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Introduction/Aim: The Luminex assay, where beads are coated with a single HLA antigen, has been shown to detect HLA antibodies with more sensitivity and specificity as compared to microlymphocytotoxicity (CDC) assay and flow cross match (FCXM). We report the impact of low Mean Flourescence intensity (MFI) pre‐transplant DSA by Luminex with negative CDC and FCXM on acute rejection, graft function, and survival. Methods: In this retrospective study between January 2015 to December 2021, 45 recipients had pre‐transplant anti‐HLA donor‐specific antibodies (DSAs) detected by Luminex. Two control groups of 45 patients each matched for age and gender, first with non‐DSA HLA antibodies and second with no antibodies by Luminex were selected to compare outcomes with DSA group. Results: In the DSA group of 45, 22 (48.8%) had class I (MFI mean 4043 ± 1909, range: 1096–7111), 20 (44.4%) class II (MFI mean 3601 ± 2310, range: 1031–9259), and 3 (6.6%) both class I (MFI mean 4746 ± 1922) and class II (MFI mean 3940 ± 2312) antibodies. Acute rejection episodes were reported in 15.6%, DSA group, 17.8% in non‐DSA, and 24.4% in no antibody group (p =.538). Death censored graft survival at 1 and 5 years was 98% and 93% in DSA group, 100% and 95% in non‐DSA and 93% and 85% in the no antibody group (p =.254). Conclusions: Patients with low MFI DSA pre‐transplant, with a negative CDC and FCXM under ATG induction, have similar graft outcomes at 1 and 5 years when compared to non‐DSA and no antibody groups. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic Appendectomy (LA) is no longer a new procedure in pediatric surgery. In many pediatric surgery centers, laparoscopic management of acute appendicitis is practiced but we have observed that most of them performed laparoscopic appendectomy for simple straight forward appendicitis. It is generally considered that complicated appendicitis is better managed by an open procedure. The objective of this study was to establish safety of laparoscopic appendectomy in complicated appendicitis in children. Methods: Research was conducted at the Department of Pediatric Surgery, Shifa International Hospital Islamabad. Duration of study was 3 years after due approval from the ethical and research review board. Medical records of 42 patients who were operated on for complicated appendicitis laparoscopically at Shifa International Hospital, Islamabad from January 2018 to December 2020 was reviewed. All patients were enrolled from the emergency department. Clinical assessment of the patients was done in a routine way by history and physical examination. Investigations included complete blood count, C reactive protein and ultrasound abdomen and pelvis. Patients who had simple uncomplicated appendicitis, who had open appendectomy, and those who had laparotomy for other reasons were excluded from the study. All those patients who had complicated appendicitis like perforation, abscess, mass, or gangrene were included in the study. Variables observed in this study were age, gender, operative findings, operative time, hospital stay and postoperative complications. Results: The mean age of the patients was 9.95 ±3.22 years. Of 42 patients, 32 (76%) patients were male and 10 (24%) were female. Mean operative time was 42.5 ±20.03 minutes. Mean hospital stay was 2.23 ±1.55 days. Out of 42 patients, 20 (48%) had perforated appendicitis, 9 (21%) patients had appendicular mass, 12 (29%) patients had appendicular abscess, and 1 (2%) patient had gangrenous appendicitis. Postoperatively, one patient of perforated appendicitis had trocar site infection. One patient who had appendicular mass developed urinary retention with periorbital puffiness postoperatively. Two patients of appendicular mass had transaction of appendicular base due to perforated and sloughed appendicular base. One patient with an appendicular abscess had a large collection in the right paracolic gutter. One patient of appendicular abscess developed peritonitis with abscess formation secondary to cecal perforation. Conclusion: Laparoscopy for complicated appendicitis is safe in children with only fewer complications. Despite our limited experience of laparoscopic appendectomy, we believe that laparoscopy may safely be done as a first choice in all patients with appendicitis, whether simple or complicated. [ABSTRACT FROM AUTHOR]

