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Papers by Ali Haider

Cancers, 2021

Background: Primary skull base chondrosarcomas (SBCs) can severely affect patients’ quality of li... more Background: Primary skull base chondrosarcomas (SBCs) can severely affect patients’ quality of life. Surgical-resection and radiotherapy are feasible but may cause debilitating complications. We systematically reviewed the literature on primary SBCs. Methods: PubMed, EMBASE, Scopus, Web-of-Science, and Cochrane were searched following the PRISMA guidelines to include studies of patients with primary SBCs. Clinical characteristics, management strategies, and treatment outcomes were analyzed. Results: We included 33 studies comprising 1307 patients. Primary SBCs mostly involved the middle-fossa (72.7%), infiltrating the cavernous-sinus in 42.4% of patients. Cranial-neuropathies were reported in 810 patients (62%). Surgical-resection (93.3%) was preferred over biopsy (6.6%). The most frequent open surgical approaches were frontotemporal-orbitozygomatic (17.6%) and pterional (11.9%), and 111 patients (21.3%) underwent endoscopic-endonasal resection. Post-surgical cerebrospinal-fluid lea...

Density Functional Theory (DFT) simulations predicted the formation of an oxocarbenium ions in ac... more Density Functional Theory (DFT) simulations predicted the formation of an oxocarbenium ions in acid catalyzed ring-opening of saturated lactones such as γ-valerolactone(GVL). The ring-opening proceeds in two steps where oxocarbenium ion ring-opens to form a stable carbenium ion, which on subsequent hydrogen elimination from the neighboring carbon leads to the formation of alkenoic acid. In biomass derived partially saturated 2-pyrones such as 5,6 dihydro-4-hydroxy-6-methylpyran-2-one (5DHHMP) ring-opening and decarboxylation occurs readily via a retro-Dels-Alder (rDA) reaction. The role of solvent and substituents in stabilizing the respective transition states versus the reactant state was studied to develop an understanding on the reactivity of the partially saturated 2-pyrone molecule via rDA reaction. Experimentally, catalytic conversion of a 2-pyrone molecule, that can be derived via direct fermentation of biomass (sugarcane bagasse), was carried out to produce a high value chemical with 93% conversion at 473 K. In order to develop an integrated bio and chemo-catalytic process, the interaction of biogenic impurities such as amino acids and proteins on a heterogeneous catalyst surface was studied by DFT simulations. DFT study shows that methionine a sulfur containing amino acid binds through sulfur on the hydrogenation catalyst surfaces like Ru and Ni and may further decompose to SCH3 and elemental sulfur and hence deactivate the catalyst irreversibly.

produce high value chemicals Shelaka Gupta, Nishant Sinha and M. Ali Haider* Department of Chemic... more produce high value chemicals Shelaka Gupta, Nishant Sinha and M. Ali Haider* Department of Chemical Engineering, Indian Institute of Technology (IIT) Delhi; Hauz Khas Delhi-110016 (India) 2 Accelrys KK, Bangalore, India. *haider@iitd.ac.in, +91-011-2659-1016, +91-888271115

