Integrating social determinants of health in medical education: a bibliometric analysis study

OBJECTIVES

Social determinants of health (SDH) are the prevalent enablers of health among populations, and integrating them in medical education will advance clinical care by integrating social and economic risk data into medical diagnosis and treatment. Despite the numerous publications on SDH and medical education, the publication trends are not known. The study aims to analyse publication trends in integrating SDH into medical education and the corresponding thematic areas.

STUDY DESIGN

This was a bibliometric analysis study.

METHODS

Bibliometric was used. Data from Scopus databases from January 2006 to June 2023 were retrieved with no language restriction. VOSviewer software was used for analysis. Bibliographic coupling was used to identify the clusters of published literature on the integration of SDH into medical education, followed by the analysis of annual distribution and growth trends, authors and co-author relationships and collaborations.

RESULTS

A total of 1047 articles were retrieved. The annual research publication exhibited a swift surge in the studies conducted during the reviewed period. Five clusters of information were derived: relating to curriculum development, community engagement and service-learning, stakeholder collaborations, development of assessment methods and tools for SDH, and the impact of integrating SDH into medical education.

CONCLUSION

Bibliometric analysis has revealed a growing trend in the field of integrating SDH into medical education, and the study has highlighted the research impact through bibliographic coupling by identifying the five thematic areas. This study lays a foundation for advancing knowledge on what has been published and possible areas for improvement in the integration of SDH into medical education.

Mechanical Properties of Bisacryl-, Composite-, and Ceramic-resin Restorative Materials

OBJECTIVE

Resin-based materials used in restorative dentistry are introduced at a fast pace with limited knowledge about their properties. Comparing properties of these materials from different restorative categories is lacking but can help the clinician in material selection. This study aimed to compare mechanical properties and wear resistance of bis-acryl-, composite-, and ceramic-resin restorative materials.

METHODS AND MATERIALS

Bisacryl-resin (Bis-R, LuxaCrown, DMG), composite-resin (Com-R, Filtek Supreme Ultra, 3M Oral Care), and ceramic-resin (Cer-R, Enamic, VITA Zahnfabrik) specimens were prepared for mechanical tests: fracture toughness (FT) with and without initial thermomechanical loading using a mastication simulator, flexural strength (FS), and flexural modulus (FM), compressive strength (CS), and volumetric wear loss measurement. The datasets for FT and wear resistance were each analyzed using two-way ANOVA followed by pairwise comparisons or Tukey testing as appropriate. The datasets for FS, FM, and CS were analyzed using one-way ANOVA followed by the Tukey test.

RESULTS

Analysis of FS, FM, and CS showed significant differences between materials, with all pairwise comparisons between materials showing significance. Analysis of FT resulted in a significant interaction between the material and treatment, with analysis of wear loss showing a significant interaction between the material and the number of cycles.

CONCLUSIONS

Cer-R demonstrated superior FT, CS, and wear resistance compared to Bis-R and Comp-R materials. Fracture toughness of Bis-R increased after thermomechanical loading.

Prenatal intake of omega-3 promotes Wnt/β-catenin signaling pathway, and preserves integrity of the blood-brain barrier in preeclamptic rats

BACKGROUND

Preeclampsia is a systemic, multi-organ endotheliopathy, associated with oxidative injury to the blood-brain barrier (BBB). Preeclampsia initiates a cascade of events that include neuroinflammation. Recently, it was documented that Wnt/β-catenin signaling pathway exerts neuroprotective effects and maintain BBB integrity. We investigate the protective effect of omega-3 against neurovascular complication of preeclampsia and its relation to Wnt/β-catenin signaling pathway.

METHODOLOGY

After confirmation of day 0 pregnancy (G0), 24 adult pregnant female Wistar rats were divided into four groups control pregnant, pregnant supplemented with omega-3, preeclampsia (PE); female rats received N (ω)-nitro-L-arginine methyl ester (L-NAME) (50 mg/kg/day SC from day 7 to day 16 of pregnancy for induction of preeclampsia) and PE rats supplemented with omega-3. The intake of omega-3 started on day zero (0) of pregnancy until the end of the study (144 mg/kg\day orally).

