Publications by authors named "Khan Taqi"

38 Publications

Steroid-Sparing and Steroid-Based Immunosuppression in Kidney Transplant: Is There a Difference in Outcomes and Recipient Comorbidities?

Exp Clin Transplant 2020 10 6;18(5):572-576. Epub 2020 Jul 6.

>From the Department of Nephrology and Transplantation, King Salman Armed Forces Hospital, Tabuk, Saudi Arabia.

Objectives: Corticosteroids are fundamental to immunosuppression in kidney transplant but have significant side effects, generating interest in steroid-sparing immunosuppression regimens. We studied corticosteroid withdrawal on graft outcomes and comorbidities to study individualized approaches for immunosuppression. This is the first study of its kind in our ethnically distinct population.

Materials And Methods: Of 103 consecutive Saudi kidney transplant recipients seen in our unit during 2014-2018, 102 passed screening; 32 received no oral steroids after immunosuppression induction (steroid-spared group) and 70 received standard steroid-based immunosuppression. Both groups had similar immunosuppression induction: the standard steroid based immunosuppression included oral prednisolone (30 mg tapered to 5 mg over 6 wk), tacrolimus, and mycophenolate mofetil; however, the steroid-spared group did not receive corticosteroids after methylprednisolone induction. The Mann-Whitney U test compared numerical data, and the Fisher exact test compared categorical data. Relative risks for adverse events, graft dysfunction, and high serum creatinine were calculated. P < .05 was considered significant.

Results: Compared with the steroid-based group, patients in the steroid-spared group were older, had higher mean body mass index, and more favorable human leukocyte antigen matching and panel reactive antibody profiles. Mean serum creatinine and proportion of recipients with above normal serum creatinine were greater in the steroid-based group; this group also had slightly higher incidence of acute rejection. No graft failures or recipient deaths occurred in either group. The steroid-based group had significantly greater weight gain than the steroid-spared group (67% vs 34%; P = .002). The steroid-spared group exhibited better control of blood pressure and serum lipids; however, this was not statistically significant.

Conclusions: Early steroid withdrawal in selected transplant recipients is a viable option for immunosuppression, with no compromised graft function or survival shown in our cohort. Given the significant impact of weight gain, blood pressure, and serum lipids on recipient morbidity and mortality, a larger study is warranted.
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http://dx.doi.org/10.6002/ect.2020.0067DOI Listing
October 2020

Recipient Warm Ischemia and Delayed Graft Function.

Exp Clin Transplant 2020 02;18(1):136-138

From the Division of Transplant Surgery, Rehman Medical Institute, Hayatabad, Peshawar, Pakistan.

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http://dx.doi.org/10.6002/ect.2019.0317DOI Listing
February 2020

Prospective nonrandomized study with early steroid withdrawal (Day 5) postrenal transplant in low immunological risk patients: A singlecenter experience at prince sultan military medical city Riyadh.

Saudi J Kidney Dis Transpl 2019 Nov-Dec;30(6):1398-1406

Department of Nephrology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia.

Steroids remain an essential part of immunosuppressive therapy for renal transplant patients since the start of transplant era. Different immunosuppressive regimens are prescribed so as to minimize the side effects. The purpose of our study is to compare the outcome of early steroid withdrawal with steroid maintenance protocol. It is a prospective nonrandomized study. All patients that received renal transplants from January 2011 to December 2013 were included in the study. Early steroid withdrawal at day 5 was done in low immunological risk patients, and the results were compared with the steroid maintenance group, at one-year, posttransplant. Outcome measures included acute rejection (AR), slow graft function and delayed graft function (SGF and DGF), patient and graft survival, and new-onset diabetes after transplant (NODAT), dyslipidemia, hypertension, and obesity. A total of 249 patients were divided into two groups - 105 patients had early steroid withdrawal and 144 patients were maintained on steroid therapy. Outcome measures were compared one-year posttransplant. There was no significant difference in AR, patient and graft survival, creatinine level, and weight gain. However, a significant difference in systolic and diastolic blood pressure, lipid profile, NODAT, SGF, and DGF was found in the steroid group. Our study shows that early steroid withdrawal is a safe standard of care in low immunological risk patients.
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http://dx.doi.org/10.4103/1319-2442.275484DOI Listing
August 2020

Antithymocyte Globulin: Indiscriminate Use and Complications.

