Percutaneous transhepatic cholangioscopy for benign and malignant biliary disease using a novel short single-operator cholangioscope

BACKGROUND

The length of conventional single-use cholangioscopes poses a challenge for percutaneous or laparoscopic approaches for direct visualization of the biliary tract. The aim of this retrospective observational clinical study was to assess the use of a dedicated percutaneous short single-operator cholangioscope (PSSOC) for diagnosis and treatment of benign or malignant biliary diseases.

METHODS

Retrospective analysis of a prospectively maintained database including all consecutive patients undergoing percutaneous transhepatic cholangioscopy with the PSSOC between 06/2021 and 01/2023.

RESULTS

Forty patients were included (22F/18 M, age 58.7 ± 16.7 years). The diagnostic and therapeutic management plan was based on procedural findings. Indications were bile duct obstruction associated with complex anatomy (n = 13), choledocholithiasis (n = 11), suspected malignant stenosis of the biliary tract (n = 11), biliary stent placement (n = 2) and removal (n = 1), and failed endoscopic retrograde cholangiopancreatography (n = 2). The cholangioscopies were diagnostic (n = 5), therapeutic (n = 20) or both simultaneously (n = 15). The most frequent procedures were electrohydraulic lithotripsy (n = 25) and biopsy sampling (n = 12). Complications occurred in 7 cases (17.5%), including cholangitis (n = 4, B2), pleural perforation (n = 1, B2), portal bleeding (n = 1, B3), and Tako-Tsubo syndrome (n = 1, B3), classified according to the Society of Interventional Radiology classification. Intraprocedural visual diagnosis was confirmed by the histopathologic result in 11/12 patients in which biopsies were performed (91.7%). PSSOC was relevant to avoid surgery in 2 patients (5%) with indeterminate strictures, allowing to rule out malignancy and treat the lithiasis.

CONCLUSIONS

Direct visualization of the biliary tract enabled targeted biopsies for histopathological diagnosis. The visual and histopathological diagnoses were concordant in all but one case. Percutaneous cholangioscopy with a dedicated PSSOC allows to optimize identification and treatment of complex biliary disease including biliary lithiasis while assessing bile duct patency. The clinical use of the novel PSSOC system was safe and effective and could prevent surgical exploration in select patients.

Causes of revisional surgery, reoperations, and readmissions after bariatric surgery

INTRODUCTION AND OBJECTIVES

Bariatric surgery is the most effective treatment for weight loss, with comorbidity control. With low complication rates, the reasons for reoperation are major complications or weight loss failure/weight regain. Nonsurgical problems can also present, such as anemia, dehydration, chronic pain, and malnutrition, among others. Our aim was to analyze the main causes of revisional surgery, reoperation, and hospital readmission, at a specialized bariatric center.

METHODS

A retrospective study was conducted on patients that underwent bariatric surgery within the time frame of 2012 and 2019. The baseline analysis included demographic, anthropometric, and perioperative data, as well as a sub-analysis of the main readmission causes and complications.

RESULTS

A total of 776 primary surgeries were performed (649 RYGBP, 127 SG, and 10 revisional surgeries), and 99 patients were identified for the study: 10 revisional surgeries, 44 reoperations, and 45 readmissions. The incidence of revisional surgery was 1.2%, reoperation was 5.6%, and readmission 5.8%. Fifty percent of the revisional surgeries were performed due to insufficient weight loss or weight regain; the most frequent causes of reoperation were cholecystitis (38.6%) and internal hernias (9.1%); and the most common causes of readmission were nonspecific abdominal pain (35.5%) and dehydration (24.4%).

CONCLUSION

The most frequent causes of postoperative readmission were nonsurgical events, followed by non-bariatric reoperations, and finally revisional surgeries. There was a low incidence of early reoperations. Knowledge of the abovementioned data is important for identifying higher-risk patients, to prevent major complications.

The genus Gautieria (Gomphales) in Europe and the Mediterranean Basin: a morphological and phylogenetic taxonomic revision

Type material and additional collections of 11 taxa of Gautieria described in Europe and North Africa have been studied, namely G. dubia, G. graveolens, G. morchelliformis var. globispora, G. morchelliformis var. magnicellaris, G. morchelliformis var. morchelliformis, G. morchelliformis var. stenospora, G. otthii, G. pseudovestita, G. retirugosa, G. trabutii and G. villosa. At the same time, morphological and genetic studies on recent and herbarium collections from several European countries have been carried out. This enabled clarification of sections within Gautieria and differentiation of 28 taxa, of which 21 are new to science. However, the deeper relationships and nomenclature changes related to the phylogenetic position of the genus Gautieria within Gomphaceae will not be addressed in this study because they would require a more complete molecular analysis together with that of related genera, e.g., Gomphus, Turbinellus, and the four subgenera of Ramaria. In addition, a lectotype for G. villosa var. villosa and reference specimens for G. graveolens and G. morchelliformis var. morchelliformis are selected, and the new combination G. morchelliformis var. dubia is proposed. Detailed descriptions, macro- and microphotographs and distribution maps of all taxa are provided, as well as extensive information on their ecology, chorology and phylogeny. A key is included to facilitate identification of taxa. Citation: Vidal JM, Cseh P, Merényi Z, et al. 2023. The genus Gautieria (Gomphales) in Europe and the Mediterranean Basin: a morphological and phylogenetic taxonomic revision. Persoonia 50: 48 -122. https://doi.org/10.3767/persoonia.2023.50.03.