Anticancer Research, 2021

Background/Aim: Leptomeningeal disease (LMD) is a debilitating complication of advanced malignanc... more Background/Aim: Leptomeningeal disease (LMD) is a debilitating complication of advanced malignancies. Immunecheckpoint inhibitors (ICIs) may alter disease course. We analyzed the role and toxicity of ICIs in LMD. Materials and Methods: We systematically reviewed the literature reporting on outcome data of patients with LMD treated with ICIs. Results: We included 14 studies encompassing 61 patients. Lung-cancer (44.3%), breast-cancer (27.9%), and melanoma (23.0%) were the most frequent primary tumors. Median duration of ICItreatment was 7-months (range=0.5-58.0): pembrolizumab (49.2%), nivolumab (32.8%), ipilimumab (18.0%). Radiological responses included complete response (33.3%), partial response (12.5%), stable disease (33.3%), progressive disease (20.8%). Twenty-two patients developed ICI-related adverse-events, mild (100%) and/or severe (15.6%). Median progression-free and overall survival were 5.1 and 6.3 months, and 12-month survival was 32.1%. Survival correlated with ICI agents (p=0.042), but not with primary tumors (p=0.144). Patients receiving concurrent steroids showed worse survival (p=0.040). Conclusion: ICI therapy is well-tolerated in patients with LMD, but concurrent steroids may worsen survival. Leptomeningeal disease (LMD) occurs in 5-10% of oncological patients, most commonly from primary melanoma, lung, and breast neoplasms (1). LMD presents with new neurological impairments and focal/diffuse meningealenhancement at T1-contrast MRI, and is confirmed at cerebrospinal fluid (CSF) cytology (2). Available treatments include systemic/intrathecal chemotherapy, whole-brain/focal radiotherapy, and supportive-care; more recently, targetedtherapy and immunotherapy have been considered (3). The therapeutic goal remains palliation, with mean survival of 3-6 months (4, 5). The immune system plays a major role in shaping the systemic response in neuro-oncology (6). Cancerous cells may elude the immune response by expressing immunecheckpoint ligands, such as cytotoxic T-lymphocyteassociated antigen 4 (CTLA-4) and programmed deathligand 1 (PD-L1), which suppress T-cell activation and proliferation (7). Immune-checkpoint inhibitors (ICIs) are novel agents directed at inhibiting these signals, enhancing immune recognition of tumors and T-cell response. ICIs have proven effective in brain metastases from melanoma, lung, and breast cancers, and clinical interest is expanding toward LMD (7-11).

Neuro-Oncology, 2019

Regardless of subtype, diffuse gliomas of adulthood are characterized by inexorable progression t... more Regardless of subtype, diffuse gliomas of adulthood are characterized by inexorable progression through treatment. Cancer recurrence in the context of therapy is by no means unique to gliomas. For many tumors residing outside the central nervous system (CNS), tissue-based analyses are routinely employed to document the molecular and cellular features of disease recurrence. Such interventions are inconsistently applied for gliomas, however, and lack rigorous standardization when they are. While many of the reasons underlying these discrepancies reflect pragmatic realities inherent to CNS disease, the suboptimal employment of histological and molecular assessment at recurrence nevertheless represents a missed opportunity to proactively guide patient management and increase knowledge. Herein, we address this quandary by pairing a succinct description of the histological, biological, and molecular characteristics of recurrent glioma with recommendations for how to better standardize and...

Canadian journal of ophthalmology. Journal canadien d'ophtalmologie, 2018

Fig. 1-(a) Optos fundus image shows mild blurring of disc margins and dull macula. (b) Anterior s... more Fig. 1-(a) Optos fundus image shows mild blurring of disc margins and dull macula. (b) Anterior segment photograph shows fine endothelial dusting and presence of (pseudo) hypopyon.

Pakistan journal of medical sciences

To share our initial experience of patient undergoing anastomotic Urethroplasty and trial without... more To share our initial experience of patient undergoing anastomotic Urethroplasty and trial without catheter, without post Urethroplasty pericatheter urethrogram. Prospectively maintained records of all patients undergoing standard transecting anastomotic Urethroplasty by single surgeon (one of the authors) at The Kidney Centre PGTI Karachi, Pakistan and Lifecare Hospital Abu Dhabi UAE from September 2006 to December 2017 were reviewed. In all except two cases, supra pubic catheter was removed at 2 weeks and per urethral catheter by 4 to 5 weeks following which patients were assessed for TWOC without pericatheter urethrogram. Patients were further advised to follow up with Uroflowmetry (UFM) at one week, one month, three and 12 months. In our series, Qmax less than 15 ml/s on UFM were considered to have recurrence and these patients were subjected to ascending urethrogram after six weeks of procedure. There were 18 patients who underwent anastomotic Urethroplasty in bulbar urethra. Th...

