Prediction of Diabetes and Prediabetes among the Saudi Population Using a Non-Invasive Tool (AUSDRISK).

Background and Objectives: Screening for type 2 diabetes mellitus (DM2) aims to identify asymptomatic individuals who may be at a higher risk, allowing proactive interventions. The objective of this study was to predict the incidence of DM2 and prediabetes in the Saudi population over the next five years. Materials and Methods: The study was conducted in the Aseer region through August 2023 using a cross-sectional survey for data collection. A multistage stratified random sampling technique was adopted, and data were collected through face-to-face interviews using the validated Arabic version of the Australian Type 2 Diabetes Risk Assessment Tool (AUSDRISK). Results: In total, 652 individuals were included in the study. Their mean age was 32.0 ± 12.0 years; 53.8% were male, 89.6% were from urban areas, and 55.8% were single. There were statistically significant differences between males and females in AUSDRISK items, including age, history of high blood glucose, use of medications for high blood pressure, smoking, physical activity, and measurements of waist circumference (p < 0.05). Based on AUSDRISK scores, 46.2% of the included participants were predicted to develop impaired glucose tolerance within the coming five years (65.8% among females vs. 23.6%), and 21.9% were predicted to develop DM2 (35.6% among males vs. 6.0% among females); this difference was statistically significant (p = 0.0001). Conclusions: Urgent public health action is required to prevent the increasing epidemic of DM2 in Saudi Arabia.

Spontaneous Reversal of Vitiligo, a Rare Phenomenon Reported in a Case in Saudi Arabia with an Insight into Metabolic Biochemical Derangements.

Background and Objectives: Vitiligo is a skin disorder characterized by hypopigmented macules occurring due to melanocyte destruction. An interplay of several biochemical mechanisms has been proposed to explain the etiopathogenesis of vitiligo, such as genetic, autoimmune responses, generation of inflammatory mediators, oxidative stress, and melanocyte detachment mechanisms. There is no cure for vitiligo; however, pharmacological treatment measures (cosmetic camouflage creams, steroids, psoralen and ultraviolet A (PUVA) therapy, narrowband UVB) are available, but they could have certain side effects. We reported an interesting case of vitiligo in Saudi Arabia that showed reversal of vitiligo, which is an extremely rare phenomenon, with the objective of probing the probable reasons for this reversal. To the best of our knowledge, there is no study on vitiligo that has reported spontaneous reversal of vitiligo in Saudi Arabia so far. Materials and Method: The patient presented to the Family Medicine clinic with a history of restoration of melanin pigment in his lesions after 3 years of the onset of vitiligo. Patients history was taken carefully along with clinical examination, carried out necessary biomedical lab investigations and compiled the data. The data at the time of pigment restoration were compared to the previous data when he developed the lesions. Result: The probable reasons for vitiligo reversal could be markedly decreased psychological stress, regular consumption of an antioxidant-rich herbal drink made of curcumin and honey, and dietary switchover to vegetarianism and an alcohol-free lifestyle. Conclusions: Curcumin-based herbal remedies could be an alternative option to treat vitiligo. These methods must be further explored through clinical trials as they are safer, easily available, and more affordable.

Prognostic significance of ischemic electrocardiographic changes with regadenoson stress myocardial perfusion imaging.

BACKGROUND: In patients undergoing regadenoson SPECT myocardial perfusion imaging (MPI), the prognostic value of ischemic ST-segment depression (ST↓) and the optimal ST↓ threshold have not been studied. METHODS: A retrospective cohort study of consecutive patients referred for regadenoson stress MPI was conducted. Patients with uninterpretable ECG were excluded. Two diagnostic thresholds of horizontal or downsloping ST↓ were studied, ≥ 0.5 mm and ≥ 1.0 mm. The primary endpoint was the composite major adverse cardiac events (MACE) of cardiac death, myocardial infarction, or coronary revascularization. RESULTS: Among 8615 subjects (mean age 62 ± 13 years; 55% women), 89 (1.0%) had ST↓ ≥ 1.0 mm and 133 (1.5%) had ST↓ ≥ 0.5 mm. Regadenoson-induced ST↓ was more common in women (P < .001). Mean follow-up was 2.5 ± 2.2 years. After multivariate adjustment, ST↓ ≥ 1.0 mm was associated with a non-significant increase in MACE risk (P = .069), irrespective to whether MPI was abnormal (P = .162) or normal (P = .214). Ischemic ST↓ ≥ 0.5 mm was independently associated with MACE in the entire cohort (HR 2.14; CI 1.38-3.32; P = .001), whether MPI is normal (HR 2.07; CI 1.07-4.04; P = .032) or abnormal (HR 2.24; CI 1.23-4.00; P = .007), after adjusting for clinical and imaging covariates. An ST↓ threshold of ≥ 0.5 mm provided greater incremental prognostic value beyond clinical and imaging parameters (Δχ2 = 12.78; P < .001) than ≥ 1.0 mm threshold (Δχ2 = 3.72; P = .093). CONCLUSION: Regadenoson-induced ischemic ST↓ is more common in women and it provides a modest independent prognostic value beyond MPI and clinical parameters. ST↓ ≥ 0.5 mm is a better threshold than ≥ 1.0 mm to define ECG evidence for regadenoson-induced myocardial ischemia.

