Induction of tier-2 neutralizing antibodies in mice with a DNA-encoded HIV envelope native like trimer

HIV Envelope (Env) is the main vaccine target for induction of neutralizing antibodies. Stabilizing Env into native-like trimer (NLT) conformations is required for recombinant protein immunogens to induce autologous neutralizing antibodies(nAbs) against difficult to neutralize HIV strains (tier-2) in rabbits and non-human primates. Immunizations of mice with NLTs have generally failed to induce tier-2 nAbs. Here, we show that DNA-encoded NLTs fold properly in vivo and induce autologous tier-2 nAbs in mice. DNA-encoded NLTs also uniquely induce both CD4 + and CD8 + T-cell responses as compared to corresponding protein immunizations. Murine neutralizing antibodies are identified with an advanced sequencing technology. The structure of an Env-Ab (C05) complex, as determined by cryo-EM, identifies a previously undescribed neutralizing Env C3/V5 epitope. Beyond potential functional immunity gains, DNA vaccines permit in vivo folding of structured antigens and provide significant cost and speed advantages for enabling rapid evaluation of new HIV vaccines.

Intradermal delivery of a synthetic DNA vaccine protects macaques from Middle East respiratory syndrome coronavirus

Emerging coronaviruses from zoonotic reservoirs, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have been associated with human-to-human transmission and significant morbidity and mortality. Here, we study both intradermal and intramuscular 2-dose delivery regimens of an advanced synthetic DNA vaccine candidate encoding a full-length MERS-CoV spike (S) protein, which induced potent binding and neutralizing antibodies as well as cellular immune responses in rhesus macaques. In a MERS-CoV challenge, all immunized rhesus macaques exhibited reduced clinical symptoms, lowered viral lung load, and decreased severity of pathological signs of disease compared with controls. Intradermal vaccination was dose sparing and more effective in this model at protecting animals from disease. The data support the further study of this vaccine for preventing MERS-CoV infection and transmission, including investigation of such vaccines and simplified delivery routes against emerging coronaviruses.

In vivo delivery of synthetic DNA-encoded antibodies induces broad HIV-1-neutralizing activity

Interventions to prevent HIV-1 infection and alternative tools in HIV cure therapy remain pressing goals. Recently, numerous broadly neutralizing HIV-1 monoclonal antibodies (bNAbs) have been developed that possess the characteristics necessary for potential prophylactic or therapeutic approaches. However, formulation complexities, especially for multiantibody deliveries, long infusion times, and production issues could limit the use of these bNAbs when deployed, globally affecting their potential application. Here, we describe an approach utilizing synthetic DNA-encoded monoclonal antibodies (dmAbs) for direct in vivo production of prespecified neutralizing activity. We designed 16 different bNAbs as dmAb cassettes and studied their activity in small and large animals. Sera from animals administered dmAbs neutralized multiple HIV-1 isolates with activity similar to that of their parental recombinant mAbs. Delivery of multiple dmAbs to a single animal led to increased neutralization breadth. Two dmAbs, PGDM1400 and PGT121, were advanced into nonhuman primates for study. High peak-circulating levels (between 6 and 34 μg/ml) of these dmAbs were measured, and the sera of all animals displayed broad neutralizing activity. The dmAb approach provides an important local delivery platform for the in vivo generation of HIV-1 bNAbs and for other infectious disease antibodies.

‘Hypertension multiple’: Patients’ experiential knowledge concept of symptoms and care required, and its implications for public health

Patients' conceptualisations of their disease do not always correspond to the biomedical definitions. Patients make sense of conditions by drawing on embodied experiences, beliefs circulating in their environments and information gathered from a variety of sources. Discrepancy between biomedical and patients' conceptualisations is problematic as it can affect treatment adherence, access to care, patient-provider communication and quality of patient experience. This is particularly the case for hypertension, an ‘invisible disease' that gives rise to various lay conceptions and practices. We examine how the disease is made ‘real' for Filipino hypertensive patients and the role their embodied experiences play in apprehending the chronicity of hypertension and in shaping care-related practices.

Drawing from interview and focus group data from hypertensive patients in low-income communities in the Philippines, and on Annemarie Mol's notion of ‘multiplicity', the ‘symptom' plays a key role in the ways in which participants self-manage ‘hypertension'. Hypertension is a ‘multiple' condition that is understood and enacted differently by people who rely on their own experiential knowledge and ‘symptoms' to define its nature and act accordingly to maintain health. Their ‘symptoms' may or may not correspond with the biomedical view of hypertension, leading to a non-chronic view of hypertension that informs the decision (not) to take maintenance medications regularly.

