Comparative study of the whisky aroma profile based on headspace solid phase microextraction using different fibre coatings

A dynamic headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled to ion trap mass spectrometry (GC-(IT)MS) method was developed and applied for the qualitative determination of the volatile compounds present in commercial whisky samples which alcoholic content was previously adjusted to 13% (v/v). Headspace SPME experimental conditions, such as fibre coating, extraction temperature and extraction time, were optimized in order to improve the extraction process. Five different SPME fibres were used in this study, namely, poly(dimethylsiloxane) (PDMS), poly(acrylate) (PA), Carboxen-poly(dimethylsiloxane) (CAR/PDMS), Carbowax-divinylbenzene (CW/DVB) and Carboxen-poly(dimethylsiloxane)-divinylbenzene (CAR/PDMS/DVB). The best results were obtained using a 75 microm CAR/PDMS fibre during headspace extraction at 40 degrees C with stirring at 750 rpm for 60 min, after saturating the samples with salt. The optimised methodology was then applied to investigate the volatile composition profile of three Scotch whisky samples--Black Label, Ballantines and Highland Clan. Approximately seventy volatile compounds were identified in the these samples, pertaining at several chemical groups, mainly fatty acids ethyl esters, higher alcohols, fatty acids, carbonyl compounds, monoterpenols, C13 norisoprenoids and some volatile phenols. The ethyl esters form an essential group of aroma components in whisky, to which they confer a pleasant aroma, with "fruity" odours. Qualitatively, the isoamyl acetate, with "banana" aroma, was the most interesting. Quantitatively, significant components are ethyl esters of caprilic, capric and lauric acids. The highest concentration of fatty acids, were observed for caprilic and capric acids. From the higher alcohols the fusel oils (3-methylbutan-1-ol and 2.phenyletanol) are the most important ones.

Influence of non-steroidal anti-inflammatory drugs on renal function and 24h ambulatory blood pressure-reducing effects of enalapril and nifedipine gastrointestinal therapeutic system in hypertensive patients

OBJECTIVE

To evaluate the influence of non-steroidal anti-inflammatory drugs (NSAIDs; aspirin and indomethacin) on the renal and antihypertensive effects of enalapril and nifedipine gastrointestinal therapeutic system (GITS) in patients with essential hypertension.

DESIGN AND METHODS

In a crossover study, 18 patients on an unrestricted-salt diet were randomly assigned to receive either enalapril (20-40 mg/day) or nifedipine-GITS (30-60 mg/day) for 4-8 weeks, followed by aspirin (100 mg/day for 2 weeks) and then indomethacin (75 mg/day for 1 week). Blood pressure was measured by 24h ambulatory monitoring.

RESULTS

Enalapril and nifedipine-GITS significantly reduced blood pressure compared with placebo. Aspirin did not alter the antihypertensive effect of either drug. Indomethacin attenuated (by 45%) the antihypertensive effect of enalapril throughout the 24h period of evaluation, but did not interfere with the effect of nifedipine. Furthermore, indomethacin significantly reduced the fractional excretion of sodium and plasma levels of prostaglandins in a similar way when added to either the enalapril or the nifedipine regimen.

CONCLUSIONS

Vasodilatory prostaglandins are probably involved in the antihypertensive effects of enalapril but not of nifedipine, and this interaction seems to be independent of any indomethacin-induced decrease in renal sodium excretion. Nifedipine may be an appropriate drug to treat hypertensive patients requiring concomitant therapy with NSAID.

Genetic manipulation of Patescibacteria provides mechanistic insights into microbial dark matter and the epibiotic lifestyle

Patescibacteria, also known as the candidate phyla radiation (CPR), are a diverse group of bacteria that constitute a disproportionately large fraction of microbial dark matter. Its few cultivated members, belonging mostly to Saccharibacteria, grow as epibionts on host Actinobacteria. Due to a lack of suitable tools, the genetic basis of this lifestyle and other unique features of Patescibacteira remain unexplored. Here, we show that Saccharibacteria exhibit natural competence, and we exploit this property for their genetic manipulation. Imaging of fluorescent protein-labeled Saccharibacteria provides high spatiotemporal resolution of phenomena accompanying epibiotic growth, and a transposon-insertion sequencing (Tn-seq) genome-wide screen reveals the contribution of enigmatic Saccharibacterial genes to growth on their hosts. Finally, we leverage metagenomic data to provide cutting-edge protein structure-based bioinformatic resources that support the strain Southlakia epibionticum and its corresponding host, Actinomyces israelii, as a model system for unlocking the molecular underpinnings of the epibiotic lifestyle.

