scholarly journals Ghrelin and orexin levels in infertile male: evaluation of effects on varicocele pathophysiology, relationship seminal and hormonal parameter

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Üçler Kısa ◽  
M. Murad Başar ◽  
Timuçin Şipal ◽  
Özlem Doğan Ceylan

AbstractObjectiveThe aim of the present study was to investigate serum ghrelin and orexin levels in patients with varicocele and compare these levels with idiopathic infertile male and healthy control cases.MethodsThis study enrolled 24 men with varicocele, 24 males having idiopathic infertility, and 21 fertile men as the control group. Hormonal analyses, ghrelin and orexin levels were measured samples. Semen was analyzed after 3 and 5 days of sexual abstinence.ResultsSerum ghrelin levels were statistically different among the three groups (p=0.015), and it was due to a statistically lower level in group-1 than the level in the control cases (p=0.012). On the other hand, serum orexin levels were lower than healthy subjects in infertile groups with/without varicocele, but there was no difference (p=0.685) among three groups. Serum ghrelin level showed a negative and significant correlation only with sperm motility (r=−0.646, p=0.022), there was no correlation with other parameters. On the other hand, serum orexin levels did not show a significant correlation with seminal parameters.ConclusionBoth new investigated peptides ghrelin and orexin have regulatory effects on testicular function. However, ghrelin has a more obvious and complex effect on spermatogenesis. Impaired seminal parameters, especially motility was associated with increased serum ghrelin levels in infertile patients, especially with varicocele.

2017 ◽  
Vol 7 (2) ◽  
pp. 67 ◽  
Author(s):  
Mehmet Fatih Ocal

Integrating the properties of computer algebra systems and dynamic geometry environments, Geogebra became an effective and powerful tool for teaching and learning mathematics. One of the reasons that teachers use Geogebra in mathematics classrooms is to make students learn mathematics meaningfully and conceptually. From this perspective, the purpose of this study was to investigate whether instruction with Geogebra has effect on students’ achievements regarding their conceptual and procedural knowledge on the applications of derivative subject. This study adopted the quantitative approach with pre-test post-test control group true experimental design. The participants were composed of two calculus classrooms involving 31 and 24 students, respectively. The experimental group with 31 students received instruction with Geogebra while the control group received traditional instruction in learning the applications of derivative. Independent samples t-test was used in the analysis of the data gathered from students’ responses to Applications of Derivative Test which was subjected to them before and after teaching processes. The findings indicated that instruction with Geogebra had positive effect on students’ scores regarding conceptual knowledge and their overall scores. On the other hand, there was no significant difference between experimental and control group students’ scores regarding procedural knowledge. It could be concluded that students in both groups were focused on procedural knowledge to be successful in learning calculus subjects including applications of derivative in both groups. On the other hand, instruction with Geogebra supported students’ learning these subjects meaningfully and conceptually.


2017 ◽  
Vol 14 (4) ◽  
pp. 4561 ◽  
Author(s):  
Hamza Albayrak ◽  
Paşa Yalçın ◽  
Sema Altun Yalçın

