Resistance of Antarctic moss Sanionia uncinata to photoinhibition: chlorophyll fluorescence analysis of samples from the western and eastern coasts of the Antarctic Peninsula.

Interspecific differences in sensitivity of the Antarctic moss Sanionia uncinata from King George Island (KGI) and James Ross Island (JRI) to photoinhibitory treatment were studied in laboratory conditions using chlorophyll fluorescence techniques. Slow (Kautsky) and fast (OJIP) kinetics were used for the measurements. Samples were exposed to a short-term (60 min) photoinhibitory treatment (PIT, 2000 µmol·m-2 ·s-1 PAR). The photoinhibitory treatment (PIT) led to photoinhibition which was indicated by the decrease in FV /FM and ΦPSII in KGI but not in JRI samples. However, this decrease was small and full recovery was reached 90 min after PIT termination. Non-photochemical quenching (NPQ) was activated during the PIT, and rapidly relaxed during recovery. Early stages of photoinhibition showed a drop in FV /FM and ΦPSII to minimum values within the first 10 s of the PIT, with their subsequent increase apparent within fast (0-5 min PIT) and slow (5-50 min PIT) phases of adjustment. The PIT caused a decrease in the performance index (Pi_Abs), photosynthetic electron transport per reaction centre (RC) (ET0 /RC). The PIT induced an increase in thermal dissipation per RC (DI0 /RC), effectivity of thermal dissipation (Phi_D0 ), absorption per RC (ABS/RC) and trapping rate per RC (TR0 /RC). In conclusion, PIT led to only slight photoinhibition followed by fast recovery in S. uncinata from KGI and JRI, since FV /FM and ΦPSII returned to pre-photoinhibitory conditions. Therefore, S. uncinata might be considered resistant to photoinhibition even in the wet state. The KGI samples showed higher resistance to photoinhibition than the JRI samples.

Laparoscopic cholecystectomy in patient with situs viscerum inversus totalis and gallbladder empyema - a case report.

The case report presents the successful performance of laparoscopic cholecystectomy for situs viscerum inversus totalis in a female patient with chronic cholecystitis and cholecystolithiasis and summarizes current knowledge and approaches to this issue. Gallbladder empyema was found perioperatively, which has only been published once in a similar case before. Laparoscopic cholecystectomy in situs viscerum inversus totalis is a safe method to remove the gallbladder. Key words: situs viscerum inversus totalis laparoscopic cholecystectomy gallblader empyema.

Effect of UV-B radiation on the content of UV-B absorbing compounds and photosynthetic parameters in Parmotrema austrosinense from two contrasting habitats.

We studied the resistance of Parmotrema austrosinense to UV-B stress. We focused on the effects of a high dose UV-B radiation on the content of chlorophylls, carotenoids and UV-B screening compounds. Photosynthetic parameters were measured by chlorophyll fluorescence (potential and effective quantum yields, photochemical and non-photochemical quenching) and evaluated in control and UV-B-treated lichens. Lichens from two different locations in Cordoba, Argentina, were selected: (i) high altitude and dry plots at (Los Gigantes) and (ii) lowland high salinity plots (Salinas Grandes). UV-B treatment led to a decrease in the content of photosynthetic pigments and UV-B screens (absorbance decrease in 220-350 nm) in the samples from Salinas Grandes, while in Los Gigantes samples, an increase in UV-B screen content was observed. Chlorophyll fluorescence parameters showed a UV-B-induced decline in FV /FM , ΦPSII and qP indicating limitation of primary photosynthetic processes in photosystem II (PSII) of symbiotic alga, more pronounced in Salinas Grandes samples. Protective mechanism of PSII were activated by the UV-B treatment to a higher extent in samples from Salinas Grandes (NPQ 0.48) than in Los Gigantes samples (NPQ 0.26). We concluded that site-related characteristics, and in particular different UV-B radiation regimen, had a strong effect on resistance of the photosynthetic apparatus of P. austrosinense to UV-B radiation.

Impact of pyrazinamide resistance on multidrug-resistant tuberculosis in Karakalpakstan, Uzbekistan.