Cureus, Jan 31, 2018

Background End-stage renal disease frequently leads to increased cardiovascular mortality. Cardio... more Background End-stage renal disease frequently leads to increased cardiovascular mortality. Cardiovascular autonomic neuropathy (CAN) may be predictive of cardiac arrhythmias and sudden cardiac death in patients with end-stage renal disease. Methods A total of 70 patients with end-stage renal disease were included in the study. The assessment of cardiac dysautonomia was based on the four standardized tests performed at the baseline and, again, at the end of the study. The criteria for CAN included at least two abnormal test results. Results Fifty of 70 patients completed the study and were followed-up after one year. Out of the 50 patients, 44 (88%) had CAN at baseline. Twelve (24%) patients died at the one-year follow-up. Sudden cardiac death was reported in seven out of 12 (58%) patients. All seven patients who died had high dysautonomia scores (three abnormal tests) at the baseline. There was a significantly higher percentage of patients with all four abnormal tests amongst patien...

The Pan African medical journal, 2018

Stigmatization, social exclusion and consequent banishment from the society makes transgender&#39... more Stigmatization, social exclusion and consequent banishment from the society makes transgender's life even tougher; isolating, pushing and forcing them into inappropriate conducts/habits like selling sex. This study investigates the association of social exclusion/victimization with high-risk behaviors among transgender community of Rawalpindi and Islamabad (Pakistan). Through a cross-sectional study design, a sample of 189 transgender community living in twin cities of Rawalpindi and Islamabad was selected using snowball sampling technique. A validated close ended questionnaire was used to estimate the high-risk behaviors. Multivariate logistic regression was used to explore the competing outcomes associated with suicidal risk, selling sex and substance abuse. Majority study participants 77.8% experienced physical attacks with institutional discrimination even higher (91.5%). Commercial sex work and drug abuse was reported in 39.2% and 37.6% respectively. The prevalence of suici...

Journal of pain and symptom management, Jan 10, 2018

Optimal benefits from Palliative Cancer Care (PC) are achieved when first consults (PC1) occur ea... more Optimal benefits from Palliative Cancer Care (PC) are achieved when first consults (PC1) occur early, in the outpatient setting. Late PC1, like those in the intensive care unit (ICU), limit these benefits. To determine the proportion of PC1 over time in the outpatient, ICU, and inpatient non-ICU settings. We also examined patients' baseline characteristics and the timing of PC access (from PC1 to death) by the setting of PC1. We retrospectively evaluated consecutive cancer patients' records at our cancer center to ascertain the annual number of PC1 and its distribution across settings (2011 to 2017). ICU PC1 (n=309) and a random sample of an equal number of outpatient and inpatient non-ICU PC1 were reviewed to retrieve patients' characteristics and death date. PC1 total annual number increased by 58% from 2011 (n= 2286) to 2017 (n= 3615). We found a significant decrease in the proportion of ICU PC1 (from 2.3% in 2011 to 1% in 2017, p<0.001). There were no significant ...

JAMA oncology, Jan 19, 2018

Dr Haider had full access to all of the data in the study and takes responsibility for the integr... more Dr Haider had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Cureus, Jan 11, 2018

Insular gliomas were previously considered inoperable lesions and were typically treated via biop... more Insular gliomas were previously considered inoperable lesions and were typically treated via biopsy, chemotherapy and/or radiation, if not observation alone. Stereotactic biopsies of low grade insular gliomas can underestimate tumor grade or fail to establish malignancy. Moreover, the survival advantages of maximal safe resection for insular lesions are increasingly being recognized. As such, early surgical resection is increasingly being performed. As with most lesions, a differential diagnosis exists for apparent insular gliomas, with definitive diagnosis generally obtained upon resection. We report an illuminating case that presented similarly to an insular glioma undergoing malignant transformation, but resolved spontaneously following a nondiagnostic biopsy. A 53-year-old female patient presented with aphasia and dizziness, followed by syncope and a 30-minute loss-of-consciousness. Imaging findings included a 12 mm region of contrast enhancement and central necrosis within a la...

