Risk of tendon failure with repeated passage of Kirschner wires or hypodermic needles: an experimental study

During hand surgery, tendons may be at risk of damage. This biomechanical study aims to assess the risk of tendon rupture due to passage of Kirschner wires or hypodermic needles. Porcine extensor tendons were divided into four groups. Group 1: a control group was tested to ensure that repeated stress alone did not cause failure. Group 2a: 1.1-mm Kirschner wires were hand pushed through tendons 50 times and then stressed to 40 N, repeated until tendon failure. In Group 2b, K-wires were passed while rotating using a drill. Group 3: the experiment was repeated using a 20 G hypodermic needle. Group 2a tendons required a median of 2450 passes (1150–3500) to propagate failure, Group 2b a median of 2250 (1200–3850) and Group 3a median of 200 passes (150–450). The risk of tendon rupture from wires or hypodermic needles in procedures appears very low.

Newcastle disease vaccine virus I-2 fails to acquire virulence during repeated passage in vivo

Background This study determined whether the naturally attenuated, thermotolerant Newcastle disease vaccine virus I-2 could acquire virulence after five in vivo passages through SPF chickens. Methods Study design was to international requirements including European Pharmacopoeia, Ph. Eur., v9.0 04/2013:0450, 2013. I-2 Working Seed (WS) was compared with five-times-passaged I-2 WS (5XP WS) in intracerebral pathogenicity index (ICPI), Fo cleavage site sequencing and Safety tests. Results The first passage series used a 50% brain: 50% tracheal tissue challenge homogenate and was unsuccessful as I-2 was not detected after the fourth passage. A second passage series used 10% brain: 90% tracheal tissue homogenates. I-2 was isolated from tracheal tissue in each passage. However harvested titres were below the minimum challenge level (107 EID50) specified for the ICPI and Safety tests, possibly reflecting I-2’s inherently low pathogenicity (interestingly caecal tonsils yielded significant titres). Given this the WS and 5XP WS comparisons proceeded. ICPI values were 0.104 and 0.073 for the WS group and the 5XP WS group respectively confirming that I-2, whether passaged or not, expressed low pathogenicity. F0 amino-acid sequences for both WS and 5XP WS were identified as 112R-K-Q-G-R-↓-L-I-G119 and so compatible with those of avirulent ND viruses. In safety, no abnormal clinical signs were observed in both groups except for two chicks in the 5XP WS group, where one bird was withdrawn due to a vent prolapse, and another bird died with inconclusive necropsy results. Conclusions: These data, the issue of low passage titres with little or no virus isolation from brain tissues and the genomic copy approach suggest a need to amend Ph. Eur. v9.0 04/2013:0450, 2013 for naturally attenuated, low pathogenicity vaccine viruses such as I-2. From an international regulatory perspective, the study provides further definitive data demonstrating that Newcastle disease vaccine virus I-2 is safe for use.

Efficacy of attenuated bacteria vaccine against streptococcal infection in larvae tilapia (Oreochromis niloticus)

One of the common diseases found in tilapia is a streptococcal disease caused by the Streptococcus agalactiae bacteria. Treatment of this disease is generally done by using antibiotics. The use of antibiotics in controlling disease in fish can create resistant bacterial strains with certain doses. The use of vaccines is one of the alternative control methods in fish defence against infections. The purpose of this study was to analyze the efficacy of vaccination on seeds through immersion using attenuated active bacteria to increase immunity at the beginning of the spread of streptococcosis disease. The vaccine used was obtained from attenuated Streptococcus agalactiae bacteria through repeated passage ten times. Vaccination was carried out through oral vaccine. Challenge tests were carried out on days 7, 14, and 21 days after vaccination on tilapia larvae by immersion. The result indicated that vaccination using attenuated bacteria could increase lysozyme activity at each observation time compared to control. The mortality of post-challenged larvae on days 7, 14 and 21 post-vaccination was lower than that of unvaccinated seed. The percentage of RPS values up to the 14th day of observation has increased and tends to decrease on the 21st day.