Background: Foreign bodies in aero digestive tract is a common emergency in pediatric age group. Methods: This cross-sectional study included 156 patients of foreign bodies in aero digestive tract over a period of 2 years from January 2016 to December 2017. Results: Out of 156 patients, foreign body in esophagus was found in 111 patients with age range from 6 months to 12 years. Fifty-six patients (50%) belonged to 3-5 years age group. Coin was found in most of the patients which constitutes 61(55%) patients. Majority of the foreign bodies got impacted in cricopharynx. Of all the patients, 45 had foreign body in airway with age ranging from 6 months to 12 years. Peanuts were found in majority of cases, constituting 20% and right bronchus was mostly affected. One patient of foreign body ingestion expired. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to determine the frequency of in-hospital mortality in 351 patients who developed cardiogenic shock after acute myocardial infarction and by determining this; we might find that how efficiently we could manage this serious condition in our population by knowing the factors which are associated with high mortality after cardiogenic shock. Moreover impact of early revascularization like thrombolytic therapy or angioplasty was also evaluated. Results: Mean age was 65.41 ± 7.78 years in our study. In-hospital mortality with cardiogenic shock after acute myocardial infarction was found to be 44.73%. Significant association of in-hospital mortality was noted with age, hypertension, diabetes mellitus and BMI. Patients receiving early revascularization were noted to have lower in-hospital mortality compared to those in whom revascularization was not done due to delayed presentation. This study concluded that there is a high frequency (44.73%) of in-hospital mortality in patients with cardiogenic shock after acute myocardial in our population. So, we recommend that for achieving a good outcome and to reduce in-hospital mortality; in addition to rapid diagnosis of this condition, underlying risk factors like hypertension and diabetes should be evaluated and managed accordingly and early revascularization should be done when possible. [ABSTRACT FROM AUTHOR]

This deals with fabrication of macromolecular prodrugs (MPDs) of salicylic acid (SA) and aspirin (ASP) based on a hydrophilic cellulose ether, hydroxyethyl cellulose (HEC). Degrees of substitution (DS) of SA and ASP per HEC repeating unit (HEC-RU) were achieved ranging from 0.60 to 2.18 and 0.53 to1.50, respectively. The amphiphilic HEC-SA conjugate 2 assembled into nanowire-like structures, while HEC-ASP conjugate 6 formed nanoparticles (diameter 300–00 nm) at a water/DMSO interface. After oral administration in rabbit models, conjugates 2 and 6 showed plasma half-life of 6.96 and 7.01 h with maximum plasma concentration (C max ) of 15.27 and 23.01 μg L −1 , respectively, and each reached peak plasma concentration (t max ) at 4.0 h. Immunomodulatory assays (interleukin 6 and tumor necrosis factor-α values) revealed that anti-inflammatory properties of SA and ASP were unaltered in conjugates. Swelling inhibition of 61 and 71% was observed for conjugates 2 and 6, respectively, in a carrageenan induced paw edema test. Cytotoxic profiling (MTT assay) showed that conjugates were safe for administration in the concentration range of 2–10 mM up to 24 h. Thermal analyses revealed that Tdm values of SA and ASP conjugates were increased by 99 and 154 ̊C, respectively, indicating extraordinary thermal stability imparted to drugs after MPD formation. [ABSTRACT FROM AUTHOR]

Background Acute rejections ( ARs) with plasma cell-rich infiltrates ( PCARs) are associated with poor outcomes. Patients and methods Between February 2012 and December 2013, 1630 dysfunctional renal graft biopsies were performed. Of these, 50 (3%) showed PCAR. ARs with >10% plasma cells were defined as PCAR. Human leukocyte antigen ( HLA) antibodies were tested in historic sera and at the time of PCAR. Treatment for PCAR comprised methylprednisolone, antithymocyte globulin, plasmapheresis, and anti- CD20 antibody. Results Of the 1630 dysfunctional biopsies, 50 (3%) had PCAR which occurred 3.1 ± 2.55 yr after transplant. The percentage of plasma cells was 28.8 ± 11.7, and CD138, 29.0 ± 12.4. Donor-specific antibodies ( DSAs) were found in 32 (64%) overall, Class I in 15% and Class II in 65%. Post-treatment serum creatinine improved from 3.80 ± 2.59 to 2.66 ± 1.59 mg/dL in DSA positive (p < 0.003) and from 2.59 ± 1.09 to 2.08 ± 0.86 mg/dL in DSA negative (p < 0.008). One- and two-yr graft survival after PCAR was 72%, 42% in the DSA-positive vs. 89%, 82% in the DSA-negative group, respectively (p = 0.071). Conclusions Our results show that PCAR occurs late after transplant and in many cases is associated with DSAs. Graft outcome was poor when PCAR was associated with DSAs. [ABSTRACT FROM AUTHOR]

Rekindled interest has developed in pulsed vacuum systems due to their use for Xenon Difluoride (XeF 2 ) etching systems and their usefulness in the fabrication of MEMS and nanostructures. Despite numerous applications of pulsed vacuum systems, little information is available in the literature on their design considerations. In this paper mathematical models and their experimental verification are presented for various important design considerations of pulsed vacuum systems. Control of the chambers' pressures and pulse durations are typically the most important design considerations for processes involving pulsed vacuum systems. Pressure sensors give the exact pressure, but accurate chamber volumes are unknown. Thus a methodology is developed for accurate determination of chamber volumes that involves the introduction of a calibrated volume into a chamber. Then it is demonstrated that allowing a known pressure and volume of gas to move between two chambers leads to accurate temporal control of the chambers' pressures. Furthermore, by varying chambers' volumes, configurations, pressures, and the conductances between the chambers it is shown that the pulse duration could be accurately controlled. Though the model and demonstrations are presented in the context of a pulsed XeF 2 etching system, they are general and useful for all pulsed vacuum systems. [ABSTRACT FROM AUTHOR]

