Two-dimensional penta-like PdPSe with a puckered pentagonal structure: a first-principles study.

Low-symmetry penta-PdPSe (Pd4P4Se4) with intrinsic in-plane anisotropy was synthesized successfully [P. Li et al., Adv. Mater., 2021, 2102541]. Motivated by this experimental discovery, we investigate the structural, mechanical, electronic, optical and thermoelectric properties of PdPSe nanosheets via density functional theory calculations. The phonon dispersion, molecular dynamics simulation, and cohesive energy mechanical properties of the penta-PdPSe are verified to confirm its stability. The phonon spectrum represents a striking gap between the high-frequency and the low-frequency optical branches and an out-of-plane flexure mode with a quadratic dispersion in the long-wavelength limit. The Poisson's ratio indicates that penta-PdPSe is a brittle nanosheet. The penta-PdPSe is a semiconductor with an indirect bandgap of 1.40 (2.07) eV using the PBE functional (HSE06 hybrid functional). Optical properties simulation suggests that PdPSe is capable of absorbing a substantial range of visible to ultraviolet light. Band alignment analysis also reveals the compatibility of PdPSe for water splitting photocatalysis application. By combining the electrical and thermal transport properties of PdPSe, we show that a high power factor is achievable at room temperature, thus making PdPSe a candidate material for thermoelectric applications. Our findings reveal the strong potential of penta-PdPSe nanosheets for a wide array of applications, including optoelectronic, water splitting and thermoelectric device applications.

Ab initio prediction of semiconductivity in a novel two-dimensional Sb2X3 (X= S, Se, Te) monolayers with orthorhombic structure.

[Formula: see text] and [Formula: see text] are well-known layered bulk structures with weak van der Waals interactions. In this work we explore the atomic lattice, dynamical stability, electronic and optical properties of [Formula: see text], [Formula: see text] and [Formula: see text] monolayers using the density functional theory simulations. Molecular dynamics and phonon dispersion results show the desirable thermal and dynamical stability of studied nanosheets. On the basis of HSE06 and PBE/GGA functionals, we show that all the considered novel monolayers are semiconductors. Using the HSE06 functional the electronic bandgap of [Formula: see text], [Formula: see text] and [Formula: see text] monolayers are predicted to be 2.15, 1.35 and 1.37 eV, respectively. Optical simulations show that the first absorption coefficient peak for [Formula: see text], [Formula: see text] and [Formula: see text] monolayers along in-plane polarization is suitable for the absorption of the visible and IR range of light. Interestingly, optically anisotropic character along planar directions can be desirable for polarization-sensitive photodetectors. Furthermore, we systematically investigate the electrical transport properties with combined first-principles and Boltzmann transport theory calculations. At optimal doping concentration, we found the considerable larger power factor values of 2.69, 4.91, and 5.45 for hole-doped [Formula: see text], [Formula: see text], and [Formula: see text], respectively. This study highlights the bright prospect for the application of [Formula: see text], [Formula: see text] and [Formula: see text] nanosheets in novel electronic, optical and energy conversion systems.

Frequency of Intradialytic Complications in Patients of End-Stage Renal Disease on Maintenance Hemodialysis.

Introduction Hemodialysis is a vital management option for end-stage renal disease (ESRD) patients. With adequate hemodialysis, patients can have a good quality of life but complications do occur during the session, which can be minor to life-threatening. The objective of this study was to assess the frequency of acute complications during this procedure. Material and methods An observational, cross-sectional study was conducted at Jinnah Postgraduate Medical Centre, Karachi, Pakistan. Patient data were collected about access, comorbid conditions, frequency and duration of hemodialysis, and intradialytic complications. Those with acute kidney injury were excluded. Results There was a total of 94 patients, with a mean age of 45.51±13.29 years, of which 62 (66%) were males and 32 (34%) were females. Diabetes mellitus was the most common cause of ESRD (47.9%, n=45). Patients on twice and thrice-weekly sessions were 51 (54.3%) and 43 (45.7%), respectively. The most common complication was hypotension (28.7%), followed by hypertension (17%), and nausea/vomiting (11.7%). The arteriovenous fistula was the most common access used (75.5%, n=71). Most patients were found to be on hemodialysis for more than five years (51.1%, n=48). Conclusion Blood pressure changes are critical while performing hemodialysis, just like we found hypotension as the most common intradialytic complication in our results, followed by hypertension. Others were fever, muscle cramps, and nausea/vomiting. a prospective follow-up study shall be done to have comparative and long-term results related to the acute and chronic complications of dialysis.

Two-dimensional carbon nitride C6N nanosheet with egg-comb-like structure and electronic properties of a semimetal.

In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson's ratios along bothXandYdirection and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in theIRrange of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices.

Frequency of Risk Factors and Outcome of Hospital-Acquired Acute Kidney Injury.