These findings have consequences for health communications and primary care. Failing to account for this ‘multiplicity' can also negatively impact experiences of care if patients feel that their embodied experiences are dismissed as less legitimate than biomedical indicators of the disease. Clinicians and public health officials must emphasize educational efforts that aim to address divergent views of noncommunicable diseases while respecting, listening to, and accounting for patients' experiential knowledge.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

First Record of Invasive Tawny Crazy Ant Nylanderia fulva (Mayr) (Hymenoptera: Formicidae) in Continental Ecuador and Notes on Its Ecology in Sugarcane Crops

We report the first known record of the tawny crazy ant Nylanderia fulva (Mayr) in continental Ecuador. In addition, we describe the mutualistic association between ants and white aphids Melanaphis sacchari (Zehntner) in a sugarcane crop. Finally, we highlight the necessity to carry out studies of this nature due to an increasing number of invasive ant species in Ecuador and their potential damage to agricultural and natural ecosystems.

A framework for automated conflict detection and resolution in medical guidelines

Common chronic conditions are routinely treated following standardised procedures known as clinical guidelines. For patients suffering from two or more chronic conditions, known as multimorbidity, several guidelines have to be applied simultaneously, which may lead to severe adverse effects when the combined recommendations and prescribed medications are inconsistent or incomplete. This paper presents an automated formal framework to detect, highlight and resolve conflicts in the treatments used for patients with multimorbidities focusing on medications. The presented extended framework has a front-end which takes guidelines captured in a standard modelling language and returns the visualisation of the detected conflicts as well as suggested alternative treatments. Internally, the guidelines are transformed into formal models capturing the possible unfoldings of the guidelines. The back-end takes the formal models associated with multiple guidelines and checks their correctness with a theorem prover, and inherent inconsistencies with a constraint solver. Key to our approach is the use of an optimising constraint solver which enables us to search for the best solution that resolves/minimises conflicts according to medication efficacy and the degree of severity in case of harmful combinations, also taking into account their temporal overlapping. The approach is illustrated throughout with a real medical example.

In Vivo Delivery of a DNA-Encoded Monoclonal Antibody Protects Non-human Primates against Zika Virus

Zika virus (ZIKV) infection is endemic to several world regions, and many others are at high risk for seasonal outbreaks. Synthetic DNA-encoded monoclonal antibody (DMAb) is an approach that enables in vivo delivery of highly potent mAbs to control infections. We engineered DMAb-ZK190, encoding the mAb ZK190 neutralizing antibody, which targets the ZIKV E protein DIII domain. In vivo-delivered DMAb-ZK190 achieved expression levels persisting >10 weeks in mice and >3 weeks in non-human primate (NHPs), which is protective against ZIKV infectious challenge. This study is the first demonstration of infectious disease control in NHPs following in vivo delivery of a nucleic acid-encoded antibody, supporting the importance of this new platform.

Phonon localization in heat conduction

Nondiffusive phonon thermal transport, extensively observed in nanostructures, has largely been attributed to classical size effects, ignoring the wave nature of phonons. We report localization behavior in phonon heat conduction due to multiple scattering and interference events of broadband phonons, by measuring the thermal conductivities of GaAs/AlAs superlattices with ErAs nanodots randomly distributed at the interfaces. With an increasing number of superlattice periods, the measured thermal conductivities near room temperature increased and eventually saturated, indicating a transition from ballistic to diffusive transport. In contrast, at cryogenic temperatures the thermal conductivities first increased but then decreased, signaling phonon wave localization, as supported by atomistic Greenșs function simulations. The discovery of phonon localization suggests a new path forward for engineering phonon thermal transport.

DMAb inoculation of synthetic cross reactive antibodies protects against lethal influenza A and B infections

Influenza virus remains a significant public health threat despite innovative vaccines and antiviral drugs. A major limitation to current vaccinations and therapies against influenza virus is pathogenic diversity generated by shift and drift. A simple, cost-effective passive immunization strategy via in vivo production of cross-protective antibody molecules may augment existing vaccines and antiviral drugs in seasonal and pandemic outbreaks. We engineered synthetic plasmid DNA to encode two novel and broadly cross-protective monoclonal antibodies targeting influenza A and B. We utilized enhanced in vivo delivery of these plasmid DNA-encoded monoclonal antibody (DMAb) constructs and show that this strategy induces robust levels of functional antibodies directed against influenza A and B viruses in mouse sera. Mice receiving a single inoculation with anti-influenza A DMAb survive lethal Group 1 H1 and Group 2 H3 influenza A challenges, while inoculation with anti-influenza B DMAb yields protection against lethal Victoria and Yamagata lineage influenza B morbidity and mortality. Furthermore, these two DMAbs can be delivered coordinately resulting in exceptionally broad protection against both influenza A and B. We demonstrate this protection is similar to that achieved by conventional protein antibody delivery. DMAbs warrant further investigation as a novel immune therapy platform with distinct advantages for sustained immunoprophylaxis against influenza.