Ann Transplant 2019 11 22;24:605-607. Epub 2019 Nov 22.

Department of Nephrology and Transplantation, Rehman Medical Institute, Peshawar, Pakistan.

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http://dx.doi.org/10.12659/AOT.919655DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6886324PMC
November 2019

Implantation Warm Ischemia Time in Kidney Transplant Recipients: Defining Its Limits and Impact on Early Graft Function.

Ann Transplant 2019 Jul 23;24:432-438. Epub 2019 Jul 23.

Department of Nephrology and Transplantation, King Salman Armed Forces Hospital, Tabuk, Saudi Arabia.

BACKGROUND Prolonged cold ischemia is an established risk factor for poor early graft function (EGF). However, warm ischemia incurring during graft implantation has received little attention regarding its possible detrimental effect on EGF. The aim of our study was to examine the impact of recipient warm ischemia time on EGF. MATERIAL AND METHODS The data of 102 consecutive kidney transplants were analyzed to determine the association between duration of graft implantation time (IT) and EGF. Recipient IT groups were (GI) up to 45 min, (GII) 45-60 min, and (GIII) >60 min. EGF was categorized as immediate (IGF), slow (SGF), or delayed graft function (DGF). In recipients with IGF, graft function was further assessed by time needed for reduction in serum creatinine by 50% (SC50) of pre-transplant value, and serum creatinine on day 7 (SCD7). RESULTS Of a total of 102 recipients, 55 (55%) were in GI, 33 (32%) were in GII, and 14 (13%) were in GIII. Factors prolonging IT were recipient body mass index (BMI) (p=0.02) and multiple arteries in donor kidneys (p<0.01). No recipients in GI had DGF or SGF, while 2 in GII had DGF, and 5 patients in GIII had poor EGF. SC50 was significantly longer in GIII and GII versus GI (40.8±42.4 and 32.8±20.4 vs. 22.2±17.2 [p=.02, p≤.01]), respectively. Mean SCD7 was also significantly higher in GIII and GII versus GI. The mean last serum creatinine was comparable among all groups. CONCLUSIONS IT of more than 45 min was a risk factor for poor EGF, but achieved statistical significance only when it exceeded 60 min. Longer IT also significantly slowed the fall in SC50, and led to a higher SCD7. However, poor EGF and suboptimal early SC trends had little long-term effect on serum creatinine.
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http://dx.doi.org/10.12659/AOT.916012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6676983PMC
July 2019

Drug-Induced Hematological Cytopenia in Kidney Transplantation and the Challenges It Poses for Kidney Transplant Physicians.

J Transplant 2018 1;2018:9429265. Epub 2018 Aug 1.

RIPAS Hospital, Bandar Seri Begawan BA1710, Brunei Darussalam.

Drug-induced hematological cytopenia is common in kidney transplantation. Various cytopenia including leucopenia (neutropenia), thrombocytopenia, and anemia can occur in kidney transplant recipients. Persistent severe leucopenia or neutropenia can lead to opportunistic infections of various etiologies. On the contrary, reducing or stopping immunosuppressive medications in these events can provoke a rejection. Transplant clinicians are often faced with the delicate dilemma of balancing cytopenia and rejection from adjustments of immunosuppressive regimen. Differentials of drug-induced cytopenia are wide. Identification of culprit medication and subsequent modification is also challenging. In this review, we will discuss individual drug implicated in causing cytopenia and correlate it with corresponding literature evidence.
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http://dx.doi.org/10.1155/2018/9429265DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6093016PMC
August 2018

Pancreaticobiliary Maljunctions in European Patients with Bile Duct Cysts.

World J Surg 2018 11;42(11):3817-3818

King Salman Armed Forces Hospital, Tabuk, Saudi Arabia.

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http://dx.doi.org/10.1007/s00268-017-4455-zDOI Listing
November 2018

Implantation of Right Kidneys: Is the Risk of Technical Graft Loss Real?

