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Abstract

Pregnancy-specific protein B (PSPB) is produced by mono and binucleate trophoblast cells in the placenta of ruminants during pregnancy. This study was designed to determine the pattern of serum PSPB in Yankasa ewes during pregnancy and postpartum periods. Mature cycling Yankasa ewes were synchronized and divided into two groups A (n=11) and B (n=13). Group A was bred, while group B was unbred. Blood samples for PSPB assessment were collected from the ewes starting from the day of breeding until 4 weeks post-lambing. All pregnant Yankasa ewes lambed with singleton lambs after an average of 151.18 days. There was a significant (p<0.05) increase in PSPB in pregnant compared with the non-pregnant ewes in the period between 3 weeks post-breeding and 3 weeks post-lambing. Peaks were detected in the first (100.60 ng/ml), second (133.90 ng/ml), and third (114.82 ng/ml) trimesters at 5, 10 and 21 weeks of gestation, respectively, but steadily decreased within 4 weeks (2.38 ng/ml) postpartum. In conclusion, PSPB detected pregnancy in Yankasa ewes from 3 weeks post-breeding with peak levels at 5, 10 and 21 weeks post-breeding in the first, second, and third trimesters, respectively. PSPB decreased gradually after lambing until 4 weeks postpartum.

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an RNA virus, responsible for the current pandemic outbreak. In total, 200 genomes of the SARS-CoV-2 strains from four host organisms have been analyzed. To investigate the presence of the new mutations in the RNA-directed RNA Polymerase (RdRp) of SARS-CoV-2, we analyzed sequences isolated from different hosts, with particular emphasis on human isolates. We performed a search for the new mutations of the RdRp proteins and study how those newly identified mutations could influence RdRp protein stability. Our results revealed 25 mutations in Rhinolophus sinicus, 1 in Mustela lutreola, 6 in Homo sapiens, and none in Mus musculus RdRp proteins of the SARS-CoV-2 isolates. We found that P323L is the most common stabilising radical mutation in human isolates. Also, we described several unique mutations, specific for studied hosts. Therefore, our data suggest that new and emerging variants of the SARS-CoV-2 RdRp have to be considered for the development of effective therapeutic agents and treatments.

Abstract

Diarrhea caused by multidrug-resistant Escherichia coli (E. coli) is an important and common problem in companion animals, especially dogs. Moreover, these dogs may serve as a reservoir of pathogenic strains of E. coli that may cause enteric and extra-intestinal infections in humans and other animals. This study was conducted to investigate the antibiotic susceptibility pattern of E. coli isolates from diarrheic dogs in Maiduguri Metropolis, Borno State, Nigeria. In fecal samples of 200 dogs with diarrhea, 147 E. coli strains (73.5%) were isolated and characterized by the standard bacteriological techniques (culture, biochemical tests, and antimicrobial susceptibility testing). Out of the 147 positive isolates, 45, 50, and 52 were from Elkanemi Park, Magaram, and Sabon gari wards respectively. The isolates show 100% resistance to chloramphenicol, cefuroxime, and ceftriaxone, 96.6% to amoxicillin, and 95.9% to gentamicin, while all (100%) were susceptible to ciprofloxacin. All the isolates showed multiple antimicrobial resistance. The result of the current study showed that dogs in Maiduguri are important reservoirs of multidrug-resistant E. coli. Therefore, it is important to adopt and apply guidelines for the correct use of antimicrobials in small animal practice to reduce the emergence of multidrug resistance among E. coli in companion animals.

Abstract

Bovine rotavirus A (BRVA) is a frequent causative agent of diarrhea in neonatal calves. Accurate and rapid diagnosis is crucial to prevent calf mortality from BRVA induced diarrhea. Currently, variety of diagnostic methods are being used to detect BRVA from calves’ feces: antibody-based rapid test and ELISA, and molecular-based RT-PCR and RT-qPCR. The aim of the study was to evaluate the accuracy (sensitivity and specificity) of the rapid test (Immunochromatography), ELISA, and RT-PCR assays, using RT-qPCR as the gold standard, in detection of BRVA in diarrheic calves’ fecal samples. One hundred (n=100) clinically diarrheic fecal samples were tested with four different diagnostic tools. The percent of samples positive by rapid test, ELISA, RT-PCR and RT-qPCR was 10%, 16%, 17%, and 33%, respectively. The agreement between different assays was 75% to 99%. The highest agreement was observed between ELISA and RT-PCR assay (99%). The lowest agreement was recorded (75%) between rapid test and RT-qPCR. The sensitivity of the rapid test, ELISA, and RT-PCR were 30%, 49%, and 52%, respectively when compared to the reference test (RT-qPCR), whereas specificity was 100% for all assays. In conclusion, none of the frequently used diagnostic tests showed a satisfactory level of sensitivity to identify BRVA in calves’ feces. Therefore, the use of a more sensitive rapid test should be used to identify infected calves in field conditions in order to prevent calf mortality from rotaviral diarrhea.