Trends in complete heart block after transcatheter aortic valve replacement: A population based analysis.

OBJECTIVES: To define the national rate of complete heart block (CHB) after transcatheter aortic valve replacement (TAVR) and its impact on procedural mortality, overall cost, and length of hospital stay. BACKGROUND: CHB leading to permanent pacemaker (PPM) implantation is one of the most common complications post TAVR. National data on the temporal trend of CHB post TAVR are lacking. METHODS: We queried the 2012-2014 National Inpatient Sample databases to identify all patients who underwent TAVR. Patients with preoperative pacemakers or implantable cardioverter-defibrillators were excluded. Association between CHB and outcomes, and overall trends in rate of CHB, PPM implantation, and inpatient mortality were examined. RESULTS: Of 35,500 TAVR procedures, 3,675 (10.4%) had CHB. Overall, occurrence of CHB significantly increased from 8.4% in 2012 to 11.8% in 2014 (adjusted OR per year: 1.23; 95% confidence interval [CI]: 1.17-1.29, P trend <0.001). During the same period, PPM implantation increased from 9.5 to 13.7% (adjusted OR per year: 1.22; 95% CI: 1.16-1.28, P trend <0.001). Patients with CHB had higher odds of in-hospital mortality when compared to patients without CHB (5.9% vs. 4.2%, adjusted OR: 1.32; 95% CI: 1.12-1.56; p = 0.001). Moreover, CHB was also associated with longer length of stay (LOS) and higher hospitalization cost. CONCLUSIONS: There was a significant increase in rates of CHB and PPM implantation over the study period. Development of CHB was associated with increased in-hospital mortality, LOS, and hospitalization cost.

Rate and impact of venous thromboembolism in patients with ST-segment elevation myocardial infarction: Analysis of the Nationwide Inpatient Sample database 2003-2013.

Venous thromboembolism (VTE) and coronary artery disease are major health issues that cause substantial morbidity and mortality. New data have emerged suggesting that these two conditions could have a close relationship. Thus, we sought to determine the trends in annual rate of VTE occurrence in patients with ST-segment elevation myocardial infarction (STEMI) and measure its impact on in-hospital mortality, bleeding complications, and cost and length of hospitalization. We queried the 2003-2013 Nationwide Inpatient Sample databases to identify adults with primary diagnosis of STEMI. VTE events were then allocated. Inpatient outcomes of patients with VTE were compared to those without VTE. Out of 2,495,757 hospitalizations for STEMI, VTE was diagnosed in 25,149 (1%) hospitalizations. Patients who experienced VTE were older (mean age: 67.5 vs 64.8, p < 0.01) and had a higher proportion of black patients (10.1% vs 7.7%, p < 0.001) and females (40.1% vs 35%, p < 0.001) compared to patients without VTE. There was an increasing trend in the rate of VTE during the study period (2003: 0.8% vs 2013: 1.0%, p < 0.001). Patients with VTE had a prolonged hospitalization (median: 9 vs 3 days, p < 0.001), increased cost, higher risk of gastrointestinal bleeding (OR: 2.13, p < 0.001), intracranial hemorrhage (OR: 2.14, p < 0.001), blood transfusions (OR: 1.94, p < 0.001), and mortality (OR: 1.39, p < 0.001). The rate of VTE occurrence in patients with STEMI in our study was 10 per 1000 admissions. VTE was associated with more bleeding complications, longer hospital stays, higher costs, and mortality. These findings suggest that a more aggressive approach for VTE prophylaxis may be warranted in this population.