A novel innoculation technique involving the injection of antibody-producing plasmid DNA has shown to be effective against influenza in mice. The flu is responsible for up to half a million deaths each year and up to five million cases of severe disease, while also posing a substantial pandemic threat, even with our current repertoire of vaccines. A team of researchers led by Sarah Elliott and David Weiner of The Wistar Institute of Anatomy and Biology, Philadelphia, developed potent plasmid-based constructs that, once injected, entered hosts’ cells and utilized cellular machinery to encode antibodies protective against a range of influenza A and B subtypes. DNA inoculation conferred acute protection from disease, with treated individuals also being immune to subsequent exposure. This approach warrants further investigation as an alternative technology for practical delivery of monoclonal antibody therapeutics.

158 FIRST LLAMA BORN BY IN VITRO FERTILIZATION

The aim was to transfer alpaca and llama embryos obtained by IVF into recipient llamas and evaluate pregnancy and birth rates. Gametes were collected from samples of ovaries and testes collected from a local abattoir. Cumulus-oocyte complexes (COC) were recovered by aspiration of ovarian follicles using a 5-mL syringe, where oocytes with at least 3 layers of cumulus cells and a homogenous cytoplasm were matured in TCM-199 supplemented with 10% FCS, FSH (0.1 IU), and oestradiol 17β for 30 and 36 h with 5% CO2 in air, for alpaca and llama, respectively. After the maturation time, COC were placed in FERT-TALP solution 30 min before in vitro insemination with epididymal sperm of alpaca and llama as appropriate, the sperm were selected by swim-up method with centrifuging twice in 2 mL of SPERM-TALP supplemented with 6 mg mL−1 of fatty-free BSA, in an incubator with 5% CO2 in air set at 39°C for 45 min, oocytes were co-incubated with sperm concentration of 3 × 106 mL−1 for 18 to 20 h at 39°C with 5% CO2 in air. The IVF was carried out the day of ovulation induction of recipients. A group of 15 morphologically intact Day-8 blastocysts derived from in vitro culture with SOF serum were transferred nonsurgically into the uterine horn ipsilateral to the corpus luteum of 15 synchronized recipient llamas with an intravaginal device (controlled internal drug release) for 8 days. Then, 6 days after controlled internal drug release removal, ovulation was induced in recipients with the application of 1 mL of GnRH with previous ultrasound confirmation of the presence of a dominant follicle greater than 7 mm in diameter. Nine alpaca blastocysts and 6 llama blastocysts were transferred. The pregnancy rate was assessed by ultrasound at 45 days after transfer. The results obtained were as follows: for pregnancy rate, 33.3% (3/9) and 50% (3/6) for alpaca and llama embryos, respectively; for birth rate, 0.0% (0/9) and 16.7% (1/6) for alpaca and llama embryos, respectively. An alpaca fetus and 2 llama fetuses were aborted between 7 and 10 months of pregnancy, and only a llama gestation ended successfully, producing the first birth of the world of a llama bred by IVF in South American camelids, demonstrating that it is possible to obtain viable offspring in these species using this biotechnology.

Inactivating the infralimbic but not prelimbic medial prefrontal cortex facilitates the extinction of appetitive Pavlovian conditioning in Long-Evans rats