SETTING: The World Health Organization (WHO) recommends the inclusion of pyrazinamide (PZA) in treatment regimens for multidrug-resistant tuberculosis (MDR-TB) unless resistance has been confirmed. OBJECTIVE: To investigate the association between PZA susceptibility and MDR-TB treatment outcome among patients treated with a PZA-containing regimen and whether the duration of the intensive phase of the PZA-containing regimen affected treatment outcome. DESIGN: We conducted a retrospective cohort study including all eligible MDR-TB patients starting treatment in 2003-2013 in the TB programme in Karakalpakstan, Uzbekistan. PZA drug susceptibility testing (DST) using liquid culture was performed, and outcomes were classified according to the WHO 2013 definitions. RESULTS: Of 2446 MDR-TB patients included, 832 (34.0%) had an available baseline PZA DST result, 612 (73.6%) of whom were PZA-resistant. We found no association between treatment success and PZA susceptibility (adjusted odds ratio [aOR] 0.86, 95%CI 0.51-1.44, P = 0.6) in patients treated with PZA. Furthermore, among patients with no baseline PZA DST result, no evidence was seen of an association between treatment success and PZA treatment duration (aOR 0.86, 95%CI 0.49-1.51, P = 0.6). CONCLUSION: Treatment of MDR-TB with a standard PZA regimen does not appear to improve treatment outcomes, regardless of PZA susceptibility or duration of treatment.

Metal-organic and covalent organic frameworks as single-site catalysts.

Heterogeneous single-site catalysts consist of isolated, well-defined, active sites that are spatially separated in a given solid and, ideally, structurally identical. In this review, the potential of metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) as platforms for the development of heterogeneous single-site catalysts is reviewed thoroughly. In the first part of this article, synthetic strategies and progress in the implementation of such sites in these two classes of materials are discussed. Because these solids are excellent playgrounds to allow a better understanding of catalytic functions, we highlight the most important recent advances in the modelling and spectroscopic characterization of single-site catalysts based on these materials. Finally, we discuss the potential of MOFs as materials in which several single-site catalytic functions can be combined within one framework along with their potential as powerful enzyme-mimicking materials. The review is wrapped up with our personal vision on future research directions.

Towards metal-organic framework based field effect chemical sensors: UiO-66-NH2 for nerve agent detection.

We present a highly sensitive gas detection approach for the infamous 'nerve agent' group of alkyl phosphonate compounds. Signal transduction is achieved by monitoring the work function shift of metal-organic framework UiO-66-NH2 coated electrodes upon exposure to ppb-level concentrations of a target simulant. Using the Kelvin probe technique, we demonstrate the potential of electrically insulating MOFs for integration in field effect devices such as ChemFETs: a three orders of magnitude improvement over previous work function-based detection of nerve agent simulants. Moreover, the signal is fully reversible both in dry and humid conditions, down to low ppb concentrations. Comprehensive investigation of the interactions that lead towards this high sensitivity points towards a series of confined interactions between the analyte and the pore interior of UiO-66-NH2.

Illness in Canadian travellers and migrants from Brazil: CanTravNet surveillance data, 2013-2016.

BACKGROUND: In light of the 2016 summer Olympic games it is anticipated that Canadian practitioners will require information about common illnesses that may affect travellers returning from Brazil. OBJECTIVE: To identify the demographic and travel correlates of illness among recent Canadian travellers and migrants from Brazil attending a network of travel health clinics across Canada. METHODS: Data was analyzed on returned Canadian travellers and migrants presenting to a CanTravNet site for care of an illness between June 2013 and June 2016. RESULTS: During the study period, 7,707 ill travellers and migrants presented to a CanTravNet site and 89 (0.01%) acquired their illness in Brazil. Tourists were most well represented (n=45, 50.6%), followed by those travelling to "visit friends and relatives" (n=14, 15.7%). The median age was 37 years (range <1-78 years), 49 travellers were men (55.1%) and 40 were women (44.9%). Of the 40 women, 26 (65%) were of childbearing age. Nine percent (n=8) of travellers were diagnosed with arboviruses including dengue (n=6), chikungunya (n=1) and Zika virus (n=1), while another 14.6% (n=13) presented for care of non-specific viral syndrome (n=7), non-specific febrile illness (n=1), peripheral neuropathy (n=1) and non-specific rash (n=4), which are four syndromes that may be indicative of Zika virus infection. Ill returned travellers to Brazil were more likely to present for care of arboviral or Zika-like illness than other ill returned travellers to South America (23.6 per 100 travellers versus 10.5 per 100 travellers, respectively [p=0.0024]). INTERPRETATION: An epidemiologic approach to illness among returned Canadian travellers to Brazil can inform Canadian practitioners encountering both prospective and returned travellers to the Olympic games. Analysis showed that vector-borne illnesses such as dengue are common and even in this small group of travellers, both chikungunya and Zika virus were represented. It is extremely important to educate travellers about mosquito-avoidance measures in advance of travel to Brazil.