Cureus, Jan 24, 2017

Cranial dural arteriovenous fistulae (dAVFs) are complex vascular lesions, rarely encountered wit... more Cranial dural arteriovenous fistulae (dAVFs) are complex vascular lesions, rarely encountered within the pediatric population. Endovascular embolization has revolutionized the management of these lesions and should be regarded as the first-line treatment for the majority of dAVFs; however, in a subset of particularly complicated lesions, traditional routes of access either do not exist or have been eliminated in the course of prior embolization attempts. We describe the case of an 11-year-old boy with a complicated torcular dAVF refractory to multiple attempts at standard endovascular treatment. He was cured after direct surgical puncture of the superior sagittal sinus to obtain vascular access for coil embolization of the venous sac. We review the technical aspects of this particular case while highlighting the anatomic features of those dAVFs that require nontraditional, surgical access for appropriate treatment. We also describe a simple algorithm, which may help in identifying t...

Journal of Neuropsychopharmacology & Mental Health, 2016

ABSTRACT Background and Purpose. Mexican Americans are more likely to be of low socioeconomic sta... more ABSTRACT Background and Purpose. Mexican Americans are more likely to be of low socioeconomic status, have lower education levels, and limited access to healthcare, factors that place them at risk for substance use and mental health disorders such as depression and/or anxiety. Mexican American men are more likely to have these co-occurring disorders than non-US born Mexican men and Mexican American women. This research aims to estimate the prevalence and describe the correlates of co-occurring substance use and mental health conditions among aging Mexican-American heroin injecting men. Methods. Data for the current analysis comes from a larger study of Mexican-American injection heroin users (N=227). For this paper, participants were categorized into co-occurring condition and non-co-occurring condition groups. This dependent variable was created using two mental health screeners (Center for Epidemiological Studies Depression Scale for depression and Perceived Stress Scale for anxiety) and self-reported use of illicit drugs in the previous 30 days (e.g., heroin, cocaine, crack, etc). Respondents who met the cutoff scores for either depression (CESD) or anxiety (PSS) and had used illicit drugs in the last 30 days were included in the co-occurring conditions group. Selected covariates associated with the dependent variable were examined using chi-squares. These covariates include years of incarceration, lifetime traumatic events and various sociodemographic variables. Results. Findings suggest that respondents with co-occurring conditions were more like to experience traumatic events than those respondents without co-occurring conditions. Statistically significant associations were found between illness or injury to a close family member (p<.001), death of partner, parent or child (p<.002), and experiencing a loss (p<.030) and co-occurring conditions. Additionally, findings revealed that respondents incarcerated for longer periods of time were significantly less likely to have co-occurring substance use and mental health conditions. Those who spent 5 years in prison (57%) were more likely to have co-occurring conditions than those who spent 5 to 10 years in prison (55%), and both of those groups would have an even greater risk of co-occurring conditions than those who spent 15 to 20 years in prison (18%). However, the decrease in likelihood of co-occurrence was not present for those respondents who spent 20 or more years incarcerated. Conclusion/Implications. These findings may be explained by the access to healthcare, social service and drug prevention programs, education, consistent meals, and exercise facilities that are available in prison. The majority of these respondents originate from impoverished communities where there is limited access to services that may provide a buffering effect from co-occurring conditions. However, there seems to be a point in their incarceration history where more time spent in prison does not provide a “protective” effect. Future research will further examine these relationships using multiple regression models.

Cureus, 2017

Cervical nerve root avulsion is a well-documented result of motor vehicle collision (MVC), especi... more Cervical nerve root avulsion is a well-documented result of motor vehicle collision (MVC), especially when occurring at high velocities. These avulsions are commonly traction injuries of nerve roots that may be accompanied by a tear in the meninges through the vertebral foramina with associated collections of cerebrospinal fluid (CSF), thereby resulting in a pseudomeningocele. We present a case of a 19-year-old male who experienced an MVC and was brought to the emergency department (ED) with right arm paralysis and other injuries. A neurological examination demonstrated intact sensation but 0/5 muscle strength in the right upper extremity. A magnetic resonance imaging (MRI) of the spinal cord demonstrated massive epidural hematomas extending the length of the cervical spine caudally from C2. An MRI of the right brachial plexus showed C3-C7 anterior horn cell edema and associated traumatic nerve root avulsion with pseudomeningoceles on the right from C5-C8. The development of spinal cord hematoma with these injuries has rarely been documented in the literature and the multiple level avulsion described here with extensive hematoma is a rare clinical presentation. A literature review was conducted to determine the diagnostic requirements, treatment strategies, and complications of such an injury. Our patient received conservative treatment of the right brachial plexus injury and was transferred to an inpatient rehabilitation facility 13 days later.