The infralimbic medial prefrontal cortex (IL) has been posited as a common node in distinct neural circuits that mediate the extinction of appetitive and aversive conditioning. However, appetitive extinction is typically assessed using instrumental conditioning procedures, whereas the extinction of aversive conditioning is customarily studied using Pavlovian assays. The role of the IL in the extinction of appetitive Pavlovian conditioning remains underexplored. We investigated the involvement of the IL and prelimbic medial prefrontal cortex (PrL) in appetitive extinction in Pavlovian and instrumental conditioning assays in male, Long-Evans rats. Following acquisition, a gamma-aminobutyric acid agonist solution (0.03 nmol muscimol; 0.3 nmol baclofen; 0.3 μl/side) was bilaterally microinfused into the IL or PrL to pharmacologically inactivate each region before the first extinction session. Compared to saline, PrL inactivation did not affect the acquisition of extinction or the recall of extinction memory 24-h later. IL inactivation caused a more rapid extinction of Pavlovian conditioning, but had no effect on the extinction of instrumental conditioning or extinction recall. IL inactivation during a Pavlovian conditioning session in which conditioned stimulus (CS) trials were paired with sucrose did not affect CS-elicited behaviour, but increased responding during intervals that did not contain the CS. The same manipulation did not impact lever pressing for sucrose. These findings suggest that the IL may normally maintain Pavlovian conditioned responding when an anticipated appetitive CS is unexpectedly withheld, and that this region has distinct roles in the expression of Pavlovian conditioning when an appetitive unconditioned stimulus is either presented or omitted.

Circadian insights into dopamine mechanisms

Almost every physiological or behavioral process in mammals follows rhythmic patterns, which depend mainly on a master circadian clock located in the hypothalamic suprachiasmatic nucleus (SCN). The dopaminergic (DAergic) system in the brain is principally implicated in motor functions, motivation and drug intake. Interestingly, DA-related parameters and behaviors linked to the motivational and arousal states, show daily rhythms that could be regulated by the SCN or by extra-SCN circadian oscillator(s) modulating DAergic systems. Here we examine what is currently understood about the anatomical and functional central multi-oscillatory circadian system, highlighting how the main SCN clock communicates timing information with other brain clocks to regulate the DAergic system and conversely, how DAergic cues may have feedback effects on the SCN. These studies give new insights into the role of the brain circadian system in DA-related neurologic pathologies, such as Parkinson's disease, attention deficit/hyperactive disorder and drug addiction.

Deltamethrin resistance in the sea louse Caligus rogercresseyi (Boxhall and Bravo) in Chile: bioassay results and usage data for antiparasitic agents with references to Norwegian conditions

The sea louse Caligus rogercresseyi is a major threat to Chilean salmonid farming. Pyrethroids have been used for anticaligus treatments since 2007, but have shown reduced effect, most likely due to resistance development. Pyrethroid resistance is also a known problem in Lepeophtheirus salmonis in the Northern Hemisphere. This study describes the development of deltamethrin resistance in C. rogercresseyi based on bioassays and usage data for pyrethroids in Chilean aquaculture. These results were compared to bioassays from L. salmonis from Norway and to Norwegian usage data. Available deltamethrin bioassay results from 2007 and 2008, as well as bioassays from Norway, were collected and remodelled. Bioassays were performed on field-collected sea lice in region X in Chile in 2012 and 2013. Bioassays from 2007 were performed prior to the introduction of pyrethroids to the Chilean market. Both the results from 2008 and 2012 showed an increased resistance. Increased pyrethroid resistance was also indicated by the increased use of pyrethroids in Chilean aquaculture compared with the production of salmonids. A similar trend was seen in the Norwegian usage data. The bioassay results from Chile from 2012 and 2013 also indicated a difference in the susceptibility to deltamethrin between male and female caligus.

Viral agents causing lower respiratory tract infections in hospitalized children: evaluation of the Speed-Oligo® RSV assay for the detection of respiratory syncytial virus

Respiratory syncytial virus (RSV) is the viral agent which is more frequently involved in lower respiratory tract infections (LRTIs) in infants under 1 year of age in developed countries. A new oligochromatographic assay, Speed-Oligo® RSV, was designed and optimized for the specific detection and identification of RSV subtypes A and B. The test was evaluated in 289 clinical samples from 169 hospitalized children using an immunochromatography (IC) test, virus isolation by culture, and an in-house real-time polymerase chain reaction (RT-PCR). Other viruses causing LRTIs were investigated by cell culture or PCR-based tests. Sixty-two patients were infected by RSV (36.7%). In addition, adenovirus, influenza B, parainfluenza 2, and human metapneumovirus were detected in rates ranging from 5 to 8%. A proportion of 10.1% of the patients had mixed infections. The sensitivity, specificity, and positive and negative predictive values were, respectively, 94.9, 99.4, 98.9, and 97.4% for Speed-Oligo® RSV, 92.9, 96.3, 92.9, and 96.3% for RT-PCR/RSV, and 58.4, 98.1, 93.3, and 82.6% for IC. Our rates of viral detection and co-infection were similar to those of previously reported series. Finally, we find that Speed-Oligo® RSV is a rapid and easy-to-perform technique for the detection of RSV and the identification of subtypes A and B.

