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Shakeel Ahmed

Publications and source records attributed to Shakeel Ahmed.

15 recordsLinked to original sources
PubMed2006

Autozygosity mapping of Bardet-Biedl syndrome to 12q21.2 and confirmation of FLJ23560 as BBS10.

Bardet-Biedl syndrome (BBS) is a genetically heterogeneous autosomal recessive disorder characterized by variable obesity, pigmentary retinopathy, polydactyly, mental retardation, hypogonadism and renal failure. In order to identify novel BBS loci we undertook autozygosity mapping studies using high-density SNP microarrays in consanguineous kindreds. We mapped a BBS locus to a 10.1 Mb region at 12q15-q21.2 in a large Omani BBS family (peak lod score 8.3 at theta = 0.0 for marker D12S1722) that contained the recently described BBS10 locus. Mutation analysis of candidate genes within the target interval, including the BBS10 gene, revealed a homozygous frameshift mutation in FLJ23560 and mutations were also detected in four smaller consanguineous families with regions of autozygosity at 12q21.2. These findings (a) confirm a previous report that FLJ23560 (BBS10) mutations are a significant cause of BBS, and (b) further demonstrate the utility of high-density SNP array mapping in consanguineous families for the mapping and identification of recessive disease genes.

Adult↗
PubMed2006

Intramedullary lipoma of the cervicodorsal spinal cord with intracranial extension: case report.

BACKGROUND: An unusual case of an extensive intramedullary lipoma of the cervicodorsal spinal cord with intracranial extension causing compression of spinal cord and brainstem is described. CASE DESCRIPTION: A 3-year-old child with lack of limb movement since birth, the cause of which had remained obscure, developed opisthotonos and episodes of severe respiratory difficulty with brief periods of apnea. Craniospinal computed tomography and magnetic resonance imaging (MRI) were diagnostic of lipoma. Urgent occipitocervical decompression and subtotal removal of the posterior fossa and cervical spinal cord lipoma resulted in lasting resolution of symptoms. CONCLUSIONS: Extensive spinal cord lipomas with intracranial extension can present with alarming spinal cord/medullary compression and respiratory symptoms. Computed tomographic scan and MRI are diagnostic. Total removal is not feasible, or necessary, because subtotal removal and decompression give long-lasting resolution of symptoms.

Brain Stem↗
PubMed2006

Guaianolides from Salvia nubicola (Lamiaceae).

A new sesquiterpene-lactone (nubenolide) belonging to the guaianolide class along with its acetate (nubenolide acetate) and a dimer (bisnubenolide) have been isolated from Salvia nubicola collected from Quetta, Pakistan. Structures of all three new metabolites were elucidated with the aid of spectroscopic techniques including 2D-NMR. However, the structure of nubenolide was finally confirmed via single-crystal X-ray diffraction method.

Cycloheptanes↗
PubMed2006

Hearing improvement after stapedotomy using teflon loop prosthesis.

OBJECTIVE: To assess hearing improvement after stapedotomy for otosclerosis using teflon loop prosthesis. DESIGN: Quasy experimental study. PLACE AND DURATION OF STUDY: January 2001 to May 2003 in the Otorhinolaryngology Department, CMH, Rawalpindi. PATIENTS AND METHODS: Thirty diagnosed cases of otosclerosis were included in the study. Ear with greater air-bone gap was selected and stapedotomy was done using teflon loop prosthesis (size 4 - 4.5 mm). Mild vertigo occurred during immediate postoperative period, which subsided with Inj. Prochlorperazine. Patients were followed-up postsurgically at one month, two months, four months, six months and one year and postoperative air-bone gap was calculated. RESULTS: Out of 30 cases, there were 24 males and 06 females. The age ranged from 18 to 50 years. Twenty-one (70%) patients had bilateral hearing loss and 09 (30%) had tinnitis also. Pre-operative audiograms showed conductive deafness. Carhart's notch was present in 10 (33.3%) cases. Tympanogram revealed loss of stapedial reflex. Postoperatively good hearing improvement was seen in 56.7% (postoperative air-bone gap closure upto 10 dB), fair improvement in 30% (postoperative air bone gap closure from 11 to 20 dB) and poor results in 10% (postoperative air-bone gap more than 21 dB) cases. One patient developed dead ear. CONCLUSION: Stapedotomy using teflon loop prosthesis for otosclerosis is an effective method to restore hearing. Complications are uncommon.

Adolescent↗
PubMed2005

Semen characteristics of the captive Indian white-backed vulture (Gyps bengalensis).

