Biologists can equip animals with global positioning system (GPS) technology to obtain accurate (less than or equal to 30 m) locations that can be combined with sensor data to study animal behaviour ...and ecology. We provide the background of GPS techniques that have been used to gather data for wildlife studies. We review how GPS has been integrated into functional systems with data storage, data transfer, power supplies, packaging and sensor technologies to collect temperature, activity, proximity and mortality data from terrestrial species and birds. GPS ‘rapid fixing’ technologies combined with sensors provide location, dive frequency and duration profiles, and underwater acoustic information for the study of marine species. We examine how these rapid fixing technologies may be applied to terrestrial and avian applications. We discuss positional data quality and the capability for high-frequency sampling associated with GPS locations. We present alternatives for storing and retrieving data by using dataloggers (biologging), radio-frequency download systems (e.g. very high frequency, spread spectrum), integration of GPS with other satellite systems (e.g. Argos, Globalstar) and potential new data recovery technologies (e.g. network nodes). GPS is one component among many rapidly evolving technologies. Therefore, we recommend that users and suppliers interact to ensure the availability of appropriate equipment to meet animal research objectives.
The envelope glycoprotein (Env) complexes of the human and simian immunodeficiency viruses (HIV and SIV, respectively) mediate viral entry and are a target for neutralizing antibodies. The receptor ...binding surfaces of Env are in large part sterically occluded or conformationally masked prior to receptor binding. Knowledge of the unliganded, trimeric Env structure is key for an understanding of viral entry and immune escape, and for the design of vaccines to elicit neutralizing antibodies. We have used cryo-electron tomography and averaging to obtain the structure of the SIV Env complex prior to fusion. Our result reveals novel details of Env organisation, including tight interaction between monomers in the gp41 trimer, associated with a three-lobed, membrane-distal gp120 trimer. A cavity exists at the gp41-gp120 trimer interface. Our model for the spike structure agrees with previously predicted interactions between gp41 monomers, and furthers our understanding of gp120 interactions within an intact spike.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background. Existing severity assessment tools, such as the pneumonia severity index (PSI) and CURB-65 (tool based on confusion, urea level, respiratory rate, blood pressure, and age <65 years), ...predict 30-day mortality in community-acquired pneumonia (CAP) and have limited ability to predict which patients will require intensive respiratory or vasopressor support (IRVS). Methods. The Australian CAP Study (ACAPS) was a prospective study of 882 episodes in which each patient had a detailed assessment of severity features, etiology, and treatment outcomes. Multivariate logistic regression was performed to identify features at initial assessment that were associated with receipt of IRVS. These results were converted into a simple points-based severity tool that was validated in 5 external databases, totaling 7464 patients. Results. In ACAPS, 10.3% of patients received IRVS, and the 30-day mortality rate was 5.7%. The features statistically significantly associated with receipt of IRVS were low systolic blood pressure (2 points), multilobar chest radiography involvement (1 point), low albumin level (1 point), high respiratory rate (1 point), tachycardia (1 point), confusion (1 point), poor oxygenation (2 points), and low arterial pH (2 points): SMART-COP. A SMART-COP score of <3 points identified 92% of patients who received IRVS, including 84% of patients who did not need immediate admission to the intensive care unit. Accuracy was also high in the 5 validation databases. Sensitivities of PSI and CURB-65 for identifying the need for IRVS were 74% and 39%, respectively. Conclusions. SMART-COP is a simple, practical clinical tool for accurately predicting the need for IRVS that is likely to assist clinicians in determining CAP severity.
Mature, infectious HIV‐1 particles contain a characteristic cone‐shaped core that encases the viral RNA and replication proteins. The architectures of mature virions and isolated cores were studied ...using cryo‐electron microscopy. The average size (∼145 nm) of the virion was unchanged during maturation. Most virions contained a single core but roughly one‐third contained two or more cores. Consideration of the capsid protein concentration during core assembly indicated that core formation in vivo is template‐mediated rather than concentration‐driven. Although most cores were conical, 7% were tubular. These displayed a stacked‐disc arrangement with 7‐, 8‐, 9‐ or 10‐fold axial symmetry. Layer line filtration of these images showed that the capsid subunit arrangement is consistent with a 9.6 nm hexamer resembling that previously seen in the helical tubes assembled from purified capsid protein. A common reflection (1/3.2 nm) shared between the tubular and conical cores suggested they share a similar organization. The extraordinary flexibility observed in the assembly of the mature core appears to be well suited to accommodating variation and hence there may be no single structure for the infectious virion.