Dimorphic effects of leptin on the circadian and hypocretinergic systems of mice

The hormone leptin controls food intake and body weight through its receptor in the hypothalamus, and may modulate physiological functions such as reproduction, sleep or circadian timing. In the present study, the effects of leptin on the resetting of the circadian clock, the hypothalamic suprachiasmatic nucleus (SCN) and on the activity of the hypocretinergic system were examined in vivo, with comparative analysis between male and female mice. A single leptin injection (5 mg/kg) at both the onset and offset of the activity period did not alter locomotion of mice housed under a 12 : 12 h light/dark cycle and did not shift the circadian behavioral rhythm of mice housed in constant darkness. By contrast, leptin potentiated the phase-shifting effect of a 30-min light-pulse on behavioural rhythms during the late subjective night, although only in females. This was accompanied by a higher induction of the clock genes Per1 and Per2 in the SCN. A 2-week chronic exposure to a physiological dose of leptin (100 μg/kg per day) decreased locomotor activity, expression of hypocretin receptor 1 and 2, as well as the number of hypocretin-immunoreactive neurones only in female mice, whereas the number of c-fos-positive hypocretinergic neurones was reduced in both genders. These results highlight a dimorphic effect of leptin on the hypocretinergic system and on the response of the circadian clock to light. Leptin may thus modulate the sleep/wake cycle and circadian system beside its well-established action on food intake and regulation of body weight.

Current antiviral combination therapy for chronic hepatitis C patients who failed to interferon alfa-based treatment

WHAT IS KNOWN AND OBJECTIVE

Interferon-alfa-based therapy is effective in the treatment of Hepatitis C. However, some patients fail to respond and others relapse, after initially responding. Our objective was to assess the efficacy, safety and predictive factors for sustained virological response (SVR) to peginterferon plus ribavirin in chronic hepatitis C patients who failed to interferon-alfa (IFNα)-based therapy.

METHODS

Seventy-five consecutive patients who failed to IFNα-based therapy were retreated with peginterferon plus ribavirin. Of these patients, 85% were infected by genotype 1. The primary endpoint was SVR.

RESULTS AND DISCUSSION

Of 75 non-responder (n = 54) or relapser patients (n = 21), 50 were previously treated with IFNα-monotherapy and 25 with IFNα plus ribavirin. Global SVR rate was 41.3%: for patients re-treated with IFNα the response was 48% whilst for those retreated with IFNα plus ribavirin, it was 28%. For previous non-responders the SVR rate was 37% and for relapsers it was 52.4%.

WHAT IS NEW AND CONCLUSION

Retreatment with peginterferon plus ribavirin is an effective option for some chronic hepatitis C non-responder or relapser patients. Higher SVR rate was achieved in relapsers and in those patients who received IFNα monotherapy previously.

Hepatic fibrosis in patients with chronic hepatitis C assessed by transient elastography: implications for determining the efficacy of antiviral therapy

BACKGROUND

The efficacy of combination therapy with peginterferon plus ribavirin to eradicate viral infection in patients with chronic hepatitis C (CHC) is well established; moreover, it is able to arrest or even reverse liver fibrosis.

AIMS

To analyze the measurements of hepatic stiffness as an index of liver fibrosis using transient elastography (TE) in patients who underwent a sustained virological response (SVR) during long-term follow-up; comparing the changes in the severity of fibrosis with non-responders patients.

MATERIAL AND METHODS

After hepatic fibrosis was studied in three patients with CHC who underwent a SVR during long-term follow up, a prospective study was initiated in 24 patients with CHC who received combination therapy to compare the evolution of fibrosis in those with SVR and those who were non-responders. The genotype of hepatitis C virus (HCV) and the degree of viremia were determined. METAVIR scoring system was used for liver fibrosis. Hepatic stiffness was measured by TE.

RESULTS

Of the initial three patients pre-treatment liver biopsies revealed active disease and fibrosis (stage 3) in two and mild fibrosis (stage 1) in one. After several years of follow up serum AST/ALT levels were normal and HCV RNA was undetectable in each case; in contrast to the baseline histological assessments of fibrosis, values for hepatic stiffness (3.4-6.9 KPa) were compatible with an absence of any appreciable hepatic fibrosis. In the prospective study, 8 patients underwent a SVR and 16 were non-responders. TE indicated that the severity of hepatic fibrosis in the SVR group improved in 7 (88%) patients, whereas in the non-responder it improved in only 4 (25%) (p < 0.05). The difference between development of severe fibrosis (F > or = 3) in responders and non-responders was not significant (p = 0.23), possibly due to the small sample size.