The present paper describes, to our knowledge for the first time, the successful collection and evaluation of semen from the Indian white-backed vulture (Gyps bengalensis), a critically endangered bird. Over a period of 2 yr, semen was collected using the manual massage method and evaluated for semen volume, semen pH, sperm concentration, percentage normal/abnormal spermatozoa, and percentage motile spermatozoa. It appears that the concentration of spermatozoa and percentage motile spermatozoa in the Indian white-backed vultures are low compared to those in other birds. Tyrode medium supplemented with albumin, lactate, and pyruvate (TALP) proved to be the best semen extender compared to two others (Beltsville Poultry Semen Extender and Lake diluent). Furthermore, TALP with 20% egg yolk and supplemented with 8% dimethyl sulfoxide maintained 50% of the initial percentage of motile spermatozoa following cryopreservation and thawing. A computer-aided semen analysis indicated that the spermatozoa of the Indian white-backed vulture are extremely active and swim in linear trajectories for up to 5 h following dilution in TALP. The trajectories were linear with time, but we noticed a decrease in the velocity parameters (average path velocity, curvilinear velocity, and progressive velocity). Thus, the present study provides baseline data on semen characteristics of the highly endangered Indian white-backed vulture, and these data could be of immense importance to reproductive and conservation biologists attempting to breed these animals in captivity, which to date has not been achieved.

Animals↗
PubMed2005

Evaluation of Alstonia scholaris leaves for broncho-vasodilatory activity.

The present study demonstrates that the ethanol extract of Alstonia scholaris (Apocynaceae) leaves induced pronounced bronchodilatory activity in anaesthetized rats with the probable involvement of prostaglandins. However, in vitro preparations of guinea-pig trachea did not confirm this property, indicating that bronchodilation is not due to the direct tracheal smooth muscle relaxation. The vasodilatory activity of the extract was independent of adrenergic or muscarinic receptors or prostaglandins but was mainly via endothelial-derived relaxing factor, nitric oxide. The extract inhibited the spontaneous movements of rabbit jejunum and contractile effects of acetylcholine and histamine on guinea-pig ileum. Additionally, the extract caused marked reduction of barium chloride-, potassium chloride- and calcium chloride-induced contraction on guinea-pig ileum and pulmonary artery, implying a direct interference of plant extract with the influx of calcium ions into cells. However, the extract has no detectable effect on mobilization of intracellular calcium. These results coupled with the in vivo effects of ethanol extract reveal that the Alstonia scholaris leaves possess broncho-vasodilatory activity mediated presumably by prostaglandins, calcium antagonism and endothelium-derived relaxing factor(s).

Alstonia↗
PubMed2005

Characterization and bioscreening of a new triterpenoid and a flavanone isolated from Salvia nubicola.

A new epimeric lupane triterpenoid, 3alpha-hydroxy-20-oxo-30-norlupane (1), and a new flavanone (nubatin; 3) have been isolated from Salvia nubicola collected from Quetta, Pakistan. The structures of these constituents were elucidated with the aid of spectroscopic techniques, including two-dimensional NMR and NOE experiments. Both the metabolites were found to be moderately bio-active.

Anti-Bacterial Agents↗
PubMed2005

Acute myocardial infarction in a patient with dextrocardia and situs inversus.

We report a case of 54-year-old man who presented to hospital with severe prolonged retrosternal chest pain of anginal nature. Electrocardiogram taken by his general practitioner showed minimal ST elevation in chest leads V1 and V2; there was also marked right axis deviation of P wave (negative in lead I and aVL) and of QRS complexes, together with low voltage in precordial leads V4 through V6 suggestive of dextrocardia. Repeat electrocardiogram with chest and limb leads reversed showed widespread, significant ST elevation in lead I, aVL, and V1 through V5 in keeping with extensive acute anterior myocardial infarction (MI). High cardiac enzymes and troponin level provided further confirmation. The extent of MI in such patients may be underestimated unless dextrocardia is timely recognized and leads reversed. We recommend that for patients with dextrocardia and situs inversus presenting with MI, both chest and limb leads be reversed to reveal the true extent of the infracted area.

Dextrocardia↗
PubMed2004

Diclofenac residues as the cause of vulture population decline in Pakistan.

The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent. A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India. Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent. Consequently these vultures are now listed as critically endangered by BirdLife International. In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh-Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites. Between 2000 and 2003, high annual adult and subadult mortality (5-86%) and resulting population declines (34-95%) (ref. 5 and M.G., manuscript in preparation) were associated with renal failure and visceral gout. Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure. Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock. We propose that residues of veterinary diclofenac are responsible for the OWBV decline.

Animals↗
PubMed2004

Genotypic analysis of Mycobacterium tuberculosis in Bangladesh and prevalence of the Beijing strain.