In this research, it was aimed to determine the effect of learning stations designed for astronomy subjects on the academic achievement of students and give an alternative method for teaching astronomy in the literature. The mixed approach in which mixed quantitative and qualitative methods were used together was preferred in the study. Among the quantitative methods, the pre-test and post-test model of the semi-experimental method was used; in addition, the protocols were applied about the method, which was used. The research was carried out with 98 seventh class students, who were under education in a secondary school located in the Eastern Anatolia Region of Turkey in the education year of 2015-2016. The quantitative data were analysed via the Astronomy Achievement Test (AAT) developed by the researchers and had 0,795 Cronbach Alpha reliability coefficient. The astronomy subjects in science lesson of the seventh class were studied with the experimental group through the learning stations; on the other hand, they were studied with the students in the control group through the activities stated in the textbook prepared by the Ministry of Education. The AAT was applied for the experimental, control groups using the pre- and post-tests, and data were analysed with the t-test. Meaningful difference was determined in AAT pre-test average scores of experimental and control groups; on the other hand, a meaningful difference was determined between the groups according to the independent samples t-test results applied with the average scores of the post-test(p<0.05). As a result of the analysis of the data gathered with the Station Observation Form (SOF), developed for the research, it was found out that the students recognise the learning stations as a technique of useful, entertaining, engaging, and easy-to-learn that enable them to learn astronomy topics effectively.Extended English abstract is in the end of Full Text PDF (TURKISH) file. ÖzetBu araştırmada, astronomi konuları için tasarlanan öğrenme istasyonlarının öğrencilerin akademik başarılarına etkisini belirlemek ve literatüre astronomi öğretimi için alternatif bir yöntem sunmak amaçlanmıştır.  Araştırmada karma nicel ve nitel yöntemlerin birlikte kullanıldığı karma yaklaşım tercih edilmiştir. Nicel yöntemlerden yarı deneysel yöntemin ön test- son test modeli kullanılmış olup ayrıca uygulanan yöntem hakkında öğrenci görüşmeleri yapılmıştır. Araştırma 2015- 2016 eğitim öğretim döneminde Doğu Anadolu Bölgesinde yer alan bir ortaokulda öğretim gören 98 yedinci sınıf öğrenci ile yürütülmüştür.  Nicel veriler için araştırmacılar tarafından geliştirilen ve cronbac’h alpha güvenlik katsayısı 0.795 olan Astronomi Başarı Testi (ABT) kullanılmıştır.  Yedinci sınıf fen bilimleri dersi içerisindeki astronomi konuları deney grubu ile öğrenme istasyonları yardımıyla, kontrol grubundaki öğrencilerle MEB’in ön gördüğü ders kitabında yer alan etkinlikler takip edilerek işlenmiştir. ABT deney ve kontrol gruplarına ön test- son test olarak uygulanarak t testi ile analiz edilmiştir. Araştırmada deney ve kontrol gruplarının ABT ön test ortalama puanları arasında anlamlı bir farklılık belirlenmişken, son test puan ortalamaları ile yapılan bağımsız örnekler t testi sonuçlarına göre gruplar arasında anlamlı bir farklılık belirlenmiştir (p<0.05). Araştırma için geliştirilen İstasyon Gözlem Formu (İGF) ile elde edilen verilerinin analizi sonucunda öğrenciler öğrenme istasyonlarını, astronomi konuları için etkili öğrenmeyi sağlayan, faydalı, eğlenceli, ilgi çekici ve kolay öğrenmeyi destekleyen bir teknik olarak gördükleri bulunmuştur.


2021 ◽  
Vol 11 (2) ◽  
pp. 193-201
Author(s):  
Nasser Ghanem ◽  
Marwa Said Faheem ◽  
Romysa Samy ◽  
Ashraf Hesham Barkawi

It is documented that heat stress caused impairment on the reproductive performance of dairy animals. However, there are few reports that have focused on the molecular and intracellular responses of in vitro cultured buffalo granulosa cells during heat elevation. The present study was conducted to investigate the effect of heat elevation during in vitro culture of buffalo granulosa cells on their viability, quality, mitochondrial activity, and transcriptional activity. Granulosa cells were harvested after aspiration of cumulus-oocytes complexes that were collected from abattoir ovaries. The granulosa cells were cultured in vitro either at a normal physiological temperature suitable for oocyte maturation and embryo development (38.5°C) or exposed to the elevated temperature of 40.5°C on day 3 of culture (the first two days were for confluence) for two hours of culture then continued at 38.5°C up to day 7 of culture. The viability of granulosa cells was measured using trypan blue and quality was estimated by measuring the level of intracellular reactive oxygen species (ROS) on day 7. Moreover, metabolic activity was performed by measuring the fluorescent intensity of mitochondria. Moreover, transcriptional activity was done by profiling four selected candidate genes using quantitative real-time PCR. The results indicated that the granulosa cells viability rate significantly decreased in the heat stress group (25.1 ± 3.7), compared to the control group (36.6 ± 5.3) on confluence day (day 3). In addition, the viability rate on the last day of culture (day 7) decreased in heat stress, compared to control (83.7 ± 4.5 and 97.4 ± 0.4, respectively). On the other hand, there was a nonsignificant difference in ROS profile between the control (21.7*104 ± 1.3) and the heat-stressed group (15.7 ± 0.7) on day 7 of culture. However, the mitochondrial fluorescent intensity was higher in the control (21.9 ± 1.9) than in the heat-stressed group (15.4 ± 0.8) on day 7 of culture. The expression of cellular defense (HSF1) and apoptosis-inducing gene (P53) were significantly up-regulated in granulosa cells exposed to heat elevation, compared to the control group. On the other hand, the steroidogenesis-regulating gene (StAR) was down-regulated in granulosa cells cultured under heat shock, compared to the control group. In conclusion, heat stress reduced the viability of granulosa cells by inducing the expression of an apoptosis-related gene (P53) and compromised expression of genes regulating the steroid biosynthesis, which resulted in up-regulation of cell defense gene (HSF1) in an attempt to ameliorate the deleterious effect of heat stress on the biological activity of the granulosa cells.