RESULTS

We found that omega-3 supplementation significantly improved cognitive functions and EEG amplitude, decreased blood pressure, water contents of brain tissues, sFlt-1, oxidative stress, proteinuria, and enhanced Wnt\β-catenin proteins. Histological examination showed improved cerebral microangiopathy, increased expression of claudin-1 and -3, CD31, and VEGF in the cerebral cortical microvasculature and choroid plexus in PE rats treated with omega-3. A positive correlation between protein expression level of Wnt \β-catenin and cognitive functions, and a negative correlation between claudin-5 relative expression, claudin-1 and -3 area % from one side and water content of the brain tissues from the other side were observed.

CONCLUSION

Wnt/β-catenin signaling pathway suspected to have an important role to improve BBB integrity. Neuroprotective, antioxidant, and anti-inflammatory effects of omega-3 were observed and can be suggested as protective supplementation for preeclampsia.

Implication of JAK1/STAT3/SOCS3 Pathway in Aging of Cerebellum of Male Rat: Histological and Molecular study

Aging causes morphological and functional changes in the cerebellum. This work aimed to demonstrate the implication of JAK1/STAT3/SOCS3 on aging-induced changes of rat cerebellum. Thirty male rats were divided into: adult (12 months), early senile (24 months) and late senile (32 months) groups. Immunohistochemical reaction of the cerebellum to GFAP and caspase-3 was assessed and the expression of JAK1, STAT3, SOCS3 proteins was also evaluated. TNFα as well as the activities of malondialdehyde (MDA) and reduced glutathione (GSH) in cerebellar tissue were also measured. The cerebellum of late senile rats revealed more degenerative changes than early senile rats in the form of increase in GFAP and caspase-3 immunoreaction. Additionally, there was decrease in JAK1and STAT3 expression in early and late senile rats and increase in SOCS3 when compare early and late senile groups with adult one. Enhancement of TNFα was noticed with aging as well as significant decrease in GSH and increase in MDA in early senile group. Moreover, late senile group revealed significant decrease in GSH and increase in MDA. It could be concluded that aging resulting in variable changes of the cerebellum as detected by morphological changes, immunohistochemical reactions of caspase-3 and GFAP and expression of JAK1/STAT3/SOCS3 proteins. Additionally, inflammatory marker TNFα and the activity of oxidative/antioxidative stress markers; malondialdehyde (MDA) and reduced glutathione (GSH) were also affected with aging.

Cimetidine a promising radio-protective agent through modulating Bax/Bcl2 ratio: An in vivo study in male rats

Radiotherapy is one of the most effective modalities for treatment of neoplastic diseases. Radiation damage is to a large extent caused by overproduction of reactive oxygen species. To improve the therapeutic index, identifying effective substances for prevention or treatment of postirradiation intestinal and bone marrow injury should be prompted. This study was designed to evaluate the protective effects of cimetidine on the in rats exposed to γ-irradiation (5 Gy) and exploring the B-cell lymphoma 2 (Bcl2)/Bcl2 associated X (bax) pathway as a probable underlying mechanism. Eighteen adult male rats were randomly grouped into three: control, untreated irradiated rats, and irradiated rats pretreated with cimetidine. Seven days postirradiation the rats were culled, the bone marrow (BM) and jejunum tissue samples were collected for biochemical, histological, and immunohistological evaluation of BM cell count (BMCs), intestinal fibrosis, oxidative stress, tumor necrosis factor-α, Bcl2, and Bax. Cimetidine pretreatment significantly reversed the loss of BMCs, intestinal lining destruction, and fibrosis seen in the untreated irradiated rats and significantly decreased the underlying oxidative stress, inflammation, and Bax/Bcl2 ratio. There was a significant differential correlation between Bax/Bcl2 ratio, tissue oxidative stress level, and tissue injury. Cimetidine represents a very promising radioprotective agent with a potential differential beneficial effect on both cancer cells (inducing apoptosis) as previously proved through different studies and adjacent healthy cells (providing radioprotection via inhibiting apoptosis) as clearly demonstrated through this study, via its antioxidant effect and subsequent regulation of type 2 apoptotic pathway through modulation of Bax/Bcl2 ratio.

Protective effect of nebivolol on doxorubicin-induced cardiotoxicity in rats

INTRODUCTION

The cardiotoxicity of doxorubicin is incompletely understood. We investigated the prophylactic effect of nebivolol on doxorubicin-induced cardiac toxicity.