Resilient design in nuclear energy: Critical lessons from a cross-disciplinary analysis of the Fukushima Dai-ichi nuclear accident.

This paper presents a multidisciplinary analysis of the Fukushima Dai-ichi Nuclear Power Plant accident. Along with the latest observations and simulation studies, we synthesize the time-series and event progressions during the accident across multiple disciplines, including in-plant physics and engineering systems, operators' actions, emergency responses, meteorology, radionuclide release and transport, land contamination, and health impacts. We identify three key factors that exacerbated the consequences of the accident: (1) the failure of Unit 2 containment venting, (2) the insufficient integration of radiation measurements and meteorology data in the evacuation strategy, and (3) the limited risk assessment and emergency preparedness. We conclude with new research and development directions to improve the resilience of nuclear energy systems and communities, including (1) meteorology-informed proactive venting, (2) machine learning-enabled adaptive evacuation zones, and (3) comprehensive risk-informed emergency planning while leveraging the experience from responses to other disasters.

Diabetes and prediabetes prevalence through a community-based screening initiative in Alqunfudah, Saudi Arabia.

Aim: This study aimed to identify prediabetic and diabetic patients using fasting blood sugar in Alqunfudah, Saudi Arabia. Patients & methods: Multistage stratified random sampling technique was used to recruit study participants aged 18 years and older. We measured anthropometric measures like waist circumference and body mass index. Results: A total of 332 participants were included in this study, 52.4% were female, 45.2% aged >50 years, 89.8% were Saudi, and 19.0% had been diagnosed with hypertension. Nearly a third (36.1%) of the participants were diagnosed with Type 2 diabetes mellitus and 28.3% had impaired fasting glucose. Age and hypertension were significant predictors of diabetes. Conclusion: Early detection and intervention are crucial to reducing the diabetes epidemic in Saudi Arabia.

Type 2 diabetes mellitus (T2DM) is a widespread health concern. Saudi Arabia is among the countries with the highest prevalence of diabetes. We conducted a cross sectional study in Alqunfudah, Saudi Arabia, to identify apparently healthy individuals who had undiagnosed T2DM and prediabetics. Through community engagement, we carefully selected apparently health participants from the general population in Alqunfudah, regardless of age or nationality. We measured various health indicators like waist circumference, body mass index, blood pressure, and fasting blood sugar levels. We included 332 participants in our study. Among them, slightly more than half were women, and a large sector was over 50 years old. Most of the participants were Saudi, and some had been diagnosed with hypertension. When we measured fasting blood sugar levels, we found that a considerable portion had T2DM, while others had impaired fasting blood sugar (prediabetic), indicating a risk of developing T2DM. Additionally, our analysis revealed that factors such as age and hypertension were associated with the diagnosis of T2DM. Our study highlights a significant prevalence of asymptomatic T2DM and prediabetes among the general population in Alqunfudah, Saudi Arabia. Early detection and intervention are critical for managing these conditions effectively. We recommend that local health authorities consider implementing screening programs for T2DM and prediabetes through community-based approaches to identify and assist people at risk.

Study in Alqunfudah, Saudi Arabia uncovers a concerning prevalence of diabetes & prediabetes in the general population. Early detection is vital. Urging local health authorities to initiate screening programs for early intervention using community engagement-based approach. #Diabetes #PublicHealth. More support is needed. #Obesity #community engagement.

Exploring the self-efficacy of patients with diabetes: its role as a predictor of diabetes management and well-being.

