Unraveling Pre-filled Syringe Needle Clogging: Exploring a Fresh Outlook Through Innovative Techniques.

OBJECTIVE: This study aimed to investigate the movement of liquid in the needle region of staked-in-needle pre-filled syringes using neutron imaging and synchrotron X-ray tomography. The objective was to gain insights into the dynamics of liquid presence and understand the factors contributing to needle clogging. METHODS: Staked-in-needle pre-filled syringes were examined using neutron radiography and synchrotron X-ray phase-contrast computed tomography. Neutron radiography provided a 2D visualization of liquid presence in the needle, while synchrotron X-ray tomography offered high-resolution 3D imaging to study detailed morphological features of the liquid. RESULTS: Neutron radiography revealed liquid presence in the needle region for as-received samples and after temperature and pressure cycling. Pressure cycling had a more pronounced effect on liquid formation. Synchrotron X-ray tomography confirmed the presence of liquid and revealed various morphologies, including droplets of different sizes, liquid segments blocking sections of the needle, and a thin layer covering the needle wall. Liquid presence was also observed between the steel needle and the glass barrel. CONCLUSIONS: The combination of neutron imaging and synchrotron X-ray tomography provided valuable insights into the dynamics of liquid movement in staked-in-needle pre-filled syringes. Temperature and pressure cycling were found to contribute to additional liquid formation, with pressure changes playing a significant role. The detailed morphological analysis enhanced the understanding of microstructural arrangements within the needle. This research contributes to addressing the issue of needle clogging and can guide the development of strategies to improve pre-filled syringe performance.

Micro- and nanostructure specific X-ray tomography reveals less matrix formation and altered collagen organization following reduced loading during Achilles tendon healing.

Recovery of the collagen structure following Achilles tendon rupture is poor, resulting in a high risk for re-ruptures. The loading environment during healing affects the mechanical properties of the tendon, but the relation between loading regime and healing outcome remains unclear. This is partially due to our limited understanding regarding the effects of loading on the micro- and nanostructure of the healing tissue. We addressed this through a combination of synchrotron phase-contrast X-ray microtomography and small-angle X-ray scattering tensor tomography (SASTT) to visualize the 3D organization of microscale fibers and nanoscale fibrils, respectively. The effect of in vivo loading on these structures was characterized in early healing of rat Achilles tendons by comparing full activity with immobilization. Unloading resulted in structural changes that can explain the reported impaired mechanical performance. In particular, unloading led to slower tissue regeneration and maturation, with less and more disorganized collagen, as well as an increased presence of adipose tissue. This study provides the first application of SASTT on soft musculoskeletal tissues and clearly demonstrates its potential to investigate a variety of other collagenous tissues. STATEMENT OF SIGNIFICANCE: Currently our understanding of the mechanobiological effects on the recovery of the structural hierarchical organization of injured Achilles tendons is limited. We provide insight into how loading affects the healing process by using a cutting-edge approach to for the first time characterize the 3D micro- and nanostructure of the regenerating collagen. We uncovered that, during early healing, unloading results in a delayed and more disorganized regeneration of both fibers (microscale) and fibrils (nanoscale), as well as increased presence of adipose tissue. The results set the ground for the development of further specialized protocols for tendon recovery.

Multimodal and multiscale characterization reveals how tendon structure and mechanical response are altered by reduced loading.

Tendons are collagen-based connective tissues where the composition, structure and mechanics respond and adapt to the local mechanical environment. Adaptation to prolonged inactivity can result in stiffer tendons that are more prone to injury. However, the complex relation between reduced loading, structure, and mechanical performance is still not fully understood. This study combines mechanical testing with high-resolution synchrotron X-ray imaging, scattering techniques and histology to elucidate how reduced loading affects the structural properties and mechanical response of rat Achilles tendons on multiple length scales. The results show that reduced in vivo loading leads to more crimped and less organized fibers and this structural inhomogeneity could be the reason for the altered mechanical response. Unloading also seems to change the fibril response, possibly by altering the strain partitioning between hierarchical levels, and to reduce cell density. This study elucidates the relation between in vivo loading, the Achilles tendon nano-, meso­structure and mechanical response. The results provide fundamental insights into the mechanoregulatory mechanisms guiding the intricate biomechanics, tissue structural organization, and performance of complex collagen-based tissues. STATEMENT OF SIGNIFICANCE: Achilles tendon properties allow a dynamic interaction between muscles and tendon and influence force transmission during locomotion. Lack of physiological loading can have dramatic effects on tendon structure and mechanical properties. We have combined the use of cutting-edge high-resolution synchrotron techniques with mechanical testing to show how reduced loading affects the tendon on multiple hierarchical levels (from nanoscale up to whole organ) clarifying the relation between structural changes and mechanical performance. Our findings set the first step to address a significant healthcare challenge, such as the design of tailored rehabilitations that take into consideration structural changes after tendon immobilization.