CONCLUSIONS

Regression of hepatic fibrosis appears to be common in patients with CHC who undergo a SVR. TE is a simple non-invasive technique that enables multiple assessments of the severity of hepatic fibrosis to be made efficiently during long-term follow-up of patients with CHC who receive combination antiviral therapy.

Behavioural food anticipation in clock genes deficient mice: confirming old phenotypes, describing new phenotypes

Animals fed daily at the same time exhibit circadian food-anticipatory activity (FAA), which has been suggested to be driven by one or several food-entrainable oscillators (FEOs). FAA is altered in mice lacking some circadian genes essential for timekeeping in the main suprachiasmatic clock (SCN). Here, we confirmed that single mutations of clock genes Per1(-/-) and Per2(Brdm1) alter FAA expression in constant darkness (DD) or under a light-dark cycle (LD). Furthermore, we found that Per1(-/-);Per2(Brdm1) and Per2(Brdm1);Cry1(-/-) double mutant animals did not display a stable and significant FAA either in DD or LD. Interestingly, rescued behavioural rhythms in Per2(Brdm1);Cry2(-/-) mice in DD were totally entrained to feeding time and re-synchronized after phase-shifts of mealtime, indicating a higher SCN sensitivity to feeding cues. However, under an LD cycle and restricted feeding at midday, FAA in double Per2(Brdm1);Cry2(-/-) mutant mice was absent. These results indicate that shutting down one or two clock genes results in altered circadian meal anticipation. Moreover, we show that in a genetically rescued SCN clock (Per2(Brdm1);Cry2(-/-)), food is a powerful zeitgeber to entrain behavioural rhythms, leading the SCN to be more sensitive to feeding cues than in wild-type littermates.

Transient elastography to assess hepatic fibrosis in primary biliary cirrhosis

BACKGROUND

Liver stiffness measurements may have potential for detecting and monitoring hepatic fibrosis in chronic liver disease.

AIM

To study the detection, quantification and progression of hepatic fibrosis in primary biliary cirrhosis by liver stiffness measurements.

METHODS

Liver stiffness measurements were generated in 80 patients with primary biliary cirrhosis by applying transient elastography; however, as there were 55 with liver biopsy, histological stage (METAVIR) and liver stiffness measurements were compared only in these 55 patients. The efficiency of liver stiffness measurements in predicting stage of fibrosis was determined from the area under receiver operating characteristics curve analysis.

RESULTS

Of the 80 patients included, 91, 4% were women and their mean age was 56 +/- 12 (s.d.) years. A significant correlation was found (P < 0.05) between histological fibrosis stage (METAVIR) and liver stiffness measurements. The values obtained from area under receiver operating characteristic curve analysis of liver stiffness measurement data were 0.89 for F > 2 and 0.96 for F = 4. Liver stiffness measurements were 9.0 +/- 5.3 and 7.9 +/- 6.0 kPa for patients followed up more than 5 years and less than 5 years, respectively (P > 0.05).

CONCLUSIONS

In patients with primary biliary cirrhosis, median values of liver stiffness measurements correlated with histological severity of hepatic fibrosis. Liver stiffness measurements appear to be promising for liver fibrosis detection and quantification, as well as monitoring its progression, in patients with primary biliary cirrhosis. The progression rate of hepatic fibrosis in our primary biliary cirrhosis patients appears to be slow.

[Effect of an intensive nutritional treatment in nutritional status of head and neck cancer patients in stages III and IV]

OBJECTIVE

Malnutrition and accelerated weight loss are frequent secondary diagnosis in patients with cancer. Head and neck cancer (H & N Cancer) affects nutritional status because of the tumor type and localization. The aim of the study was to assess the effect of an intensive nutritional treatment (INT) on nutritional status of H & N cancer patients, stages III and IV and to compare that with a historical control whose nutritional treatment was conventional (CT).

METHODS

All patients were nutritionally assessed before oncological treatment started (anthropometrical, biochemical, and dietetically). A nutritional feeding plan according to their nutritional personal need was calculated. In case it was impossible to cover all the nutritional requirements orally, a feeding tube was placed. Nutritional follow up was performed each 21 days, during their oncological treatment in four occasions. The results obtained were compared with those obtained from the patients who received the CT that consisted only in nutritional counseling by the attending physician; the statistical test used was Mann Whitney U test.