Immunization with thiol-binding proteins from Haemonchus contortus adult worms partially protects goats against infection during prepatency

To contribute of the knowledge of the immune mechanisms underlying the response to the immunization of goats with thiol-binding proteins fractions (PBS-TSBP) from Haemonchus contortus (H. contortus) adult worms, this study analyzed the degree of protection and the immune responses developed against the parasite after vaccination with this antigenic complex during the time-elapsing between challenge with L3 of the parasite and the development of adult worms, evidenced by the appearance of first faecal eggs (prepatent period or prepatency). Goat kids immunized with PBS-TBSP generated an immune response during the prepatency which translates into a reduction in the number of worms, as well as a lower reduction on packed cell volume and plasma protein levels in relation to the non-vaccinated animals. As previously described in other studies carried out after the prepatent period, this protection was associated with a systemic humoral response. At the local level, a specific humoral response was also observed, together with an immune-inflammatory infiltrate in the gastric mucosa of MCH-II + cells and CD4⁺ lymphocytes, whose number was associated with a reduction in the number of worms and an increase in plasma proteins. A high peripheral eosinophilia was detected, but no corresponding increased infiltration of the gastric mucosa by eosinophils or globular leukocytes was observed. In agreement with previous data on the immunolocalization of the antigens used here, the results obtained contribute to the idea that these may be excretion/secretion (E/S) products necessary for parasite survival, whose inactivation during the larval and/or pre-adult stages may have contributed to immunoprotection.

Trace classical conditioning impairment after lesion of the lateral part of the goldfish telencephalic pallium suggests a long ancestry of the episodic memory function of the vertebrate hippocampus

There is an ongoing debate on the evolutionary origin of the episodic memory function of the hippocampus. A widely accepted hypothesis claims that the hippocampus first evolved as a dedicated system for spatial navigation in ancestral vertebrates, being transformed later in phylogeny to support a broader role in episodic memory with the emergence of mammals. On the contrary, an alternative hypothesis holds that the hippocampus of ancestral vertebrates originally encoded both the spatial and temporal dimensions of relational memories since its evolutionary appearance, thus suggesting that the episodic-like memory function of the hippocampus could be the primitive condition in vertebrate forebrain evolution. The present experiment was aimed at scrutinizing these opposing hypotheses by investigating whether the hippocampal pallium of teleost fish, a vertebrate group that shares with mammals a common ancestor that lived about 400 Mya, is, like the hippocampus of mammals, essential to associate time-discontiguous events. Thus, goldfish with lesions in the ventral part of the dorsolateral pallium (Dlv), a telencephalic region considered homologous to the hippocampal pallium of land vertebrates, were trained in trace versus delay eyeblink-like classical conditioning, two learning procedures that differ only in the temporal relationships between the stimuli to be associated in memory. The results showed that hippocampal pallium lesion in goldfish severely impairs trace conditioning, but spares delay conditioning. This finding challenges the idea that navigation preceded relational memory in evolutionary appearance and suggests the possibility that a relational memory function that associates the experienced events in both the spatial and temporal dimensions could be a primitive feature of the hippocampus that pre-existed in the common ancestor of vertebrates.

Spectroscopy of the frustrated quantum antiferromagnet Cs2CuCl4

We investigate the electronic structure of Cs₂CuCl₄, a material discussed in the framework of a frustrated quantum antiferromagnet, by means of resonant inelastic x-ray scattering (RIXS) and density functional theory (DFT). From the non-dispersive highly localizedddexcitations, we resolve the crystal field splitting of the Cu²⁺ions in a strongly distorted tetrahedral coordination. This allows us to model the RIXS spectrum within the crystal field theory (CFT), assign theddorbital excitations and retrieve experimentally the values of the crystal field splitting parametersD_q,D_sandD_τ. The electronic structure obtainedab-initioagrees with the RIXS spectrum and modelled by CFT, highlighting the potential of combined spectroscopic, cluster and DFT calculations to determine the electronic ground state of complex materials.

P–637 Development and validation of an Artificial Intelligence algorithm that matches a clinician ability to select the best follitropin dose for ovarian stimulation

Study question

Is it possible for an Artificial Intelligence (AI) model to match the performance of clinicians in prescribing the first dose of follitropin?

Summary answer

The AI based Decision Support System (DSS) we developed identifies accurately the optimal starting dose range of follitropin and prospectively matches the clinicians’ performance.

What is known already

Most patients treated by IVF undergo Controlled Ovarian Stimulation (COS). Based on their ovarian markers, demographic characteristics, and clinical history, an initial dose of follitropin is prescribed. Failing to tailor correctly this dose can result in a suboptimal ovarian response, leading on the one hand to low and ineffective response or, on the other, to excessive and dangerous stimulation. AI methods can learn from large databases of COS results and generate predictive models to assist the clinicians in optimizing this decision.

