In vitro comparative study of white and dark polycaprolactone trifumarate in situ cross-linkable scaffolds seeded with rat bone marrow stromal cells

OBJECTIVE:

Dark poly(caprolactone) trifumarate is a successful candidate for use as a bone tissue engineering scaffold. Recently, a white polymeric scaffold was developed that shows a shorter synthesis time and is more convenient for tissue-staining work. This is an in vitro comparative study of both the white and dark scaffolds.

METHODS:

Both white and dark poly(caprolactone) trifumarate macromers were characterized via Fourier transform infrared spectroscopy before being chemically cross-linked and molded into disc-shaped scaffolds. Biodegradability was assessed by percentage weight loss on days 7, 14, 28, 42 and 56 (n = 5) after immersion in 10% serum-supplemented medium or distilled water. Static cell seeding was employed in which isolated and characterized rat bone marrow stromal cells were seeded directly onto the scaffold surface. Seeded scaffolds were subjected to a series of biochemical assays and scanning electron microscopy at specified time intervals for up to 28 days of incubation.

RESULTS:

The degradation of the white scaffold was significantly lower compared with the dark scaffold but was within the acceptable time range for bone-healing processes. The deoxyribonucleic acid and collagen contents increased up to day 28 with no significant difference between the two scaffolds, but the glycosaminoglycan content was slightly higher in the white scaffold throughout 14 days of incubation. Scanning electron microscopy at day 1 revealed cellular growth and attachment.

CONCLUSIONS:

There was no cell growth advantage between the two forms, but the white scaffold had a slower biodegradability rate, suggesting that the newly synthesized poly(caprolactone) trifumarate is more suitable for use as a bone tissue engineering scaffold.     

Type I interferons increase host susceptibility to Trypanosoma cruzi infection

Trypanosoma cruzi, the protozoan parasite that causes human Chagas' disease, induces a type I interferon (IFN) (IFN-α/β) response during acute experimental infection in mice and in isolated primary cell types. To examine the potential impact of the type I IFN response in shaping outcomes in experimental T. cruzi infection, groups of wild-type (WT) and type I IFN receptor-deficient (IFNAR(-/-)) 129sv/ev mice were infected with two different T. cruzi strains under lethal and sublethal conditions and several parameters were measured during the acute stage of infection. The results demonstrate that type I IFNs are not required for early host protection against T. cruzi. In contrast, under conditions of lethal T. cruzi challenge, WT mice succumbed to infection whereas IFNAR(-/-) mice were ultimately able to control parasite growth and survive. T. cruzi clearance in and survival of IFNAR(-/-) mice were accompanied by higher levels of IFN-γ production by isolated splenocytes in response to parasite antigen. The suppression of IFN-γ in splenocytes from WT mice was independent of IL-10 levels. While the impact of type I IFNs on the production of IFN-γ and other cytokines/chemokines remains to be fully determined in the context of T. cruzi infection, our data suggest that, under conditions of high parasite burden, type I IFNs negatively impact IFN-γ production, initiating a detrimental cycle that contributes to the ultimate failure to control infection. These findings are consistent with a growing theme in the microbial pathogenesis field in which type I IFNs can be detrimental to the host in a variety of nonviral pathogen infection models.     

Clinical and obstetric characteristics of pregnant women with Covid-19: A case series study on 26 patients