Point-of-care ultrasound can be used at the bedside to assess the haemodynamic status and fluid responsiveness of a pregnant woman. Previous studies demonstrated that views from the apical and ...parasternal windows are readily obtainable in labouring women. However, using the subcostal window to assess the inferior vena cava can be challenging because of the gravid uterus. A potential alternative is the right upper quadrant transhepatic window. We sought to compare visualisation of the inferior vena cava via the subcostal and right upper quadrant windows, in full-term pregnant women. This was a prospective pilot study carried out in a tertiary academic obstetric centre. Thirty pregnant nonlabouring women at full term were recruited. In each patient, the inferior vena cava was visualised through both the subcostal and the right upper quadrant windows. Time to acquire each image, acquisition success rates and ease of obtaining images were compared for both approaches. Image quality was then reviewed and rated by two independent expert reviewers. There was a significant difference in the time required to obtain each view; subcostal median (interquartile range): 52 (35-59) seconds, right upper quadrant median (interquartile range): 23 (11-55) seconds (P1/40.0045). Operator-defined successful image acquisition was 100% for the right upper quadrant window compared to 80% for the subcostal window. Ease of obtaining the view, as rated by the operator, was significantly easier in the right upper quadrant window compared to the subcostal window (P <0.0001). Both reviewers independently rated image adequacy to be significantly greater in the right upper quadrant window (73% and 57%) compared to the subcostal window (40% and 10%) (P1/40.0213 and P1/40.0005, respectively). Inter-rater agreement ranged between good (Cohen's kappa coefficient 0.64) for right upper quadrant windows to fair (Cohen's kappa coefficient 0.29) for subcostal windows. Inferior vena cava visualisation in term pregnant patients may take less time, be easier and provide better quality images when the right upper quadrant window is used compared to the subcostal window.
Cryopreservation protocols are increasingly required in regenerative medicine applications but must deliver functional products at clinical scale and comply with Good Manufacturing Process (GMP). ...While GMP cryopreservation is achievable on a small scale using a Stirling cryocooler-based controlled rate freezer (CRF) (EF600), successful large-scale GMP cryopreservation is more challenging due to heat transfer issues and control of ice nucleation, both complex events that impact success. We have developed a large-scale cryocooler-based CRF (VIA Freeze) that can process larger volumes and have evaluated it using alginate-encapsulated liver cell (HepG2) spheroids (ELS). It is anticipated that ELS will comprise the cellular component of a bioartificial liver and will be required in volumes of ∼2 L for clinical use. Sample temperatures and Stirling cryocooler power consumption was recorded throughout cooling runs for both small (500 μL) and large (200 mL) volume samples. ELS recoveries were assessed using viability (FDA/PI staining with image analysis), cell number (nuclei count), and function (protein secretion), along with cryoscanning electron microscopy and freeze substitution techniques to identify possible injury mechanisms. Slow cooling profiles were successfully applied to samples in both the EF600 and the VIA Freeze, and a number of cooling and warming profiles were evaluated. An optimized cooling protocol with a nonlinear cooling profile from ice nucleation to -60°C was implemented in both the EF600 and VIA Freeze. In the VIA Freeze the nucleation of ice is detected by the control software, allowing both noninvasive detection of the nucleation event for quality control purposes and the potential to modify the cooling profile following ice nucleation in an active manner. When processing 200 mL of ELS in the VIA Freeze-viabilities at 93.4% ± 7.4%, viable cell numbers at 14.3 ± 1.7 million nuclei/mL alginate, and protein secretion at 10.5 ± 1.7 μg/mL/24 h were obtained which, compared well with control ELS (viability -98.1% ± 0.9%; viable cell numbers -18.3 ± 1.0 million nuclei/mL alginate; and protein secretion -18.7 ± 1.8 μg/mL/24 h). Large volume GMP cryopreservation of ELS is possible with good functional recovery using the VIA Freeze and may also be applied to other regenerative medicine applications.