Study design, size, duration

A database of 2713 first IVF cycles from 5 clinics, from 2011 to 2019 was used to develop the model. Predictor variables included: age, BMI, AMH, FSH, LH, estradiol, Antral Follicular Count (AFC), infertility etiology, and previous live births. 80% of the database was used to train the algorithm, and 20% to test the DSS. Additional 524 cycles from a different period (2020–2021) were used for prospective validation.

Participants/materials, setting, methods

Follitropin dosage was divided in 4 categories: 100–150IU, 151–200IU, 201–250IU, and >250IU. An optimal ovarian response is defined as retrieving 10–15 MII, whenever the patient ovarian reserve allows it. To predict the optimal dose range personalized to each patient, the DSS uses a Random Forest model learned with training cycles. To evaluate the DSS performance, a score for each dose range and each patient was defined given the prescribed doses and the corresponding ovarian responses.

Main results and the role of chance

The cycles included in the database were from women 37.2±4.9 years old [18–45], with a BMI of 23.7±4.2, AMH of 2.4±2.3, AFC of 11.8±7.7; the average number of oocytes and MII obtained was 10.1±7.1 and 7.2±5.3, respectively. The DSS achieved a performance mean score of 0.88 in the testing database, a value significantly better than the one calculated for the doses prescribed by the clinicians, which had a mean score of 0.83 (p-value <0.05). In the validation database the mean performance score of the DSS recommendations was 0.87, and there were no significant differences with the score of the doses actually prescribed by clinicians, also with a score of 0.86. With these results the model was shown to at least match the performance of the human doctor. It is worthy of note that the performance score value for the doses prescribed by clinicians in the validation database is relevantly higher than in the test database, closing the gap previously existing with the DSS performance. As the validation cycles are separated temporally from the rest of the cases and correspond to the newer ones, it is plausible to infer that a more experienced clinical staff would perform better.

Limitations, reasons for caution

The DSS prospective validation should be extended to more clinical cases to ensure higher reliability. Hyper-responders were underrepresented in the database which can lead to less accurate recommendation in some of these women. As all AI models, the DSS should be tested prospectively before clinical application.

Wider implications of the findings: The AI based clinical Decision Support System that we developed could be deployed as a training and learning tool for new clinicians and serve as quality control for experienced ones; further, it can be used as an electronic second opinion, for instance by providing information in peer-to-peer case discussions.

Trial registration number

Not applicable

Clinical trial to assess tolerability and subrogate efficacy effects of an abbreviated schedule with house dust mites mixture subcutaneous immunotherapy

Summary

Objective. To evaluate the tolerability and efficacy of Dermatophagoides pteronyssinus/Dermatophagoides farinae mixture subcutaneous immunotherapy (SCIT). Methods. Patients received an abbreviated build-up schedule. The aims were: number, percentage, and severity of adverse reactions. Secondary outcomes included: changes in immunoglobulin titers and changes in dose-response skin prick tests. Results. Out of 289 administrations, 17% elicited any clinically relevant adverse reaction. Most of them were local reactions (LR) (9.4%) and the rest (7.6%) were systemic. Significant increases in sIgG and sIgG4 were detected in serum samples. Cutaneous reactivity decreased significantly. Conclusions. SCIT with house dust mites mixture of ROXALL Medicina España S.A. seems to have an acceptable tolerability profile, induces blocking IgG and decreases skin reactivity.

Multiobjective control architecture to estimate optimal set points for user comfort and energy saving in buildings

Temperature control in buildings is usually driven by energy conservation although the occupants' comfort is also important considering its impact on productivity and health. However, energy efficiency and comfort are opposing objectives and therefore this type of problem can be resolved by means of a multiobjective optimization approach. The simulations we carried out indicate that set points optimization has the potential to reduce energy consumption in the order of 10% while also providing a comfortable work environment for the occupants.

Economic evaluation of sunitinib versus pazopanib and best supportive care for the treatment of metastatic renal cell carcinoma in Chile: cost-effectiveness analysis and a mixed treatment comparison

Background: Sunitinib and Pazopanib are two metastatic renal cell carcinoma (MRCC) treatment alternatives, however the health system in Chile does not consider coverage for any. The cost-effectiveness versus relevant comparator was assessed to support evidence-based decision making. Methods: A four health states Markov model was built: first, second line treatments, BSC and death. Benefits were measured in QALYs, and efficacy estimates were obtained from an indirect treatment comparison. A 10-year time horizon and a 3% undifferentiated discount rate were considered. Deterministic and probabilistic sensitivity analyses were performed. Results: The costs of treating MRCC with Sunitinib were higher than Pazopanib and BSC. When comparing Sunitinib versus Pazopanib, the incremental benefit is small favoring Sunitinib (0.03 QALYs). The base case scenario shows an average ICER of PA versus BSC of US$62,327.11/QALY and of US$85,885/QALY for Sunitinib versus Pazopanib. The ICER was most sensitive to the OS relative to BSC, where evidence was associated to important bias. Conclusions: Sunitinib or Pazopanib can be considered cost-effective if a 3 GDP per-capita threshold is assumed. The decision between SU or PA is highly sensitive to the price of the drugs, rather than the outcomes. Therefore, the decision might be made based on cost-minimization exercise.