2019 ◽  
Vol 38 (11) ◽  
pp. 1275-1282
Author(s):  
A Pergel ◽  
L Tümkaya ◽  
MK Çolakoğlu ◽  
G Demiral ◽  
S Kalcan ◽  
...  

Carbon tetrachloride (CCL4) is often employed in the production of chlorofluorocarbons, petroleum refining, oil and rubber processing, and laboratory applications. Oral, subcutaneous, and inhalation exposure to CCL4 in animal studies have been shown to be capable of leading to various types of cancer (benign and malignant, liver, breast, and adrenal gland tumors). The present study also evaluated the protective role of infliximab (INF) against the deleterious effects of CCL4 on the intestinal system. Twenty-four male Sprague-Dawley rats were randomly assigned into three groups, control ( n = 8), CCL4 ( n = 8), and CCL4 + INF ( n = 8). The control group received 1 mL isotonic saline solution only via intraperitoneal (i.p.) injection. The CCL4 group received a single i.p. dose of 2 mL/kg CCL4. The CCL4 + INF group received a single i.p. dose of 7 mg/kg INF followed 24 h later by a single dose of 2 mL/kg CCL4. All rats were euthanized 2 days following drug administration. CCL4 group samples also exhibited diffuse loss of enterocytes, vascular congestion, neutrophil infiltration, an extension of the subepithelial space and significant epithelial lifting along the length of the villi with a few denuded villous tips. In addition, CCL4 treatment increased intestinal malondialdehyde (MDA) level and caspase-3 positivity. On the other hand, INF decreased MDA levels, caspase-3 positivity, and loss of villous. Our findings suggest that CCL4 appears to exert a highly deleterious effect on the intestinal mucosa. On the other hand, INF is effective in preventing this CCL4-induced intestinal injury by reducing oxidative stress and apoptosis.


Biologia ◽  
2011 ◽  
Vol 66 (1) ◽  
Author(s):  
Ján Praslička ◽  
Janka Schlarmannová ◽  
Barbora Matejovičová ◽  
Ján Tancík

AbstractThe effectiveness of the predatory mite Typhlodromus pyri and of an application of Polysulphide-Ca was compared during 2006–2008. The experiment showed differences in infestation levels of pear leaves caused by Eriophyes pyri. The highest percentage of leaves with symptoms was found in untreated control group (⊘ 20.9%); the lowest percentage was found in plots treated with T. pyri (⊘ 3.7%); and a slightly higher percentage was found in plots treated with Polysulphide-Ca (⊘ 8.6%). During 2006–2008 the percentage of leaves with symptoms was approximately the same only in the untreated control plots (from 20.3% to 21.5%). The percentage of leaves with characteristic symptoms in plots treated with T. pyri decreased from 5.5% in 2006 to 4.3% in 2007, and to 1.3% in 2008. On the other hand, the percentage of leaves with symptoms in plots treated with Polysulphide-Ca increased from 5.5% in 2006 to 8.5% in 2007, and to 11.8% in 2008. The intensity of symptoms on infested leaves was also different depending on treatments and years. The average biological activity was 82.4% in plots receiving releases of T. pyri and 58.8% in plots treated with Polysulphide-Ca.