Background: Self-efficacy is a popular psychological concept that refers to an individual's perception or belief in his ability to perform specific actions. This study aimed to assess the predictive value of self-efficacy, measured using the Self-Efficacy for Managing Chronic Disease 6-Item Scale (SEM6S) questionnaire, for diabetes management and overall well-being in patients with diabetes. Subject and methods: An anonymous online cross-sectional study was conducted to evaluate the self-efficacy of diabetic patients in the Asser region of Saudi Arabia. The participants were requested to upload their most recent glycated hemoglobin A1C (HbA1C) measurements taken in the last three months, which helped in the accurate categorization of their diabetes as either controlled or uncontrolled. We used the valid Arabic version of the SEM6S and WHO-5 well-being questionnaires to assess patient self-efficacy and well-being. Results: A cohort of 342 patients was enrolled in the study, 67.25% were married, their mean age was 43.17 ± 17.61 years, and 52.69% had university-level or higher education. Among the participants, 46.0% exhibited well-being, while 24.9% reported poor well-being, including 9.4% who were identified as experiencing depression. The mean scores of self-efficacy and well-being were significantly higher among those with controlled diabetes versus uncontrolled diabetes (40.86 ± 13.26 vs. 36.48 ± 13.26) and (67.35 ± 21.22 vs. 60.93 ± 25.05), respectively. The predictors of glycemic control were self-efficacy [Odds ratio (OR)=1.03 (95%CI, 1.01-1.06, P=0.002], having other chronic diseases [OR=3.25 (95%CI), P<0.001], having type 1 diabetes [OR=7.16, 95%CI, P=0.005], being Saudi [OR=7.67, (95%CI, P=0.027], working in a public sector [OR=0.15, (95%CI, 0.05-0.44), P=0.005], being unemployed [OR=0.19, (95%CI, 0.06-0.59), P=0.005], being a smoker [OR=0.44, 95%CI, 0.19-0.98, P=0.048], and duration of diabetes between 6-10 years [OR= 0.33, 95%CI, 0.11-0.95), P=0.043] or more than 10 years OR=0.32, 95%CI, 0.12-0.86), P=0.026]. The main determinants of well-being were having self-efficacy [OR=1.07 (95%CI, 1.04-1.09), P = 0.0001], having public health insurance [OR=4.36 (95%CI, P=0.015], and education level (read and write) [OR=0.13 (95%CI,.02-.70), P=0.021]. Conclusions: The study reveals that non-modifiable and modifiable factors, including self-efficacy, play a crucial role in diabetes control. The study recommends providing targeted educational interventions, using different social media platforms, psychosocial support programs, and inclusive healthcare policies to improve diabetes control and mental well-being among diabetic patients.

Exploring the burden of irritable bowel syndrome among university students in Saudi Arabia: A study on prevalence, psychological associations, and well-being.

Patients with irritable bowel syndrome (IBS) experience not only a detrimental impact on their physical health but also a significant influence on their psychological well-being. This study aimed to assess the prevalence of IBS among university students, investigating the sociodemographic and lifestyle factors influencing its onset. Furthermore, it explored the potential impact of psychological factors such as depression, anxiety, and overall well-being on the prevalence of IBS. A cross-sectional analytical study was conducted at Saudi Arabian universities in November and December 2023. To collect data, an anonymous, validated, predesigned questionnaire was used. The diagnosis of IBS was carried out using the validated Arabic version of the Rome IV questionnaire. We used the Arabic version of the World Health Organization Well-being Index to assess the participants' well-being. We used the Arabic version of the Hospital Anxiety and Depression Scale (HADS) to identify people who show clinically significant symptoms of anxiety and depression. Our study included a total of 379 university students, 46.7% were female 86.0% of participants resided in urban areas, and 7.2% had been previously diagnosed with IBS. The prevalence of IBS among participants was found to be 31.9%. We observed a significant association between marital status and IBS (χ2 = 3.95, P = .047). Furthermore, the highest prevalence of IBS was observed among students majoring in literary and scientific disciplines (χ2 = 0.952, P = .049). Individuals with IBS demonstrate a significantly higher prevalence of anxiety (71.90% vs 41.09%, P < .001) and depression (64.46% vs 42.64%, P < .001) compared to those without IBS. Furthermore, people with IBS had a slightly higher prevalence of poor well-being (38.84%) compared to those without IBS (33.72%), but this association was not statistically significant. In multivariate analysis, having a family history of IBS [OR = 1.75 (95% CI, 1.06-2.87), P = .029] having borderline anxiety [OR = 7.58, 95% CI (2.12-27.06), P = .012] and anxiety [OR = 16.07, 95% CI (4.57-56.52), P < .001], and depression [OR = 2.97, 95% CI (1.13-7.83), P = .010] were the main significant predictors of IBS among university students. The high prevalence of IBS among university students was associated with a family history of IBS as well as depression and anxiety. Increasing awareness, multidisciplinary support, and access to mental health services is required to ensure university students' well-being.

Knowledge of Diabetes Mellitus and Practices Regarding Lifestyle Factors and Diabetes Management in a General Adult Population of Aseer Region, Saudi Arabia.