World J Surg 2018 05;42(5):1536-1541

Institution Division of Nephrology, Prince Sultan Kidney Center, King Salman Armed Forces Hospital, Tabuk, Saudi Arabia.

Background: The left kidney (LK) is preferred by transplant surgeons, because its vein is always of good length and has a thick wall that enables safe suturing. On the other hand, the right renal vein is generally shorter and thinner walled, and well known for its technical difficulty during venous anastomosis, and can result in graft loss. We examined our living (LD) and deceased donor (DD) recipient data and compared the incidence of technical graft loss and early graft function in right and left kidneys.

Methods: A cohort of 58 adult and pediatric recipients received an LD or DD kidney between January 2015 and December 2016. The donor and recipient data were retrieved and retrospectively analyzed. Technical graft loss was defined as graft thrombosis within the 7 days after transplant.

Results: Right kidneys (RKs) were not a risk factor for technical graft loss, and no graft was lost for technical reasons in either LD or DD transplants. Early graft function in LK and RKs was also comparable in the LD cohort, and there were no LKs in the DD cohort.

Conclusion: Based on our data, the use of RKs was not a risk factor for technical graft loss and early graft function was comparable to LKs.
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http://dx.doi.org/10.1007/s00268-017-4314-yDOI Listing
May 2018

A Biophysical and Computational Study of Concanavalin A Immobilized Zinc Oxide Nanoparticles.

Protein Pept Lett 2018 Feb;24(12):1096-1104

Department of Biochemistry, Faculty of Life Sciences, AMU, Aligarh 202 002, India.

Background: Con A, a lectin extract from jackbean Canavalia ensiformis is known for its agglutination activity. ZnO nanoparticles promote the faster electron transfer between the lectin immobilized and the target cells. Hence, Con A immobilized on ZnO nanoparticles will agglutinate cells more effectively than the native protein.

Objectives: Concanavalin A (Con A), a lectin was immobilized on the hexagonal zinc oxide (ZnO) nanoparticles to monitor its activity on RBCs and lymphocytes.

Methods: The immobilization of Con A and zinc oxide nanoparticles has been studied by molecular docking, microscopic and genotoxicity assessment techniques.

Results: Qualitative assessment using various techniques like atomic force microscopy, scanning electron microscopy and X-ray diffraction showed minor changes in morphology of Con A and ZnO nanoparticles. FT-IR spectroscopy confirmed the linking of Con A amino groups with ZnO nanoparticles. Con A immobilized nanoparticles in contrast to native lectin showed minor changes in hemagglutination activity as confirmed by pH dependence studies using fluorimetry. Con Aimmobilized nanoparticles retained the agglutination activity, this can be indicative of their potential application in detection of virus transformed and neoplastic cells. The Con A immobilized ZnO nanoparticles did not induce any significant but minor damage to whole cell DNA as revealed from comet assay or plasmid DNA.

Conclusion: Con A immobilized on ZnO nanoparticles showed minor changes in the structure of ZnO nanoparticles and in the conformational of native Con A. However, Con A immobilized ZnO nanoparticles interestingly, showed pH resistance and better hemagglutination activity as well as minor DNA damage to whole cell lymphocytes. Thus, this novel bioaffinity support has prospective clinical implications.
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http://dx.doi.org/10.2174/0929866524666170920114057DOI Listing
February 2018

Dual Kidney Transplantation: A Review of Past and Prospect for Future.

Int Sch Res Notices 2017 2;2017:2693681. Epub 2017 Jul 2.

Aga Khan University Hospital, Karachi 74800, Pakistan.

Kidney transplantation (KT) is one of the treatment options for patients with chronic kidney disease. The number of patients waiting for kidney transplantation is growing day by day. Various strategies have been put in place to expand the donor pool. Extended criteria donors are now accepted more frequently. Increasing number of elderly donors with age > 60 years, history of diabetes or hypertension, and clinical proteinuria are accepted as donor. Dual kidney transplantation (DKT) is also more frequently done and experience with this technique is slowly building up. DKT not only helps to reduce the number of patients on waiting list but also limits unnecessary discard of viable organs. Surgical complications of DKT are comparable to single kidney transplantation (SKT). Patient and graft survivals are also promising. This review article provides a summary of evidence available in the literature.
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http://dx.doi.org/10.1155/2017/2693681DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5511653PMC
July 2017

Right Donor Kidneys in Living Donor Kidney Transplantation.