2007 ◽  
Vol 19 (1) ◽  
pp. 317
Author(s):  
T. S. Kim ◽  
Y. Cao ◽  
H. T. Cheong ◽  
B. K. Yang ◽  
C. K. Park

Sperm mediated gene transfer (SMGT) is based on the ability of spermatozoa to bind and internalize exogenous DNA and transfer it into the oocytes at fertilization. The purpose of this study was to assess introducing exogenous DNA into boar spermatozoa by DNA solution or DNA/liposome complex under different conditions (period of incubation, exogenous DNA, liposome, and concentration of spermatozoa). Genomic DNA of sperm loaded with DNA by treatment was isolated by alkaline lysis. Quantitation of exogenous DNA amplified by PCR was analyzed by agarose electrophoresis densitometry. The quality of treated spermatozoa under the best conditions or no treatment (control) was evaluated during incubation (0, 2, 4, and 6 h) for viability (SYBR-14/PI), motility (Makler counting chamber), morphology (rose bengal staining), and acrosomal status (Coomassie staining). Sperm loaded with DNA also were used for in vitro fertilization. Immature oocytes incubated in TCM-199 medium for 44 h were fertilized in mTBM medium for 6 h and cultured in PZM-3. Cleavage and development of embryos were assessed on Days 2 and 7 of culture, respectively. Transfection rates at the blastocyst stage were assessed by PCR analysis. Data were evaluated by Duncan&apos;s multiple-range test using the GLM procedure. In the preliminary experiment, DNA uptake of spermatozoa by DNA solution and liposome/DNA complex was completed within 90-120 min. Transfection efficiency of spermatozoa was significantly (P &lt; 0.05) higher in the 105 spermatozoa group than in the other groups (104, 106, and 107 spermatozoa). The transfection efficiency was gradually increased by increasing the concentration of exogenous DNA. On the other hand, viability of transfected spermatozoa by all treatments (control, DNA solution, and DNA/liposome) at 0 h (72.3 � 0.2, 70.8 � 1.8, and 68.0 � 2.2%, respectively) of storage was significantly (P &lt; 0.05) lower than for fresh spermatozoa (83.3 � 1.7%). Survival and motility of all treatments after 4 h of storage were significantly (P &lt; 0.05) lower than at 0 and 2 h. Both abnormality and acrosome reaction of spermatozoa were gradually increased with prolonged storage periods. On the other hand, the cleavage rate of embryos by DNA/liposome complex (56.3 � 2.3%) was significantly (P &lt; 0.05) lower compared to both DNA solution (64.0 � 1.1%) and control (67.8 � 2.3%). The developmental rates of blastocysts were significantly (P &lt; 0.05) lower in the liposome/DNA complex and DNA solution groups (9.1 � 1.3 and 11.3 � 0.8%) than in the control group (22.2 � 0.6%). The transfection rates of blastocysts were higher in the liposome/DNA group (54.3 � 12.0%) than in the DNA solution group (38.7 � 6.6%). These results show that the SMGT method under the control conditions efficiently transfers exogenous DNA into the porcine oocytes. This work was supported by the Research on the Production of Bio-organs (No. 2005 03020302) Ministry of Agriculture and Forestry, Republic of Korea


2010 ◽  
Vol 8 (4) ◽  
pp. 414-418 ◽  
Author(s):  
Darcielle Bruna Dias Elias ◽  
Rivelilson Mendes de Freitas ◽  
Romélia Pinheiro Gonçalves ◽  
Hemerson Yuri Ferreira Magalhães ◽  
Jacqueline Holanda de Sousa ◽  
...  

ABSTRACT Objective: To determine the serum levels of malondialdehyde and nitrite in patients with sickle cell anemia treated or not with hydroxyurea in outpatient's setting. Methods: Of the 65 patients with sickle cell anemia selected for the study, 51 were not treated with hydroxyurea (Group 1), 14 made chronic use of hydroxyurea (Group 2) and 20 individuals had no hemoglobinopathies (Control Group). Results: The Control Group had a lower and more homogeneous concentration of malondialdehyde levels as compared to the other groups. The results of Groups 1 and 2 showed increased values of malondialdehyde levels when compared to the Control Group. Considering the values of Groups 1 and 2, there were no significant changes in the malondialdehyde levels. There was no significant difference in the serum levels of nitrite between the groups. Group 2 presented a statistically significant correlation between serum malondialdehyde levels and the clinical variables investigated. In turn, Group 1 showed correlation only with occurrence of three or more vaso-occlusive crises. There was no correlation between nitrite levels and the clinical variables. Conclusion: The results revealed that during the pathogenesis of sickle cell anemia, an increase in lipid peroxidation was observed. On the other hand, no changes in oxidative parameters were detected during treatment with hydroxyurea, probably due to the short period of treatment of the patients studied.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4441-4441
Author(s):  
Kursat Ozdilli ◽  
Fatma Oguz ◽  
Hulya Bilgen ◽  
Yeliz Duvarci ◽  
Halim Issever ◽  
...  