Abstract

Objectives. Although multiple mechanisms, including autonomic dysfunction, seem to link sleep-disordered breathing (SDB) with dyslipidemia in animal studies, the data in clinical studies are limited. The aim of this study was to explore the association of lipoprotein levels with SDB measures in healthy habitual snorers. We supposed that autonomic dysfunction is the linking mechanism.

Methods. We enrolled 110 previously healthy subjects with complaints of habitual snoring. To assess SDB, polysomnography was performed. Blood samples for the analysis of total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein cholesterol (LDL), and triglycerides (TG) were obtained in a fasting condition after the polysomnography. Baroreflex sensitivity (BRS) was used to assess the autonomic dysfunction.

Results. In stepwise multiple linear regression analysis, minimal nocturnal blood oxygen saturation (beta=–0.240, p=0.020) and neck circumference (beta=0.224, p=0.03) were the only significant contributors in model predicting TG. SDB measures were not identified as significant contributors in models predicting TC, LDL, and HDL. We failed to find any significant difference in BRS in SDB subjects when compared according to the presence or absence of hypercholesterolemia/ hypertriglyceridemia. In SDB subjects, the area under the curve in a receiver operating curve to predict hypercholesterolemia and hypertriglyceridemia by BRS was 0.468 (95% CI: 0.328–0.608) and 0.425 (95% CI: 0.304–0.546), respectively.

Conclusions. Our results suggest that minimal nocturnal blood oxygen saturation is significant contributor in model predicting TG. No significant decrease in BRS was found in SDB subjects with hypercholesterolemia and hypertriglyceridemia. In SDB subjects, the role of autonomic dys-function in the development of dyslipidemia remains controversial.

Abstract

Objective. Clinical use of glucocorticoids is a frequent cause of secondary osteoporosis, which reduces the mineral density of bones and results in pathological fractures. Mechanical stimulation as non-physiological high-frequency vibration with low acceleration prevents the loss of a crystalline component and stimulates the anabolic remodeling of the bone. The aim of the present research was to assess the impact of mechanical vibration on the bone structure in rats, which received glucocorticoids.

Methods. Wistar rats were randomized into three groups: Vehicle control (Veh), Methylprednisolone sodium succinate (Mps), and Mps combined with whole-body vibration (WBV). Rats of Mps+WBV and Mps groups received 3 mg/kg/day of methylprednisolone every other day for 24 weeks and rats of Veh group received 0.9% saline (sodium chloride). The group of rats Mps+WBV was subjected to WBV for 30 minutes per day for five days a week with parameters 0.3 g and frequency 50 Hz. Relative amount of crystalline component and collagen in the bones was determined by X-ray diffraction (XRD) and calcium level – by atomic absorption spectroscopy. Bone tissue metabolism was assessed by determining the concentration of markers, in particular osteocalcin and Tartrate-resistant acid phosphatase (TRAP5b).

Results. Glucocorticoids induced a considerable increase in the rats body mass (+13%) and decreased the content of mineral component in the femoral neck (–17%) in Mps group compared with Veh. The process of the bone metabolism was significantly accelerated, which is proven by an increased level of remodeling markers. It should be mentioned that WBV did not allow significant decrease in mineral component of the bone to 16th week of the experiment compared with Mps group, although these parameters did not achieve the indices in the Vehicle control group (–10%). Our investigation allows to suggest that mechanical high-frequency vibration of low intensity can partially inhibit the harmful consequences of glucocorticoids on bone structure in rats. Despite the positive impact of vibration on the bone tissue after Mps introduction in the 8th–16th week, this influence was not statistically reliable in the 24th week of the experiment.

Conclusions. The results of our investigation on animal model indicate that non-physiological vertical mechanical vibrations are an effective means to prevent loss of a mineral bone component during treatment with glucocorticoids.

Abstract

Objectives. Hungry bone syndrome (HBS) is a severe and underdiagnosed complication of parathyroidectomy in the treatment of primary hyperparathyroidism (PHP) and secondary hyper-parathyroidism to chronic kidney disease (SHP-CKD).

Methods. A longitudinal study was conducted to compare the postoperative outcomes of patients who developed HBS in two different time frames: before and after implementing a protocol with an intensive electrolytic monitoring and an algorithm regarding electrolytic supplementation.