Newcastle disease vaccine virus I-2 fails to acquire virulence during repeated passage in vivo

Background This study determined whether the naturally attenuated, thermotolerant Newcastle disease vaccine virus I-2 could acquire virulence after five in vivo passages through SPF chickens. Methods Study design was to international requirements including European Pharmacopoeia, Ph. Eur., v9.0 04/2013:0450, 2013. I-2 Working Seed (WS) was compared with five-times-passaged I-2 WS (5XP WS) in intracerebral pathogenicity index (ICPI), Fo cleavage site sequencing and Safety tests. Results The first passage series used a 50% brain: 50% tracheal tissue challenge homogenate and was unsuccessful as I-2 was not detected after the fourth passage. A second passage series used 10% brain: 90% tracheal tissue homogenates. I-2 was isolated from tracheal tissue in each passage. However harvested titres were below the minimum challenge level (107 EID50) specified for the ICPI and Safety tests, possibly reflecting I-2’s inherently low pathogenicity (interestingly caecal tonsils yielded significant titres). Given this the WS and 5XP WS comparisons proceeded. ICPI values were 0.104 and 0.073 for the WS group and the 5XP WS group respectively confirming that I-2, whether passaged or not, expressed low pathogenicity. F0 amino-acid sequences for both WS and 5XP WS were identified as 112R-K-Q-G-R-↓-L-I-G119 and so compatible with those of avirulent ND viruses. In safety, no abnormal clinical signs were observed in both groups except for two chicks in the 5XP WS group, where one bird was withdrawn due to a vent prolapse, and another bird died with inconclusive necropsy results. Conclusions: These data, the issue of low passage titres with little or no virus isolation from brain tissues and the genomic copy approach suggest a need to amend Ph. Eur. v9.0 04/2013:0450, 2013 for naturally attenuated, low pathogenicity vaccine viruses such as I-2. From an international regulatory perspective, the study provides further definitive data demonstrating that Newcastle disease vaccine virus I-2 is safe for use.

Newcastle disease vaccine virus I-2 fails to acquire virulence during repeated passage in vivo

Background This study determined whether the naturally attenuated, thermotolerant Newcastle disease vaccine virus I-2 could acquire virulence after five in vivo passages through SPF chickens. Methods Study design was to international requirements including European Pharmacopoeia, Ph. Eur., v9.0 04/2013:0450, 2013. I-2 Working Seed (WS) was compared with five-times-passaged I-2 WS (5XP WS) in intracerebral pathogenicity index (ICPI), Fo cleavage site sequencing and Safety tests. Results The first passage series used a 50% brain: 50% tracheal tissue challenge homogenate and was unsuccessful as I-2 was not detected after the fourth passage. A second passage series used 10% brain: 90% tracheal tissue homogenates. I-2 was isolated from tracheal tissue in each passage. However harvested titres were below the minimum challenge level (107 EID50) specified for the ICPI and Safety tests, possibly reflecting I-2’s inherently low pathogenicity (interestingly caecal tonsils yielded significant titres). Given this the WS and 5XP WS comparisons proceeded. ICPI values were 0.104 and 0.073 for the WS group and the 5XP WS group respectively confirming that I-2, whether passaged or not, expressed low pathogenicity. F0 amino-acid sequences for both WS and 5XP WS were identified as 112R-K-Q-G-R-↓-L-I-G119 and so compatible with those of avirulent ND viruses. In safety, no abnormal clinical signs were observed in both groups except for two chicks in the 5XP WS group, where one bird was withdrawn due to a vent prolapse, and another bird died with inconclusive necropsy results. Conclusions: These data, the issue of low passage titres with little or no virus isolation from brain tissues and the genomic copy approach suggest a need to amend Ph. Eur. v9.0 04/2013:0450, 2013 for naturally attenuated, low pathogenicity vaccine viruses such as I-2. These results add to the literature and field data demonstrating that Newcastle Disease vaccine virus I-2 is safe for use.

Influence of Composite Polymer Coatings on the Insertion Force of Needle-Like Structure in Soft Materials

This study is aimed to evaluate the effects of coated surgical needles with composite polymers such as polydopamine (PDA), polytetrafluoroethylene (PTFE), and carbon. The coated needle’s lubrication properties were measured using 3 DOF force sensors and 3D robot system by the repetitive insertion in soft tissue materials. Needle durability is a measure of needle sharpness after repeated passage through high stiffness tissue materials. The composite coatings were shown to reduce the insertion force by ∼49% and retraction forces by ∼46% when tested using a bovine kidney. The surface roughness and the lateral friction force of the needle are measured using the Atomic Force Microscope (AFM). The adhesion energy of the different coating on the needle will be measured using a nano-scratch method.