World J Surg 2017 11;41(11):2970-2971

King Salman Armed Forces Hospital, Tabuk, Saudi Arabia.

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http://dx.doi.org/10.1007/s00268-017-3940-8DOI Listing
November 2017

Galectins-A Potential Target for Cardiovascular Therapy.

Curr Vasc Pharmacol 2017 ;15(4):296-312

King Fahd Medical Research Center, King Abdulaziz University, P. O. Box 80216, Jeddah 21589. Saudi Arabia.

Cells constantly adapt to external humoral cues like cytokines and hormones, but practically most cellular behavior is under locally guided control via cell-cell interactions. Galectins (Gals) are one of the most prominent members of the group of molecules involved in this intercellular signaling. They are the family of β-galactoside specific lectins and consist of 15 different types, each with a specific function. They play crucial role in the immune system, inflammation, wound healing and carcinogenesis. In recent times, the role of Gals in the development of cardiovascular disease (CVD) has gained attention. Gals have been reported to act ambiguously by both relieving ischemia and accelerating atherosclerosis. Atherosclerosis can ultimately lead to myocardial infarction or ischemic stroke, which are both associated with Gals. There is also a role for Gals in the development of myocarditis by their influence on inflammatory processes. Moreover, Gal acts as a biomarker for the severity of myocardial ischemia and heart failure (HF). This review summarizes the association between Gals and the development and pathogenesis of CVD like atherosclerosis, stroke, myocardial infarction, and HF. A comprehensive outline of the association between Gals and more general mechanisms such as angiogenesis, arteriogenesis and atherosclerosis has also been provided. Modulation of Gal signaling holds great promise for the treatment of CVD as evident from preclinical studies.
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http://dx.doi.org/10.2174/1570161115666170201113046DOI Listing
April 2018

Is the Reluctance for the Implantation of Right Kidneys Justified?

World J Surg 2017 01;41(1):324-325

Department of Surgery, King Salman Armed Forces Hospital, Tabuk, Saudi Arabia.

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http://dx.doi.org/10.1007/s00268-016-3695-7DOI Listing
January 2017

Recent Updates on the Dynamic Association Between Oxidative Stress and Neurodegenerative Disorders.

CNS Neurol Disord Drug Targets 2016 ;15(3):310-20

King Fahd Medical Research Center, King Abdulaziz University, P. O. Box 80216, Jeddah 21589, Saudi Arabia.

Free radicals are generated as byproduct of our body metabolism, and their adverse effect on normal functioning of our body is prevented by body's own antioxidant machinery. Any perturbation in the defense mechanism of antioxidants inside body, its abnormal production or its induction from environment to our body lead to serious threats and is responsible for the development of various neurodegenerative disorders (NDDs). Perturbed antioxidants result in sensory and functional impairments in neuronal cells, which in turn cause NDDs. Free radical attack on neuronal cells plays a catastrophic role in NDDs. Impaired metabolism and generation of excessive reactive oxygen species also lead to a range of NDDs. Free radical induced toxicity is responsible for DNA injury, protein degradation, damage to tissue inflammation and cell death. Besides various genetic and environmental factors, free radical induced oxidative stress is also a major cause of NDDs. Application of upstream and downstream antioxidant therapy to counter oxidative stress can be an effective option in alteration of any neuronal impairment besides free radical scavenging. In the present manuscript, we have presented a comprehensive update on the symptoms, causes and cures of NDDs in relation with their dynamic association with oxidative stress.
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http://dx.doi.org/10.2174/1871527315666160202124518DOI Listing
December 2016

Protein misfolding and aggregation in Alzheimer's disease and type 2 diabetes mellitus.

CNS Neurol Disord Drug Targets 2014 ;13(7):1280-93

King Fahd Medical Research Center, King Abdulaziz University, P. O. Box 80216, Jeddah 21589, Kingdom of Saudi Arabia.