Nasal polyps: a manifestation of allergy?

The cause of nasal polyps is speculative. In the 1930s nasal polyps were considered to be a manifestation of allergy. This theory was challenged in the 1970s. Many patients with nasal polyps have no identifiable allergic disease. The purpose of this study is to better define the relationship between allergy and nasal polyps. Twelve patients with nasal polyps were evaluated by history, physical examination, skin testing, nasal smear for eosinophils, specific IgE determination from serum, nasal secretions, and nasal polyp fluid. Similar data were collected from three control groups: (1) 10 patients with allergic rhinitis, (2) 10 patients with nonallergic rhinitis, and (3) 10 patients with no known nasal disease. By comparing the incidence of markers for allergic disease in patients with nasal polyposis to each of the three control groups, the role of allergic disease in nasal polyposis was delineated.

Genome-wide protein-DNA interaction site mapping in bacteria using a double-stranded DNA-specific cytosine deaminase

DNA-protein interactions are central to fundamental cellular processes, yet widely implemented technologies for measuring these interactions on a genome scale in bacteria are laborious and capture only a snapshot of binding events. We devised a facile method for mapping DNA-protein interaction sites in vivo using the double-stranded DNA-specific cytosine deaminase toxin DddA. In 3D-seq (DddA-sequencing), strains containing DddA fused to a DNA-binding protein of interest accumulate characteristic mutations in DNA sequence adjacent to sites occupied by the DNA-bound fusion protein. High-depth sequencing enables detection of sites of increased mutation frequency in these strains, yielding genome-wide maps of DNA-protein interaction sites. We validated 3D-seq for four transcription regulators in two bacterial species, Pseudomonas aeruginosa and Escherichia coli. We show that 3D-seq offers ease of implementation, the ability to record binding event signatures over time and the capacity for single-cell resolution.

On a new species of Hysterothylacium (Nematoda: Anisakidae) from Cauque mauleanum (Pisces: Atherinidae) by brightfield and scanning electron microscopy

Hysterothylacium geschei n. sp. (Nematoda, Anisakidae) is described from the intestine of Cauque mauleanum (Steindachner) (Pisces: Atherinidae) from Lake Panguipulli (39 degrees-43'S; 72 degrees-13'W), Chile. Eleven (78.6%) out of 14 fish were infected, with a mean intensity (range) of 14.4 (1-55) worms. The new species can be differentiated from the two previously described species of freshwater fishes from South America by the presence of lateral alae, the number of caudal papillae, and the length of the spicules, oesophagus, intestinal caecum, distance vulva-anterior extremity and the length ratio intestinal caecum: ventricular appendix. From the fishes examined in Lake Panguipulli, including the introduced salmonid species Oncorhynchus mykiss (Walbaum) and the authochthonous species Basilichthys australis Eigenmann (Atherinidae) and Percichthys trucha (Valenciennes) (Percichthyidae), only one specimen of P. trucha was found parasitized by a third-stage larva of this species.

Mesenteric arteriovenous fistula causing portal hypertension and bleeding duodenal varices

We report a case of portal hypertension associated with a non-traumatic arteriovenous fistula, presenting with bleeding duodenal varices. The patient was admitted for melaena. Emergency endoscopy showed oesophageal varices with no signs of recent bleeding and with no blood in the upper gastrointestinal tract. Arteriography of the coeliac axis and superior mesenteric artery failed to detect any bleeding source. Endoscopy was repeated because of persistent bleeding and revealed active bleeding from varices in the distal duodenum. The patient underwent surgery and a large paraduodenal varicose vein associated with an arteriovenous fistula was found. Resection of the paramural varix and surgical occlusion of the arteriovenous fistula were effective in the control of bleeding. Liver biopsy revealed mild portal fibrosis without cirrhosis. Three years after surgery the patient still has oesophageal varices but has not had recurrent bleeding. There was regression of intraduodenal varices.

