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61.
62.
Swine spermatozoa were encapsulated in barium alginate and protamine-barium alginate membranes to lengthen their preservation time and to provide a means of controlling their release. Precocious acrosome reactions and secondary anomalies were measured as indices of semen quality. These characteristics were observed for two forms of encapsulated spermatozoa when stored at 18 and 38 degrees C for 24 h and for semen diluted in a classical extender at both temperatures. The results indicate that encapsulation enhances semen preservation, providing protection against membrane damage upon dilution. The effect is even more evident at the higher temperature (38 degrees C), where cell metabolism is higher. An in vitro release test of spermatozoa showed a massive cell delivery from barium alginate capsules within 6 h, and a slow release from protamine-barium alginate capsules. The properties of spermatozoa 24 h after release did not differ from the semen stored at the same temperature in capsules, indicating that the release process does not impair semen quality.  相似文献   
63.
Human hair follicle cells, both bulge and dermal papilla cells, were isolated and cultured in a GMP cell factory, in order to obtain an in vitro hair follicle source for encapsulation end transplantation in alopecia regenerative cell therapy. An in vitro model, constituted by organotypic cultures of human skin sample, was set up to simulate the dermal-epidermal interaction between bulge cells and dermal papilla cells, evaluating the possible new follicles formation and the regenerative potentiality of these hair follicle cells. Both the bulge and dermal papilla cells show an excellent cellular proliferation as well as an abundant extracellular matrix production. The immunofluorescence investigation revealed the positivity of both cell lines to CK15 and CD200, whereas both cell lines were negative to CD71 and Oct-4. The pool of cultured bulge and dermal papilla cells was injected into the deep dermis; at day 28 of culture, some organized areas with a higher cell density can be observed: the cells self-organize into papilla-like lengthened aggregates. In samples in which the follicular cells have been seeded on the dermis surface, an epidermis-like homogeneous monolayer on the dermis surface can be seen, therefore showing a potentiality of these cells for epidermis regeneration. These data show the efficacy of a cellular isolation and amplification approach to obtain an in vitro human hair follicle regenerative source on industrial scale in a GMP cell factory. The results also proved an intrinsic potentiality of follicular cells to in vitro recreate the epidermis for tissue engineering purposes. Thus, it is feasible to produce bioengineered hair follicles in a GMP cell factory, for encapsulation and transplantation in alopecic patients.  相似文献   
64.
Detecting antibody responses during and after SARS‐CoV‐2 infection is essential in determining the seroepidemiology of the virus and the potential role of antibody in disease. Scalable, sensitive and specific serological assays are essential to this process. The detection of antibody in hospitalized patients with severe disease has proven relatively straightforward; detecting responses in subjects with mild disease and asymptomatic infections has proven less reliable. We hypothesized that the suboptimal sensitivity of antibody assays and the compartmentalization of the antibody response may contribute to this effect. We systematically developed an ELISA, optimizing different antigens and amplification steps, in serum and saliva from non‐hospitalized SARS‐CoV‐2‐infected subjects. Using trimeric spike glycoprotein, rather than nucleocapsid, enabled detection of responses in individuals with low antibody responses. IgG1 and IgG3 predominate to both antigens, but more anti‐spike IgG1 than IgG3 was detectable. All antigens were effective for detecting responses in hospitalized patients. Anti‐spike IgG, IgA and IgM antibody responses were readily detectable in saliva from a minority of RT‐PCR confirmed, non‐hospitalized symptomatic individuals, and these were mostly subjects who had the highest levels of anti‐spike serum antibodies. Therefore, detecting antibody responses in both saliva and serum can contribute to determining virus exposure and understanding immune responses after SARS‐CoV‐2 infection.  相似文献   
65.
The aim of the present study was to highlight the effect of two different techniques of one embryo crushing on some hormonal changes. Ten twinning mares were submitted to the mobile or fixed manual crushing of one blastocyst within day 19 after the last mating. Blood sample was collected from 20 min before to 90 min, 24 and 72 h after the procedure was performed to analyse 15‐ketodihydro‐PGF2α, cortisol and progesterone plasma concentrations. Singleton pregnancy diagnosis was checked 72 h after crushing and at term of pregnancy. Because the unwanted crushing of both embryos occurred in one mare during the attempt of manual separation of the twins, that mare was not included in the evaluation of crushing‐induced hormonal changes. No significant differences in hormonal concentrations were observed after one embryo crushing and also when the effect of the mobile (n = 6) or fixed (n = 3) technique was specifically evaluated. When the effect of the two techniques on each post‐crushing sampling time hormonal levels was analysed, only a higher cortisol level 30 min after the fixed compared with the mobile technique was observed. The crushing performed within 19 days of gestation does not induce significant changes in 15‐ketodihydro‐PGF2α, cortisol or progesterone plasma concentrations. When the fixed technique was performed, only a temporary higher cortisol concentration was seen 30 min after crushing, suggesting that the fixed technique might be responsible for a slight level of stress for the mare.  相似文献   
