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31.
S. Ahmad V. Singh R.J. Sinha A. Srivastava A. Mandhani 《The African Journal of Urology》2018,24(4):255-263
Introduction
Renal cell carcinoma epitomizes a diversified group of tumors which contributes more than 15,000 deaths annually worldwide. In spite of tremendous efforts to identify prognostic factors apart from grade, histology and tumor size, they are not so obvious yet to fulfill the requirement. In this study, the prognostic role of serum matrix metalloproteinase (MMP)-2, 9, and vascular endothelial growth factor (VEGF) levels in patients with pre and postoperative renal cell carcinoma are evaluated to use as biomarker.Patients and methods
A total of 100 patients with a diagnosis of renal cell carcinoma included in the study. Additionally, hundred healthy kidney donors enrolled as control, serum MMP-2, MMP-9, and VEGF levels were analyzed in the serum of post and preoperative patients and parallel in control serum samples by ELISA method.Result
Most of the patients with RCC were found to have high concentrations of serum MMP-2, MMP-9, and VEGF. The levels of MMP-2 in the serum of preoperative patients ranged from 627 to 1117 ng/ml (833.90 ± 111.91), postoperative MMP-2 range 302–913 (553.02 ± 150.08), control range 122–384 (228.33 ± 72.52). In MMP-9 pre-operative range 619–1233 (862.32 ± 119.77), post-operative range 124–909 (552.88 ± 151.91) and control range 42–467 (245.44 ± 116.52 and in VEGF preoperative range was 0.792–2.214 (1.35 ± 0.36), postoperative range was 0.315–1.917 (0.81 ± 0.46) and in control it was 0.01–0.39 (0.10 ± 0.09). We observed that preoperative levels of all three markers, were significantly increased if compared with postoperative and control levels (P = 0.001) however, no any significant correlation found when the levels correlated with grade, stage, size, and type for MMP-2 and MMP-9, but VEGF shows some significance in comparison.Conclusion
The present data shows relevance and strong significant decrease in the level of MMP-2, MMP-9, and VEGF after surgery, so they could use as biomarkers in early disease diagnosis and also in monitoring disease recurrence. 相似文献32.
Maher El Chaar Jill Stoltzfus Maureen Melitics Leonardo Claros Ahmad Zeido 《Obesity surgery》2018,28(8):2233-2240
Introduction
The number of bariatric revisional cases has nearly doubled since 2011, and now comprises 13.6% of the total number of cases. The objective of this study is to evaluate the outcomes and safety of the two most common stapling revisional procedures, namely, sleeve and gastric bypass in comparison to primary stapling procedures using the MBSAQIP data registry.Methods
We reviewed all the sleeve and gastric bypass cases entered between January 1, 2015, and December 31, 2015, in the MBSAQIP data registry. We, then, identified sleeve and bypass patients who have had a previous bariatric procedure. Demographics and 30 day outcomes of all sleeve and gastric bypass patients were analyzed. We conducted within group comparisons comparing primary sleeve gastrectomy (PS) and primary gastric bypass (PB) patients to revisional sleeve (RS) and revisional gastric bypass (RB) patients, respectively. We, then, conducted group comparisons comparing RS to RB patients.Results
The total number of patients analyzed was 141,577 (98,292 or 69% sleeve patients and 43,285 or 31% gastric bypass patients). Among the sleeve patients, 92,666 (94%) had a PS and 5626 (6%) had RS. Among the bypass patients, 39,567 (91%) had a PB and 3718 patients (9%) had RB. 30-day readmission rate of RS was significantly higher as compared to PS (4.1 vs 0.4%, p?<?0.05). The incidence of at least one complication requiring reoperation or reintervention within 30 days following RS was twice as high as compared to PS (1.9 and 2% for RS vs 0.9 and 1.1% for PS respectively, p?<?0.05). Length of stay and 30 day mortality rates for PS and RS were the same. 30-day readmission rate of RB as compared to PB was 8.3 vs 6.3% (p?<?0.05). Also, the incidence of at least one complication requiring reoperation or reintervention following RB was 3.9 and 4%, respectively vs 2.4 and 2.7% for PB (p?<?0.05). In addition, readmission rates and unplanned admission rates to the ICU were significantly higher for RB compared to RS (8.3 and 2% for RB vs 4.1 and 0.9% for RS respectively, p?<?0.05). The incidence of at least one reoperation or one intervention following RB were also significantly higher compared to RS (3.9 vs 1.9% and 4 vs 2% respectively, p?<?0.05).Conclusion
Revisional stapling procedures are safe but the rates of complications following RS and RB are twice as high compared to PS and PB. Also, RB are more likely to develop complications compared to RS.33.