RESULTS

The INT was associated with maintenance of the nutritional status along their oncological treatment. The statistical significant parameters were: weight 55 to 47 kg in the CT group vs 59 a 58 kg in the INT group (p < 0.0001), and hemoglobin: from 13 to 11 g/dl in the CT group vs 14 to 13 g/dl in the INT group (p < 0.002) as the most important ones. In the rest of the data we can observe a clear tendency of increasing the nutrition parameters in patients the INT group, while in the CT group, they showed a persistent decrease.

CONCLUSION

We concluded that patients who received the INT as part of their oncological treatment deteriorated less their nutritional status than those who received a CT.

Daily meal timing is not necessary for resetting the main circadian clock by calorie restriction

In rodents, entrainment and/or resetting by feeding of the central circadian clock, the suprachiasmatic nucleus (SCN), is more efficient when food cues arise from a timed calorie restriction. Because timed calorie restriction is associated with a single meal each day at the same time, its resetting properties on the SCN possibly depend on a combination of meal time-giving cues and hypocaloric conditions per se. To exclude any effect of daily meal timing in resetting by calorie restriction, the present study employed a model of ultradian feeding schedules, divided into six meals with different durations of food access (6 x 8-min versus 6 x 12-min meal schedule) every 4 h over the 24-h cycle. The effects of such an ultradian calorie restriction were evaluated on the rhythms of wheel-running activity (WRA) and body temperature (Tb) in rats. The results indicate that daily/circadian rhythms of WRA and Tb were shifted by a hypocaloric feeding distributed in six ultradian short meals (i.e. 6 x 8-min meal schedule), showing both phase advances and delays. The magnitude of phase shifts was positively correlated with body weight loss and level of day-time behavioural activity. By contrast, rats fed daily with six ultradian meals long enough (i.e. 6 x 12-min meal schedule) to prevent body weight loss, showed only small, if any, phase shifts in WRA and Tb rhythms. The results obtained reveal the potency of calorie restriction to reset the SCN clock without synchronisation to daily meal timing, highlighting functional links between metabolism, calorie restriction and the circadian timing system.

Systematic review: the adverse effects of sodium phosphate enema

BACKGROUND

Sodium-phosphate enemas are widely used to treat constipation, and are rarely associated with side effects.

AIM

A systematic review of the literature was conducted to identify the most common adverse effects of sodium-phosphate enemas and associated risk factors.

METHODS

A systematic search was conducted in Internet (MEDLINE), and the Cochrane Library, from January 1957 to March 2007.

RESULTS

A total of 761 references were identified initially, and 39 relevant papers were finally selected. The most common therapeutic indications included constipation (63%). Sixty-eight per cent of the patients having adverse effects had associated conditions, the most common being gastrointestinal motility disorders, cardiological diseases and renal failure. Virtually, all side effects were due to water and electrolyte disturbances. Most patients were under 18 years of age (66%) or older than 65 years (25%). A total of 12 deaths were found.

CONCLUSION

The main side effects caused by sodium phosphate enemas are water and electrolyte disturbances. The main risk factors are extreme age and associated comorbidity.

Images reproducibility of an electrical impedance tomography (EIT) prototype. Analysis of the EIT sensibility in rats in pathological in vivo conditions

The development of a 16 electrode-electrical impedance tomography (EIT) prototype to be applied in neurological fields such as epilepsy in rats has been previously reported. Approaching residual problems in order to improve its performance, this work reports results about changes made in the system hardware as follows: 1) replacing the current source demultiplexing circuit that could impact on a better spatial localization, and 2) a new current source design that increases the current amplitude up to 5 mA/sub rms/. System was evaluated by means of: a) image reproducibility starting from 4 test elements in homogeneous conditions; and b) spatial localization evaluation in conductivity perturbation conditions; this feature is evaluated too in preliminary acute in vivo experiments where an epileptic seizure is induced, and an impedance increase is expected. Results show a 95% of proper images for a) analysis. Spatial localization reports improvement up to 20% transversely and 5.5% longitudinally with regard to previous results. In vivo results are lack of interpretation due poor changes obtained in images. In order to conclude or not a reliable correlation between the perturbation measured and the seizure activity, a new definition of grey scale or other changes could be proposed.