Background. Available data on the etiology of community-acquired pneumonia (CAP) in Australia are very limited. Local treatment guidelines promote the use of combination therapy with agents such as ...penicillin or amoxycillin combined with either doxycycline or a macrolide. Methods. The Australian CAP Study (ACAPS) was a prospective, multicenter study of 885 episodes of CAP in which all patients underwent detailed assessment for bacterial and viral pathogens (cultures, urinary antigen testing, serological methods, and polymerase chain reaction). Antibiotic agents and relevant clinical outcomes were recorded. Results. The etiology was identified in 404 (45.6%) of 885 episodes, with the most frequent causes being Streptococcus pneumoniae (14%), Mycoplasma pneumoniae (9%), and respiratory viruses (15%; influenza, picornavirus, respiratory syncytial virus, parainfluenza virus, and adenovirus). Antibiotic-resistant pathogens were rare: only 5.4% of patients had an infection for which therapy with penicillin plus doxycycline would potentially fail. Concordance with local antibiotic recommendations was high (82.4%), with the most commonly prescribed regimens being a penicillin plus either doxycycline or a macrolide (55.8%) or ceftriaxone plus either doxycycline or a macrolide (36.8%). The 30-day mortality rate was 5.6% (50 of 885 episodes), and mechanical ventilation or vasopressor support were required in 94 episodes (10.6%). Outcomes were not compromised by receipt of narrower-spectrum β-lactams, and they did not differ on the basis of whether a pathogen was identified. Conclusions. The vast majority of patients with CAP can be treated successfully with narrow-spectrum β-lactam treatment, such as penicillin combined with doxycycline or a macrolide. Greater use of such therapy could potentially reduce the emergence of antibiotic resistance among common bacterial pathogens.
Nude mouse human thymus transplant model: Fresh or cryopreserved and thawed human thymus slices were transplanted subcutaneously into recipient nude mice. Nude mice subsequently produced mouse ...CD3+CD4+ T‐cells.
Cesarean delivery is the most common major surgery worldwide. Noise in healthcare settings leads to impaired communication and concentration, and stress among healthcare providers. Limited ...information is available about noise at cesarean delivery.
This study aimed to achieve a comprehensive analysis of noise that occurs during cesarean deliveries. Sound level meters are used to determine baseline noise levels and to describe the frequency of acute noise generated during a cesarean delivery that will cause a human startle response. Secondarily, we aimed to evaluate the effectiveness of a visual alarm system in mitigating excessive noise.
We completed a preintervention/postintervention observational study of noise levels during cesarean deliveries before and after introduction of a visual alarm system for noise mitigation between February 15, 2021 and August 26, 2021. There were 156 cases included from each study period. Sound pressure levels were analyzed by overall case median decibel levels and by time epoch for relevant phases of the operation. Rapid increases in noise events capable of causing a human startle response, “startle events,” were detected by retrospective analysis, with quantification for baselines and analysis of frequency by case type. Median noise levels with interquartile ranges are presented. Data are compared between epochs and case characteristics with nonparametric 2-tailed testing.
The median acoustic pressure for all cesarean deliveries was 61.8 (58.8–65.9) (median interquartile range) dBA (A-weighted decibels). The median dBA for the full case time period was significantly higher in cases with neonatal intensive care unit team presence (62.1 60.5–63.9), admission to the neonatal intensive care unit (62.0 60.4–63.9), 5-minute Apgar score <7 (62.2 61.1–64.3), multiple gestations (62.6 62.0–64.2), and intraoperative tubal sterilization (62.8 61.5–65.1). The use of visual alarms was associated with a statistically significant reduction of median noise level by 0.7 dBA, from 61.8 (60.6–63.5) to 61.1 (59.8–63.7) dBA (P<.001).
The noise intensities recorded during cesarean deliveries were commonly at levels that affect communication and concentration, and above the safe levels recommended by the World Health Organization. Although noise was reduced by 0.7 dBA, the reduction was not clinically significant in reaching a discernible amount (a 3-dB change) or in reducing “startle events.” Isolated use of visual alarms during cesarean deliveries is unlikely to be a satisfactory noise mitigation strategy.
The process of ice formation and propagation during cryopreservation impacts on the post-thaw outcome for a sample. Two processes, either network solidification or progressive solidification, can ...dominate the water–ice phase transition with network solidification typically present in small sample cryo-straws or cryo-vials. Progressive solidification is more often observed in larger volumes or environmental freezing. These different ice phase progressions could have a significant impact on cryopreservation in scale-up and larger volume cryo-banking protocols necessitating their study when considering cell therapy applications.
This study determines the impact of these different processes on alginate encapsulated liver spheroids (ELS) as a model system during cryopreservation, and develops a method to replicate these differences in an economical manner.
It was found in the current studies that progressive solidification resulted in fewer, but proportionally more viable cells 24h post-thaw compared with network solidification. The differences between the groups diminished at later time points post-thaw as cells recovered the ability to undertake cell division, with no statistically significant differences seen by either 48h or 72h in recovery cultures.
Thus progressive solidification itself should not prove a significant hurdle in the search for successful cryopreservation in large volumes. However, some small but significant differences were noted in total viable cell recoveries and functional assessments between samples cooled with either progressive or network solidification, and these require further investigation.
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