Kinetics of ventilation-induced changes in diaphragmatic metabolism by bilateral phrenic pacing in a piglet model

Citation: Breuer, T., Hatam, N., Grabiger, B., Marx, G., Behnke, B. J., Weis, J., . . . Bruells, C. S. (2016). Kinetics of ventilation-induced changes in diaphragmatic metabolism by bilateral phrenic pacing in a piglet model. Scientific Reports, 6, 10. doi:10.1038/srep35725Perioperative necessity of deep sedation is inevitably associated with diaphragmatic inactivation. This study investigated 1) the feasibility of a new phrenic nerve stimulation method allowing early diaphragmatic activation even in deep sedation and, 2) metabolic changes within the diaphragm during mechanical ventilation compared to artificial activity. 12 piglets were separated into 2 groups. One group was mechanically ventilated for 12 hrs (CMV) and in the second group both phrenic nerves were stimulated via pacer wires inserted near the phrenic nerves to mimic spontaneous breathing (STIM). Lactate, pyruvate and glucose levels were measured continuously using microdialysis. Oxygen delivery and blood gases were measured during both conditions. Diaphragmatic stimulation generated sufficient tidal volumes in all STIM animals. Diaphragm lactate release increased in CMV transiently whereas in STIM lactate dropped during this same time point (2.6 vs. 0.9 mmol L-1 after 5:20 hrs; p < 0.001). CMV increased diaphragmatic pyruvate (40 vs. 146 mu mol L-1 after 5:20 hrs between CMV and STIM; p < 0.0001), but not the lactate/pyruvate ratio. Diaphragmatic stimulation via regular electrodes is feasible to generate sufficient ventilation, even in deep sedation. Mechanical ventilation alters the metabolic state of the diaphragm, which might be one pathophysiologic origin of ventilator-induced diaphragmatic dysfunction. Occurrence of hypoxia was unlikely

Investigating the Prevalence of Intestinal Parasites in Immunocompromised Patients in Bushehr Province, Southwest Iran: A Conventional and Molecular Study [İran’ın Güneybatısındaki Bushehr Eyaletindeki İmmün Yetmezliği Olan Hastalarda Bağırsak Parazitlerinin Prevalansının Araştırılması: Konvansiyonel ve Moleküler Bir Çalışma]

Objective: The aim of this study was to determine the status of intestinal parasitic infections in immunocompromised patients in Bushehr province, southwest Iran by conventional and molecular methods. Methods: A total of 201 stool samples were collected from kidney transplant recipients, AIDS patients and patients under chemotherapy. Samples were collected from healthy people as the control group. The specimens were tested using various conventional methods. Polymerase chain reaction (PCR) testing was performed on samples identified as positive for Coccidia by direct microscopic examination. Results: Approximately 32.45% were infected with at least one type of intestinal parasite. The highest (46.8%) and lowest rates of infection (24%) were observed in AIDS and chemotherapy patients, respectively, while the infection rate of the control group was 16%. Isospora spp. and Cryptosporidium spp. were observed in all patient groups, and Sarcocystis spp. sporocysts were detected in one of the transplant recipients. All identified coccidia were confirmed by PCR. There was a significant relationship between the rate of intestinal parasite infection and certain variables. Conclusion: Given the potential risk of certain intestinal parasites in people with immune deficiency, it is recommended that diagnosis of parasitic infections in such patients be based on specific parasitological methods. Thus, it is advisable that physicians refer them to a parasitology laboratory prior to drug administration. Amaç: Bu çalışmanın amacı, İran’ın güneybatısındaki Bushehr eyaletindeki immün yetmezlikli hastalarda bağırsak paraziter enfeksiyonlarının durumunu konvansiyonel ve moleküler yöntemlerle belirlemektir. Yöntemler: Böbrek nakli alıcılarından, AIDS hastalarından ve kemoterapi alan hastalardan olmak üzere toplam 201 dışkı örneği toplandı. Kontrol grubu numuneleri sağlıklı insanlardan toplandı. Numuneler çeşitli konvansiyonel yöntemler kullanılarak test edildi. Polimeraz zincir reaksiyon (PZR) testi, doğrudan mikroskobik incelemelerde tespit edilen pozitif Coccidia örnekleri üzerinde yapıldı. Bulgular: Hastaların yaklaşık %32,45’i en az bir tür bağırsak paraziti ile enfekte olmuştu. En yüksek (%46,8) ve en düşük enfeksiyon oranı (%24) sırasıyla AIDS ve kemoterapi hastalarında görülürken, kontrol grubunun enfeksiyon oranı %16 idi. Isospora spp. ve Cryptosporidium spp. tüm hasta gruplarında ve Sarcocystis spp. sporokistleri ise transplant alıcılarından birinde tespit edildi. Tanımlanan tüm Coccidialar, PZR ile doğrulandı. Bağırsak parazitlerinin oranı ile bazı değişkenler arasında anlamlı bir ilişki mevcuttu. Sonuç: İmmün yetmezliği olan kişilerde bazı bağırsak parazitlerinin potansiyel riski göz önüne alındığında, paraziter enfeksiyonların spesifik parazitolojik yöntemlere dayanarak teşhis edilmesi önerilir. Bu nedenle, doktorların ilaç vermeden önce bu hastaları parazitoloji laboratuvarına yönlendirmeleri tavsiye edilir