Aligning nuclear cluster orbits with an active galactic nucleus accretion disc

ABSTRACT Active galactic nuclei (AGN) are powered by the accretion of discs of gas on to supermassive black holes (SMBHs). Stars and stellar remnants orbiting the SMBH in the nuclear star cluster (NSC) will interact with the AGN disc. Orbiters plunging through the disc experience a drag force and, through repeated passage, can have their orbits captured by the disc. A population of embedded objects in AGN discs may be a significant source of binary black hole mergers, supernovae, tidal disruption events, and embedded gamma-ray bursts. For two representative AGN disc models, we use geometric drag and Bondi–Hoyle–Littleton drag to determine the time to capture for stars and stellar remnants. We assume a range of initial inclination angles and semimajor axes for circular Keplerian prograde orbiters. Capture time strongly depends on the density and aspect ratio of the chosen disc model, the relative velocity of the stellar object with respect to the disc, and the AGN lifetime. We expect that for an AGN disc density $\rho \gtrsim 10^{-11}{\rm g\, cm^{-3}}$ and disc lifetime ≥1 Myr, there is a significant population of embedded stellar objects, which can fuel mergers detectable in gravitational waves with LIGO-Virgo and LISA.

EPIZOOTIC ANALYSIS OF FACTOR-INFECTED CATTLE FARMS

The article presents data on biocenotic diagnostics of 12 farms in the Moscow region that are endowed with endometritis and mastitis in cows, as well as gastrointestinal and respiratory diseases of newborn calves, with the aim of identifying zoo-hygienic, zootechnical and veterinary deficiencies to optimize the strategy for dealing with them. Studies on biocenoses were carried out in 12 farms unsuccessful in cows’ obstetric and gynecological diseases, gastrointestinal and respiratory diseases of newborn calves, with a total number of cattle 12 254, including 4445 cows. For this purpose, field trips were periodically carried out for epizootological examinations of farm biogeocenoses and for the selection of blood serum stabilized with heparin and samples of pathological material for bacteriological, mycological, virological, hematological and immunological studies. It was established that in experimental farms there are no proper conditions to ensure the breaking of the epizootic chain during the infectious process. So, the main factors that contribute to the development and spread of these pathologies are poor food supply, violations of elementary veterinary and sanitary rules for keeping and milking, and failure to fully implement measures to prevent these diseases. An analysis of the epizootic situation for cattle diseases caused by conditionally pathogenic bacteria indicates that farms that are unsuccessful for factor infections have all the conditions for the circulation of pathogens, repeated passage through susceptible animals, the increase in the virulence of conditionally pathogenic microorganisms, and in some cases for appearing pathogenicity in saprophytic bacteria. An effective fight against malignant microbial ecosystems requires in-depth knowledge of the parasitocenoses’ quantitative and species composition, the study of relationships between its individual representatives, the mandatory identification of pure cultures of all its members, and determination of the microbial agents marker biological properties, as well as detailed biocenotic diagnosis of the animal habitat (farm, barn, etc.).

On-Site–Modified Sheath to Overcome the Undesirable Catheterization of the Profunda Femoris Artery During Antegrade Femoral Access

Purpose: To present a simple method to avoid favored passage of a guidewire into the profunda femoris artery (PFA) after antegrade puncture of the common femoral artery. Technique: A 6-F conventional introducer sheath with a radiopaque distal marker is placed on the nurse’s table with its side port orientated to the 12 o’clock position. A small (2–2.5 mm) oval fenestration is created on the superior aspect of the sheath about 3 cm from its tip with a size 11 surgical blade. The modified introducer is passed over the angled 0.035-inch guidewire into the PFA and gently retrieved until the tip marker is ~3 cm from the femoral bifurcation. The dilator is removed, and the guidewire is withdrawn to the level of the fenestration, manipulated through it, and advanced further into the superficial femoral artery under fluoroscopic guidance. Conclusion: When repeated passage of the guidewire down the PFA persists despite conventional manipulation of the wire or needle, an on-site modification of the sheath is an easy alternative approach for the catheterization of the superficial femoral artery.