Abstract Cytokines are chemical mediators between cells and they bind on their own specific receptors on the target cells. Cytokine gene polymorphism may be implicated in the pathogenesis of infections autoimmun disease and malignancies via their effect on cytokine production and regulation. Leukemic cells proliferate under the influence of cytokines. It is known that acute lymphoblastic leukemia (ALL) which is sensitive to some cytokine gene is one of the hematological malignances derived from lymphoid tissue. Our aim is to determined frequencies of selected cytokines (TNF-α, TGF-β, IL-10, IL-6, IFN-γ) in childhood ALL patients and unrelated healthy control groups. We also investigated weather these polymorphism might contribute to the pathogenesis of ALL. Method: Genotyping was performed by polymerase chain reaction with sequence specific primers (PCR-SSP) using “ One lamda” kit in 44 ALL patients and 50 unrelated healthy individuals. Allelic frequencies were determined 24 polymorphism located within 16 cytokine genes. Genotype frequencies between ALL patients and controls were compared using Chi-Square Yates, Fisher’s Exact Tests and Stepwise Logistic Regression Analysis (SLRA). Results: The frequency of TGF-β(TT/GG) allel (29,5% versus 8%, respectively;in chi-square p=0,007,odds ratio=4,82, 95% confidence interval (CI) 1,49–16,16; in SLRA p=0,002, OR=15,26,95% CI 2,77–84,05), TGF-β(TC/GG) allel (36,4% versus 10%, respectively; in chi-square p=0,002,odds ratio=5,14, 95% CI 1,69–15,59; in SLRA p=0,005,OR=10,21, 95% CI 2,02–51,61), IL-6(GC) allel (38,6% versus 8%, respectively; in chi-square p<0,001; odds ratio 7,24; 95% CI 2,20–23,76; in SLRA p=0,02,OR=6,37, 95% CI 1,22–33,15), IL-10(GCC/ATA) allel (36,4% versus 8%, respectively; in chi-square p=0,001, odds ratio 6,57, 95% CI 1,99–21,64; in SLRA p=0,01,OR=8,04, 95% CI 1,40–46,04), IFN-γ(TA) allel (54,5% versus 10%, respectively; in chi-square p<0,001, odds ratio 10,8, 95% CI 3,60–32,40; in SLRA p<0,001,OR=29,43, 95% CI 5,47–158,35) frequencies were found higher in patients with ALL compared to the control group. On the other hand IFN-γ(TT) allel (20% versus 48%, respectively; p=0,005; odds ratio 0,27; 95% CI 0,11–0,70), IFN-γ(AT)(0% versus 22%, respectively; p=0,001; odds ratio 1,28; 95%CI 1,10–1,48; fisher’s exact=0,001) and IL-6(CA)(0% versus 22%, respectively; in chi-square p<0,001; odds ratio 1,28; 95% CI 1,10–1,28; fisher’s exact=0,001) allel frequencies were found higher in the control group compared to the patients with ALL.TNF-α(GG) allel frequency was higher both in patients with ALL and in the control group (72% versus 85%). As a conclusion higher frequency in TGF-b(TT/GG),TGF-b(TC/GG),IL-6(GC), IL-10(GCC/ATA) and IFN-g(TA) allels may predispose to ALL.On the other hand IFN-g(TT), IFN-g(AT) and IL-6(CA) allels might be the preventive factor for ALL The present study is rather significant that it is the study which assessed the relation of the cytokines in patients with ALL compared to the control group taken from the genetic pool of The Turkish population but larger groups of studies must be done in future.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4140-4140
Author(s):  
Satoshi Takahashi ◽  
Jun Ooi ◽  
Seiko Kato ◽  
Toshiro Kawakita ◽  
Arinobu Tojo ◽  
...  