Introduction: Many studies report a lack of public awareness of the risk factors and complications of Diabetes Mellitus. Adequate glycemic control is crucial in preventing or delaying the onset of type 2 diabetes complications, and medication adherence is one of the key factors in achieving this goal. This study aimed to measure the knowledge about diabetes mellitus and practices regarding lifestyle factors and diabetes management in the study population in the Aseer region, of Saudi Arabia. Material and Methods: A descriptive cross-sectional survey was conducted in Abha, a city in the Aseer region of Saudi Arabia. The general population of 18 years of age and above, who were residing in the study area during the period of study, ie, January 2023 to June 2023, were included. The questionnaire was distributed through social media and e-mail for data collection. The descriptive variables were presented using frequency, percentage, and graphs. Pearson's chi-square test was used at a 5% level of significance. Multivariate tests were applied to further explore the findings of univariate analysis. The data were analyzed using SPSS version 20.0. Results: Out of the total 348 participants, a higher proportion was males (56.3%). About 78.7% of the participants were ever diagnosed with diabetes mellitus and 21.3% were never diagnosed with diabetes mellitus. Nearly 31.6% knew that the major cause of diabetes mellitus was obesity and 31.3% knew that it was a hereditary disease. About 42.2% of respondents exercised regularly and 27.6% were smokers. Adherence to prescribed anti-diabetic medications was seen in 63.2% of the respondents. Self-alterations in the timing and dose of prescribed anti-diabetic drugs were seen in 36.5% and 34.8%, respectively. About 60.1% had a moderate level of self-rated knowledge about Diabetes Mellitus, and 27.6% and 12.4% had good and poor self-rated knowledge levels of Diabetes mellitus, respectively. On multivariate analysis, the age group 60-69 years had significant variations as compared to the other age groups on DM, bachelor's degree holders had significant variations as compared to other education variables, being married had significant differences as compared to those unmarried, those employed had significant variations as compared to the other occupation categories, and smokers had a significant impact on DM as compared to non-smokers. Conclusion: Findings indicated less number of respondents exercised regularly, low adherence to prescribed anti-diabetic medications and low levels of self-rated knowledge of diabetes mellitus. Enhancing the patients' knowledge of diabetes mellitus and improving their self-management and adherence to its medications is necessary through public health education.

Factors associated with the knowledge of obstetric danger signs among pregnant women attending primary health care antenatal care clinics in Abha city.

Introduction: Knowledge of obstetric danger signs would equip women to make the right decisions and appropriate actions timely to have better health care assistance which will impose a significant impact on maternal mortality and morbidity. Hence, this study aimed to know the factors associated with the knowledge of obstetric danger signs among pregnant women who attend the primary health care clinics, which is considered as the first gate to seek health care for pregnant women during antenatal checkups. Methodology: This is a cross-sectional study conducted among 400 pregnant women selected by simple random sampling technique who were attending antenatal clinics at primary health care centers at Abha City by using an interview-based questionnaire.cores of <50%, 50-75%, and >75% were considered to be poor, intermediate, and good scores. Frequencies and percentages were used for descriptive variables, whereas for association, tests of significance (Chi square, t-test, and F-test) were applied. Results: Almost 70.8% of participants received health information on obstetric danger signs. The main sources of information were the Internet (23%), family, relatives or friends (17%), and health care providers. The highest participants' correct responses regarding obstetric danger signs were related to severe vaginal bleeding (93.5%), convulsions (76.8%), and decreased fetal movements (76.5%). Proportions of participants with poor knowledge showed an inverse and significant increase with their educational levels (P < 0.001). The highest percentage of poor knowledge grade was observed among participants with no children (54.6%). Participants who received previous information on danger signs had significantly better knowledge grades than those who have not received previous information (P < 0.001). Conclusions: Women's knowledge was suboptimal regarding obstetric danger signs. 30% of women did not receive information about danger signs. Health education provided on obstetric danger signs to pregnant women should be enforced to those who are illiterate, are unemployed, have a low family income, and are with no or less previous pregnancies.

Nuclear waste Educator's workshop: What and how do we teach about nuclear waste?