A new possibility of sex determination in alleculine specimens (Coleoptera: Tenebrionidae: Alleculinae) of the Palaearctic and the Oriental genera.

Differences between numbers of teeth in protarsal claws of males and those of females were determined for 85 genera of Alleculinae Laporte, 1840 from the Oriental and the Palaearctic regions which are inhabited by a total of 114 genera. Males of more than 72 % of the genera studied possess more numerous teeth on protarsal claws compared to females. This character makes it possible to differentiate males from females without dissecting the genitalia.

Heterotopic mineral deposits in intact rat Achilles tendons are characterized by a unique fiber-like structure.

Heterotopic mineralization entails pathological mineral formation inside soft tissues. In human tendons mineralization is often associated with tendinopathies, tendon weakness and pain. In Achilles tendons, mineralization is considered to occur through heterotopic ossification (HO) primarily in response to tendon pathologies. However, refined details regarding HO deposition and microstructure are unknown. In this study, we characterize HO in intact rat Achilles tendons through high-resolution phase contrast enhanced synchrotron X-ray tomography. Furthermore, we test the potential of studying local tissue injury by needling intact Achilles tendons and the relation between tissue microdamage and HO. The results show that HO occurs in all intact Achilles tendons at 16 weeks of age. HO deposits are characterized by an elongated ellipsoidal shape and by a fiber-like internal structure which suggests that some collagen fibers have mineralized. The data indicates that deposition along fibers initiates in the pericellular area, and propagates into the intercellular area. Within HO deposits cells are larger and more rounded compared to tenocytes between unmineralized fibers, which are fewer and elongated. The results also indicate that multiple HO deposits may merge into bigger structures with time by accession along unmineralized fibers. Furthermore, the presence of unmineralized regions within the deposits may indicate that HOs are not only growing, but mineral resorption may also occur. Additionally, phase contrast synchrotron X-ray tomography allowed to distinguish microdamage at the fiber level in response to needling. The needle injury protocol could in the future enable to elucidate the relation between local inflammation, microdamage, and HO deposition.

Fracture behavior of a composite of bone and calcium sulfate/hydroxyapatite.

Calcium sulfate/hydroxyapatite (CaS/HA) biomaterials have been investigated for use in several orthopedic applications. However, the mechanical interactions between the composite of CaS/HA and bone at the microscale are still unknown. The aim of this study was to determine if and how augmentation with CaS/HA alters the fracture behavior of bone. Eleven cylinders of trabecular bone were drilled from human femoral heads and cleaned from bone marrow. Among them, five cylinders were injected with CaS/HA to generate composite specimens, while the others were kept intact. One extra specimen of pure CaS/HA was prepared. All specimens were compressed in situ using synchrotron X-ray tomography and imaged at ∼2% strain intervals. Structural properties were calculated from the images in unloaded state and mechanical properties were determined from the load-curves. CaS/HA alone displayed the highest peak force and stiffness and the lowest strain at fracture. All composite specimens had a higher peak force than the pure bone specimens and the composite specimens had higher toughness than the pure CaS/HA specimen. Furthermore, the fracture behavior was analyzed further to characterize the local deformations. The pure bone specimens presented damage in multiple trabeculae and the CaS/HA specimen displayed sharp transition in strains, with low strain in one load step and large cracks in the next. The composite specimens deformed uniformly, with the CaS/HA preventing tissue damage and the bone preventing cracks in the CaS/HA from propagating through the specimen. In conclusion, using tomography with in situ loading, it was possible to show how CaS/HA can help prevent bone tissue damage before global failure.

A quality optimization approach to image Achilles tendon microstructure by phase-contrast enhanced synchrotron micro-tomography.

Achilles tendons are mechanosensitive, and their complex hierarchical structure is in part the result of the mechanical stimulation conveyed by the muscles. To fully understand how their microstructure responds to mechanical loading a non-invasive approach for 3D high resolution imaging suitable for soft tissue is required. Here we propose a protocol that can capture the complex 3D organization of the Achilles tendon microstructure, using phase-contrast enhanced synchrotron micro-tomography (SR-PhC-µCT). We investigate the effects that sample preparation and imaging conditions have on the resulting image quality, by considering four types of sample preparations and two imaging setups (sub-micrometric and micrometric final pixel sizes). The image quality is assessed using four quantitative parameters. The results show that for studying tendon collagen fibers, conventional invasive sample preparations such as fixation and embedding are not necessary or advantageous. Instead, fresh frozen samples result in high-quality images that capture the complex 3D organization of tendon fibers in conditions as close as possible to natural. The comprehensive nature of this innovative study by SR-PhC-µCT breaks ground for future studies of soft complex biological tissue in 3D with high resolution in close to natural conditions, which could be further used for in situ characterization of how soft tissue responds to mechanical stimuli on a microscopic level.