The design, fabrication and characterization of a recently developed test platform for the characterization of nanoscale properties of thin films are presented. Platforms are comprised of a microfabricated cascaded thermal actuator system and test specimen. The cascaded thermal actuator system is capable of providing tens of microns of displacement and tens of milli-Newton forces simultaneously while applying a relatively low temperature gradient across the test specimen. The dimensions of the platform make its use possible in both the scanning/transmission electron microscope environments and on a probe station under an optical microscope. Digital image correlation was used to obtain similar accuracy (~10 nm) for displacement measurements in both a SEM and under an optical microscope. Proof of concept experiments were performed on freestanding 250 nm thick Pt thin films. [ABSTRACT FROM AUTHOR]

A laboratory course on the theory, fabrication, and characterization of microelectromechanical systems (MEMS) devices for a multidisciplinary audience of graduate students at the University of New Mexico, Albuquerque, has been developed. Hands-on experience in the cleanroom has attracted graduate students from across the university's engineering and science campuses, including students from the Nano-Science and Micro Systems program, itself an interdisciplinary program. This course has been offered yearly for the last four years (since 2007) at the University of New Mexico. In one project from the class, a MEMS actuator is fabricated. This paper details the theory, fabrication steps, and characterization of a silicon-on-insulator (SOI) comb drive actuator that relies on fixed-fixed beams for its restoring force. Discussions include force generation by comb drives and a linear and nonlinear description of the restoring force applied by the fixed-fixed beams. Course assessment data is given from 79 students from three semesters, based on which the effectiveness of the laboratory project is evaluated. [ABSTRACT FROM PUBLISHER]

Climate change and rapid socioeconomic development have exacerbated the damage caused by hydrological droughts. To ensure effective drought defense and infrastructure development, it is essential to investigate variations in hydrological droughts. The primary objective of this study is to reconstruct the natural streamflow by using Soil and Water Assessment Tool (SWAT) hydrological modeling. The hydrological drought at different time scales (1, 3, 6, and 12 months) were measured using the streamflow drought index (SDI). The statistical parameters, including Nash–Sutcliffe Efficiency and the Coefficient of Determination, which yielded values of 0.84 and 0.82 during the calibration period and 0.78 and 0.76 during the validation period, respectively, showed a satisfactory SWAT model performance. Additionally, the Pettit test was used to identify a change point in streamflow within the 1991–2015 timeframe, leading to the division of the study period into two distinct phases: an undisturbed period (1991–1998) and a disturbed period (1999–2015). The SDI index‐based analysis revealed 9.39% moderate drought and 3.13% severe drought during the undisturbed period, while 11.76% moderate drought and 7.35% severe drought may happen due to the human influences that occurred in the disturbed period. These findings enhance the understanding of the hydrological drought variations in the Soan River basin for optimizing the water resources management system and effectively preventing and mitigating drought‐related damages. [ABSTRACT FROM AUTHOR]

Objective: Several biomarkers like NGAL, KIM-1, IL-18, and Cystatin C has been previously reported as reliable marker to predict AKI. However, their predictive accuracy varies widely. We aim to observe the efficacy of multiple markers, NGAL, KIM-1, Cystatin C and IL-18, in obstetric population who are at risk of developing AKI. Methods: This prospective study was carried out between June 2021 to March 2022 at Department of Obstetrics & Gynecology Unit II, Ruth Pfau KM Civil Hospital and Sindh Institute of Urology & Transplant (SIUT), Karachi Pakistan. On women brought to OBGYN-ER with the diagnosis of hemorrhage (antepartum and postpartum), hypertension (preeclampsia and eclampsia) and sepsis. The urine samples and 3cc blood was collected at the time of admission, blood sample processed for biochemistry at time of admission and repeat blood samples for serum creatinine at 24 and 48 hours. Urine was stored at -80ºC and later evaluated for NGAL, KIM-1, Cystatin C and IL-18. Serum Cystatin C was also processed for the time zero sample. The biomarkers were tested using ELISA assays. Results: A total of 149 women were included in the study, 83% of these women were non-booked. Twenty-six (17%) women developed AKI. Serum Cystatin C, urinary Cystatin C and urinary NGAL were found significantly raised in women who developed AKI. While KIM-1 and IL-18 were not raised to statistical significance in this population. However, urinary KIM-1 along with urinary Cystatin C were significantly raised in women with positive quick sequential organ failure assessment (qSOFA). Conclusion: This study validates the use of serum and urinary Cystatin C and urinary NGAL as highly predictable biomarkers for the development of AKI and nullifies urinary IL-18 and KIM-1 in this regard. [ABSTRACT FROM AUTHOR]

