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Biomedical subjects

M S Khan

Publications and source records attributed to M S Khan.

At least 19 recordsLinked to original sources

Screening of free-living rhizospheric bacteria for their multiple plant growth promoting activities.

Plant growth promoting rhizobacteria (PGPR) are known to influence plant growth by various direct or indirect mechanisms. In search of efficient PGPR strains with multiple activities, a total of 72 bacterial isolates belonging to Azotobacter, fluorescent Pseudomonas, Mesorhizobium and Bacillus were isolated from different rhizospheric soil and plant root nodules in the vicinity of Aligarh. These test isolates were biochemically characterized. These isolates were screened in vitro for their plant growth promoting traits like production of indoleacetic acid (IAA), ammonia (NH(3)), hydrogen cyanide (HCN), siderophore, phosphate solubilization and antifungal activity. More than 80% of the isolates of Azotobacter, fluorescent Pseudomonas and Mesorhizobium ciceri produced IAA, whereas only 20% of Bacillus isolates was IAA producer. Solubilization of phosphate was commonly detected in the isolates of Bacillus (80%) followed by Azotobacter (74.47%), Pseudomonas (55.56%) and Mesorhizobium (16.67%). All test isolates could produce ammonia but none of the isolates hydrolyzed chitin. Siderophore production and antifungal activity of these isolates except Mesorhizobium were exhibited by 10-12.77% isolates. HCN production was more common trait of Pseudomonas (88.89%) and Bacillus (50%). On the basis of multiple plant growth promoting activities, eleven bacterial isolates (seven Azotobacter, three Pseudomonas and one Bacillus) were evaluated for their quantitative IAA production, and broad-spectrum (active against three test fungi) antifungal activity. Almost at all concentration of tryptophan (50-500 microg/ml), IAA production was highest in the Pseudomonas followed by Azotobacter and Bacillus isolates. Azotobacter isolates (AZT(3), AZT(13), AZT(23)), Pseudomonas (Ps(5)) and Bacillus (B(1)) showed broad-spectrum antifungal activity on Muller-Hinton medium against Aspergillus, one or more species of Fusarium and Rhizoctonia bataticola. Further evaluation of the isolates exhibiting multiple plant growth promoting (PGP) traits on soil-plant system is needed to uncover their efficacy as effective PGPR.

Ammonia↗

Current trends in the diagnosis and management of renal nutcracker syndrome: a review.

Nutcracker syndrome is caused by compression of the left renal vein between the aorta and the superior mesenteric artery where it passes in the fork formed at the bifurcation of these arteries. The phenomenon results in left renal venous hypertension. The syndrome is manifested by left flank and abdominal pain, with or without unilateral haematuria. Other common presentation is as "pelvic congestion syndrome" characterized by symptoms of dysmenorrhea, dyspareunia, post-coital ache, lower abdominal pain, dysuria, pelvic, vulvar, gluteal or thigh varices and emotional disturbances. Likewise compression of the left renal vein can cause left renal-to-gonadal vein reflux resulting in lower limb varices and varicoceles in males. Its diagnosis is based on history and physical examination, basic lab tests to exclude other causes of haematuria, cystoscopy and ureteroscopy to confirm unilateral haematuria and exclude other causes of this sinister symptom. Sequence of imaging has more or less been rationalised to USS with Doppler studies, CT or MR angiography and finally phlebography with renal vein and IVC manometery to confirm the diagnosis.

Algorithms↗

Laparoscopic pyeloplasty and pyelopyelostomy for ureteropelvic junction obstruction in a duplicated collecting system.

Ureteropelvic junction obstruction can be associated with renal anomalies. We present a case of symptomatic ureteropelvic junction obstruction associated with a duplicated collecting system that was successfully treated by laparoscopic pyeloplasty and concomitant pyelopyelostomy. The operative time was 210 minutes, and the blood loss was 20 mL. The inpatient stay was 4.5 days, and the patient returned to work after 28 days. Subsequent renograms confirmed improvement in renal function and resolution of obstruction. After 1 year, the patient remained asymptomatic. This is a feasible minimally invasive procedure for this condition that requires advanced reconstructive and intracorporeal suturing skills.