Superior outcomes with Argatroban for heparin-induced thrombocytopenia: a Bayesian network meta-analysis

Background Argatroban, lepirudin, desirudin, bivalirudin, and danaparoid are commonly used to manage heparin-induced thrombocytopenia related complications. However, the most suitable drug for this condition still remains controversial. Aim of the review This Bayesian network meta-analysis study compared the most common anticoagulant drugs used in the management of heparin-induced thrombocytopenia. Method All clinical trials comparing two or more anticoagulant therapies for suspected or confirmed heparin-induced thrombocytopenia were considered for inclusion. Studies concerning the use of heparins or oral anticoagulants were not considered. Data concerning hospitalisation length, thromboembolic, major, and minor haemorrhagic events, and mortality rate were collected. The network analyses were made through the STATA routine for Bayesian hierarchical random-effects model analysis with standardised mean difference (SMD) and log odd ratio (LOR) effect measures. Results Data from a total of 4338 patients were analysed. The overall mean age was 62.31 ± 6.6 years old. Hospitalization length was considerably shorter in favour of the argatroban group (SMD: - 1.70). Argatroban evidenced the lowest rate of major (LOR: - 1.51) and minor (LOR: - 0.57) haemorrhagic events. Argatroban demonstrated the lowest rate of thromboembolic events (LOR: 0.62), and mortality rate (LOR: - 1.16). Conclusion Argatroban performed better overall for selected patients with HIT. Argatroban demonstrated the shortest hospitalization, and lowest rate of haemorrhages, thromboembolisms, and mortality compared to bivalirudin, lepirudin, desirudin, and danaparoid

Speckle tracking echography allows sonographic assessment of diaphragmatic loading

Introduction: Assessment of diaphragm function should ideally be assessed using magnetic twitch pressure or esophageal and gastric balloons. Conventional sonographic techniques as thickness and fractional thickening (FT), only provide limited insight in diaphragm function. Speckle tracking echocardiography allows reliable quantification of muscle function by tracking of grey patterns and their motion; strain as parameter of muscle deformation and strain rate as deformation velocity. Aim: To investigate whether speckle tracking can quantify loading of the diaphragm, superior to FT. Methods: 13 healthy volunteers underwent an inspiratory loading protocol with recording of transdiaphragmatic pressure (Pdi) and diaphragm electromyography (EMGdi). Inspiratory loading of 0 to 30% of maximal inspiratory pressure was applied in random order for 5 minutes per applied load. Diaphragmatic sonography was performed using a 2-4 MHz linear phased array transducer positioned at the right-lateral thoracic wall in the anterior axillary line longitudinal to the body axis. Ultrasound recordings of the diaphragm were made at the marked location during 10 seconds. Results: Increased inspiratory loading increased Pdi and EMGdi. Sonographic markers of contractility increased with incremental loading. Pdi correlated with strain (r=0.75; p=0.000) and strain rate (r=0.77; p=0.000). Contrarily, FT was not correlated with Pdi. Conclusion: Speckle tracking of the diaphragm can detect changes in diaphragmatic loading up to 30% of maximal inspiratory pressure. It might be a valuable tool to detect changes in loading in specific patient categories, including patients with acute respiratory failure and ventilated ICU patients