Christopher S. Ahmad 《Arthroscopy》2018,34(3):752-753
The optimal treatment of shoulder SLAP tears in high-level baseball players remains highly controversial. In pitchers, many SLAP lesions are found incidentally on magnetic resonance imaging and may in fact be adaptive to the baseball pitcher's mechanics of throwing. Surgical repair of SLAP lesions requires lengthy rehabilitation, and outcomes have been similar to or worse than the results after nonoperative treatment. The treatment option of biceps tenodesis is an appealing alternative to SLAP repair, but the indications and technique of biceps tenodesis in the elite pitcher still need to be defined. 相似文献
34.
A review of upper limb injuries in bear maul victims: Consistent pattern and inverse relation in severity with facial and scalp injuries 总被引:1,自引:0,他引:1
Towseef Ahmad Bhat Amara Gulzar Aejaz Ahmad Bhat Tariq Ahmad Bhat Zameer Ali 《中华创伤杂志(英文版)》2018,21(1):38-41
Purpose
Bear maul injuries are the most common wild animal inflicted injuries in India. More than 300 bear maul injuries report to our hospital per year.Methods
Twenty-one consecutive patients over a period of 1 year reported to our department for orthopaedic management of bear maul injuries. All the patients were referred either from peripheral hospitals or from other surgical departments of our hospital.Results
All the patients had facial/scalp injuries of variable severity. In all the patients the severity of limb and facial trauma was inversely proportional to each other. Pattern of upper limb trauma in most of the patients was similar. Fifteen patients had either fractures of distal humerus or mid shaft/proximal forearm bone fracture. Two had distal forearm bone fracture, 2 had carpal/metacarpal fractures and 1 had clavicle fracture. Only 1 had lower limb fracture. Thirteen out of 21 patients had associated neurovascular injury of the involved limb. The characteristic feature was extensive soft tissue involvement of the affected limb.Conclusion
Upper limb injuries in bear maul patients usually have similar pattern. The severity of upper limb and facial/scalp trauma is inversely proportional to each other. Multistage orthopaedic surgeries are needed for such complex limb injuries. 相似文献35.
AsmaGul Naz Muhammad Ali Muhammad Assad Aslam Abrar Ul Haq Khan Hamid Manzoor Rehana Iqbal Muhammad Ahmed Shehzad Shahbaz Ahmad Zubair Shaheen Sumaira Rasul 《Annals of human genetics》2019,83(6):426-433
Tuberculosis (TB) is a global issue as one‐third of the population worldwide is considered to be infected. TB has become a critical public health problem as a result of increasing drug resistance, which poses a challenge to current control strategies. Similar to environmental factors, genetic makeup of the host equally contributes to disease onset. We performed genotypic analysis to examine the relationship between IFNG and TB onset and drug resistance in a Pakistani population comprising 689 subjects. Notable differences were observed in the IFNG polymorphism (+874T/A) between the case and control groups. The frequency of the wild‐type genotype (TT) in the controls (43.2%) was significantly higher than in the cases (25.3%) (odds ratio [OR] = 0.77, p < 0.0001), while the mutant genotype frequency (AA) (38.57%) in the cases was significantly higher than in the controls (22.6%) (OR = 1.46, p < 0.0001). The heterozygous genotype frequency (TA) did not significantly differ between the control and case groups. Compared with the controls, the variant allele (A) was approximately twice as frequent in the cases. Females and older people have a higher chance of disease development. Finally, the IFNG (+874T/A) polymorphism was not associated with drug sensitivity or resistance. However, a genotypic polymorphism of IFNG (+874T/A) was significantly associated with susceptibility to TB, and the T allele conferred protection against TB. Additional studies involving larger cohorts are needed to further explore this relationship between genetics and disease vulnerability. 相似文献
36.
37.
Inhibitors of elastase stimulate murine B lymphocyte differentiation into IgG‐ and IgA‐producing cells 下载免费PDF全文
38.