Travel-acquired infections in Canada: CanTravNet 2011-2012.

BACKGROUND: Important gaps remain in our knowledge of the infectious diseases people acquire while travelling and the impact of pathogens imported by Canadian travellers. OBJECTIVE: To provide a surveillance update of illness in a cohort of returned Canadian travellers and new immigrants. METHODS: Data on returning Canadian travellers and new immigrants presenting to a CanTravNet site between September 2011 and September 2012 were extracted and analyzed by destination, presenting symptoms, common and emerging infectious diseases and disease severity. RESULTS: During the study period, 2283 travellers and immigrants presented to a CanTravNet site, 88% (N=2004) of whom were assigned a travel-related diagnosis. Top three destinations for non-immigrant travellers were India (N=132), Mexico (N=103) and Cuba (N=89). Fifty-one cases of malaria were imported by ill returned travellers during the study period, 60% (N=30) of which were Plasmodium falciparum infections. Individuals travelling to visit friends and relatives accounted for 83% of enteric fever cases (15/18) and 41% of malaria cases (21/51). The requirement for inpatient management was over-represented among those with malaria compared to those without malaria (25% versus 2.8%; p<0.0001) and those travelling to visit friends and relatives versus those travelling for other reasons (12.1% versus 2.4%; p<0.0001). Nine new cases of HIV were diagnosed among the cohort, as well as one case of acute hepatitis B. Emerging infections among travellers included hepatitis E virus (N=6), chikungunya fever (N=4) and cutaneous leishmaniasis (N=16). Common chief complaints included gastrointestinal (N=804), dermatologic (N=440) and fever (N=287). Common specific causes of chief complaint of fever in the cohort were malaria (N=47/51 total cases), dengue fever (14/18 total cases), enteric fever (14/17 total cases) and influenza and influenza-like illness (15/21 total cases). Animal bites were the tenth most common diagnosis among tourist travellers. INTERPRETATION: Our analysis of surveillance data on ill returned Canadian travellers provides a recent update to the spectrum of imported illness among travelling Canadians. Preventable travel-acquired illnesses and injuries in the cohort include malaria, enteric fever, HIV, hepatitis B, hepatitis A, influenza and animal bites. Strategies to improve uptake of preventive interventions such as malaria chemoprophylaxis, immunizations and arthropod/animal avoidance may be warranted.

Interspecific differences in cryoresistance of lichen symbiotic algae of genus Trebouxia assessed by cell viability and chlorophyll fluorescence.

Unicellular algae of genus Trebouxia are the most frequent symbiotic photobionts found in lichen species adapted to extreme environments. When lichenised, they cope well with freezing temperature of polar regions, high-mountains environments and were successfully tested in open-space experiments. Trebouxia sp. is considered potential model species for exobiological experiments. The aim of this paper is to evaluate cryoresistence of Trebouxia sp. when isolated from lichen thalli and cultivated on media. In our study, six algal strains were exposed to repeated freezing/thawing cycles. The strains of Trebouxia sp. (freshly isolated from lichen Lasallia pustulata), Trebouxia erici, Trebouxia asymmetrica, Trebouxia glomerata, Trebouxia irregularis, and Trebouxia jamesii from culture collection were cooled from 25 to -40 °C at two different rates. The strains were also shock frozen in liquid nitrogen. After repeated treatment, the strains were inoculated and cultivated on a BBM agar for 7 days. Then, cell viability was assessed as relative share of living cells. Potential quantum yield of photochemical reactions in PS II (F(V)/F(M)), and effective quantum yield of photochemical reactions in PS II (Φ(PSII)) were measured. While the slow cooling rate (0.5 °C min(-1)) did not cause any change in viability, F(V)/F(M), and Φ(PSII), the fast cooling rate (6.0 °C min(-1)) caused species-specific decrease in all parameters. The most pronounced interspecific differences in cryoresistance were found after shock freezing and consequent cultivation. While T. asymmetrica and T. jamesii exhibited low viability of living cells (18.9% and 34.7%) and full suppression of photosynthetic processes, the other strains had viability over 60%, and unaffected values of F(V)/F(M), and Φ(PSII). This indicated a high degree of cryoresistance of T. glomerata, T. erici, T. irregularis and Trebouxia sp. strains. These strains could be used for detailed investigation of underlying physiological mechanisms and as models for astrobiological tests taken in the Earth facilities.