In general, proteins can only execute their various biological functions when they are appropriately folded. Their amino acid sequence encodes the relevant information required for correct three-dimensional folding, with or without the assistance of chaperones. The challenge associated with understanding protein folding is currently one of the most important aspects of the biological sciences. Misfolded protein intermediates form large polymers of unwanted aggregates and are involved in the pathogenesis of many human diseases, including Alzheimer's disease (AD) and Type 2 diabetes mellitus (T2DM). AD is one of the most prevalent neurological disorders and has worldwide impact; whereas T2DM is considered a metabolic disease that detrementally influences numerous organs, afflicts some 8% of the adult population, and shares many risk factors with AD. Research data indicates that there is a widespread conformational change in the proteins involved in AD and T2DM that form β-sheet like motifs. Although conformation of these β-sheets is common to many functional proteins, the transition from α-helix to β-sheet is a typical characteristic of amyloid deposits. Any abnormality in this transition results in protein aggregation and generation of insoluble fibrils. The abnormal and toxic proteins can interact with other native proteins and consequently catalyze their transition into the toxic state. Both AD and T2DM are prevalent in the aged population. AD is characterized by the accumulation of amyloid-β (Aβ) in brain, while T2DM is characterized by the deposition of islet amyloid polypeptide (IAPP, also known as amylin) within beta-cells of the pancreas. T2DM increases pathological angiogenesis and immature vascularisation. This also leads to chronic cerebral hypoperfusion, which results in dysfunction and degeneration of neuroglial cells. With an abundance of common mechanisms underpinning both disorders, a significant question that can be posed is whether T2DM leads to AD in aged individuals and the associations between other protein misfolding diseases.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5193501PMC
http://dx.doi.org/10.2174/1871527313666140917095514DOI Listing
July 2015

Acute appendicitis in kidney transplantation.

Authors:
Taqi T Khan

Ann Transplant 2014 Sep 3;19:434-5. Epub 2014 Sep 3.

Department of Kidney Transplant Surgery, Prince Salman Armed Forces Hospital, Tabuk City, Saudi Arabia.

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http://dx.doi.org/10.12659/AOT.891392DOI Listing
September 2014

Thymoglobulin induction in kidney transplantation.

Ann Transplant 2014 Aug 20;19:407-8. Epub 2014 Aug 20.

Department of Nephrology and Transplantation, Riyadh Military Hospital, Riyadh, Saudi Arabia.

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http://dx.doi.org/10.12659/AOT.892051DOI Listing
August 2014

Multiple renal arteries in living donor kidney transplantation: limits of recipient warm ischemia.

Saudi J Kidney Dis Transpl 2014 May;25(3):651-3

Kidney Transplant Surgery, Department of Nephrology and Transplantation, Prince Sultan Military Medical City, Riyadh, Saudi Arabia.

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http://dx.doi.org/10.4103/1319-2442.132225DOI Listing
May 2014

Recurrent Streptococcus bovis meningitis in Strongyloides stercoralis hyperinfection after kidney transplantation: the dilemma in a non-endemic area.

Am J Trop Med Hyg 2014 Feb 6;90(2):312-4. Epub 2014 Jan 6.

Institution Sections of Renal Transplant Surgery and Transplant Nephrology, Department of Nephrology and Transplantation, Division of Infectious Diseases and Histopathology, Departments of Medicine and Pathology, Riyadh Military Hospital, Riyadh 11159, Saudi Arabia.

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http://dx.doi.org/10.4269/ajtmh.13-0494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3919239PMC
February 2014

Is warm ischemia not a risk factor for delayed graft function in a living-donor kidney transplant?

Exp Clin Transplant 2013 Dec;11(6):573-4

Section of Kidney Transplant Surgery, Department of Nephrology and Transplantation, Riyadh Military Hospital, Riyadh, Saudi Arabia.

The association between prolonged donor warm ischemia time and poor early graft function has been challenged, but with little evidence. We intend to remove ambiguities and present evidence from the current literature. All donor surgeons must strive to limit warm ischemia to reduce poor early graft function and improve long-term outcomes.
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http://dx.doi.org/10.6002/ect.2013.0192DOI Listing
December 2013

ECD kidneys and re-transplantation.

Ann Transplant 2013 Dec 3;18:654-5. Epub 2013 Dec 3.