Adult↗

Transplantation of kidneys from deceased adult polycystic donors.

Renal transplantation is the best treatment for end-stage renal disease. The discrepancy between donor organ supply and demand continues to widen. Maximum efforts should be made to make use of donor kidneys and we suggest that polycystic kidneys can be suitable marginal donor organs. Five polycystic cadaveric donor kidneys were transplanted in four recipients at our institution between year 2000 and 2004. The donor kidneys were either of normal size or moderately enlarged (less than 15 x 10 cm). Donor ages were 24, 46 and 55 years. All donors had normal serum creatinine at the time of organ retrieval. Recipients gave informed consent to be transplanted with the polycystic kidneys. Three of four recipients had primary graft function. The patient with primary nonfunction required graft nephrectomy 8 weeks post-transplantation. One patient died due to cardiovascular causes with a functioning graft 18 months after transplantation. Two patients remain well, 26 and 58 months after transplantation, with normal graft function. Our experience and the limited evidence from the literature suggest that, with careful selection of both donor and recipient, transplantation of cadaveric polycystic donor kidneys should be considered given the current organ shortage.

Adult↗

Robotic technology in urology.

Urology has increasingly become a technology-driven specialty. The advent of robotic surgical systems in the past 10 years has led to urologists becoming the world leaders in the use of such technology. In this paper, we review the history and current status of robotic technology in urology. From the earliest uses of robots for transurethral resection of the prostate, to robotic devices for manipulating laparoscopes and to the current crop of master-slave devices for robotic-assisted laparoscopic surgery, the evolution of robotics in the urology operating theatre is presented. Future possibilities, including the prospects for nanotechnology in urology, are awaited.

Humans↗

Laparoscopic management of cryptorchidism in adults.

OBJECTIVES: Little is reported on the management of impalpable testis in adults. We present the impact of laparoscopy in this patient group. PATIENTS AND METHODS: Twelve adult patients have been referred to our centre over the last year, with impalpable testis. Pre-operative assessment was by either ultrasound or magnetic resonance imaging (MRI) or both. Quality of life and patient satisfaction were assessed by validated SF8 and client satisfaction (CSQ-8) questionnaires. Patients were also administered a self constructed questionnaire specifically looking at the impact of a laparoscopic service on their condition. RESULTS: The mean age was 29 yrs (range: 19-36). Two patients declined treatment. Of ten patients undergoing transperitoneal laparoscopy, five had intra-abdominal testes treated by laparoscopic orchidectomy (none malignant), two had the vas going into the deep ring and needed inguinal orchidectomy for an impalpable nubbin while in three cases there were blind ending vessels and vas. SF8 scores for physical HRQoL were unchanged but mental scores were significantly improved (p < 0.03). All patients were completely satisfied with a mean CSQ-8 score of 30.6 out of a possible 32. The majority of patients indicated that the availability of a laparoscopic service had prompted them to seek medical advice. CONCLUSIONS: Laparoscopic examination and orchidectomy is a safe and reliable procedure. Excellent patient satisfaction and quality of life are achievable. In particular mental health scores improve as previous uncertainty is removed. The advent of laparoscopy has encouraged adult patients to seek advice regarding a condition that has been present since childhood. We advocate the use of laparoscopy in evaluating and treating adult patients with maldescended testes.

Adult↗

Occurrence of yellow mosaic geminiviral disease on bitter gourd (Momordica charantia) and its impact on phytochemical contents.