Copy number variants of Ras/MAPK pathway genes in patients with isolated cryptorchidism

Cryptorchidism is the most common congenital disorder in boys, but the cause for most cases remains unknown. Patients with Noonan Syndrome are characterized by a typical face, growth retardation, congenital heart defects, learning disabilities and cryptorchidism. Copy number variations of Ras/MAPK pathway genes are unusual in patients with several clinical features of Noonan Syndrome; however, they have not been studied in patients with only one feature of this condition, such as cryptorchidism. Our aim was to determine whether patients with isolated cryptorchidism exhibit Ras/MAPK pathway gene copy number variations (CNVs). Fifty-nine patients with isolated cryptorchidism and negative for mutations in genes associated with Noonan Syndrome were recruited. Determination of Ras/MAPK pathway gene CNVs was performed by Comparative Genome Hybridization array. A CNV was identified in two individuals, a ~175 kb microduplication at 3p25.2, partially including RAF1. A similar RAF1 microduplication has been observed in a patient with testicular aplasia. This suggests that some patients with isolated cryptorchidism may harbor Ras/MAPK pathway gene CNVs.

Collagen extraction from mussel byssus: a new marine collagen source with physicochemical properties of industrial interest

Mussel byssus is a by-product of mussel production and is a potential source of collagen. The goal of this study was to extract collagen from the byssus of Chilean mussel using an enzymatic method and characterize it. A pepsin-aided extraction method was employed where first an enzymatic hydrolysis at two pepsin/substrate ratios (1:50 or 4:50) and times (4 or 24 h) was done. Extraction was conducted at 80 °C for 24 h, in a 0.5 N acetic acid solution. All samples were analyzed for collagen content, amino acid profile, turbidity, viscosity, solubility, denaturation temperature and surface tension. Hydrolysis time had significant effect on collagen content, hydroxyproline content and extraction yield. Hydrolysis with a pepsin/byssus ratio of 4:50 for 24 h gave the better extraction performance with values of 69 mg/g protein, 1.8 mg/g protein and 30%, for collagen content, hydroxyproline content and extraction yield, respectively. No differences were found for the viscosity and surface tension of collagen dispersions, suggesting that the enzymatic hydrolysis did not affect the integrity of the collagen molecule. Denaturation temperature of freeze-dried byssus collagen presented a high value (83-91 °C), making this kind of collagen a very interesting material for encapsulation of bioactive molecules and for biomedical applications.

Goldfish hippocampal pallium is essential to associate temporally discontiguous events

There is general agreement that the hippocampus of vertebrates, from fish to mammals, is involved in map-like spatial memory. However, in mammals the role of the hippocampus goes beyond the spatial domain as it is also involved in binding the temporally separate events that compose episodic memories. In this regard, the hippocampus of mammals is essential for trace classical conditioning, in which a stimulus-free time gap separates the conditioned stimulus (CS) and the unconditioned stimulus (US), but not for delay conditioning, in which both stimuli coincide in time. Although the involvement of the hippocampus in encoding relational memories based on a temporal frame-work has been extensively studied in mammals, there is scarce evidence about the possible contribution of the hippocampus of non-mammalian vertebrates to the temporal, non-spatial dimension of relational memories. The present work was aimed to determine if the ventral part of the lateral division of the area dorsalis telencephali (Dlv) of goldfish, proposed as homologous to the hippocampus of mammals, is also involved in trace classical conditioning. With this purpose, goldfish with lesions in Dlv, complete telencephalon ablation and sham operation, were trained in delay and trace heart rate classical conditioning. Dlv lesions severely impaired the acquisition of the conditioned response when a stimulus-free time gap was elapsed between the CS and the US (trace conditioning), but not when both stimuli overlapped in time (delay conditioning), revealing that this region, like the hippocampus of mammals, is essential to form the temporal associative memories required by trace conditioning. Present data suggest that the presence of a hippocampal pallium involved in relational, episodic-like memory that preserves both the spatial and the temporal dimensions of past events, could be a primitive feature of the vertebrate brain that has been conserved through evolution.

Pseudoautosomal abnormalities in terminal AZFb+c deletions are associated with isochromosomes Yp and may lead to abnormal growth and neuropsychiatric function

STUDY QUESTION

Are copy number variations (CNVs) in the pseudoautosomal regions (PARs) frequent in subjects with Y-chromosome microdeletions and can they lead to abnormal stature and/or neuropsychiatric disorders?

SUMMARY ANSWER

Only subjects diagnosed with azoospermia factor (AZF)b+c deletions spanning to the end of the Y chromosome (i.e. terminal deletions) harbor Y isochromosomes and/or cells 45,X that lead to pseudoautosomal gene CNVs, which were associated with abnormal stature and/or neuropsychiatric disorders.

WHAT IS KNOWN ALREADY

The microdeletions in the long arm of the Y chromosome (Yq) that include the loss of one to three AZF regions, referred to as Yq microdeletions, constitute the most important known etiological factor for primary spermatogenic failure. Recently, controversy has arisen about whether Yq microdeletions are associated with gain or loss of PAR genes, which are implicated in skeletal development and neuropsychiatric function.

