 months to 40 ± 1 months, but patients remaining on the waiting list had less waiting time with the new rule.

CONCLUSIONS

With the proposed changes younger patients are being privileged and the importance of compatibility is diminished (except for 0-mismatched transplantations). The chance of a good match is directly related to the size of the recipient pool, thus an allocation policy that privileges HLA matching in a restricted recipient pool is especially unfavorable for younger patients. Including age of the recipient as a continuum can help to compensate for this lack of equity. Computer-generated simulations can help discern which policies are best suited for each country based on their local characteristics.

Biliary complications in orthotopic liver transplantation using choledochocholedochostomy with a T-tube

Despite significant advances in orthotopic liver transplantation (OLT), biliary tract reconstruction is still a major source of complications. Choledochocholedochostomy with a T-tube used to be the standard procedure for biliary reconstruction after OLT. However, many centers currently avoid use of the T-tube because of the high incidence of complications. Our aim was to study the biliary complications occurring at our center when end-to-end choledochocholedochostomy (EE-CC) over a T-tube was used as the standard procedure for biliary reconstruction. A retrospective review was conducted of all patients who underwent liver transplantation from February 1, 1996, to April 30, 2010. Only patients requiring any therapy to treat biliary complications were considered, whereas those with concomitant hepatic artery complications were excluded. The study cohort consisted of 743 patients who had EE-CC with a T-tube. Of these, 73 patients (9.8%) experienced any biliary complication. Anastomotic strictures occurred in 17 patients (2.3%), and non-anastomotic strictures in 2 (0.3%). Fifteen patients with anastomotic strictures were successfully treated by dilatation and stenting. Bile leakage was diagnosed in 39 patients (5.2%). Leakage occurred at the anastomosis in 15 patients (2%), and at the exit site of the T-tube in 24 patients (3.2%). Tube opening was the only treatment used in 30 patients with bile leakage (76.9%). Seven patients experienced leaks after elective T-tube removal (1%). Overall, repeat surgery to manage biliary complications was needed in 9 patients (1.2%). The mortality rate from biliary complications was 0.13%. In conclusion, EE-CC with a T-tube was followed by a low incidence of biliary complications. The complication rate after elective T-tube removal and the repeat surgery rate were extremely low. These results might challenge the current trend to avoid T-tube stenting in OLT.

Long-term durability of response to adalimumab in Crohn's disease

BACKGROUND

Adalimumab is an effective treatment for Crohn's disease (CD), but may also be associated with loss of response. Few reports provide insight into the durability of treatment of CD with adalimumab for periods longer than 12 months in clinical practice.

AIMS

To evaluate the long-term durability of adalimumab maintenance treatment and to identify predictive factors associated with loss of response.

METHODS

CD patients who initially responded to adalimumab were evaluated in a historical cohort study. Maintenance of long-term response was estimated using Kaplan-Meier analysis. Cox regression analysis was performed to identify potential predictive factors for loss of efficacy.

RESULTS

In all, 380 CD patients were included (mean age, 38 years; 52% female). Of these, 43% had ileocolic CD, 50% inflammatory CD, and 41% perianal CD. Median follow-up with adalimumab was 8 months (range, 4-75 months). The annual risk of loss of response to adalimumab was 18% per patient-year of follow-up. Twenty-eight percent of patients were anti-TNF-naïve and 72% anti-TNF-experienced. The loss of efficacy was 8% per patient-year of follow-up in the anti-TNF-naïve patients and 22% in the anti-TNF-experienced group (P < 0.01). In the multivariate analysis, the presence of extraintestinal manifestations (hazard ratio [HR] = 1.7; 95% confidence interval [CI] = 1.02-2.9) and previous experience with other anti-TNF agents (HR = 2.5,95% CI = 1.2-5.3) were associated with higher risk of loss of efficacy.

CONCLUSIONS

A relevant proportion of CD patients on long-term adalimumab lost response. The risk of loss of response was higher (more than 2-fold) in anti-TNF-experienced than in anti-TNF-naïve patients (22% vs. 8% per patient-year of treatment). Having extraintestinal manifestations seems to increase the risk of loss of efficacy.

High- and low-spin Fe(III) complexes of various AGE inhibitors

Density functional theory calculations [CPCM/UM06/6-31+G(d,p)] were used to elucidate the structures and relative stability of Fe(III) complexes with various ligands that inhibit the formation of advanced glycation end products (AGEs) or iron overloaded disease (viz. aminoguanidine, pyridoxamine, LR-74, Amadori compounds, and ascorbic acid). EDTA was used as the free energy reference ligand. The distorted neutral octahedral complex containing one iron atom and three molecules of pyridoxamine [Fe(PM)(3)] was found to be the most stable. The stability of the complexes decreases in the following chelate sequence: pyridoxamine, Amadori complex, aminoguanidine, LR inhibitor, and ascorbic acid.

Infliximab salvage therapy after failure of ciclosporin in corticosteroid-refractory ulcerative colitis: a multicentre study

BACKGROUND

Ciclosporin has proven to be effective in patients with corticosteroid-refractory ulcerative colitis (UC). When therapy with this drug fails, infliximab can be considered to avoid colectomy. The efficacy and safety of this sequential approach remain unknown.

AIM

To assess the efficacy and safety profile of treatment with infliximab after failure of ciclosporin in patients with a corticosteroid-refractory flare of UC.