MATERIAL AND METHODS

Thirty rats were divided into a control group, doxorubicin-treated group and nebivolol + doxorubicin-treated group. The specimens were examined using H + E and Masson's trichrome, caspase 3, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and tumor necrosis factor factor-α (TNF-α). The mean area percentage of collagen fiber content, caspase-3, eNOS, iNOS and TNF-α immunoactivities was measured.

RESULTS

The doxorubicin-treated group showed marked myocyte distortion and fragmentation, congestion and cytoplasmic lysis in most fibers. These changes were less intense in the nebivolol-treated group. The mean area percentage of collagen fiber in the nebivolol-treated group was non-significantly smaller (p = 0.07) than that in the doxorubicin-treated group. The expression of caspase-3 (p = 0.03), eNOS (p ≤ 0.001), iNOS (p < 0.001) and TNF-α (p = 0.003) immunoreactivity was improved in the nebivolol-treated group.

CONCLUSIONS

Nebivolol exerted a significant protective effect from doxorubicin toxicity. The protective effect appears to be mediated mainly through caspase-3, eNOS, iNOS and TNF-α modulation.

Cross-talk between apelin and vasopressin in response to different osmotic stimuli in type 2 diabetic rats

Apelin, a peptide hormone that has been linked to insulin resistance, obesity and glucose metabolism, coexists with arginine vasopressin (AVP) in hypothalamic magnocellular neurons that control body fluid homeostasis. The significant correlation between serum glucose and serum osmolarity in uncontrolled DM indicates the need for adequate compensation, but how apelin and AVP contribute to this is still unsettled. This study aims to investigate the interaction between apelin and AVP in osmotic regulation in type 2 diabetes mellitus (T2DM), and to explore the underlying mechanism. Forty-eight adult male albino rats were divided into six groups: control (isotonic, ip 0.9% NaCl; hypotonic, ip distilled water; hypertonic, ip 2% NaCl) groups and T2DM (isotonic, hypotonic, hypertonic) groups. Serum levels of AVP, apelin, Na, glucose, serum and urine osmolarity were measured; kidney samples were taken for Aquaporin 2 channels (AQP2) and epithelial sodium channel gamma subunit (ENaCγ) gene expression. Hypothalamic tissue sections were used for immunohistochemical staining of apelin and AVP. Both in control and diabetic groups serum apelin, showed a significant negative correlation with serum AVP (r=-0.533, p≤ 0.001). Serum apelin and AVP were inversely proportional to their hypothalamic protein expression. Serum apelin and AVP were significantly higher in diabetic rats (P= 0.001) yet their percentage change in response to hypo and hyper-osmotic stimuli (1.5±0.7, -0.34±0.15 and -0.38±0.13, 1.95±0.36, respectively) was less pronounced when compared to control rats (3.28±0.52, -0.59±0.12 and -0.45±0.13, 2.58±0.93, respectively). Na and ENaCγ levels significantly increased in hypertonic rats, while AQP2 gene expression significantly increased in hypotonic rats. Both apelin and AVP reacted to osmotic stimuli in T2DM but with less sensitivity than in control rats. In spite of its abnormal increased levels in diabetic rats, apelin maintained its role through counteracting AVP action.

Age-associated functional morphology of thyroid and its impact on the expression of vimentin, cytokeratins and VEGF. The role of nigella in refinement

INTRODUCTION

Aging causes morphological and functional changes in the thyroid gland. Free radicals play a key role in the pathology of normal aging. Vimentin and cytokeratin are cytoskeletal intermediate filaments that are often used as indirect indices of tissue injury. The aim of the study was to clarify the age-related alterations in the structure and function of the thyroid gland. The relationship between oxidative/antioxidative stress markers and cytoskeletal intermediate filaments (vimentin and cytokeratin) and oxidative/antioxidative stress markers as well as vascular endothelial growth factor (VEGF) during aging were elucidated. Finally, the role of Nigella sativa (NS) oil in ameliorating age-related alterations of the structure and function of the thyroid gland was studied.