STUDY DESIGN, SIZE, DURATION

We studied a cohort of 42 Chilean patients with complete AZF deletions (4 AZFa, 4 AZFb, 23 AZFc, 11 AZFb+c) from a university medical center, diagnosed over a period of 15 years. The subjects underwent complete medical examinations with special attention to their stature and neuropsychiatric function.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All subjects were characterized for Yq breakpoints by PCR, and for CNVs in PARs by multiplex ligation-dependent probe amplification (MLPA), followed by qPCR analysis for genes in PAR1 (SHOX and ZBED1), PAR2 (IL9R) and two single copy genes (SRY and DDX3Y, respectively located in Yp11.3 and AZFa). In addition, karyotypes revision and fluorescence in situ hybridization (FISH) for SRY and centromeric probes for X (DXZ1) and Y (DYZ3) chromosomes were performed in males affected with CNVs.

MAIN RESULTS AND THE ROLE OF CHANCE

We did not detect CNVs in any of the 35 AZF-deleted men with interstitial deletions (AZFa, AZFb, AZFc or AZFb+c). However, six of the seven patients with terminal AZFb+c deletions showed CNVs: two patients showed a loss and four patients showed a gain of PAR1 genes, with the expected loss of VAMP-7 in PAR2. In these patients, the Yq breakpoints localized to the palindromes P8, P5 or P4. In the four cases with gain of PAR1, qPCR analysis showed duplicated signals for SRY and DDX3Y and one copy of IL9R, indicating isodicentric Yp chromosomes [idic(Y)] with breakpoint in Yq11.22. The two patients who had loss of PAR1, as shown by MLPA, had an additional reduction for SRY and DDX3Y, as shown by qPCR, associated with a high proportion of 45,X cells, as determined by FISH and karyotype. In agreement with the karyotype analysis, we detected DYZ3++ and DYZ3+ cells by FISH in the six patients, confirming idic(Y) and revealing additional monocentric Y chromosome [i(Y)]. Five patients had a history of major depressive disorders or bipolar disorder, and three had language impairment, whereas two patients showed severe short stature (Z score: -2.75 and -2.62), while a man with bipolar disorder was very tall (Z score: +2.56).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The number of males studied with Y-chromosome microdeletions and normozoospermic controls with normal karyotypes may not be enough to rule out an association between AZF deletions and PAR abnormalities. The prevalence of Y isochromosomes and/or 45,X cells detected in peripheral blood does not necessarily reflect the variations of PAR genes in target tissues.

WIDER IMPLICATIONS OF THE FINDINGS

This study shows that CNVs in PARs were present exclusively in patients with terminal AZFb+c deletions associated with the presence of Y isochromosomes and 45,X cells, and may lead to neuropsychiatric and growth disorders. In contrast, we show that men with interstitial Yq microdeletions with normal karyotypes do not have an increased risk of PAR abnormalities and of phenotypical consequences. Moreover, our results highlight the importance of performing molecular studies, which are not considered in the usual screening for patients with Yq microdeletions.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the National Fund for Scientific and Technological Development of Chile (FONDECYT), grant no. 1120176 (A.C.). The authors declare that no conflicting interests exist.

Relational and procedural memory systems in the goldfish brain revealed by trace and delay eyeblink-like conditioning

The presence of multiple memory systems supported by different neural substrata has been demonstrated in animal and human studies. In mammals, two variants of eyeblink classical conditioning, differing only in the temporal relationships between the conditioned stimulus (CS) and the unconditioned stimulus (US), have been widely used to study the neural substrata of these different memory systems. Delay conditioning, in which both stimuli coincide in time, depends on a non-relational memory system supported by the cerebellum and associated brainstem circuits. In contrast, trace conditioning, in which a stimulus-free time gap separates the CS and the US, requires a declarative or relational memory system, thus depending on forebrain structures in addition to the cerebellum. The distinction between the explicit or relational and the implicit or procedural memory systems that support trace and delay classical conditioning has been extensively studied in mammals, but studies in other vertebrate groups are relatively scarce. In the present experiment we analyzed the differential involvement of the cerebellum and the telencephalon in delay and trace eyeblink-like classical conditioning in goldfish. The results show that whereas the cerebellum lesion prevented the eyeblink-like conditioning in both procedures, the telencephalon ablation impaired exclusively the acquisition of the trace conditioning. These data showing that comparable neural systems support delay and trace eyeblink conditioning in teleost fish and mammals suggest that these separate memory systems and their neural bases could be a shared ancestral brain feature of the vertebrate lineage.

Structural Metastability and Quantum Confinement in Zn1-xCoxO Nanoparticles

This paper investigates the electronic structure of wurtzite (W) and rock-salt (RS) Zn1-xCoxO nanoparticles (NPs) by means of optical measurements under pressure (up to 25 GPa), X-ray absorption, and transmission electron microscopy. W-NPs were chemically synthesized at ambient conditions and RS-NPs were obtained by pressure-induced transformation of W-NPs. In contrast to the abrupt phase transition in W-Zn1-xCoxO as thin film or single crystal, occurring sharply at about 9 GPa, spectroscopic signatures of tetrahedral Co(2+) are observed in NPs from ambient pressure to about 17 GPa. Above this pressure, several changes in the absorption spectrum reveal a gradual and irreversible W-to-RS phase transition: (i) the fundamental band-to-band edge shifts to higher photon energies; (ii) the charge-transfer absorption band virtually disappears (or overlaps the fundamental edge); and (iii) the intensity of the crystal-field absorption peaks of Co(2+) around 2 eV decreases by an order of magnitude and shifts to 2.5 eV. After incomplete phase transition pressure cycles, the absorption edge of nontransformed W-NPs at ambient pressure exhibits a blue shift of 0.22 eV. This extra shift is interpreted in terms of quantum confinement effects. The observed gradual phase transition and metastability are related to the NP size distribution: the larger the NP, the lower the W-to-RS transition pressure.