Circadian clocks: setting time by food

In mammals, daily rhythms in behaviour and physiology are driven by a circadian timing system comprised, in a hierarchical way, of a master pacemaker in the suprachiasmatic nuclei (SCN) of the hypothalamus and of peripheral oscillators in most body cells. At the molecular level, in both the SCN and peripheral oscillators, the circadian clock mechanism is built from interconnected feedback loops in gene expression that operate in a cell-autonomous and self-sustained fashion. The SCN clock is mainly entrained by light/dark cycles. By contrast, peripheral oscillators can be strongly affected by daily feeding cycles, which have little effect on the phase of the SCN. However, when feeding schedules are coupled with a caloric restriction, behavioural and physiological circadian rhythms and gene expression in the SCN are shifted and/or entrained to meal-time. Moreover, the reward and motivational value of food can also be a potent synchroniser for the SCN clock. This suggests that energy metabolism and motivational properties of food can influence the clock mechanism of the SCN. Food-related cues may entrain clock genes of the SCN with a direct effect, or be mediated indirectly by another neural or peripheral site. In addition, there may be one or more oscillator sites that would play an integral role as a food-entrained oscillator (FEO), responsible for anticipation of meal-time. The site housing, or the network underlying, this putative FEO is still unknown. The aim of this review is to summarise our current knowledge of the central and peripheral circadian clocks and how they can be entrained by feeding at the physiological and molecular levels.

Restricted feeding schedules phase shift daily rhythms of c-Fos and protein Per1 immunoreactivity in corticolimbic regions in rats

Entrainment by daily restricted feeding schedules (RFS) produces food anticipatory activity (FAA) which involves motivational processes which may be regulated by corticolimbic structures and the nucleus accumbens. The present study aimed first to determine whether corticolimbic structures participate in the expression of FAA, therefore c-Fos immunoreactivity (Fos-IR) was employed as marker of neuronal activity. The second goal was to characterize diurnal rhythms of the clock protein protein Per1 (PER1) in corticolimbic structures and to determine the influence of RFS on the diurnal temporal pattern. Rats were maintained under RFS with food access for 2 h daily, a control group was fed ad libitum. Food entrainment produced a pattern of increased Fos-IR during FAA and after mealtime in the two sub-regions of the nucleus accumbens (ACC), in the basolateral and central amygdala, in the bed nucleus of the stria terminalis (BNST), in the lateral septum (LS), in the prefrontal cortex (PFC), and in the paraventricular thalamic nucleus (PVT). No increased Fos-IR was observed in the hippocampus. Under ad libitum conditions all structures studied showed daily oscillations of PER1, excluding both amygdalar nuclei and the PFC. RFS shifted and set the daily peaks at zeitgeber time (ZT) 12 for both sub-regions in the accumbens, the hippocampus, lateral septum and PFC. RFS enhanced the amplitude at ZT12 of the BNST and shifted the peak of the PVT to ZT6. No changes were observed in the amygdalar nuclei. Present data indicate that cellular activation of corticolimbic structures is associated with behavioral events related to food anticipatory activity and that mealtime is a relevant signal that shifts daily oscillations of PER1 in corticolimbic structures. Data suggest a relevant role of corticolimbic structures as oscillators for FAA.

Transient elastography: a valid alternative to biopsy in patients with chronic liver disease

BACKGROUND

Transient elastography is a novel and non-invasive technique for the evaluation of fibrosis in chronic liver disease. Few studies that exist value the efficacy of transient elastography, mainly in hepatitis C virus-infected patients.

AIM

To evaluate the effectiveness, objectivity, reproducibility and safety of this technique.

METHODS

We included 103 consecutive patients who underwent a liver biopsy in the last 48 months with a wide spectrum of chronic liver diseases. Median stiffness value (expressed as kilopascals - kPa) was kept as representative of the liver elastic modulus. All biopsy specimens were analysed by the same pathologist according to the METAVIR scoring system.

RESULTS

Median value of stiffness in patients with mild or moderate fibrosis (FI and FII), and severe fibrosis or cirrhosis (FIII and FIV) was of 7, 4 +/- 5 and 16, 4 +/- 10 kPa, respectively, with a significant difference between them (P < 0.05). The areas under the receiver operating characteristic curves showed the optimal liver stiffness cut-off values for each group.

CONCLUSIONS

We found a positive correlation between the liver stiffness found by transient elastography and fibrosis stage on biopsy in all patients, independently of the liver disease aetiology. Transient elastography is an easy, quick to perform and safe non-invasive procedure, reliable for assessing liver fibrosis.