MATERIAL AND METHODS

Thirty Sprague-Dawley albino rats were divided into five groups: young adult control, young adult NS-treated, late adult control, late adult NS-treated, and senile. The age of young adult, late adult, and senile rats was nearly 7, 18 and 22 months, respectively. NS oil was added to food pellets and was administered at a daily dose of 0.1 g/kg body weight for one month. The thyroid gland was dissected and fixed immediately in 10% formalin saline. The assessment of thyroid structure was based on hematoxylin and eosin, and Masson's trichrome stainings, and histomorphometric analysis of the deparaffinized sections. Localization and distribution of vimentin and cytokeratin filaments was assessed by immunohistochemistry. Measurements of VEGF gene expression by qPCR and oxidative/antioxidative markers (malondialdehyde and glutathione content, superoxide dismutase activity) in thyroid gland homogenates were performed. Serum concentration of thyroid hormones (T3, T4) and TSH were assessed by radioimmunoassay.

RESULTS

Follicles in the late adult control group were dilated and disrupted. Follicular cells showed cytoplasmic vacuolation. Follicles in the thyroids of senile rats were of irregular shape, often with cellular exfoliations. Many follicles were dilated and lined with flattened cells. A notable amelioration of these morphological alterations was observed in late adult NS-treated rats. Decrease in serum T3 and T4 levels and increase in TSH levels were observed in the late adult control and senile groups. A clear shift of the oxidative/antioxidative markers (MDA/ /GSH, SOD) was observed in the late adult control and senile groups in favor of oxidants. Administration of NS to late adult rats resulted in normalization of these parameters. Increased area of collagen fibers, immunoreactivity of vimentin and cytokeratin filaments and VEGF gene expression were observed in the thyroids of late adult and senile rat groups as compared to young animals. The mean number of follicular cells decreased in the late adult control and senile groups. Administration of NS to the late adult rats returned these parameters to the level of the young adult rats.

CONCLUSIONS

Aging-related alterations in both structure and function of the rat thyroid gland that are associated with increased indices of oxidative stress might be abrogated by administration of antioxidative agents present in Nigella sativa oil.

N-acetylcysteine versus progesterone on the cisplatin-induced peripheral neurotoxicity

BACKGROUND

Cisplatin-induced peripheral nerve neurotoxicity (CIPN) is the main obstacle in cisplatin treatment. The aim of this study was to compare the modulatory effects of N-acetylcysteine (NAC) and progesterone on CIPN, because there are scarce literature data on the protective effect of the proge-sterone on the CIPN.

MATERIALS AND METHODS

Twenty-four rats were divided into four groups: control, cisplatin-treated, concomitant cisplatin-treated and NAC-treated, and concomitant cisplatin-treated and progesterone-treated. Electron microscopic, immunohistochemical, real time polymerase chain reaction and histomorphome-tric analysis; oxidative/antioxidative markers (MDA/GSH and SOD), neurotoxic/ neuroprotective markers (iNOS/nNOS), inflammatory mediators (TNF-a and NF-kB) and BAX were done.

RESULTS

The myelin sheath in the cisplatin-treated group elucidated infolding. The myelin was disfigured, degenerated, and extensively split with areas of focal loss. The axoplasm was atrophic. Ballooning and vacuolations of the mitochon-dria with alterations of Remak bundles structures were observed. Fewer of these changes were noted in the NAC and progesterone-treated groups. Decrease of the antioxidant SOD and GSH (81% and 64%) and increase of the oxidant MDA (9 folds), increment of the neurotoxic iNOS (1.9 folds) and decrement of the neuroprotective nNOS (64%) and elevation of the inflammatory mediators' TNF-a and NF-kB (8.3 and 11 folds) in the cisplatin-treated group. Increase of the antioxidant SOD (1.3 and 2.5 folds) and GSH (120% and 79%) and decrease of the oxidant MDA (69% and 88%), decrement of the neurotoxic iNOS (56% and 68%) and increment of the neuroprotective nNOS (1.6 and one folds) and elevation of the inflammatory mediators' TNF-a and NF-kB were observed in the NAC and progesterone-treated groups, respectively.

CONCLUSIONS

The toxic effect of CIPN might be attributed to either oxidative or severe inflammatory stress. Progesterone is efficient in ameliorating these effects; however, NAC is better. (Folia Morphol 2018; 77, 2: 234-245).