“Gas and Fat Embolic Syndrome” Involving a Mass Stranding of Beaked Whales (Family Ziphiidae) Exposed to Anthropogenic Sonar Signals

A study of the lesions of beaked whales (BWs) in a recent mass stranding in the Canary Islands following naval exercises provides a possible explanation of the relationship between anthropogenic, acoustic (sonar) activities and the stranding and death of marine mammals. Fourteen BWs were stranded in the Canary Islands close to the site of an international naval exercise (Neo-Tapon 2002) held on 24 September 2002. Strandings began about 4 hours after the onset of midfrequency sonar activity. Eight Cuvier's BWs (Ziphius cavirostris), one Blainville's BW (Mesoplodon densirostris), and one Gervais' BW (Mesoplodon europaeus) were examined postmortem and studied histopathologically. No inflammatory or neoplastic processes were noted, and no pathogens were identified. Macroscopically, whales had severe, diffuse congestion and hemorrhage, especially around the acoustic jaw fat, ears, brain, and kidneys. Gas bubble-associated lesions and fat embolism were observed in the vessels and parenchyma of vital organs. In vivo bubble formation associated with sonar exposure that may have been exacerbated by modified diving behavior caused nitrogen supersaturation above a threshold value normally tolerated by the tissues (as occurs in decompression sickness). Alternatively, the effect that sonar has on tissues that have been supersaturated with nitrogen gas could be such that it lowers the threshold for the expansion of in vivo bubble precursors (gas nuclei). Exclusively or in combination, these mechanisms may enhance and maintain bubble growth or initiate embolism. Severely injured whales died or became stranded and died due to cardiovascular collapse during beaching. The present study demonstrates a new pathologic entity in cetaceans. The syndrome is apparently induced by exposure to mid-frequency sonar signals and particularly affects deep, long-duration, repetitive-diving species like BWs.

Pre-Clinical Evaluation of a Real-Time PCR Assay on a Portable Instrument as a Possible Field Diagnostic Tool: Experiences from the Testing of Clinical Samples for African and Classical Swine Fever Viruses

African swine fever (ASF) and classical swine fever (CSF) are two highly infectious transboundary animal diseases (TADs) that are serious threats to the pig industry worldwide, including in China, the world's largest pork producer. In this study, a duplex real-time PCR assay was developed for the rapid detection and differentiation of African swine fever virus (ASFV) and classical swine fever virus (CSFV). The assay was performed on a portable, battery-powered PCR thermocycler with a low sample throughput (termed as 'T-COR4 assay'). The feasibility and reliability of the T-COR4 assay as a possible field method was investigated by testing clinical samples collected in China. When evaluated with reference materials or samples from experimental infections, the assay performed in a reliable manner, producing results comparable to those obtained from stationary PCR platforms. Of 59 clinical samples, 41 had results identical to a two-step CSFV real-time PCR assay. No ASFV was detected in these samples. The T-COR4 assay was technically easy to perform and produced results within 3 h, including sample preparation. In combination with a simple sample preparation method, the T-COR4 assay provides a new tool for the field diagnosis and differentiation of ASF and CSF, which could be of particular value in remote areas.

Gait Disorder in a Cohort of Patients With Mild and Moderate Alzheimer's Disease

Gait disturbance results in an increase in the risk of falls in patients with Alzheimer's disease (AD). The falls are events that might be related to an increase in the number of fractures, loss of mobility, being bedridden, early institutionalization, and increased use of medication. Therefore, the reduction in the number of falls is important for the maintenance of the functional independence of the patients as well as for the prevention of sequelae resulting from those events. Alterations in the gait occur very frequently in AD, and the gait disturbance occurs relatively early in the course of the disease. This study has important implications for public health and clinical practice. This study and previous studies have reported that abnormal gait predicts greater risk of falls, dementia, institutionalization, and death. The high prevalence and incidence of abnormal gait and its association with multiple adverse outcomes in older adults require urgent attention. Our results allow us to identify the risk factors.