ObjectiveTo evaluate the clinical characteristics and outcomes of pregnant women with Covid-19.Materials and methodsThis case series study was performed to investigate demographic, clinical and obstetric characteristics of 26 pregnant women with COVID-19 referring to a university hospital of Kashan during the epidemic of COVID-19 (March to May 2020).ResultsThe mean gestational age of the patients at admission and delivery was 31.8 ± 5.2 and 36.3 ± 3.4 weeks, respectively. The most common symptoms were fever (96.2%) followed by dyspnea and cough (30.8%). The findings of lung CT scan showed abnormalities confirming the pneumonia in 22 patients (84.6%). Cesarean section was performed in 69.2% of the mothers. The most common maternal–fetal outcome was preterm delivery (38%). Two mothers were transferred to the ICU due to deterioration in clinical condition and they underwent mechanical ventilation without any maternal death. The most common neonatal outcomes were prematurity (38%) and low birth weight (34.6%). No cases of confirmed COVID-19 were observed in the neonates.ConclusionClinical manifestations and laboratory and radiographic findings in pregnant women with COVID-19 are similar to the general population. Common outcomes of pregnancy and delivery in mothers included increased rate of preterm delivery and cesarean section. The most prevalent neonatal outcomes included prematurity and LBW. Careful monitoring of pregnant women with COVID-19 is recommended.     

Characterization of a new begomovirus and a beta satellite associated with the leaf curl disease of French bean in northern India

Begomoviruses are emerging as serious threat to many crops throughout the world particularly in tropical and sub-tropical regions. A leaf curl disease with symptoms typical of infection by many begomoviruses was observed in French bean (Phaseolus vulgaris) at Kanpur, India, during 2010–2012. The disease caused downward leaf curling and made the plants unproductive. The disease was transmitted from infected to healthy plants through whitefly (Bemisia tabaci). The products of five samples digested with EcoRI yielded DNA fragments of about 2.7 kb. The complete sequence of the Fb1 sample comprised 2,741 nucleotides with genome organization typical of begomoviruses having two ORFs in virion-sense and five ORFs in complementary-sense separated by an intergenic region with begomovirus conserved nonanucleotide sequence, TAATATTAC. The complete DNA-A sequence homology was most closely related to Cotton leaf curl Bangalore virus with 80 % nucleotide sequence identity. Based on the demarcation criteria for identifying a begomovirus species, Fb1 is considered as a distinct begomovirus species, named French bean leaf curl virus and designated as FbLCV-[IN:Knp:12]. The complete sequence of associated satellite DNA-β comprises 1,379 nucleotides with single ORF and has 80 % identity with Papaya leaf curl beta satellite. There was no evidence of recombination in DNA-A of FbLCV and associated beta satellite DNA molecule.     

Mosquito larvicidal activity of citrus limonoids against Aedes albopictus

Citrus limonoids, nomilin and limonin, were used for larvicidal assay against Aedes albopictus utilizing WHO methodology. LC_50s were 305.83, 176.08, and 136.07 μM for nomilin and 850.09, 600.72, and 407.09 μM for limonin after 24, 48, and 72 h, respectively. LT₅₀ assays exhibited that Savage citrange oil was the best at all concentrations (400, 500, 600, and 700 ppm) while Fairchild and Cassa grande were the weakest oils at 400 ppm, but at 500, 600, and 700 ppm, Carrizo citrange remained at the bottom with highest LT₅₀ values. Results exhibited that nomilin was more toxic than limonin and therefore provided a clear indication that limonoids in sample oils influenced the potential of respective oil. Out of the 10 tested citrus seed oils, Savage citrange (Citrus sinensis) comprised the maximum amount of limonin (2823.59 μg/ml) followed by grapefruit, Sacaton citrumelo, and Jaffa. When this oil (Savage citrange) was evaluated for bioassay against larvae of Ae. albopictus, it reflected complete dominance (LC₅₀ and LT₅₀) as compared to rest of the oils. Although Jaffa (Citrus paradisi) was found to contain nomilin and limonin, it was found less effective as compared to Savage citrange. The oils from Minneola and Chinese lime did not contain limonin and nomilin, and were therefore weak in terms of LC₅₀ values. Presence of limonin and nomilin in plant products is therefore a significant indicator of the pest control that needs to be exploited in other plants as well.     