New genera of Alleculinae (Coleoptera: Tenebrionidae: Alleculinae: Alleculini) from the Oriental Region. Part XI-Vietnalia gen. nov.

A new genus of Alleculinae (tribe Alleculini Laporte, 1840, subtribe Alleculina Laporte, 1840), Vietnalia gen. nov. with the species Vietnalia catcatica sp. nov. as a type species from the Oriental Region (Vietnam, Lao Cai Province), is described, illustrated and compared with similar (shape of body) genera Doranalia Novák, 2020 and Nikomenalia Dubrovina, 1975. Vietnalia catcatica gen. nov. and sp. nov. distinctly differs from Doranalia and Nikomenalia species particularly by antennomere 3 approximately as long as antennomere 4 in males and slightly longer than antennomere 4 in females, by ultimate maxillary palpomere widely triangular, transverse, strongly widened apically, female has antenna shorter than half body length, male abdomen has 6 visible ventrites, male ultimate and penultimate abdominal ventrites have impressions, male ultimate abdominal ventrite is excised in middle of apex. Male space between eyes is distinctly wider than in males of Doranalia species.

A new species of Cornucistela Campbell, 1980 (Coleoptera: Tenebrionidae: Alleculinae: Gonoderina) from Iran.

A second species of the previously monotypic genus Cornucistela (C. anichtchenkoi sp. nov.) is described, illustrated and compared with C. serrata Campbell, 1980 (type species). It is a first record of the genus in Iran (South Khorasan Province).

A checklist of comb-clawed beetles (Coleoptera: Tenebrionidae: Alleculinae) from Iran.

The fauna of Iranian Alleculinae is summarized in this paper. Seventy species from 12 genera are reported: the subtribe Alleculina Laporte with 4 genera and 18 species: Hymenalia Mulsant (7 species), Hymenophorus Mulsant (3 species), Mycetocharina Seidlitz (6 species), Prionychus Solier (2 species); the subtribe Gonoderina Seidlitz with 3 genera and 6 species: Gonodera Mulsant (1 species), Isomira Mulsant (4 species), Pseudocistela Crotch (1 species), the subtribe Mycetocharina Gistel with a single genus and 3 species: Mycetochara Berthold (3 species) and the tribe Cteniopodini Solier with 4 genera and 43 species: Cteniopus Solier (5 species), Omophlina Reitter (2 species), Omophlus Dejean (32 species) and Podonta Solier (4 species). Nine species are newly recorded for the fauna of Iran: Hymenalia atronitens (Fairmaire, 1892), Mycetocharina rufotestacea Reitter, 1898, Prionychus asiatica (Fairmaire, 1892), Isomira nitidula (Kiesenwetter, 1861), Mycetochara ocularis Reitter, 1884, Cteniopus impressicolis Fairmaire, 1892, Omophlus afghanus Muche, 1965, Omophlus schmidi Muche, 1965 and Podonta elongata Ménétriés, 1832.

Lifestyle decreases risk factors for cardiovascular diseases.

The morbidity and mortality of cardiovascular diseases is high in the developed countries. The lifestyle changes are capable to decrease it by 50%. The aim of the present study was to measure the parameters of some risk factors before and after a one-week NEW START rehabilitative retreat. 1349 volunteers, 320 men, 1029 woman, mean age 51 +/- 14.5 (SD) years participated in 30 rehabilitative retreats from 1999-2006 in the Czech Republic, using a low-fat, low-energy, lacto-ovo-vegetarian diet and exercise, in a stress-free environment. Body weight, height, BMI, blood pressure, heart rate, serum cholesterol and blood glucose were measured. Body weight decreased in 1223 measured persons from 71.2 +/- 14.38 (SD) to 70.6 +/- 14.02 kg (p<0.0001), BMI (1,046 measured persons) from 25.1 +/- 4.60 (SD) to 24.8+4.49 (SD) kg/m2 (p<0.0001), systolic blood pressure (1,218 persons) from 129.8 +/- 23.02 (SD) to 123.8 +/- 21.52 (SD) mmHg (p<0.0001), diastolic blood pressure (1210 persons) from 79.8 +/- 12.7 (SD) to 77.5 +/- 11.6 (SD) mmHg (p<0.0001), serum cholesterol (998 persons) from 4.86 +/- 0.95 (SD) to 4.32 +/- 0.77 (SD) mmol (p<0.0001), blood glucose (544 persons) from 4.31 +/- 1.59 (SD) to 3.88 +/- 1.33 (SD) mmol (p<0.0001). Heart rate was not significantly decreased. The parameters were lower in lacto-ovo vegetarians and Seventh-day Adventists than in controls who never observed the diet and avail the lifestyle programs. The parameters were nonsignificantly changed one year after finishing the retreat in the sample of 68 persons showing the positive effect of retreats. Our results showed, that the intake of a low-fat, low-energy diet, over the course of one week in a stress-free environment, had positive impact on the risk factors of cardiovascular diseases.