Kidney Transplant Surgery, Riyadh Military Hospital, Riyadh, Saudi Arabia.

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http://dx.doi.org/10.12659/aot.889782DOI Listing
December 2013

Redefining expanded criteria donor kidneys in the developing world.

Indian J Urol 2013 Oct;29(4):366-7

Sections of Kidney Transplant Surgery, Riyadh Military Hospital, PO Box 7897/624N - 11159 Riyadh, Saudi Arabia.

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http://dx.doi.org/10.4103/0970-1591.120136DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3822359PMC
October 2013

Motivation for living kidney donation in the developing world.

Ann Transplant 2013 Nov 12;18:609-10. Epub 2013 Nov 12.

Section of Kidney Transplant Surgery, Department of Nephrology and Transplantation, Riyadh Military Hospital, Riyadh, Saudi Arabia.

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http://dx.doi.org/10.12659/AOT.889667DOI Listing
November 2013

Detergent induces the formation of IgG aggregates: a multi-methodological approach.

Spectrochim Acta A Mol Biomol Spectrosc 2014 9;120:151-60. Epub 2013 Oct 9.

Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India. Electronic address:

Role of micellar environment created by Triton X-100 (TX-100) and CHAPSO on protein conformation using IgG as a model system has been studied in this paper. A substantial amount of secondary structure with the reduction in constant tertiary contacts was obtained in both bovine and human IgG in the presence of 0.12 mM TX-100 where as 6 and 8 mM CHAPSO concentration was required for this type of secondary structure. Further addition of either of the detergents result in the induction of α-helix in both the IgGs as evident by helix specific peaks in the amide I region of FTIR and circular dichroism spectra. Tryptophan and 8-anilino-1-naphthalene-sulphonic acid (ANS) fluorescence confirmed changes in protein conformation upon addition of detergents. Maximum ANS binding at 0.12 mM TX-100 in both while 6 and 8 mM CHAPSO in bovine and human IgG respectively, indicate a compact ''molten-globule''-like conformation. An increase addition of these detergents results in the burial of hydrophobic patches of both IgG owing to aggregation. Presence of aggregates at 0.2 and 0.16 mM TX-100 and 8 and 9 mM CHAPSO, for bovine and human IgG respectively, was further confirmed by reduction in ANS fluorescence, dynamic light scattering study, thioflavin T fluorescence and congo red absorbance.
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http://dx.doi.org/10.1016/j.saa.2013.09.141DOI Listing
September 2014

Molten globule of hemoglobin proceeds into aggregates and advanced glycated end products.

PLoS One 2013 26;8(8):e72075. Epub 2013 Aug 26.

Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India.

Conformational alterations of bovine hemoglobin (Hb) upon sequential addition of glyoxal over a range of 0-90% v/v were investigated. At 20% v/v glyoxal, molten globule (MG) state of Hb was observed by altered tryptophan fluorescence, high ANS binding, existence of intact heme, native-like secondary structure as depicted by far-UV circular dichroism (CD) and ATR-FTIR spectra as well as loss in tertiary structure as confirmed by near-UV CD spectra. In addition, size exclusion chromatography analysis depicted that MG state at 20% v/v glyoxal corresponded to expanded pre-dissociated dimers. Aggregates of Hb were detected at 70% v/v glyoxal. These aggregates of Hb had altered tryptophan environment, low ANS binding, exposed heme, increased β-sheet secondary structure, loss in tertiary structure, enhanced thioflavin T (ThT) fluorescence and red shifted Congo Red (CR) absorbance. On incubating Hb with 30% v/v glyoxal for 0-20 days, advanced glycation end products (AGEs) were detected on day 20. These AGEs were characterised by enhanced tryptophan fluorescence at 450 nm, exposure of heme, increase in intermolecular β-sheets, enhanced ThT fluorescence and red shift in CR absorbance. Comet assay revealed aggregates and AGEs to be genotoxic in nature. Scanning electron microscopy confirmed the amorphous structure of aggregates and branched fibrils of AGEs. The transformation of α-helix to β-sheet usually alters the normal protein to amyloidogenic resulting in a variety of protein conformational disorders such as diabetes, prion and Huntington's.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0072075PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3753358PMC
April 2014

Delayed graft function in living donor kidney transplantation.