Genotypic analysis was performed on 48 Mycobacterium tuberculosis complex strains collected from a hospital in Dhaka city. Deletion analysis showed that the isolates were all M. tuberculosis; 13 of them were found to be of the "ancestral" type, while 35 were of the "modern" type, indicating that both endemic (ancestral type) and epidemic (modern type) strains cause tuberculosis in Bangladesh. Genotyping based on the spoligotype and variable-number tandem repeats (VNTR) of mycobacterial interspersed repetitive units (MIRU) was also done. A total of 34 strains (71%) were grouped by spoligotyping into nine different clusters; the largest comprised 15 isolates of the Beijing genotype, whereas the remaining eight clusters consisted of two to five isolates. MIRU-VNTR typing detected 32 different patterns among 44 tested strains, and the 15 Beijing strains were further discriminated by MIRU-VNTR typing (7 distinct patterns for the 15 isolates). These results indicate that MIRU-VNTR typing, along with spoligotyping and deletion analysis, can be used effectively for molecular epidemiological studies to determine ongoing transmission clusters; to our knowledge, this is the first report about the type of strains prevailing in Bangladesh.

Adult↗
PubMed2004

Management of oromandibular cancers.

OBJECTIVE: To emphasize the role and importance of multidisciplinary approach in the management of oral cavity cancers involving the mandible. DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: The Departments of Plastic and Reconstructive Surgery, ENT / Head and Neck Surgery and Radiation Oncology, Combined Military Hospital, Rawalpindi. Duration spans over a period of six years. SUBJECTS AND METHODS: A total of 63 patients who had biopsy-proven oromandibular tumors, after thorough assessment / staging in Joint Head and Neck Oncology Clinic, underwent resection and reconstruction for malignant oral cavity tumors involving the mandible were included in the study. All the resected tumor specimen were sent for histopathology. All the post-resection defects were properly classified and reconstructed by the plastic surgery team. Postoperatively, all the patients underwent adjuvant full dose radiotherapy at the Department of Radiation Oncology. Complications were recorded and managed accordingly. At one year follow-up all the available patients were assessed for functional and aesthetic restoration and recurrences. RESULTS: Out of 63 patients there were 40 males and 23 females (ratio 1.7 : 1) with an average age of 50 years. Tumor-free resection margins could be achieved in 56 patients. In 88% cases tumor was a Squamous cell carcinoma. Radical neck dissections were carried on in 27 patients. Radial forearm free flap was used in 27 patients, pectoralis major myocutaneous flap in 19, free fibula osteocutaneous flap in 10, rectus-abdominis myocutaneous free flap with Implant was used in 3 patients to reconstruct the post-resection defects. There was only one total flap loss and 3 partial flap losses. Implant exposure was encountered in 4 instances with 3 major and 5 minor fistulae. At one year follow-up, 56 patients were available. Thirty-seven patients had intelligible speech, 15 patients were taking normal diet and in 33 patients there was a satisfactory mandibular contour restoration. Seven patients had recurrences, 2 were not traceable and 5 patients had died by that time. CONCLUSION: A multidisciplinary collaboration is the key to effectively manage this group of extremely debilitating malignancies.

Adult↗
PubMed2004

Follicular carcinoma thyroid in Pendred syndrome.

Pendred syndrome is a rare inherited disorder of bilateral sensorineural deafness with goitre. Presence of follicular carcinoma thyroid makes it even rarer. A case of a young girl is described with the features of Pendred syndrome and euthyroid state. Follicular carcinoma of thyroid was detected on histopathology requiring re-tailoring of the management.

Adenocarcinoma, Follicular↗
PubMed2003

Rapid diagnosis of active tuberculosis by detecting antibodies from lymphocyte secretions.

In the present study, we investigated the tuberculosis (TB) diagnostic performance of an assay on the basis of detection of TB-specific antibodies from peripheral blood mononuclear cells (PBMCs), to determine whether antibodies in lymphocyte secretions obtained from PBMCs would better reflect active disease than antibodies in serum. PBMCs from patients with and without TB cultured in various concentrations for different times were assessed. Immunoglobulin G (IgG) specific for antigen (bacille Calmette-Guérin [BCG] vaccine and purified protein derivative [PPD]) was measured in lymphocyte secretions. Patients with active TB had higher BCG- or PPD-specific IgG antibody responses than patients without TB or healthy subjects (P=.001). This method can be used as a quick diagnostic aid to facilitate rapid detection of TB cases.

Acute Disease↗
PubMed2002

An unusual presentation of metabolic cardiomyopathy due to Pompe's disease.

An Omani infant boy who presented in the neonatal period with cardiac failure secondary to hypertrophic cardiomyopathy is reported. He subsequently progressed to show features of a metabolic disorder with multisystem involvement and was diagnosed to have Type II glycogenosis (Pompe's disease). The differential diagnosis and management of metabolic cardiomyopathy are outlined.

Cardiomyopathy, Hypertrophic↗