Linear psoriasis - a case report

A 56-year-old woman presented with a 3-month history of erythematous plaques covered by scales and limited to the right side of her body. The plaques were arranged along Blaschko's lines with a marked mid-line cutoff. The histopathologic analysis of a skin biopsy in conjunction with the anamnesis allowed the diagnosis of linear psoriasis. Our patient showed a good clinical response to antipsoriatic treatment.

Endosonography in the diagnosis of "blue rubber bleb nevus syndrome": an uncommon cause of gastrointestinal tract bleeding

Blue rubber bleb nevus syndrome is a rare condition characterized by the presence of multiple angiomatic lesions of the skin. These are associated with similar lesions in other organs, namely in the gastrointestinal tract, causing anemia through chronic bleeding. We describe the case of a 72-year-old woman with microcytic anemia. A barium study revealed irregular lacunae in the distal esophagus. A subsequent endoscopy showed blue nodular lesions similar to angiomas of the esophagus and stomach fundus. Endosonography confirmed its angiomatic nature. Exploration of other organs, using magnetic resonance and cranial computed tomography, did not reveal the presence of this type of lesion. In physical examination, two angiomatic lesions were observed on the face and lips, respectively. These were blue in color and compressible, leaving an empty wrinkled sac that rapidly refilled, typical of angiomas.

Lack of congruence between morphometric evolution and genetic differentiation suggests a recent dispersal and local habitat adaptation of the Madeiran lizard Lacerta dugesii

Genetic differentiation among nine populations of the endemic lizard Lacerta dugesii Milne-Edwards 1829 (Lacertidae) from four groups of islands constituting the Archipelago of Madeira, was investigated by protein electrophoresis at 23 enzyme loci. Among twenty polymorphic loci, the total genetic diversity was due primarily to intra-population variation. The allele and genotypic frequencies among populations showed some heterogeneity, allowing the species to present a structuring pattern compatible with their geographical clustering. Some evidence suggests that selection acting on some loci in different ecological conditions may be responsible for the clustering of the populations studied. There was no apparent isolation effect expected under an "island" model of population divergence, and no correlation was found between genetic and geographic distances among populations. Morphological variation of the proposed three L. dugesii subspecies is not congruent with the allozyme analysis. This most probably suggests a rapid colonization of the islands followed by a strong effect of selection operating over the morphological characters used to define the subspecies.

Artificial intelligence and colon capsule endoscopy: development of an automated diagnostic system of protruding lesions in colon capsule endoscopy

BACKGROUND

Colon capsule endoscopy (CCE) is a minimally invasive alternative for patients unwilling to undergo conventional colonoscopy, or for whom the latter exam is contraindicated. This is particularly important in the setting of colorectal cancer screening. Nevertheless, these exams produce large numbers of images, and reading them is a monotonous and time-consuming task, with the risk of overlooking important lesions. The development of automated tools based on artificial intelligence (AI) technology may improve some of the drawbacks of this diagnostic instrument.

METHODS

A database of CCE images was used for development of a Convolutional Neural Network (CNN) model. This database included anonymized images of patients with protruding lesions in the colon or patients with normal colonic mucosa or with other pathologic findings. A total of 3,387,259 frames from 24 CCE exams were retrospectively reviewed. For CNN development, 3640 images (860 protruding lesions and 2780 with normal mucosa or other findings) were ultimately extracted. Training and validation datasets were constructed for the development and testing of the CNN.

RESULTS

The CNN detected protruding lesions with a sensitivity, specificity, positive and negative predictive values of 90.7, 92.6, 79.2 and 96.9%, respectively. The area under the receiver operating characteristic curve for detection of protruding lesions was 0.97.

CONCLUSIONS

The deep learning algorithm we developed is capable of accurately detecting protruding lesions. The application of AI technology to CCE may increase its diagnostic accuracy and acceptance for screening of colorectal neoplasia.