[Central venous cannulation under ultrasonographic and fluoroscopic navigation - 2 year experience]. / Centrální kanylace s vyuzitím sonografie a skiaskopie - 2leté zkusenosti.

INTRODUCTION: The aim of our study was to evaluate the influence of ultrasonographic and fluoroscopic navigation on the rate of procedural and early complications during central venous cannulation. MATERIAL AND METHODS: We retrospectively evaluated procedural and early complications in patients who had undergone central venous cannulation under sonographic and fluoroscopic control within a two year period (from January 2010 to December 2011). We studied procedural and early complications (within 24 hours after the procedure). We summarized all cases of pneumothorax, haemothorax and haematoma of soft tissue larger than 5 cm in long axis, and other severe complications e.g. ardiac arrhythmias or hypotension. The set of patients indicated for central venous cannulation included mainly oncological patients who were implanted central venous port systems, and a small group of patients who were cannulated either at the intensive care unit (ICU) or at the department of anesthesiology after unsuccessful blind cannulation. There were three patients cannulated because of transjugular liver biopsy. RESULTS: We cannulated 165 patients under sonographic control within two years. There were 66 men, the mean age of 58.6 years (20-82) and 99 women, the mean age of 58.3 years (36- 94). We cannulated internal jugular vein 148 times and subclavian vein 17 times. The primary technical success was 100% in our study group. Totally, we had 6 complications (3.6%). Immediatelly after the procedure we observed two pneumothoraxes (1.2%) which did not require chest drainage. We punctured artery wall three times, but without haematoma developement, and after a ten-minute commpression, all procedures were successfully finished. We had serious vagal reaction during the cannulation in one patient. We had no fatal procedural complication in our group. There are significantly fewer complications using jugular approach compared to subclavian one. CONCLUSION: We conclude that the ultrasonographic central venous cannulation is a very safe method with a low risk of procedural and early complications. There were significantly fewer complications in case of jugular cannulation compared to subclavian approach in our group of patients. Ultrasonographically navigated central venous cannulation should be used more fequently in emergency medicine as well as in case of non-acute central venous cannulation performed a tan intensive care unit or by anesthesiologists.

Is the delay in diagnosis of pulmonary tuberculosis related to exposure to fluoroquinolones or any antibiotic?

BACKGROUND: Delays in diagnosis of tuberculosis (TB) have been associated with previous use of antibiotics, and in particular fluoroquinolones (FQ), for suspected pulmonary infections. METHODS: We conducted a population-based cohort study with 2232 patients who had active TB between 1997 and 2006 (records obtained from the British Columbia Linked Health Databases). Patients with a record of an initial health care contact preceding the diagnosis of TB were identified for inclusion. Health care delay was defined as the time between initial health care contact and the initiation of anti-tuberculosis medication, and was compared between patients prescribed antibiotics and those not exposed to any antibiotics. RESULTS: A total of 1544 patients were included. After adjusting for covariates, average health care delay for patients exposed to antibiotics was found to be significantly greater, by a factor of 2.10 (95%CI 1.80-2.44), with a median delay of 41 days in the antibiotic group compared to 14 days in the non-antibiotic group. Sex, age, foreign-born status and socio-economic status were non-significant factors. Health care delay increased with the number of antibiotic courses received, but not with the type of antibiotic. CONCLUSIONS: Previous treatment with any antibiotic, and not only a FQ, is associated with a delay in TB diagnosis.