Naturally occurring hydrophilic polysaccharides are nowadays attracting the vigil eye of researchers working in areas of drug design and development. Amongst them, hydrophilic biopolymer hydroxypropylcellulose (HPC) is of particular interest. Its unique geometry allows the attachment of drug molecules with higher covalent loading as the hydroxyls are projected outside the polymer chains. The HPC-Ibuprofen conjugates as macromolecular prodrugs were therefore synthesized employing homogenous and one pot reaction methodology using p-toluenesulfonyl chloride. Present strategy appeared effective to synthesize conjugates with high yield (77-81%). Acid-base titration after saponification and 1H-NMR spectroscopic analyses have revealed high degree of drug substitution (DS 0.88-1.40) on to HPC. Uni-modal absorptions were observed in gel permeation chromatograms which indicated no significant degradation of polymer. Macromolecular prodrugs with different DS of ibuprofen were synthesized, purified, characterized and found soluble in organic solvents. From thermogravimetric analysis, initial, maximum and final degradation temperatures of the conjugates were calculated and compared for relative thermal stability. Thermal degradation kinetics was also studied and results have indicated that degradation of conjugates follows about first order kinetics as calculated by Kissinger model. The energy of activation was also found moderate 92.38, 99.34 and 87.34 kJ/mol as calculated using Friedman, Broido and Chang models. It was found that these novel prodrugs of ibuprofen were thermally stable therefore these may have potential pharmaceutical applications. [ABSTRACT FROM AUTHOR]

A technique based on suspended islands is described to measure the in-plane thermal conductivity of thin films and nano-structured materials, and is also employed for measurements of several samples with a single measurement platform. Using systematic steps for measurements, the characterization of the thermal resistances of a sample and its contacts are studied. The calibration of the contacts in this method is independent of the geometry, size, materials, and uniformity of contacts. To verify the technique, two different Si samples with different thicknesses and two samples of the same SiNx wafer are characterized on a single device. One of the Si samples is also characterized by another technique, which verifies the current results. Characterization of the two SiNx samples taken from the same wafer showed less than 1% difference in the measured thermal conductivities, indicating the precision of the method. Additionally, one of the SiNx samples is characterized and then demounted, remounted, and characterized for a second time. The comparison showed the change in the thermal resistance of the contact in multiple measurements could be as small as 0.2 K/μW, if a similar sample is used. [ABSTRACT FROM AUTHOR]

Background: Congenital epulis is a rare benign, smooth, sessile, or pedunculated, solitary mass of varying sizes commonly occurring at the anterior alveolar ridge of the maxilla. It can occur as a solitary as well as a multifocal lesion. Case Presentation: Case 1: A two-day-old female newborn presented with a single round, smooth, pedunculated mass measuring 3x2x2cm on the anterior alveolar ridge of the maxilla. Complete excision of the mass was done under general anesthesia. Histopathology confirms congenital epulis. No recurrence was found till one year of follow-up. Case 2: A one-day-old female newborn presented with a 3x4x3cm soft to firm mass arising from the right upper alveolar margin attached with a stalk and extending into the mouth without any respiratory difficulty. Complete excision of the mass was done under general anesthesia. Follow-up for one year showed no recurrence. Conclusion: Congenital epulis is a rare benign lesion most commonly arising from the anterior alveolar ridge of the maxilla without the involvement of bone or teeth. Complete surgical excision is the treatment of choice without any reported recurrence. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Living donor kidney is the main source of donor organs in low to middle income countries. We aimed to develop a living donor risk model that predicts graft and patient survival in an emerging economy. Methods: We used data from the Sindh Institute of Urology and Transplantation (SIUT) database (n = 2283 recipients and n = 2283 living kidney donors, transplanted between 1993 and 2009) and conducted Cox proportional hazard analyses to develop a composite score that predicts graft and patient survivals. Results: Donor factors age, creatinine clearance, nephron dose (estimated by donor/recipient body weight ratio) and human leukocyte antigen (HLA) match were included in the living donor risk model. The adjusted hazard ratios (HRs) for graft failures among those who received a kidney with living donor scores (reference to donor score of zero) of 1, 2, 3 and 4 were 1.14 (95%CI: 0.94–1.39), 1.24 (95%CI:1.03–1.49), 1.25 (95%CI:1.03–1.51) and 1.36 (95%CI:1.08–1.72) (P‐value for trend =0.05). Similar findings were observed for patient survival. Conclusions: Similar to findings in high income countries, our study suggests that donor characteristics such as age, nephron dose, creatinine clearance and HLA match are important factors that determine the long‐term patient and graft survival in low income countries. However, other crucial but undefined factors may play a role in determining the overall risk of graft failure and mortality in living kidney donor transplant recipients. [ABSTRACT FROM AUTHOR]