Design and manufacturing of anthropomorphic thyroid-neck phantom for use in nuclear medicine centres in Chile

Anthropomorphic phantoms are used in nuclear medicine for imaging quality control, calibration of gamma spectrometry system for the study of internal contamination with radionuclides and for internal dosimetric studies. These are constructed of materials that have radiation attenuation coefficients similar to those of the different organs and tissues of the human body. The material usually used for the manufacture of phantoms is polymethyl methacrylate. Other materials used for this purpose are polyethylene, polystyrene and epoxy resin. This project presents the design and manufacture of an anthropomorphic thyroid-neck phantom that includes the cervical spine, trachea and oesophagus, using a polyester resin (ρ = 1.1 g cm(-3)). Its linear and mass attenuation coefficients were experimentally determined and simulated by means of XCOM software, finding that this material reproduces the soft tissue ICRU-44 in a range of energies between 80 keV and 11 MeV, with less than a 5 % difference.

A new interpretation of the origin of extradural space negative pressure

The negative pressure in the extradural space is the result of the interaction of hydrostatic forces created between the vertebral canal (a stiff-walled cylinder) and the dura mater, with its content of cerebro-spinal fluid (CSF), which behaves as a cylinder that can collapse according to the position of the subject. In order to corroborate this hypothesis, we have designed a model formed by a sealed, water-filled, glass cylinder ("vertebral canal"). In the interior there is a collapsible, non-distendible, water-filled cylinder ("dural sac"), in free communication with a reservoir which represents the CSF contained in the cranial cavity. Changes in the position of the model produce subatmospheric pressure in the space between both cylinders ("extradural space"), as happens in man.

[Gamma-glutamyltransferase and alcoholic hepatic disease]

Accepting the principle that Gama-gt values are elevated in alcoholic patients, the authors attempted to find out if that enzyme might be helpful in distinguishing alcoholics with or without hepatic morphologic lesion. 110 alcoholic patients with and 57 without histologically proved hepatic lesion were studied. The authors conclude that a single determination of Gama-gt lacks specificity to detect, among the alcoholic individuals, those who already carry a morphologic, nonreversible lesion.

Outcome and risk factors assessment for adverse events in advanced esophageal cancer patients after self-expanding metal stents placement

Self-expanding metal stents (SEMS) are the treatment of choice for advanced esophageal cancers. Literature is scarce on risk factors predictors for adverse events after SEMS placement. Assess risk factors for adverse events after SEMS placement in advanced esophageal cancer and evaluate survival after SEMS placement. Cross-sectional study of patients with advanced esophageal cancer referred for SEMS placement, during a period of 3 years. Ninety-seven patients with advanced esophageal cancer placed SEMS. Adverse events were more common when tumors were located at the level of the distal esophagus/cardia (47% vs 23%, P = 0.011, OR 3.1), with statistical significance being kept in the multivariate analysis (OR 3.1, P = 0.018). Time until adverse events was lower in the tumors located at the level of the distal esophagus/cardia (P = 0.036). Survival was higher in patients who placed SEMS with curative intent (327 days [126-528] vs. 119 days [91-147], P = 0.002) and in patients submitted subsequently to surgery compared with those who did just chemo/radiotherapy or who did not do further treatment (563 days [378-748] vs. 154 days [133-175] vs. 46 days [20-72], P < 0.001). Subsequent treatment kept statistical significance in the multivariate analysis (HR 3.4, P < 0.001). SEMS allow palliation of dysphagia in advanced esophageal cancer and are associated with an increased out-of-hospital survival, as long as there are conditions for further treatments. Tumors located at the level of the distal esophagus/cardia are associated with a greater number of adverse events, which also occur earlier.

Self-care. Substitute, supplement, or stimulus for formal medical care services?

This article examines the relationship between selected self-care practices during an episode of illness and the use of formal medical care. Stimulated by conflicting evidence and assertions, the general question addressed is: "Is self-care a substitute, a supplement, or a stimulus for use of formal medical care services?" Multiple Classification Analysis was used in a secondary data analysis of a 1976 nationwide study on access to medical care. The results suggest that self-care users may visit the physician less often and stay fewer days in the hospital, and thus they are expected to have lower expenditures for hospital and physician services. Therefore, the self-care activities examined appear to be substitutes for, rather than supplements or stimuli to, health services utilization. The results must be viewed with some caution due to limitations in the data. However, the results also argue for a greater research emphasis on self-care.