OBJECTIVE: To determine the frequencies of risk factors and the ultimate outcomes of ccute kidney injury (AKI) among hospitalized patients. MATERIALS AND METHODOLOGY: This prospective, observational study was carried out from September 15, 2018, to March 14, 2019. All admitted patients, both male and female, with AKI, were included. Those with chronic kidney disease (CKD), small size echogenic kidneys (on ultrasonography, performed on admission), and recent history of urological intervention were excluded from the study. All patients were assessed for etiological factors (sepsis, gastroenteritis, surgical, and obstetrical) and outcome (improved, progression to CKD, or expired). RESULTS: Out of a total of 230, most patients were aged between 20-50 years with a mean age of 38.99 ± 7.61 years. Males were 144 (62.61%) and females were 86 (37.39%). About 78 (33.91%) patients were hypertensive while 65 (28.26%) were diabetic. The cause of hospital-acquired AKI was found to be sepsis in most (71.73%, n=165) of the cases, followed by gastroenteritis (10.00%, n=23), surgical (9.56%, n=22), and obstetric (8.69%, n=20) causes. When the outcome was assessed, 10 (4.35%) patients expired, 154 (66.96%) improved completely, while 66 (28.69%) progressed to CKD. CONCLUSION: This study has shown that sepsis is the most common cause of AKI in patients admitted to the hospital. So we recommend that proper steps should be taken to ensure adequate hospital care for avoiding such outcomes in hospitalized patients, and further decrease mortality.

Comparison of the Efficacy of Gabapentin Versus Levodopa-C for the Treatment of Restless Legs Syndrome in End-Stage Renal Disease on Hemodialysis Patients.

OBJECTIVE: We aimed to compare the efficacy of gabapentin and levodopa-c for the symptoms of restless leg syndrome in patients of end-stage renal disease (ESRD) undergoing maintenance hemodialysis therapy. METHODS:  In this observational, cross-sectional study, patients of ESRD on hemodialysis with restless leg syndrome were included after assessment of symptoms and quality of sleep before the treatment by completing two questionnaires: the International Restless Leg Syndrome Study Group (IRLSSG) questionnaire and the Pittsburgh Sleep Quality Index (PSQI) scale. They were randomly divided into two groups. One group was prescribed levodopa-c (110 mg) as a single dose two hours before bedtime for four weeks. The other group was given gabapentin (200 mg) after each hemodialysis session for four weeks. After the treatment, the patients completed the two questionnaires again: the IRLSSG questionnaire and the Pittsburgh Sleep Quality Index. RESULTS:  In our study, men were 14 (53.8%), and women were 12 (46.2%). Gabapentin was given to 14 (53.8%) patients, and 12 (46.2%) patients were prescribed levodopa-c. In the levodopa group, the average baseline IRLSS was 24.333 ± 7.936), and the mean baseline PSQI score was 13.583 ± 3.396. After treatment with levodopa for four weeks, the mean IRLSS was 8.666 ± 3.312, and the mean PSQI score was 4.666 ± 2.839; a P-value of 0.00001 was noted. While in the gabapentin group, the mean baseline IRLSS was 26.071 ± 7.936, and the mean baseline PSQI score was 14.857 ± 3.254. After treatment for four weeks with gabapentin, the mean IRLSS was 5.3571 ± 1.392, and the post-treatment average PSQI was 2.992 (SD: 0.916); a P-value of 0.00001 was noted. CONCLUSION:  Both levodopa and gabapentin effectively relieve symptoms of restless leg syndrome and improve the quality of sleep and life in ESRD patients undergoing hemodialysis.

Vitamin D Deficiency in End Stage Renal Disease Patients with Diabetes Mellitus Undergoing Hemodialysis.

OBJECTIVES: To assess the association of hypovitaminosis D with diabetes mellitus (DM) in patients with end stage renal disease (ESRD) undergoing hemodialysis. METHODOLOGY: This cross-sectional study was conducted at the Jinnah Postgraduate Medical Centre between July 2019 and February 2020. Patients with diagnosed ESRD who were on hemodialysis, with or without concomitant DM were registered. Vitamin D levels were categorized according to the severity of the deficiency or excess as 0-10 ng/mL, severely deficient; 11-20 ng/mL, deficient; 21-32 ng/mL; insufficient, 33-49 ng/mL, adequate; 50-65 ng/mL, optimum; and above that as high. Patients were stratified according to the status of DM.  Results: In a total of 80, the mean age was 45.21±12.67 years with 51 (63.75%) males and 29 (36.25%) females. A total of 36 (45%) CKD patients had concomitant diabetes. The median vitamin D levels were 20.25ng/mL. It was found that chronic kidney disease (CKD) patients with concomitant DM had significantly lower levels of vitamin D [15.19±6.83 vs. 30.28±14.22 (p<0.001)]. Out of the 12 patients with a severe deficiency, three-fourths of the population had DM as comorbidity, while in those with 'deficiency', 19 (67.9%) had DM. The majority of the patients without DM had adequate or optimum levels of serum 25-hydroxyvitamin D levels. CONCLUSION: Current study indicated that deficiency of serum vitamin D is associated with concomitant DM in patients with CKD as the majority had a severe deficiency of serum 25(OH)D. Supplemental vitamin D may help correct the deficiency and prevent the associated complications in patients.