[Percutaneous treatment of symptomatic massive bile ducts stones after previous surgery with biliodigestive anastomosis -- report of three cases]. / Perkutánní resení symptomatické masivní hepatikolitiázy po predchozím operacním výkonu s biliodigestivní anastomózou -- tri kazuistiky.

PURPOSE: Presentation of our own experience with percutaneous treatment of symptomatic bile-duct stones like late complication in patients with biliodigestive anastomosis. METHOD: Three symptomatic female patients with biliodigestive anastomosis and acutely symptomatic with proven bile-duct stones above anastomosis were treated with initial percutaneous transhepatic drainage and later via percutaneous route using of endoscopic lithotryptor with special technique. RESULTS: All procedures were successful without complication, the patients are free of biliary symptoms in the long term. CONCLUSION: Percutaneous removal of bile-duct stones in patients with biliodigestive anastomosis is safe and effective method which can be used as an alternative to surgery.

[Spontaneous thrombosis of the splenic artery pseudoaneurysms]. / Spontánní trombóza pseudoaneuryzmatu slezinné tepny.

The authors demonstrate relatively rare case of evolution and spontaneous thrombosis of the postpancreatitic pseudoaneurysm of the splenic artery, which developed from a pancreatic pseudocyst. The miniinvasive therapeutic approach to the pancreatic pseudoaneurysms is discussed.

[Comparison of coated and bare metallic stents in inoperable carcinomas of the oesophagus and cardia]. / Srovnání potazených a nepotazených kovových stentu inoperabilních karcinomu jícnu a kardie.

INTRODUCTION AND AIM: The authors discuss paliative treatment using coated and bare metallic stents in a prospective randomized study for inoperable oesophageal carcinomas. The aim of this study is to assess the following parameters in both treatment groups: duration of the stents functionality, survival rates, complications rates and histological findings. METHODS: From 1999 to 2003, the total of 60 patients with oesophageal and cardial carcinomas were randomized. They had either bare (N-31 subjects) or coated (P-29 subjects) stents introduced. The patients were followed-up at one-month intervals. RESULTS: No statistical differences between the groups were found when the above parameters were assessed. DISCUSSION: The complications rate depended on the patients survival period in both stent types. Survival rates depended on the disease stage of the local tumorous process and on the individual patient's condition prior to the treatment. CONCLUSION: The study showed that the metallic selfexpandible stents treatment method may become a widely used paliative procedure in patients with malignant dysphagia, however, it has not proved any differences in complication rates depending on the stent coating.

[Endoscopic solution of iatrogenic lesion of oesophagus]. / Endoskopické resení iatrogenního poskození jícnu.

The case report dissertates upon successful treatment of iatrogenic perforation of distal oesophagus with subcutaneous emphysema, pneumoperitoneum and pneumomediastinum. The endoclips and classic conservative treatment were used in therapy. The patient was treated 3 hours after the injury, no early or late complications related to perforation were noted.

High-light stress and photoprotection in Umbilicaria antarctica monitored by chlorophyll fluorescence imaging and changes in zeaxanthin and glutathione.

The effect of high light on spatial distribution of chlorophyll (Chl) fluorescence parameters over a lichen thallus (Umbilicaria antarctica) was investigated by imaging of Chl fluorescence parameters before and after exposure to high light (1500 micro mol m (-2) s (-1), 30 min at 5 degrees C). False colour images of F (V)/F (M) and Phi (II) distribution, taken over thallus with 0.1 mm (2) resolution, showed that maximum F (V)/F (M) and Phi (II) values were located close to the thallus centre. Minimum values were typical for thallus margins. After exposure to high light, a differential response of F (V)/F (M) and Phi (II) was found. The marginal thallus part exhibited a loss of photosynthetic activity, manifested as a lack of Chl fluorescence signal, and close-to-centre parts showed a different extent of F (V)/F (M) and Phi (II) decrease. Subsequent recovery in the dark led to a gradual return of F (V)/F (M) and Phi (II) to their initial values. Fast (30 min) and slow (1 - 22 h) phase of recovery were distinguished, suggesting a sufficient capacity of photoprotective mechanisms in U. antarctica to cope with low-temperature photoinhibition. Glutathione and xanthophyll cycle pigments were analyzed by HPLC. High light led to an increase in oxidized glutathione (GSSG), and a conversion of violaxanthin to zeaxanthin, expressed as their de-epoxidation state (DEPS). The responses of GSSG and DEPS were reversible during subsequent recovery in the dark. GSSG and DEPS were highly correlated to non-photochemical quenching (NPQ), indicating involvement of these antioxidants in the resistance of U. antarctica to high-light stress. Heterogeneity of Chl fluorescence parameters over the thallus and differential response to high light are discussed in relation to thallus anatomy and intrathalline distribution of the symbiotic alga Trebouxia sp.