BMJ case reports, Jan 22, 2016

Vertebrobasilar stroke carries a high mortality rate and can have symptom patterns that are compl... more Vertebrobasilar stroke carries a high mortality rate and can have symptom patterns that are complex and difficult to diagnose. Isolated infarcts of the pons are uncommon and the neuro-ophthalmic presentation of pontine stroke can be quite variable. There is a paucity of cases in the literature documenting neuro-ophthalmic pathology as the sole or primary manifestation of pontine stroke. Here is presented the case of a unilateral internuclear ophthalmoplegia (INO) with concomitant skew deviation, contralesional exotropia and ipsiversive torsional nystagmus as the initial and only presenting feature of an isolated pontine stroke. This case illustrates the need to consider a cerebrovascular event early in the differential of a complex ocular motility disturbance not in keeping with specific cranial nerve palsy. It similarly highlights non-paralytic pontine exotropia and skew deviation as important causes of acute onset acquired strabismus, and transient torsional nystagmus as a rare bu...

Control Theory and Informatics, 2012

This paper presents a new design for a Multi-rotor Unmanned Air Vehicle (UAV). The design is base... more This paper presents a new design for a Multi-rotor Unmanned Air Vehicle (UAV). The design is based on the requirement of highly stable hover capability other than typical requirements of vertical takeoff and landing (VTOL), forward and sidewise motions etc. Initially a typical Tri-rotor hovercraft is selected for modeling and analysis. Then design modifications are done to improve the hover stability, with special emphasis on compensating air drag moments that exist at steady state hover. The modified structure is modeled and dynamic equations are derived for it. These equations are analyzed to verify that our structural modifications have the intended stability improvement effect during steady state hover.

Journal of Organometallic Chemistry, 2015

ABSTRACT We report on the synthesis and solid-state characterization of two sandwich-type heterop... more ABSTRACT We report on the synthesis and solid-state characterization of two sandwich-type heteropoloytungstates containing three cyclobutyltellurium(IV) units, [(C4H8TeIV)3(XIIIW9O33)2]12- (X = As, 1; Sb, 2). Polyanions 1 and 2 were prepared by reaction of cyclobutyltellurium(IV)diiodide (C4H8TeI2) and the trilacunary, lone-pair-containing POM precursors [XIIIW9O33]9- (X = As, Sb) in aqueous pH 7.5 medium, and isolated in good yield. The title polyanions crystallized as hydrated mixed cesium-ammonium-sodium salts, Cs8.5(NH4)2.75Na0.75[(C4H8Te)3As2W18O66]·30H2O (1a) and Cs1.5(NH4)10Na0.5[(C4H8Te)3Sb2W18O66]·23H2O (2a), which were characterized in the solid state by single-crystal XRD, solid-state 125Te NMR, IR, thermogravimetric and elemental analyses. Both 1a and 2a are quasi–isomorphous, crystallizing in the chiral monoclinic space group C2, with unit cell parameters a = 18.211(5) Ǻ, b = 17.647(4) Ǻ, c = 16.872(4) Ǻ, β = 107.482(13)° for 1a, and a = 18.1265(8) Ǻ, b = 17.447(7) Ǻ, c = 16.632(6) Ǻ, β = 106.328(2)° for 2a.

Clinical Endoscopy, 2013

Gastrointestinal (GI) endoscopy is an essential component in the diagnosis and treatment of GI di... more Gastrointestinal (GI) endoscopy is an essential component in the diagnosis and treatment of GI diseases. Being reusable devices, GI endoscopes inevitably encounter pathogens that may contaminate subsequent patients, especially those who are immunosuppressed due to age or concurrent disease. Although the estimated rate of transmission of infection via GI endoscopy is extremely low at 1 in 1.8 million procedures, 1-3 many flaws and deficiencies in endoscope reprocessing can result in microbial transmission. 4 Therefore, disinfection is an essential component of the reprocessing of endoscopes be