Abstract Abstract 4140 Study purpose: The cell dose of graft is the primary factor to select for cord blood (CB) unit and most of adult patients choose human leukocyte antigen (HLA)-mismatched CB graft. We have performed more than 7,500 CB transplantation (CBT) in Japan. Almost two-third of them has been using 2-loci HLA-mismatched CB unit. The degree of HLA disparity between patient and graft is known to be associated with risks of poor graft function and of graft-versus-host disease (GVHD) on allogeneic hematopoietic stem cell transplantation. On the other hand, those risks of transplant-related complications are not equivalent even among the donor-recipient pairs who have same number of mismatched HLA antigens. The mismatched HLA haplotype could be responsible for post-transplant adverse events because of incompatibility of non-HLA polymorphic genes. Recently, HLA haplotype matching effect on GVHD has been demonstrated in unrelated bone marrow transplantation (S Morishima, et al. Blood 2010). In this study, we have performed the single institutional analysis to determine the impact of HLA haplotype matching in HLA-mismatched CBT. Patients and Methods: We studied the clinical outcomes of 170 consecutive adult patients who received unrelated CBT between August 1998 and January 2011 in the institute of medical Science, University of Tokyo. Patients received previous allogeneic transplants were excluded from this study. All patients received myeloablative regimens including 12 Gy of total body irradiation, cyclosporine plus short term methotraxate for GVHD prophylaxis and almost same supportive care by the institutional protocol. By low-resolution typing method for HLA-A, -B and -DR loci, 6 patients received matched grafts, 57 received 1 antigen-mismatched and 107 received 2 antigens-mismatched grafts in the graft-versus-host (GvH) direction. We have determined the HLA haplotype based on common haplotypes in Japanese population referred from the 11th International Histocompatibility Workshop and other previous reports. We evaluated the impact of haplotype matching on cumulative incidences of hematopoietic recovery, of GVHD, of relapse and of non-relapse mortality (NRM) using the Pepe and Mori's test. Estimates of overall and disease-free survivals were calculated using the Kaplan-Meier method and analyzed by the log-rank test. Results: Thirty-three among all 170 pairs were defined as the haplotype-matched pairs sharing same haplotypes in both grafts and recipients. The age, sex, cytomegalovirus serological status, diagnosis, risk of the disease at the transplant, numbers of total nucleated cells and CD34+ cells at the cryopreserved were not significantly different between both groups with and without matched haplotypes. Engraftment of platelet after CBT tended to be earlier in haplotype-matched group compared with control group among the 1 antigen-mismatched pairs in the host-versus-graft direction (median: 38 days versus 44 days) and among the 2 antigens-mismatched pairs (median: 38 days versus 42 days), but those were not significant. The cumulative incidences of grades III and IV acute GVHD in patients with haplotype-matched (7%) were significantly lower than non-matched group (9%) among 2 antigens-mismatched pairs in the GvH direction (P=0.033). Notably, cumulative incidences of relapse tended to be lower in haplotype-matched patients among this group (3 years cumulative incidences were 7% in haplotype-matched patients versus 21% in non-matched patients, P=0.086). The haplotype matching effects were not observed in survival rates, cumulative incidences of NRM among any HLA-mismatched pairs. Conclusion: Those data suggest that untyped variation carried on the HLA haplotytpe might be better to be matched. The haplotype matching seemed to effect on lower risk of sever acute GVHD, on the other hand, graft-versus-leukemia effect was conserved in the setting of HLA-mismatched CBT. Disclosures: No relevant conflicts of interest to declare.


2017 ◽  
Vol 25 (4) ◽  
pp. 319-340 ◽  
Author(s):  
Nikolina M. Duvall Antonacopoulos

This longitudinal study examined the effect of acquiring a dog using both an indirect and a direct measure of loneliness. The loneliness levels of 31 adults who acquired a dog and a control group of 35 non-dog guardians (non-dog owners) were assessed at baseline and 8 months. Results revealed that changes in loneliness over time differed for the two groups when loneliness was assessed through a 1-item direct measure. Participants who acquired a dog experienced reduced loneliness levels from baseline to 8 months and were less lonely at 8 months than non-dog guardians, even though the two groups did not differ at baseline. On the other hand, when loneliness was assessed through a multi-item indirect measure, acquiring a dog had no effect on loneliness. These results highlight the importance of the type of measure used to assess loneliness when examining changes in loneliness following the acquisition of a companion animal.


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