[Dysphagia in patients with disorders of the nervous system--comparison of a nasogastric tube with percutaneous endoscopic gastrostomy]. / Dysfagie u nemocných s poruchou nervového systému--srovnání nazogastrické sondy s perkutánní endoskopickou gastrostomií.

Dysphagia is frequently encountered in patients with acute affections of the nervous system (cerebrovascular attacks, craniocerebral injuries) and in chronic nervous diseases (amyotrophic lateral sclerosis, Parkinson s disease, dementia). To these patients enteral nutrition must be administered. If the perspective of dysphagia is short (several days) then nutrition by a nasogastric tube is fully indicated and sufficient. In cases of more prolonged dysphagia and in patients with a long perspective of dysphagia percutaneous endoscopic gastrostomy (PEG) is indicated. Both these methods of enteral nutrition have their advantages and disadvantages which are manifested in different ways in patients with disorders of the nervous system. The authors compared 62 patients hospitalized in the course of 4.5 years at the neurological department who had PEG with 72 patients who had nasogastric tubes and were hospitalized at the neurological intensive care unit in the course of one year. The authors evaluated the different indications for application, the incidence of complications and the advantages and disadvantages of the two methods.

[Indications for percutaneous endoscopic gastrostomy in patients with disorders of the nervous system]. / Indikace perkutánní endoskopické gastrostomie u nemocných s poruchou nervového systému.

Percutaneous endoscopic gastrostomy (PEG) is an efficient endoscopic method that ensures enteral nutrition for a longer period of time in patients who cannot take food per os. This method is also indicated in patients suffering from disorders of the central or peripheral nervous system which developed suddenly, such as a stroke or craniocerebral injuries, or gradually, such as amyotrophic lateral sclerosis (ALS), dementia, and multiple sclerosis. It has become common practice in the cooperation between neurologists and a gastroenterologists to use PEG in patients hospitalized in a neurological ward with encephalomalacy and haemorrhage, or craniocerebral injuries (after the patient recovers from the acute stage of the disease and is transferred to a neurological ICU), as well as in patients with ALS in a progressive stage. We gradually extend the indications of PEG for other patients with neurological disorders such as patients suffering from dementia, progressive multiple sclerosis, Parkinson's disease, and progressive polyneuropathy. Of 62 patients hospitalized in a neurological ward during a period of 4.5 years, 56 patients suffered from sudden disorders of the nervous system (strokes and craniocerebral injuries) and 6 patients had gradually progressing neurological diseases (ALS, multiple sclerosis, Parkinson's disease, dementia, and polyneuropathy).

Novel dystrophin mutations revealed by analysis of dystrophin mRNA: alternative splicing suppresses the phenotypic effect of a nonsense mutation.

The complete dystrophin mRNA sequence has been analyzed in 20 Duchenne muscular dystrophy and Becker muscular dystrophy patients. In 13 cases, deletions in mRNA were detected using reverse transcription-polymerase chain reaction and in another seven cases, point mutations were found using the protein truncation test. Sixteen patients diagnosed with Duchenne muscular dystrophy showed the presence of deletions or of nonsense point mutations. From four patients with the Becker muscular dystrophy phenotype, three cases were associated with deletions conserving the translational frame and one was associated with a nonsense mutation E1110X. In the case of the E1110X mutation, an alternative splicing of dystrophin mRNA (3485-3640del) was detected in this patient which included the E1110X mutation site (nucleotide 3536) and did not change the translation reading frame. Individual nonsense point mutations were characterized by sequence analysis, which showed five novel mutations with respect to those reported in the Cardiff Human Gene Mutation Database http://uwcm.web.cf.ac.uk/uwcm/mg/hgmd0.html and the Leiden muscular dystrophy pages http://www.dmd.nl/.