Transfusion-transmitted malaria : a systematic review and meta-analysis

Background : Malaria transmission through blood transfusion is an accidental but preventable cause of malaria infection and is increasingly becoming a matter of concern for blood transfusion services. This systematic review was conducted to provide a summary of evidence about the prevalence of Plasmodium infection in asymptomatic blood donors and the effectiveness of screening methods used based on the available literature. Methods : PRISMA guidelines were followed. Scopus, PubMed, Science Direct, and EMBASE were searched from 1982 to October 10, 2017. All peer-reviewed original research articles describing the prevalence of malaria parasitemia in blood donors with different diagnostic methods were included. The random-effects model was applied to assess the effects of heterogeneity among the selected studies. Incoherence and heterogeneity between studies were quantified by I2 index and Cochran's Q test. Publication and population bias was assessed with funnel plots and Egger's regression asymmetry test. All statistical analyses were performed using Stata (version 2.7.2). Results : Seventy-one studies from 21 countries, 5 continents, were included in the present systematic review. The median prevalence of malaria parasitemia among 984 975 asymptomatic healthy blood donors was 10.54%, 5.36%, and 0.38% by microscopy, molecular methods (polymerase chain reaction), and rapid diagnostic tests, respectively. The most commonly detected Plasmodium species was P. falciparum. Conclusions : This systematic review demonstrates that compared with other transfusion-linked infections, that is, HIV, HCV, and HBV, transfusion-transmitted malaria is one of the most significant transfusion-associated infections especially in Sub-Saharan Africa. Future work must aim to understand the clinical significance of transfusion-transmitted malaria in malaria-endemic settings.Publisher PDFPeer reviewe

Organic matter from Artic sea ice loss alters bacterial community structure and function

Continuing losses of multi-year sea ice (MYI) across the Arctic are resulting in first-year ice (FYI) dominating the Arctic ice pack. Melting FYI provides a strong seasonal pulse of dissolved organic matter (DOM) into surface waters; however, the biological impact of this DOM input is unknown. Here we show that DOM additions cause significant and contrasting changes in under-ice bacterioplankton abundance, production and species composition. Utilization of DOM was influenced by molecular size, with 10-100 kDa and >100 kDa DOM fractions promoting rapid growth of particular taxa, while uptake of sulfur and nitrogen-rich low molecular weight organic compounds shifted bacterial community composition. These results demonstrate the ecological impacts of DOM released from melting FYI, with wideranging consequences for the cycling of organic matter across regions of the Arctic Ocean transitioning from multi-year to seasonal sea ice as the climate continues to warm

LeishVet update and recommendations on feline leishmaniosis

Limited data is available on feline leishmaniosis (FeL) caused by Leishmania infantum worldwide. The LeishVet group presents in this report a review of the current knowledge on FeL, the epidemiological role of the cat in L. infantum infection, clinical manifestations, and recommendations on diagnosis, treatment and monitoring, prognosis and prevention of infection, in order to standardize the management of this disease in cats. The consensus of opinions and recommendations was formulated by combining a comprehensive review of evidence-based studies and case reports, clinical experience and critical consensus discussions. While subclinical feline infections are common in areas endemic for canine leishmaniosis, clinical illness due to L. infantum in cats is rare. The prevalence rates of feline infection with L. infantum in serological or molecular-based surveys range from 0 % to more than 60 %. Cats are able to infect sand flies and, therefore, they may act as a secondary reservoir, with dogs being the primary natural reservoir. The most common clinical signs and clinicopathological abnormalities compatible with FeL include lymph node enlargement and skin lesions such as ulcerative, exfoliative, crusting or nodular dermatitis (mainly on the head or distal limbs), ocular lesions (mainly uveitis), feline chronic gingivostomatitis syndrome, mucocutaneous ulcerative or nodular lesions, hypergammaglobulinaemia and mild normocytic normochromic anaemia. Clinical illness is frequently associated with impaired immunocompetence, as in case of retroviral coinfections or immunosuppressive therapy. Diagnosis is based on serology, polymerase chain reaction (PCR), cytology, histology, immunohistochemistry (IHC) or culture. If serological testing is negative or low positive in a cat with clinical signs compatible with FeL, the diagnosis of leishmaniosis should not be excluded and additional diagnostic methods (cytology, histology with IHC, PCR, culture) should be employed. The most common treatment used is allopurinol. Meglumine antimoniate has been administered in very few reported cases. Both drugs are administered alone and most cats recover clinically after therapy. Follow-up of treated cats with routine laboratory tests, serology and PCR is essential for prevention of clinical relapses. Specific preventative measures for this infection in cats are currently not available