Spatial learning-related changes in metabolic brain activity contribute to the delimitation of the hippocampal pallium in goldfish

Comparative neuroanatomical, developmental and functional evidence suggests that the lateral division of the area dorsalis telencephali (Dl) of the teleost fish is homologous to the hippocampus of tetrapods. Nonetheless, some important aspects of the organization of the hippocampal pallium of teleosts are still under discussion and conflicting hypotheses regarding the extension and demarcation of this region have been proposed. Thus, whereas some authors suggest that the entire Dl region, including its dorsal (Dld) and ventral (Dlv) subdivisions, is homologue to the mammalian hippocampus, others claim that only Dlv should be considered as such. To further elucidate this debate, we investigated the role of Dld and Dlv in one of the most unambiguous functions of the hippocampus, spatial learning. We trained goldfish in a spatial constancy task and mapped the activity of Dld, Dlv, and the medial division of the area dorsalis telencephali (Dm) by means of cytochrome oxidase (CO) histochemistry. The results revealed that training goldfish in the spatial constancy task significantly increased the metabolic activity in Dlv, but not in Dld or Dm, suggesting that only Dlv is critically involved in spatial learning and in this regard comparable to the hippocampus. These data provide additional functional support to the hypotheses that consider Dl as a heterogeneous pallial region and propose that Dlv, but not Dld, might be homologous to the hippocampus.

Adverse reactions to immunotherapy are associated with different patterns of sensitization to grass allergens

The aim of the study was to investigate whether adverse drug reactions (ADRs) during immunotherapy with a grass extract (AVANZ® Phleum, ALK-Abelló) are related to the different patterns of sensitization of patients to grass allergens. A total of 192 patients with rhinitis and/or asthma sensitized to grass pollen received a 4-week updosing with five injections. ADRs were evaluated following EAACI guidelines. A total of 432 ADRs in 133 (69%) patients were recorded, 64% local and 31% systemic. There was a significant association between the number of grass allergens that sensitized the patients and the total number of ADRs (P = 0.004) occurred locally (P = 0.003) and systemically (P = 0.01). Sensitization to Phl p1 + Phl p5 or Phl p1 + Phl p5 + Phl p12 was significantly associated with a higher frequency of local or systemic reactions (P = 0.001, both). Different patterns of sensitization to grass allergens may potentially be considered a risk marker to the development of ADRs to immunotherapy.

Differential cytokine expression in natural and experimental mastitis induced by Mycoplasma agalactiae in dairy goats

Cytokines, primarily produced by macrophages and lymphocytes, mobilize the immune system in response to infection, particularly at mucosal surfaces. Knowledge of the pathogenesis and persistence of Mycoplasma agalactiae (Ma) in the mammary gland is still insufficient. The aim of this study was to elucidate the role of cytokines in the pathogenesis of caprine mastitis caused by Ma. Cytokine expression was evaluated by immunohistochemical methods in the inflammatory lesions of 10 (5 naturally and 5 experimentally infected) goats with Ma-induced mastitis. Immunolabelling for IL-10, IFN-γ, IL-4 and TNF-α was observed in inflammatory cells within the lumen of acini and ducts and in the interstitial spaces and was usually associated with the presence of Ma antigen. The results suggest that cytokines play a role in the pathophysiological processes during Ma infection as differential expression of these cytokines was detected in relation to the course of the infection.

Cyclooxygenase-2 expression in pigs infected experimentally with Mycoplasma hyopneumoniae

Porcine enzootic pneumonia, primarily caused by Mycoplasma hyopneumoniae (Mh), is a contagious disease characterized by catarrhal bronchointerstitial pneumonia. Previous studies have evaluated immunohistochemically the distribution of Mh, different cellular populations and cytokines during Mh-induced pneumonia. Cyclooxygenase (COX)-2 is overexpressed during inflammatory responses by different cell types in the lung. The aim of this study was to elucidate the possible role of COX-2 in the pathogenesis of porcine enzootic pneumonia. COX-2 protein was detected by immunohistochemistry in formalin-fixed, paraffin wax-embedded lung tissues from 10 pigs infected experimentally with Mh. Ten pigs were inoculated intranasally with Mh and killed in pairs weekly from 1 to 5 weeks post inoculation. Three Mh-free pigs were taken as controls. Bronchial and bronchiolar epithelial cells, bronchial submucosal glands and a small number of macrophages in the bronchoalveolar exudate expressed COX-2. COX-2 protein was always associated with areas of pneumonia and expression was minimal in lungs from control pigs. These results suggest that COX-2 plays a role in the pathogenesis of Mh-infection.

Magnetization Measurements on Iron (III)Solutions for Detecting Oligomer Formation

By measuring the magnetization at low temperatures (near 1 K) and intense magnetic fields ( ≳100 KG), information about oligomer formation in ferric salts solutions can be obtained. It is shown that, under rather general conditions, the magnetic moment per ferric ion of a given ferric solution measured in the saturation regime should be equal to 5 β if all the complexes involved in the solution are high-spin monomers. Moreover, if the solution is mainly composed by monomeric species and antiferromagnetic dimers, the relative concentration of monomeric and dimeric species can easily be determined. This techniques has been applied to solutions of Cl3Fe and (NO3)3Fe9H2O in isopropanol as solvent containing about 0.4 M of water. In the first case the present measurements are consistent with the existence of dihydroxo ferric dimers suggested by previous Mössbauer and Optical Absorption data. The relative concentration of these dimers increases from 25% to 50% when the water content increases from 0.4 M to ~ 10 M. In the second case it is confirmed that the solution is mainly composed by oligomers, the relative concentration of monomeric species being less than 30%.