A workshop was held at the Massachusetts Institute of Technology (MIT) on July 25th and 26th, 2022. The objective was to develop a blueprint for educating next-generation engineers and scientists about nuclear waste management and disposal, which requires knowledge from diverse disciplines, including nuclear, chemical, civil, environmental, and geological science and engineering. The 49 participants included university professors, researchers, industry experts, and government officials from different areas. First, we have developed a list of key fundamental knowledge on waste management and disposal across the nuclear fuel cycle. In addition, we discussed strategies on how to teach students with diverse backgrounds through innovative teaching strategies as well as how to attract students into this area. Through the workshop, we identified the critical needs to (1) develop community resources for nuclear waste education; (2) synthesize historical perspectives, including past contamination and the management of general hazardous waste; (3) emphasize a complete life-cycle perspective, including proper waste management as the key component for energy sustainability; (4) teach students how to communicate about the key facts and risks to technical and non-technical audiences; and (5) accelerate the use of the state-of-art-technologies to attract and retain a young workforce. Furthermore, we aim to build a diverse, inclusive community that supports students in developing their own narratives about nuclear waste, particularly in recognizing that antagonistic views have been important to improving safety and protecting public health and the environment.

Impella in Acute Myocardial Infarction Complicated by Cardiogenic Shock: History and Current Controversies.

In this review, the authors discuss a brief history of the Impella mechanical circulatory support device, a mechanistic role for the device in the context of the underlying pathophysiology of acute myocardial infarction cardiogenic shock (AMI-CS), the current body of literature evaluating its role in AMI-CS, and upcoming efforts to identify a role more clearly for the device in AMI-CS.

Posterior reversible encephalopathy syndrome after liver transplantation in children: a rare complication related to calcineurin inhibitor effects.

PRES is a neuroclinical and radiological syndrome that results from treatment with calcineurin inhibitor immunosuppressives. Severe hypertension is commonly present, but some patients may be normotensive. We report herein two children who received liver transplants, as treatment for biliary atresia in the first case and for Alagille's syndrome in the second one. In the early postoperative, both patients presented hypertension and seizures. In both cases, the image findings suggested the diagnosis of PRES. The CT scan showed alterations in the posterior area of the brain, and brain MRI demonstrated parietal and occipital areas of high signal intensity. Both children were treated by switching the immunosuppressive regimen and controlling arterial blood pressure. They displayed full recuperation without any neurologic sequelae. Probably, the pathophysiology of PRES results from sparse sympathetic innervation of the vertebrobasilar circulation, which is responsible for supplying blood to the posterior areas of the brain. In conclusion, all liver-transplanted children who present with neurological symptoms PRES should be considered in the differential diagnosis, although this is a rare complication. As treatment, we recommend rigorous control of arterial blood pressure and switching the immunosuppressive regimen.

Toward Brief Dual Antiplatelet Therapy and P2Y12 Inhibitors for Monotherapy After PCI.

The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention remains a controversial topic. The European Society of Cardiology and the American College of Cardiology/American Heart Association recommend at least 6 and 12 months of DAPT after PCI in patients with stable coronary artery disease or acute coronary syndrome, respectively. Although prolonging DAPT duration reduces ischemic events, it is associated with higher rates of bleeding and possible fatal outcomes. The DAPT score can be an important tool to identify patients who may still benefit from prolonged therapy. Nevertheless, several recent randomized controlled trials showed that shortening DAPT duration from 12 to 1-3 months reduces bleeding rates without significantly increasing ischemic event rates. These trials also suggested replacing acetylsalicylic acid (aspirin) with P2Y12 inhibitors after short-term DAPT. We review and compare past and present studies regarding DAPT and analyze the evidence favoring a short DAPT duration and the long-term single antiplatelet agent of choice.

Hydrogels for Advanced Stem Cell Therapies: A Biomimetic Materials Approach for Enhancing Natural Tissue Function.

Stem-cell-based therapy is a promising approach for the treatment of a myriad of diseases and injuries. However, the low rate of cell survival and the uncontrolled differentiation of the injected stem cells currently remain key challenges in advancing stem cell therapeutics. Hydrogels are biomaterials that are potentially highly effective candidates for scaffold systems for stem cells and other molecular encapsulation approaches to target in vivo delivery. Hydrogel-based strategies can potentially address several current challenges in stem cell therapy. We present a concise overview of the recent advances in applications of hydrogels in stem cell therapies, with a focus particularly on the recent advances in the design and approaches for application of hydrogels in tissue engineering. The capability of hydrogels to either enhance the function of the transplanted stem cells by promoting their controlled differentiation or enhance the recruitment of endogenous adult stem cells to the injury site for repair is also reviewed. Finally, the importance of impacts and the desired relationship between the scaffold system and the encapsulated stem cells are discussed.