Ann Transplant 2013 Aug 22;18:434-5. Epub 2013 Aug 22.

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http://dx.doi.org/10.12659/AOT.889487DOI Listing
August 2013

Glycation promotes the formation of genotoxic aggregates in glucose oxidase.

Amino Acids 2012 Sep 24;43(3):1311-22. Epub 2011 Dec 24.

Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India.

This study investigates the effect of pentose sugars (ribose and arabinose) on the structural and chemical modifications in glucose oxidase (GOD) as well as genotoxic potential of this modified form. An intermediate state of GOD was observed on day 12 of incubation having CD minima peaks at 222 and 208 nm, characteristic of α-helix and a few tertiary contacts with altered tryptophan environment and high ANS binding. All these features indicate the existence of molten globule state of the GOD with ribose and arabinose on day 12. GOD on day 15 of incubation forms β structures as revealed by CD and FTIR which may be due to its aggregation. Furthermore, GOD on day 15 showed a remarkable increase in Thioflavin T fluorescence at 485 nm. Comet assay of lymphocytes and plasmid nicking assay in presence of glycated GOD show DNA damage which confirmed the genotoxicity of advance glycated end products. Hence, our study suggests that glycated GOD results in the formation of aggregates and the advanced glycated end products, which are genotoxic in nature.
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http://dx.doi.org/10.1007/s00726-011-1204-8DOI Listing
September 2012

Antibody-mediated rejection: importance of lactate dehydrogenase and neutrophilia in early diagnosis.

Saudi J Kidney Dis Transpl 2011 May;22(3):525-30

Department of Renal Transplant Surgery, Riyadh Military Hospital, Riyadh, Saudi Arabia.

We report the importance of elevated serum lactate dehydrogenase (LDH) and neutrophilia (NT) in two renal transplant recipients who developed renal impairment in the early post-operative period. One of our recipients developed oliguria and increased serum creatinine with unexplained elevation of LDH and NT. The biopsy was C4d positive with platelet and fibrin thrombi in the glomerular capillaries and arterioles and interpreted as acute vasculitis or thrombotic form of antibody-mediated rejection (VAMR) with positive donor-specific antibodies (DSA). Despite intensive treatment, this graft was lost. When another patient developed a similar picture, prompt immunoadsorption was started without waiting for a confirmatory biopsy or DSA, and both were later reported as positive. Improvement in renal function was associated with decreasing levels of LDH and NT. Neither of these was elevated in cases of acute cellular rejection (ACR) or antibody mediated rejection (AMR) with isolated tubular injury (TAMR). It may therefore be reasonable to assume that LDH and NT are potential diagnostic and prognostic markers of VAMR.
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May 2011

Deceased donor kidney recovery procedure: Safe and simple in situ separation protects vascular anatomy.

Saudi J Kidney Dis Transpl 2011 Mar;22(2):341-4

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March 2011

A partially folded state of ovalbumin at low pH tends to aggregate.

Cell Biochem Biophys 2011 Jan;59(1):29-38

Department of Biochemistry, Faculty of Life Science, AMU, Aligarh 202 002, India.

At pH 2, ovalbumin retains native-like secondary structure as seen by far-UV CD and FTIR, but lacks well-defined tertiary structure as seen by the fluorescence and near-UV CD spectra. Addition of 20 mM Trifluoroacetic acid (TFA) or 30 mM Trichloroacetic acid (TCA) on acid-induced state results in protein aggregation. This aggregated state possesses extensive β-sheet structure as revealed by far-UV CD and FTIR spectroscopy. Furthermore, the aggregates exhibit decreased ANS fluorescence and increased thioflavin T fluorescence. The presence of aggregates was confirmed by size exclusion chromatography. Such a formation of β-sheet structure is found in the amyloid of a number of neurological diseases such as Alzheimer's and scrapie. Ovalbumin at low pH, in the presence of K(2)SO(4), exists in partially folded state characterized by native-like secondary structure and tertiary folds.
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http://dx.doi.org/10.1007/s12013-010-9108-xDOI Listing
January 2011