The FOUR Score Predicts Mortality,Endotracheal Intubation and ICU Length of Stay After Traumatic Brain Injury

Background

The Glasgow Coma Scale (GCS) is the most widely accepted scale for assessing levels of consciousness, clinical status, as well as prognosis of traumatic brain injury (TBI) patients. The Full Outline of UnResponsiveness (FOUR) score is a new coma scale developed addressing the limitations of the GCS. The aim of this prospective cohort study was to compare the performance of the FOUR score vs. the GCS in predicting TBI outcomes.

Methods

From April to July 2011, 60 consecutive adult patients with TBI admitted to the Alexandria Main University Hospital intensive care units (ICU) were enrolled in the study. GCS and FOUR score were documented on arrival to emergency room. Outcomes were in-hospital mortality, unfavorable outcome [Glasgow outcome scale extended (GOSE) 1–4], endotracheal intubation, and ICU length of stay (LOS).

Results

Fifteen (25 %) patients died and 35 (58 %) had unfavorable outcome. When predicting mortality, the FOUR score showed significantly higher area under receiver operating characteristic curve (AUC) than the GCS score (0.850 vs. 0.796, p = 0.025). The FOUR score and the GCS score were not different in predicting unfavorable outcome (AUC 0.813 vs. 0.779, p = 0.136) and endotracheal intubation (AUC 0.961 vs. 0.982, p = 0.06). Both scores were good predictors of ICU LOS (r ² = 0.40 [FOUR score] vs. 0.41 [GCS score]).

Conclusions

The FOUR score was superior to the GCS in predicting in-hospital mortality in TBI patients. There was no difference between both scores in predicting unfavorable outcome, endotracheal intubation, and ICU LOS.     

Differentiation and proliferation of spermatogonial stem cells using a three-dimensional decellularized testicular scaffold: a new method to study the testicular microenvironment in vitro

International Urology and Nephrology - Successful in vitro transplantation of spermatogonial stem cells (SSCs) demands effective culture systems for SSCs proliferation and differentiation. Natural...     

Effect of the COVID-19 pandemic on CT scans ordered from the emergency department for abdominal complaints

Emergency Radiology - The COVID-19 pandemic has affected healthcare systems and patients alike across the USA. We seek to elucidate changes in abdominal imaging ordered from the emergency...     

The role of matrix metalloproteinase-2 in the culture media in embryo implantation rate in normogonadotrophic cases undergoing ICSI

ObjectiveThe aim of the study is to correlate the changes in the biochemical marker MMP-2 in the culture media with the outcome of normogonadotrophic cases undergoing ICSI.MethodologyA prospective study of infertile females was conducted in El-Shatby Maternity University Hospital between October 2011 and May 2012 utilizing a sample of 40 normogonadotrophic infertile women (22 females with unexplained infertility and 18 females with tubal factor infertility).ResultsClinical pregnancy was 57.5%; 15 out of the 22 females with unexplained infertility and 8 out of the 18 females with tubal factor infertility. There was no abortion, ectopic or chemical pregnancy. Ongoing pregnancy after 14 weeks of gestational age was 100%.Total (MMP-2) ranged between (4.1 and 21.1) and (3.5–37) ng/ml with the mean of (9.91 ± 5.48) and (13.91 ± 8.87) ng/ml for non pregnant and pregnant groups respectively. There were no statistical significant differences between the two groups regarding total MMP-2 (P = 0.055).The mean of MMP-2/embryo/h ranged between (0.05 ± 0.05) and (0.06 ± 0.08) ng/ml/embryo/h for non pregnant and pregnant groups respectively. There were no statistical significant differences between the two groups regarding MMP-2/embryo/h (P = 0.234).ConclusionsMMP-2 concentration in the culture media cannot be used as a biochemical marker for embryo selection or prediction of implantation in the normogonadotrophic cases undergoing ICSI.RecommendationsResults of the present study suggest searching for other markers in the culture media for better embryo selection and for prediction of implantation in the normogonadotrophic cases undergoing ICSI.