Investigation of Double-Band Electrophoretic Pattern of ITS-rDNA Region in Iranian Isolates of Leishmania Tropica

Background: Leishmania tropica is a genetically divergent species. Amplification of entire internal tran­scribed spacer (ITS) region of L. tropica isolates obtained from Bam district, one of the well known focus of anthroponotic cutaneous leishmaniasis) ACL( in Iran, revealed a double-band pat­tern in agarose gel electrophoresis. This study explains how this pattern occurs.Methods: Twenty seven L. tropica smear preparations were collected from Bam district, south east Iran, and eight L. major and one L. infantum smear preparations were gathered from Shiraz, south west Iran. Furthermore one L. major and one L. infantum cultured standard strains were tested using entire ITS-PCR to survey their electrophoretic pattern. The ITS sequences of L. tropica, L. major, and L. infantum already deposited in GenBank were analyzed. Analysis of GenBank sequences of L. tropica revealed two groups of sequences based on length size, one group having a 100 bp gap. Therefore, a new re­verse primer namely LITS-MG was designed to exclude this gap in PCR products.Results: Whole ITS fragment amplification resulted in a double-band pattern in all L. tropica cases, while a sharp single band was observed for L. infantum and L. major isolates. This result was correspond­ing to the result obtained from in silico analysis of GenBank sequences. Use of LITS-MG primer was expectedly resulted in a single band including ITS1, 5.8s and partial ITS2 product for L. tropica which is appropriate for following molecular studies such as sequencing or restriction analysis.Conclusion: Sequences analysis of GenBank L. tropica sequences and following practical laboratory tests revealed at least two alleles in L. tropica which were confirmed in Bam isolates. This especial double-band pattern is because of a 100 bp fragment difference within ITS-rDNA allele

Comparing springtime ice-algal chlorophyll a and physical properties of multi-year and first-year sea ice from the Lincoln Sea

With near-complete replacement of Arctic multi-year ice (MYI) by first-year ice (FYI) predicted to occur within this century, it remains uncertain how the loss of MYI will impact the abundance and distribution of sea ice associated algae. In this study we compare the chlorophyll a (chl a) concentrations and physical properties of MYI and FYI from the Lincoln Sea during 3 spring seasons (2010-2012). Cores were analysed for texture, salinity, and chl a. We identified annual growth layers for 7 of 11 MYI cores and found no significant differences in chl a concentration between the bottom first-year-ice portions of MYI, upper old-ice portions of MYI, and FYI cores. Overall, the maximum chl a concentrations were observed at the bottom of young FYI. However, there were no significant differences in chl a concentrations between MYI and FYI. This suggests little or no change in algal biomass with a shift from MYI to FYI and that the spatial extent and regional variability of refrozen leads and younger FYI will likely be key factors governing future changes in Arctic sea ice algal biomass. Bottom-integrated chl a concentrations showed negative logistic relationships with snow depth and bulk (snow plus ice) integrated extinction coefficients; indicating a strong influence of snow cover in controlling bottom ice algal biomass. The maximum bottom MYI chl a concentration was observed in a hummock, representing the thickest ice with lowest snow depth of this study. Hence, in this and other studies MYI chl a biomass may be under-estimated due to an under-representation of thick MYI (e.g., hummocks), which typically have a relatively thin snowpack allowing for increased light transmission. Therefore, we suggest the on-going loss of MYI in the Arctic Ocean may have a larger impact on ice–associated production than generally assumed