Solar drying of whole mint plant under natural and forced convection

Two identical prototype solar dryers (direct and indirect) having the same dimensions were used to dry whole mint. Both prototypes were operated under natural and forced convection modes. In the case of the later one the ambient air was entered the dryer with the velocity of 4.2 m s⁻¹. The effect of flow mode and the type of solar dryers on the drying kinetics of whole mint were investigated. Ten empirical models were used to fit the drying curves; nine of them represented well the solar drying behavior of mint. The results indicated that drying of mint under different operating conditions occurred in the falling rate period, where no constant rate period of drying was observed. Also, the obtained data revealed that the drying rate of mint under forced convection was higher than that of mint under natural convection, especially during first hours of drying (first day). The values of the effective diffusivity coefficient for the mint drying ranged between 1.2 × 10⁻¹¹ and 1.33 × 10⁻¹¹ m² s⁻¹.

Vascular endothelial growth factor A polymorphism and risk of Kaposi's sarcoma herpesvirus viremia in kidney allograft recipients

BACKGROUND

Kaposi's sarcoma herpesvirus (KSHV) causes Kaposi's sarcoma (KS), primary effusion lymphoma, and multicentric Castleman's disease in immunocompromised patients including allograft recipients. Detection of KSHV DNA in blood, as well as host genetic polymorphisms has been found to be associated with an increased risk for KS. We investigated an association between single nucleotide polymorphisms (SNPs) in vascular endothelial growth factor A (VEGFA) gene region and KSHV viremia in kidney transplant recipients (KTR) in Saudi Arabia.

METHODS

In total, 152 KTR who have survived kidney transplantation for at least 6 months were included in the study. KSHV viremia was determined by real-time polymerase chain reaction (PCR). Genotyping of SNPs in the VEGFA region was performed by PCR and direct sequencing, as well as by restriction fragment length polymorphism.

RESULTS

KSHV DNA was detected in 28.9% (n = 44) of the study population. The A-allele at position C172A VEGFA gene promoter region was found to be associated with KSHV viremia (odd ratio [OR] = 4.8, P = 0.005). In addition, the G-allele at position C+405G in the 5'-untranslated region was associated with KSHV viremia in women, but not in men (OR = 3.98, P = 0.004).

CONCLUSIONS

Our results suggest an association of VEGFA polymorphisms with KSHV viremia among KTR in this study population. A limitation of our study is that the results can only be predicated for patients 6 months after kidney transplantation and should be validated in another cohort with larger sample size.

Effect of glucocorticoids on indomethacin-induced gastric ulcer in the adult male albino rat - histological, morphometric and electron microscopy study

INTRODUCTION

Indomethacin is a non steroidal anti-inflammatory drug (NSAID) which is capable of producing injury to gastric mucosa. To prevent of NSAID-induced gastropathy, it is important to evaluate the risk factors. One of them is steroid. The aim is to study time dependent effects of glucocorticoids (GC) on indomethacin induced gastric ulcer.

MATERIAL AND METHODS

Forty-nine albino rats were used. They were divided into control and experimental groups. The experimental group was subgroup I (rats were given indomethacin and were sacrificed 1 day after drug intake), subgroup II (rats were given indomethacin + dexamethasone and were sacrificed 1 day after drug intake), subgroup III (rats were given indomethacin + dexamethasone and were sacrificed 3 days after drug intake) and subgroup IV (rats were given indomethacin + dexamethasone and were sacrificed 7 days day after drug intake). Histological, scanning electron microscopy and morphometric studies were used.

RESULTS

Indomethacin induced gastric ulceration with shredding of the superficial epithelial cells. The fundic glands were dilated in the subgroups II, III, IV. The surface epithelial cells were shredded and the ulcer sizes were big in subgroup IV. All subgroups exhibited abnormal surface epithelial cells within the gastric ulcer area.

CONCLUSIONS

Indomethacin is capable of producing injury to gastrointestinal mucosa. With prolonged use of GC the surface epithelial cells became more affected and the ulcer sizes became bigger. Concomitant use of both medications will delay the healing of the indomethacin induced gastric ulcer and induce more gastric complication.