METHODS

Retrospective review of medical records of patients with a corticosteroid-refractory flare of UC who did not respond to ciclosporin and received salvage therapy with infliximab within a month of discontinuing ciclosporin. The severity of the flare and response to the treatment were graded using the Lichtiger index. Cumulative rates of colectomy were calculated using Kaplan-Meier analysis. Cox regression analysis was performed to identify predictors of colectomy. To evaluate the safety profile of this treatment strategy, any adverse event occurring after the first infusion of infliximab was considered.

RESULTS

The study population comprised 47 patients with corticosteroid-refractory UC treated with infliximab after failure of ciclosporin. The median baseline Lichtiger index was 13. The mean time from the last ciclosporin dose to the first infliximab infusion was 6 days. After the first infliximab infusion, 13% of patients achieved remission, and 74% partial response. Of the 35 patients who received the third infliximab infusion, 60% achieved remission, and 37% partial response. Fourteen patients (30%) underwent colectomy. The rate of adverse events was 23%. One death occurred in a 40-year-old man who failed ciclosporin and infliximab and underwent surgery 10 days after the first infliximab infusion; he died of nosocomial pneumonia.

CONCLUSIONS

Treatment with infliximab makes it possible to avoid colectomy in two-thirds of corticosteroid-refractory UC patients in whom ciclosporin fails. However, the rates of adverse events and mortality mean that the decision to administer sequential therapy (ciclosporin-infliximab) should be taken on an individual basis.

[A retrospective study about 11 cases of Esthesioneuroblastomas treated in Hospital Santa Creu i Sant Pau between 2000 and 2008 and literature review]

INTRODUCTION. Esthesioneuroblastoma (ENB) is a very uncommon malignant tumor with a neuroectodermal origin that usually involves the anterior cranial fossa and nasal cavity. OBJECTIVES. To review our experience in the management of ENB and assess the validity of the histopathological diagnosis, modality of treatment and prognostic factors of the disease comparing our findings with the literature. METHODS. A retrospective study of 11 cases with the diagnosis of esthesioneuroblastoma treated in our hospital between 2000 and 2008. Statistical analysis was performed in search for prognostic factors. The bibliography about ENB published between 1990 and 2009 was reviewed RESULTS. There were 3 women and 8 men, with a mean age of 42 years old (range 20-71y). Their symptoms upon admission were nasal obstruction (81%), epistaxis (27%), visual loss (18%), headache and others. According to the Kadish Stage, 2 were stage B and 9 were stage C. Dulguerov and Calcaterra Classification was also used: 2 were T2, 3 were T3 and 6 were T4. The hystopathological result according to the Hyams classification was: 2 cases in stage I, 4 in stage II, 3 in stage III and 2 in stage IV. The two cases classified in stage IV changed the diagnosis to undifferenciate tumor in the second biopsy. A subcranial approach was performed in 8 cases combined with endonasal endoscopy to confirm the total removal, followed by radiotherapy in all and chemotherapy in one case, resulting on 62% (5 patients) being alive without disease, 12,5% (1 p) alive with disease, and 25% (2 p) dead of disease. Another patient was operated by a single endonasal endoscopic approach and a subtotal removal was achieved. This patient is alive without disease. The other 2 patients were treated by biopsy plus radiotherapy and chemotherapy, because they were considered unresectable, and one of them is alive with disease and the other one is dead of disease. Radiotherapy was performed in all cases and chemotherapy in 5 cases. The hystopathological grading system of Hyams was considered statistically significant as a prognostic factor of disease-free survival. CONCLUSIONS. When the hystopathological diagnosis of ENB is considered, the Hyams classification can be valid considering grade IV as an advanced stage that is sometimes difficult to differentiate from other undiferentiated tumors. The subcranial approach or craneofacial resection in advanced stages (Kadish C and some B) should be considered as the first treatment of choice. Radiotherapy is indicated in all cases and chemotherapy in selected cases. Hyams' classification was the only staging system that proved useful as a prognostic factor in our series.

Periodontal regeneration following implantation of cementum and periodontal ligament-derived cells

BACKGROUND AND OBJECTIVE

The periodontal regeneration of bone defects is often unsatisfactory and could be largely improved by cell therapy. Therefore, the purpose of this study was to evaluate the regenerative potential of implanting canine cementum-derived cells (CDCs) and canine periodontal ligament-derived cells (PDLDCs) in experimentally created periodontal intrabony defects in beagle dogs.

MATERIAL AND METHODS

Cells were obtained from premolars extracted from four beagle dogs. Three-wall intrabony periodontal defects, 3 mm wide and 4 mm deep, were surgically created in their second and fourth premolars and plaque was allowed to accumulate. Once the defects were surgically debrided, periodontal regeneration was attempted by random implantation of collagen sponges embedded with 750,000 CDCs, 750,000 PDLDCs or culture medium. After 3 mo of healing, specimens were obtained and periodontal regenerative outcomes were assessed histologically and histometrically.

RESULTS

The histological analysis showed that a minimal amount of new cementum was formed in the control group (1.56 ± 0.39 mm), whereas in both test groups, significantly higher amounts of new cementum were formed (3.98 ± 0.59 mm in the CDC group and 4.07 ± 0.97 mm in the PDLDC group). The test groups also demonstrated a larger dimension of new connective tissue, resulting in a significantly more coronal level of histological attachment.

CONCLUSION

This proof-of-principle study suggests that cellular therapy, in combination with a collagen sponge, promoted periodontal regeneration in experimental intrabony periodontal defects.