66.
OBJECTIVES: To evaluate short term immunological changes after agricultural exposure to commercial formulations of chlorophenoxy herbicides. METHODS: Blood samples were collected from 10 farmers within seven days before exposure, one to 12 days after exposure, and again 50 to 70 days after exposure. Whole blood was used to count lymphocyte subsets with monoclonal antibodies. Peripheral blood mononuclear (PBM) cells were used to measure natural killer (NK) cell activity and lymphocyte response to mitogenic stimulations. Values before exposure were used as reference. RESULTS: In comparison with concentrations before exposure, a significant reduction was found one to 12 days after exposure in the following variables (P < 0.05): circulating helper (CD4) and suppressor T cells (CD8), CD8 dim, cytotoxic T lymphocytes (CTL), natural killer cells (NK), and CD8 cells expressing the surface antigens HLA-DR (CD8-DR), and lymphoproliferative response to mitogen stimulations. All immunological values found 50-70 days after exposure were comparable with concentrations before exposure, but mitogenic proliferative responses of lymphocytes were still significantly decreased. CONCLUSIONS: According to our data agricultural exposure to commercial 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA) formulations may exert short term immunosuppressive effects. Further studies should clarify whether the immunological changes found may have health implications and can specifically contribute to cancer aetiology.  相似文献   
67.
The degenerative pathologies of the intervertebral disc have a remarkable social impact in the industrialized countries and can provide serious disabilities in the population. The current treatment consists of conservative treatments (such as symptomatic pharmacological therapies and physiokinetic therapy) and surgical treatments (intervertebral fusion, total disc replacement, nucleus pulposus (NP) replacement, or surgical exeresis). Recent advances in cell therapy foresee the possibility of regenerating the damaged disc; the autologous disc tissue can be withdrawn, in vitro regenerated, and re-implanted. The aim of this work was to verify whether autologous adipose-derived adult stem cells can improve the quality of an in vitro reconstructed nucleus pulposus tissue. A three-dimensional (3D) co-culture of NP cells and adipose tissue non-adipocyte fraction cells (nAFs) was assessed in a previously developed alginate 3D culture system following the good manufacturing practice guidelines to ensure patient safety for clinical studies. Morphological investigation of cultured and co-cultured cells was performed using transmission electron microscopy and immunofluorescence for collagen type I, aggrecan, CD90, CD34, and vimentin. Results indicate that co-culture of NP and nAFs improves the quality of the in vitro reconstructed tissue in term of extracellular matrix production and 3D cell organization. Technological resources are available for NP cell encapsulation intended for regenerating the intervertebral disc.  相似文献   
68.
69.
Dried blood spot (DBS) samples can be used for the detection of severe acute respiratory syndrome coronavirus 2 spike antibodies. DBS sampling is comparable to matched serum samples with a relative 98.1% sensitivity and 100% specificity. Thus, DBS sampling offers an alternative for population-wide serologic testing in the coronavirus pandemic.  相似文献   
70.

Purpose

The ductus venosus (DV) blood flow has been studied in fetal lambs and in humans. This study aims to describe the velocities, the Doppler indices and the morphological patterns of the venous blood flow in the DV of canine fetuses during physiological pregnancy.

Methods

The DV of 55 canine fetuses has been evaluated and the waveforms described using B-mode, color and pulsed-wave Doppler ultrasound technology.

Results

We found 48 diphasic waves and 7 threephasic waves. No monophasic waveform was found. Six of seven threephasic waveforms belonged to litters in which perinatal mortality occurred. The peak velocity during ventricular systole S (cm/s), the peak velocity during the ventricular diastole D (cm/s), the velocity during atrial contraction aV (cm/s), the S/D index, the pulsatility index (PI) and the resistance index were measured.

Conclusions

All Doppler indices and velocities were significantly correlated with each other (p < 0.05). The number of newborn puppies and the age of bitches were not related to DV vascular indices or flow rate (p > 0.05). Gestational age was proportional to the PI (p < 0.02). Doppler ultrasonography allows the assessment of DV blood flow in canine fetuses during pregnancy.  相似文献   
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