Metabolomic profiling and antioxidant activity of some Acacia species

Metabolomic profiling of different parts (leaves, flowers and pods) of Acacia species (Acacia nilotica, Acacia seyal and Acacia laeta) was evaluated. The multivariate data analyses such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) were used to differentiate the distribution of plant metabolites among different species or different organs of the same species. A. nilotica was characterized with a high content of saponins and A. seyal was characterized with high contents of proteins, phenolics, flavonoids and anthocyanins. A. laeta had a higher content of carbohydrates than A. nilotica and A. seyal. On the basis of these results, total antioxidant capacity, DPPH free radical scavenging activity and reducing power of the methanolic extracts of studied parts were evaluated. A. nilotica and A. seyal extracts showed less inhibitory concentration 50 (IC50) compared to A. laeta extracts which means that these two species have the strongest radical scavenging activity whereas A. laeta extracts have the lowest radical scavenging activity. A positive correlation between saponins and flavonoids with total antioxidant capacity and DPPH radical scavenging activity was observed. Based on these results, the potentiality of these plants as antioxidants was discussed.

Impact of an educational programme on knowledge, beliefs, practices and expectations about care among adolescent glaucoma patients in Cairo

Glaucoma is a leading cause of blindness worldwide. The aim of the current study was to evaluate the impact of an educational programme on knowledge, beliefs, practices and expectations towards glaucoma and eye care among adolescent patients with glaucoma. A purposive sample of 50 patients with glaucoma aged 12-18 years, attending ophthalmology outpatient clinics in Cairo, Egypt, were given an educational programme focusing on information about glaucoma, correcting patients' incorrect beliefs and expectations, and demonstrations and retraining about eye care. A range of tools was used to assess patients before and after the programme: questionnaire, observation checklist, physical assessment sheet, childrens' depression scale, children manifest anxiety scale, self-esteem inventory and patients' expectations scale. The programme significantly improved patients' knowledge and beliefs about glaucoma and their practices and expectations concerning eye care. Innovative educational programmes about eye diseases are needed to improve patients' knowledge and practices.

Capacitation status of stored boar spermatozoa is related to litter size of sows

Semen parameters can be considered useful predictors of sperm fertility. The objective of this study was to address the question of whether differences in in vivo fertility after the use of different ejaculates could be predicted using sperm kinematics, capacitation status, and sperm penetration ability under commercial pig production conditions. The percentage of capacitated sperm, as assessed by chlortetracycline (CTC) staining, was positively correlated with litter size (p<0.01). Our data suggest that litter size increases in proportion to the number of capacitated spermatozoa. When all semen parameters (kinematics, sperm capacitation status, and sperm penetration ability) and litter size were included in a multiple linear regression analysis, significant associations were found between the percentage of capacitated sperm (B-type), the sperm fertility index as assessed by a sperm penetration assay (SPA), and litter size. This relationship between capacitated sperm and litter size, however, was more predictive for smaller litter groups than larger ones. We found that the percentage of B-type sperm was significantly correlated with historic average litter size. However, there was no significant correlation between the percentage of B-type sperm and historic farrowing rates. To determine the normal range for B-type sperm, the lower limits were established as 30% for small litters (<8 piglets) and 35% for large litters. The overall accuracy of the assay was 92% and 83% for small and large litters, respectively. These results indicate that capacitation status as measured by CTC staining is a useful predictor of sperm fertility, equivalent to SPA. Moreover, original capacitation status exhibited better predictive ability for small litters than for large ones. Therefore, subfertile boars can be identified primarily by capacitation status.

Study of the relationship between electrical and magnetic properties and Jahn-Teller distortion in R(0.7)Ca(0.3)Mn(0.95)Fe(0.05)O(3) perovskites

In this work structural, magnetic and electrical properties of R(0.7)Ca(0.3)Mn(0.95)Fe(0.05)O(3) (R = Pr and Nd) perovskite manganites are presented. Structural characterization of these compounds shows that both have orthorhombic (Pbnm) phase. The Mössbauer spectra show clear evidence of the local structural distortion of the Mn(Fe)O(6) octahedron on the basis of non-zero nuclear quadrupole interactions for high-spin Fe(3+) ions. It was found that the local structural distortion decreases significantly on replacing Pr(3+) by Nd(3+). This replacement dependence of the Jahn-Teller coupling strength estimated from the Mössbauer results was found to be consistent with the electrical and magnetic properties.