Jumping performance profile of male and female gymnasts

AIM

The aim of this study was to establish a more precise jumping performance profile of elite gymnasts than that published in previous studies.

METHODS

Seventy-six elite male and female competitive gymnasts and 91 moderately active subjects volunteered for the study. The jumping tests performed on a contact mat were: squat jump (SJ) with progressive loads of 0%, 25%, 50 %, 75% and 100% of body mass, counter-movement jump (CMJ), and counter-movement jump with arm swing (CMJA). The parameters used to assess the jumping performance were flight time (FT, ms), FT normalized to body mass (FTbm, ms/kg), estimated elastic component (EC) and arm participation (AP). In SJ, the overload with respect to body mass had a negative impact on reliability in all of the subgroups that were analysed. When overloads were above 50% of body mass in SJ, reliability was poor. Therefore, overloads should not be used with sedentary young females. Gymnasts carry out a large number of jumps from very young ages, which may explain their high jump reliability (ICC>0.91).

RESULTS

We used FT to estimate the F-v curve through SJ with overloads. The curves for male gymnasts and their controls were practically identical. However, when FT was normalized to body mass (FTbm), the F-v curve showed the advantage of female gymnasts in particular over their control group when overloads were above 50%. Larger, more significant (P<0.001) differences between gymnasts and their control groups were observed in CMJ and CMJA, with FTbm instead of FT. The combination of poor SJ and good CMJ performances explains why the EC was higher in gymnasts than in controls (+27%).

CONCLUSION

The better AP of the gymnasts (+79%) may be due to better arm strength conditioning and segmental coordination. EC and AP can be considered a suitable complementary parameter of jumping performance in gymnasts.

Phenotypes and endotypes of uncontrolled severe asthma: new treatments

Severe asthma is a heterogeneous disease that affects only 5%-10% of asthmatic patients, although it accounts for a significant percentage of the consumption of health care resources. Severe asthma is characterized by the need for treatment with high doses of inhaled corticosteroids and includes several clinical and pathophysiological phenotypes. To a large extent, this heterogeneity restricts characterization of the disease and, in most cases, hinders the selection of appropriate treatment. In recent years, therefore, emphasis has been placed on improving our understanding of the various phenotypes of severe asthma and the identification of biomarkers for each of these phenotypes. Likewise, the concept of the endotype has been gaining acceptance with regard to the various subtypes of the disease, which are classified according to their unique functional or pathophysiological mechanism. This review discusses the most relevant aspects of the clinical and inflammatory phenotypes of severe asthma, including severe childhood asthma and the various endotypes of severe asthma. The main therapeutic options available for patients with uncontrolled severe asthma will also be reviewed.

Isolation of an Eimeria ninakohlyakimovae field strain (Canary Islands) and analysis of its infection characteristics in goat kids

The current study was conducted to isolate a field strain of Eimeria ninakohlyakimovae, characterize its infectivity and the response to challenge under experimental conditions. The isolated strain (GC) induced a prepatent period of 14-15 days p.i., a patency of 7±2 days and a noticeable pathogenicity in infected goat kids. Challenge trials resulting in a decrease of oocysts per gram counts as well as a milder intensity of clinical signs in re-infected animals indicated the capacity of this strain to induce protective immune response. Altogether, the data reported in the present study suggest that the strain E. ninakohlyakimovae GC is a useful tool for the investigation of mechanisms of pathogenicity as well as host protective immune response in caprine coccidiosis, representing a valuable prerequisite for the development of future strategies in prophylaxis and control of this important parasitic disease in goat.

Clinical and molecular epidemiology of meticillin-resistant Staphylococcus aureus causing bacteraemia in Southern Spain

BACKGROUND

Some molecular features of meticillin-resistant Staphylococcus aureus (MRSA) isolates causing invasive infections have been shown to have clinical implications. There is a need to monitor the situation using a combination of molecular and clinical data because, although MRSA clones tend to predominate over wide geographical areas, clonal shifts may take place.

AIM

To study the epidemiological features and perform molecular characterization of a retrospective cohort of 98 cases of nosocomial and healthcare-associated MRSA bacteraemia in 10 hospitals in Andalusia, Spain.

METHODS

Relatedness of isolates was investigated using pulsed-field gel electrophoresis (PFGE), S. aureus protein A (spa) typing and clonal complex (CC) assignment. Staphylococcal chromosomal cassette mec (SCCmec) type and accessory gene regulator (agr) group were studied by polymerase chain reaction. agr function was assessed.

RESULTS

Most isolates were CC5, SCCmec type IV and agr group II. The most common spa type was t067. Six major clusters were identified by PFGE. Six small clusters of epidemiologically related cases sharing isolates from the same PFGE subtype were identified. Five percent of isolates had a vancomycin minimum inhibitory concentration (MIC) of 2 μg/mL on broth microdilution, although 44% had an MIC >1 μg/mL on E-test. Variables independently associated with MIC >1 mg/L on E-test were surgery during present admission and Charlson index ≥2.

CONCLUSION

A specific CC that has been predominant in Spain over the last decade caused most of the cases in this study. PFGE was more discriminatory than spa typing in showing clusters of epidemiologically related cases. Some patient features were associated with vancomycin MIC >1 mg/L on E-test.