Extraction efficiencies for pesticides in crops: 14C-benomyl extraction from mustard green and radishes

14C-labeled benomyl [methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate] suspended in a commercial benomyl formulation was sprayed on mustard greens and radishes. At 3 intervals after application, the crops were extracted with methanol, acetonitrile, or acetone. Crops were either blended and leached or repetitively blended followed by Soxhlet extraction. Essentially all of the extractable radioactivity was removed by blending. The 14C was more difficult to extract from radishes than from mustard greens as time increased. Respective percentages of 14C extracted at 1, 7, and 14 days were 99, 98, and 97 from mustard greens and 96, 88, and 79 from radishes. Methanol exhibited the highest extraction efficiency, and the blend-Soxhlet process was better than the blend-leach process. Thin layer chromatography of the organic-soluble extracts indicated that the majority of 14C was recovered as methyl 2-benzimidazole carbamate (MBC), a breakdown product of benomyl. Acid hydrolysis of the extracted tissues released 30--50% of the residual 14C.

Endoscopic injection therapy vs. multipolar electrocoagulation vs. laser vs. injection + octreotide vs. injection + omeprazole in the treatment of bleeding peptic ulcers. A prospective randomized study

BACKGROUND/AIMS

A prospective randomized study was performed to assess the effectiveness and safety of 5 different methods of hemostasis in selected patients with high-risk bleeding peptic ulcers.

METHODOLOGY

Two hundred and eight patients (n = 208; mean age: 61.6 yrs) with endoscopic stigmata of active hemorrhage, non-bleeding vessel or adherent fresh clot were randomized during emergency endoscopy to receive one of the following modalities of endoscopic therapy (with or without pharmacological therapy): I) injection of absolute alcohol (n = 44); II) multipolar electrocoagulation (BICAP; n = 42); III) Nd-YAG laser (n = 40); IV) injection of absolute ethanol + octreotide (n = 42); V) injection of absolute ethanol + omeprazole (n = 40).

RESULTS

The 5 treatment groups were clinically and endoscopically comparable. The initial hemostatic success was > 90% in every group. No significant differences between groups were found in any of the following parameters assessed during hospitalization: incidence of rebleeding (I = 14.8% vs. II = 19.0% vs. III = 16.6% vs. IV = 18.1% vs. V = 20.0%; P > 0.05 mean = 17.7%); incidence of definitive hemostasis (I = 89.3% vs. II = 85.7% vs. III = 86.6% vs. IV = 84.0% vs. V = 86.6%; P > 0.05; mean = 86.5%); incidence of emergency surgery (I = 8.5% vs. II = 11.9% vs. III = 10.0% vs. IV = 6.8% vs. V = 11.1%; P > 0.05; mean = 9.6%); mortality rate (I = 4.2% vs. II = 4.7% vs. III = 3.3% vs. IV = 13.6% vs. V = 4.4%; P > 0.05; mean = 6.2%). Mean age of deceased patients was significantly higher than living patients (71.2 +/- 13.4 vs. 60.9 +/- 14.4; P < 0.05). Approximately 2/3 of the fatal cases were strongly weakened by coexistent medical diseases. The duration of hospital stay was similar for all groups. The BICAP group required less units of blood transfusion (1.9 +/- 1.8 vs. I = 3.0 +/- 2.6; III = 3.5 +/- 3.6; IV = 2.8 +/- 2.3; V = 3.1 +/- 2.5; P < 0.05), perhaps due to the higher mean value of hemoglobin of these patients at hospital admission, compared to all other groups. No significant complications were reported.

CONCLUSIONS

This study provides good evidence that injection of absolute ethanol, multipolar electrocoagulation (BICAP) and Nd-YAG laser are equally safe and effective in the endoscopic therapy of acute bleeding peptic ulcers. In contrast, no additional hemostatic benefits arose from the association of pharmacological agents (octreotide or omeprazole) to sclerosis injection.