Comparison between Angiographic Findings of Coronary Artery Disease in STEMI and NSTEMI Patients of Bangladesh.

Coronary Angiogram (CAG) has been used to detect coronary artery disease in myocardial infarction (both STEMI and NSTEMI) patients. The purpose of this study was to compare the degree of coronary artery disease among STEMI and NSTEMI patients. Among acute coronary syndrome in NSTEMI we found more widespread coronary artery disease other than STEMI. Lack of documentations encouraged us to perform this study in our center. In this retrospective observational study we summarized all myocardial infarction (MI) patients who underwent coronary angiography (CAG) from August 2013 to August 2014 at Enam Medical College Hospital, Dhaka, Bangladesh and data of degree of coronary artery disease were recorded. Data of 100 consecutive MI patients who underwent CAG during that period were recorded. Among them 50 patients having STEMI as Group I (male 45, female 5) & other 50 patients sustained NSTEMI as Group II (male 38, female 12). Among NSTEMI patient group 80% were having multi-vessel disease and in STEMI patient group 80% having single vessel disease and remaining having multi-vessel disease. The degree of coronary artery disease is extensive in NSTEMI patients than in STEMI group. Coronary angiogram can visualize the degree of coronary artery involvement and is a useful screening modality to compare disease extent in MI patients.

Patterns of Coronary Artery Anomalous Origin Reviewed by Coronary Angiogram in a Cardiac Center of Bangladesh.

Coronary Angiogarm (CAG) has been used to detect coronary artery anomalies. This cross sectional observational study aimed to assess the prevalence of anomalous origin of the coronary artery in the Bangladeshi patients. The researchers summarized responses of the target patients who underwent coronary angiography (CAG) from August 2010 to March 2011 in United Hospital Ltd., Gulshan, Dhaka, Bangladesh and data of anomalous origin of the coronary artery in Bangladeshi patients were recorded. Eighteen hundred (1800) patients underwent CAG during that period; 66 patients with an anomalous origin of the coronary artery were detected, giving a prevalence of 3.6%. The prevalence of anomalous origin of the coronary artery in Bangladeshi people in this study is 3.6%. CAG can visualize the anomalous origin of the coronary artery and is a useful screening modality.

Helicobacter pylori Infection and Inflammation: Implication for the Pathophysiology of Diabetes and Coronary Heart Disease in Asian Indians.

Asian Indians living in the Indian subcontinent or abroad experience high rate of coronary heart disease (CHD) and type 2 diabetes mellitus (T2DM). Asian Indians are also known to suffer from various infections, particularly during their childhood. One such chronic infection is with Helicobacter pylori (H. pylori). Since H. pylori with its specific virulence factor cytotoxin-associated gene A (cagA) has been suggested to be associated with CHD, a role of this H. pylori infection was investigated in the pathogenesis of CHD in Asian Indians living in Bangladesh. H. pylori (CagA) infected subjects with CHD (HP+ve cases, n=21), and without CHD (HP+ve controls, n=20), and non-infected without CHD (HP-ve normal controls, n=21) were included in this study. Thromboxane (TXB), an index of platelet activation, was found to be significantly higher in the HP+ve cases (p=0.05), but not in the HP+ve controls (p=0.88) when compared with HP-ve controls. Analyses of lipid profiles revealed that while triglycerides, total cholesterol and LDL did not show any significant changes, HDL was significantly lower in both the HP+ve cases (p=0.0003) and controls (p=0.005). The mean fasting glucose level in the HP+ve cases was markedly increased (p>0.0001), while it was intermediate in the HP+ve controls, and lowest in the HP-ve controls. HOMA-IR values, a measure of insulin resistance, did not reflect any substantial differences between the HP+ve and HP-ve controls, but they were highly significantly different between the HP+ve cases and HP-ve controls. HOMA-B, indicating insulin secretory dysfunction (ISD), was significantly higher in both the HP+ve groups when compared with the normal controls. The data indicate that H. pylori infection is associated with impaired insulin secretion, and that a component of insulin resistance that occurs independent of H. pylori can then lead to a worsening of glucose tolerance and the development of CHD. This is the first demonstration to our knowledge that H. pylori (CagA) infection is associated with insulin secretory dysfunction in human subjects. Since many Asian Indians contract various other chronic and acute infections, it is important to investigate the role of H. pylori and other infectious agents in the pathogenesis of T2DM and CHD.