Ahmad Chaddad Siham Sabri Tamim Niazi Bassam Abdulkarim 《Medical & biological engineering & computing》2018,56(12):2287-2300
We propose a multiscale texture features based on Laplacian-of Gaussian (LoG) filter to predict progression free (PFS) and overall survival (OS) in patients newly diagnosed with glioblastoma (GBM). Experiments use the extracted features derived from 40 patients of GBM with T1-weighted imaging (T1-WI) and Fluid-attenuated inversion recovery (FLAIR) images that were segmented manually into areas of active tumor, necrosis, and edema. Multiscale texture features were extracted locally from each of these areas of interest using a LoG filter and the relation between features to OS and PFS was investigated using univariate (i.e., Spearman’s rank correlation coefficient, log-rank test and Kaplan-Meier estimator) and multivariate analyses (i.e., Random Forest classifier). Three and seven features were statistically correlated with PFS and OS, respectively, with absolute correlation values between 0.32 and 0.36 and p?<?0.05. Three features derived from active tumor regions only were associated with OS (p?<?0.05) with hazard ratios (HR) of 2.9, 3, and 3.24, respectively. Combined features showed an AUC value of 85.37 and 85.54% for predicting the PFS and OS of GBM patients, respectively, using the random forest (RF) classifier. We presented a multiscale texture features to characterize the GBM regions and predict he PFS and OS. The efficiency achievable suggests that this technique can be developed into a GBM MR analysis system suitable for clinical use after a thorough validation involving more patients. 相似文献
39.
Jose M. Sanchez Bornot KongFatt Wong-Lin Alwani Liyana Ahmad Girijesh Prasad 《Brain topography》2018,31(6):895-916
The brain’s functional connectivity (FC) estimated at sensor level from electromagnetic (EEG/MEG) signals can provide quick and useful information towards understanding cognition and brain disorders. Volume conduction (VC) is a fundamental issue in FC analysis due to the effects of instantaneous correlations. FC methods based on the imaginary part of the coherence (iCOH) of any two signals are readily robust to VC effects, but neglecting the real part of the coherence leads to negligible FC when the processes are truly connected but with zero or π-phase (modulus 2π) interaction. We ameliorate this issue by proposing a novel method that implements an envelope of the imaginary coherence (EIC) to approximate the coherence estimate of supposedly active underlying sources. We compare EIC with state-of-the-art FC measures that included lagged coherence, iCOH, phase lag index (PLI) and weighted PLI (wPLI), using bivariate autoregressive and stochastic neural mass models. Additionally, we create realistic simulations where three and five regions were mapped on a template cortical surface and synthetic MEG signals were obtained after computing the electromagnetic leadfield. With this simulation and comparison study, we also demonstrate the feasibility of sensor FC analysis using receiver operating curve analysis whilst varying the signal’s noise level. However, these results should be interpreted with caution given the known limitations of the sensor-based FC approach. Overall, we found that EIC and iCOH demonstrate superior results with most accurate FC maps. As they complement each other in different scenarios, that will be important to study normal and diseased brain activity. 相似文献
40.
Faheem Ullah Fatima Javed M. B. H. Othman Abbas Khan Rukhsana Gul Zulkifli Ahmad 《Journal of biomaterials science. Polymer edition》2018,29(4):376-396
Addressing the functional biomaterials as next-generation therapeutics, chitosan and alginic acid were copolymerized in the form of chemically crosslinked interpenetrating networks (IPNs). The native hydrogel was functionalized via carbodiimide (EDC), catalyzed coupling of soft ligand (1,2-Ethylenediamine) and hard ligand (4-aminophenol) to replace –OH groups in alginic acid units for extended hydrogel- interfaces with the aqueous and sparingly soluble drug solutions. The chemical structure, Lower solution critical temperature (LCST ≈ 37.88 °C), particle size (Zh,app ≈ 150–200 nm), grain size (160–360 nm), surface roughness (85–250 nm), conductivity (37–74 mv) and zeta potential (16–32 mv) of native and functionalized hydrogel were investigated by using FT-IR, solid state-13C-NMR, TGA, DSC, FESEM, AFM and dynamic light scattering (DLS) measurements. The effective swelling, drug loading (47–78%) and drug release (53–86%) profiles were adjusted based on selective functionalization of hydrophobic IPNs due to electrostatic complexation and extended interactions of hydrophilic ligands with the aqueous and drug solutions. Drug release from the hydrogel matrices with diffusion coefficient n ≈ 0.7 was established by Non- Fickian diffusion mechanism. In vitro degradation trials of the hydrogel with a 20% loss of wet mass in simulated gastric fluid (SGF) and 38% loss of wet mass in simulated intestinal fluid (SIF), were investigated for 400 h through bulk erosion. Consequently, a slower rate of drug loading and release was observed for native hydrogel, due to stronger H-bonding, interlocking and entanglement within the IPNs, which was finely tuned and extended by the induced hydrophilic and functional ligands. In the light of induced hydrophilicity, such functional hydrogel could be highly attractive for extended release of sparingly soluble drugs. 相似文献