Natural occurrence of yellow mosaic disease was observed on bitter gourd (Momordica charantia). Association of geminivirus with the disease was investigated through polymerase chain reaction using geminivirus-specific primers and Southern hybridization with a probe prepared from the cloned DNA of a known geminivirus. The fruits, leaves and stem of infected and healthy plants were studied for phytochemical composition. The amounts of protein were 49%, 50% and 66% higher, total carotenoids were 36%, 33% and 40% lower, vitamin C were 23%, 48% and 50% lower, total phenols were 28%, 31% and 43% lower, and antioxidant activity were 36%, 48% and 43% lower in the severely virus infected fruits, leaves and stem, respectively, as compared with healthy plants. The loss in the quantity of these phytochemicals was also observed even in mild infected plants, which further increased with the severity of the symptoms. Similarly, ethanol and 50% ethanol soluble extractive were also 25-43% lower in the fruits, leaves and stem of infected plants as compared with the healthy plants. A 45% and 54% lower caffeic acid, and 78% and 59% lower amounts of ferulic acid in the fruits and stem, respectively, and a 25% loss of gallic acid were noticed in the leaves of the severely infected plants.

Antioxidants↗

Eczema herpeticum: a case report.

Primary herpetic gingivostomatitis is a relatively common and well-recognized condition that the dental practitioner may encounter in clinical practice. A primary herpetic infection in a child with atopic dermatitis such as eczema, however, predisposes them to eczema herpeticum. This can be a severe and potentially life-threatening condition. This paper describes one such case, discusses the aetiology, presentation and management of this condition, and highlights the importance of early recognition by the clinician.

Diagnosis, Differential↗

Volvulus--a rare complication of ileal conduit.

Conduit volvulus is a very rare complication of ileal conduit. To date, only seven surgically confirmed cases have been reported. Conduit volvulus is a potentially reversible cause of renal impairment in patients with urinary diversion. The diagnosis depends on accurate radiological evaluation. The length of the bowel to construct the ileal conduit, closure of defects around the conduit and its mesentery and retroperitonealization of ureteroileal anastomosis are the determining factors for such a complication.

Aged↗

Eosinophilic cystitis and its management.

Eosinophilic cystitis (EC) is a rare clinicopathological condition characterized by transmural inflammation of the bladder predominantly with eosinophils, associated with fibrosis with or without muscle necrosis. The cause of EC remains unclear, although it has been associated with various aetiological factors, such as allergy, bladder tumour, bladder trauma, parasitic infections and chemotherapeutic agents. EC is, probably, caused by the antigen-antibody reaction. This leads to the production of various immunoglobulins, which, in turn, cause the activation of eosinophils and initiates the inflammatory process. The most common symptom complex consists of frequency, haematuria, dysuria and suprapubic pain. Cystoscopy and biopsy are the gold standard for diagnosis. Additional laboratory evidence supporting the diagnosis includes proteinuria, microscopic haematuria and peripheral eosinophilia, the last one occurring in few patients. There is no curative treatment for this condition. Current treatment modalities include transurethral resection of the bladder lesion along with non-specific medical therapy, such as non-steroidal anti-inflammatory agents or steroids. Because the lesion tends to recur in spite of the above therapy, long-term follow-up is mandatory.

Algorithms↗

Attitudes towards skills examinations for basic surgical trainees.

Objective measures of surgical skill and cognition are becoming available. A questionnaire study examining surgeons' beliefs towards a skills-based examination, current standards and possible benefits was devised. Three hundred pairs of standardised anonymous questionnaires were sent to consultants and their basic surgical trainees (BSTs) irrespective of surgical specialty. Responses were requested using a Likert scale (1-5, 3=neutral response). Two-hundred and two replies were received (including 54 pairs). BST experience ranged from 6 to 60 months (mean 24 months). When questioned regarding current training in basic surgical skills, only 34% believed that they were given adequate training at present. Sixty-four per cent of respondents believed the introduction of a skills examination would raise standards and 66% believed it necessary. Eighty-three per cent of respondents believed that they or their BST would practice these skills, if an examination were introduced and 85% wanted or would provide dedicated teaching time for this. However, 68% had no access to a dedicated skills facility, and uptake of these, where available, was variable. When questioned about their ability to perform the six appropriate tasks, there was a poor correlation of scoring between the groups. Consultants and their BSTs do not believe that they are given adequate training in basic skills. The introduction of an examination would lead to practice of these skills and is seen as a positive move.