Bibliometric Analysis of the Top 100 Most Cited Articles in the First 50 Years of Heart Transplantation.

The world celebrates over 50 years since the first human-to-human heart transplant. Bibliometric analysis is a statistical concept that has recently evolved, enabling scientists to study citation patterns and identify characteristics of highly cited scholarly work in different fields. Although it has been widely utilized, such analyses have not been conducted to date on heart transplant literature. We sought to assess the characteristics of the top 100 most referenced citations in the field of heart transplantation. We searched the Scopus database (www.scopus.com) to identify all articles relating to heart transplantation. The articles were arranged in descending order from most cited to least cited and selected articles were scrutinized for data extraction. One hundred articles were included in the final list. Of the total 40,660 citations identified, 3,210 (8.0%) were self-citations, which impacted the final rank order. The articles were published in 25 different journals between 1960 and 2013. The most productive 5-year time period was between 2000 and 2005, when 24 of the 100 most cited publications were produced. There was no correlation between the journals' impact factors and the number of articles produced per journal. The presence and type of funding were not associated with the number of citations. Over 85% of first and senior investigators were men. In conclusion, our study highlights key features of the most highly cited scientific literature on heart transplantation and provides insights into trends of published work in this field. Additionally, this work may serve as a useful guide to researchers and funding bodies by highlighting the most prolific areas of cardiac transplant research to date.

Polysaccharides and lignin based hydrogels with potential pharmaceutical use as a drug delivery system produced by a reactive extrusion process.

Currently, there is very strong interest to replace synthetic polymers with biological macromolecules of natural source for applications that interact with humans or the environment. This research describes the development of drug delivery hydrogels from natural polymers, starch, lignin and hemicelluloses by means of reactive extrusion. The hydrogels show a strong swelling ability dependent on pH which may be used to control diffusion rates of water and small molecules in and out of the gel. Also the hydrogels degradation rates were studied in a physiological solution (pH 7.4) for 15days. The results indicated that for all three macromolecules, lower molecular weight and higher level of plasticizer both increase the rate of weight loss of the hydrogels. The degradation was extremely reduced when the polymers were extruded in the presence of a catalyst. Finally the dynamic mechanical analysis revealed that the degradation of the hydrogels induce a significant reduction in the compressive modulus. This study demonstrates the characteristics and potential of natural polymers as a drug release system.

A Review of Water-Resistant Hemicellulose-Based Materials: Processing and Applications.

Hemicelluloses, due to their hydrophilic nature, may tend to be overlooked as a component in water-resistant product applications. However, their domains of use can be greatly expanded by chemical derivatization. Research in which hydrophobic derivatives of hemicelluloses or combinations of hemicelluloses with hydrophobic materials are used with to prepare films and composites is considered herein. Isolation methods that have been used to separate hemicellulose from biomass are also reviewed. Finally, the most useful pathways to change the hydrophilic character of hemicelluloses to hydrophobic are reviewed. In this way, the water resistance can be increased and applications of targeted water-resistant hemicellulose developed. Several applications of these materials are discussed.

Enzymatic degradation of hydroxypropyltrimethylammonium wheat starches.

The enzymatic degradation of hydroxypropyltrimethylammonium modified starches synthesised by dry process was compared with that of hydroxypropyltrimethylammonium modified starches synthesised in glycerol-water plasticised molten medium. The enzymatic degradation rate of products from both origins decreased as the degree of substitution increased. However, two distinct enzymatic degradation profiles were obtained. Dry process products displayed a regular decrease pattern as DS increased. Molten medium synthesised cationic starches displayed a constant degradation level on a wide DS range with alpha,beta-amylase and amyloglucosidase, whereas isoamylase degradation rapidly reached its degradation limit at DSs 0.05. The various plasticising conditions used to synthesise cationic starch in molten medium show no influence on the enzymatic degradation. By measuring the affinity of alpha-amylase, beta-amylase and isoamylase for native, extruded non-modified and hydroxypropyltrimethylammonium-modified starches. It was evident that the enzymes' affinity for the substrate diminishes with increasing chemical modification, particularly in the case of alpha-amylase, suggesting that the location of cationic groups impairs the enzyme's recognition of the substrate. Structural elements of limit dextrins were analysed by (1)H NMR.