Results. Overall, 77 parathyroidectomies were included. In PHP, a protocol implementation led to an increased admission of patients in the Intermediate Care Unit for intensive electrolytic monitoring (p<0.001) and an increased rate of oral calcium replacement during hospital stay (p=0.013) compared to pre-protocol era. In SHP-CKD, duration of intravenous calcium replacement was reduced (p=0.010). The prevalence of HBS (9.8% in PHP and 58.3% in SHP-CKD) was similar between the two periods, although its diagnosis had an increased trend in PHP since the protocol implementation. None of the diagnosis of HBS was established due to hypocalcemic symptoms in the post-protocol era (contrary to pre-protocol period, p=0.021). Both hypocalcemia length and duration of surgical ward hospitalization were reduced (p=0.047 and p=0.042, respectively).

Conclusions. An improved assessment of hyperparathyroidism and a decrease in HBS severity were noted in the post-protocol era. We strongly recommend the implementation of a standardized protocol with an intensive phosphocalcium monitoring in the high-risk patients who undergo parathyroidectomy due to hyperparathyroidism as it improves the health care and management of HBS.

Abstract

Objectives. Pheochromocytoma (PCC) is a neuroendocrine tumor derived from chromaffin tissue more frequently found in the adrenal medulla. Many discoveries over the last decade have significantly improved our understanding of PCC.

Methods. We retrospectively reviewed all patients with a histological diagnosis of PCC at the Centro Hospitalar Universitario de Sao Joao, a tertiary and university hospital in Oporto, Portugal, between January 2009 and December 2017.

Results. The study group included 33 patients. In most cases the diagnosis was suspected with more than half of patients presenting with hypertension and the third diagnosed during the work-up of an adrenal incidentaloma. About half of the patients was referred for genetic testing and 6 patients had a positive inherited susceptibility genetic pathogenic variant associated with classic cancer predisposition syndromes and also associated with newly described genes. In the incidentaloma group, genetic testing was performed in 3 (9%) patients with only 1 positive result. In the suspected group, 15 (45%) genetic tests were performed.

Conclusions. In contrast to other studies, where only a minority of patients with PCC were referred for genetic counselling, in our study 54% of patients was referred for genetic testing. This study suggests that clinicians were correctly recognizing the need to refer young patients and patients with positive family history. However, opportunities for genetic testing are frequently missed due to low referral rates in patients with apparently sporadic PCC, particularly older than 30 years old. It is imperative that all the providers involved in the multidisciplinary care of patients with pheochromocytomas are aware of the genetic disorders associated with these unique tumors.

Abstract

Objectives. The application of nanoparticles is experiencing a rapid growth, but it faces a problem of their toxicity, especially adverse effects on female reproduction. Food and medicinal plants and their isoflavones can be protectors against environmental stressors, but their ability to abate the adverse effects of nanoparticles has not been studied yet. In the present study, we examined the effect of silver (AgNPs) and titanium dioxide (titania, TiO2NPs) nanoparticles alone or in combination with plant phytoestrogens/antioxidants (resveratrol, diosgenin, and quercetin) on accumulation of nanoparticles, and progesterone release by cultured porcine ovarian granulosa cells.

Methods. Porcine granulosa cells were incubated in the presence of AgNPs or TiO2NPs (0.1, 1, 10 or 100 µg/ml) alone or in combination with resveratrol, diosgenin or quercetin (10 µg/ml) for 48 h. The accumulation of tested nanoparticles by granulosa cells was assessed under light microscope. Progesterone concentration in culture media was measured by ELISA kit.

Results. Cells accumulated both AgNPs and TiO2NPs in a dose-dependent manner. AgNPs, but not TiO2NPs, at highest dose (100 µg/ml) resulted in a destruction of cell monolayer. Both Ag-NPs and TiO2NPs reduced progesterone release. Resveratrol, diosgenin, and quercetin promoted accumulation of both AgNPs and TiO2NPs in ovarian cells and inhibited the progesterone output. Furthermore, resveratrol and diosgenin, but not quercetin, prevented the suppressive action of both AgNPs, and TiO2NPs on progesterone release.

Conclusions. These observations (1) demonstrate accumulation of AgNPs and TiO2NPs in ovarian cells, (2) confirm the toxic impact of AgNPs, and TiO2NPs on these cells, (3) confirm the inhibitory effects of plant polyphenols/phytoestrogens on ovarian steroidogenesis, (4) show the ability of these isoflavones to increase the accumulation of AgNPs and TiO2NPs, and (5) show their ability to reduce the suppressive effect of AgNPs and TiO2NPs on ovarian progesterone release. The suppressive effect of AgNPs and TiO2NPs on ovarian functions should be taken into account by their exposition. However, these adverse effects could be mitigated by some plant isoflavones.