Attitude of Health Personnel↗

Follow-up of polytetrafluoroethylene arteriovenous fistulae for haemodialysis.

The polytetrafluoroethylene (PTFE) arteriovenous fistula allows vascular access for haemodialysis where a primary fistula or brachio-basilic vein transposition is not possible. We report patency rates and complications associated with these prosthetic grafts. Fifty-nine upper limb PTFE grafts in 48 patients were evaluated with a mean follow-up of 19 months (range 2-54 months). Three grafts (5%) were never used. The primary patency rate at 6 weeks was 90%. Cumulative secondary patency rates were 66% at 6 months, 36% at 12 months, 17% at 18 months, 3% at 24 months and 2% at 30 months. None of the grafts had remained patent at 3 years. Forty-six percent of the grafts studied thrombosed at least once and 32% became infected. Although the initial primary patency rate achieved compares favourably with that reported for brachio-basilic transposition fistulae, this study confirms that the use of prosthetic material is associated with a poor overall patency rate and high risk of complications. All options using autologous vein should be exhausted before considering prosthetic material.

Adolescent↗

Long-term outcomes of brachiobasilic transposition fistula for haemodialysis.

OBJECTIVES: The transposed basilic vein to brachial artery arteriovenous fistula provides secondary vascular access for haemodialysis. The long-term results of such fistula are assessed in this retrospective series. MATERIAL AND METHODS: Over a 5-year period 75 brachiobasilic transposition fistulae were performed in 74 patients. There was a median follow up of 14 months. RESULTS: Primary patency was achieved in 69 (92%) of the fistulae, and secondary patency in 74 (99%) of the fistulae. Successful interventions included angioplasties in four, and saphenous vein interposition in one, whilst three patients had failed thrombectomies. Dialysis was performed using 69 (92%) of the fistulae while 6 (8%) were never used. Of the 75 fistulae 47 (63%) were patent at follow up. Cumulative secondary patency was 66% at 1 year, 52% at 2 years, and 43% at 3 years. Complications developed in 41 (55%), and included thrombosis, infection, stenosis, arm oedema, bleeding, steal syndrome and microaneurysm formation. CONCLUSIONS: Brachiobasilic transposition fistulae have good long-term patency rates. The complication rate, although high, is lower than that reported for PTFE grafts. Brachiobasilic fistulae should be used in preference to PTFE grafts for secondary access.

Adolescent↗

Circadian variation--increased morning incidence of acute myocardial infarction in patients with coronary artery disease.

OBJECTIVE: To examine whether a circadian variation exists in the onset of symptoms of Acute Myocardial Infarction (AMI) in patients with Coronary Artery Disease (CAD) and to review the characteristics of such variation. SETTING: Patients with AMI admitted to the coronary care units of two teaching hospitals in the city of Karachi, Dr. Ziauddin Medical University Hospital and National Institute of Cardiovascular Disease. METHOD: The study population included patients admitted to the coronary care unit. The diagnosis was based on the onset of AMI signs and symptoms and ECG changes. The inclusion criterion was an age less than 76 years. RESULTS: The incidence of Myocardial infarction assessed by the onset of clinical symptoms exhibited a marked circadian variation. Myocardial infarction occurred 2.8 times more frequently during morning hours (period of maximum incidence) as compared to evening (period of minimum incidence). CONCLUSION: This result extends previous observation of the circadian variation in the incidence of AMI onset. This study also helps in searching the potential triggers to physiological changes that may occur during morning hours. Design and timing of cardioprotective medication may play a crucial role in improving circadian variation and prevention of AMI.

Adult↗