Search PubMed⌕ Search

Biomedical subjects

G Singh

Publications and source records attributed to G Singh.

At least 55 records · Page 3Linked to original sources
PubMed2004

Calculus anuria in a spina bifida patient, who had solitary functioning kidney and recurrent renal calculi.

STUDY DESIGN: Clinical case report with comments by colleagues from Austria, Belgium, Germany, Japan, and Poland. OBJECTIVES: To discuss challenges in the management of spinal bifida patients, who have marked kyphoscoliosis and no vascular access. SETTING: Regional Spinal Injuries Centre, Southport, UK. METHODS: A female patient, who was born with spina bifida, paraplegia and solitary right kidney, had undergone ileal loop urinary diversion. Renal calculi were noted in 1986. Percutaneous nephrostolithotomy was performed in 1989 and there was no residual stone fragment. However, she developed recurrence of calculi in the lower pole of the right kidney in 1991. Intravenous urography, performed in 1995, revealed right staghorn calculus and hydronephrosis. Chest X-ray showed markedly restricted lung volume due to severe kyphoscoliosis. In 2000, she was declared unsuitable for anaesthesia due to a lack of venous access and a high likelihood of difficulty in weaning off the ventilator in the postoperative period. In June 2002, she developed anuria (urine output=18 ml/24 h) due to ball-valve-type obstruction by a renal stone at the ureteropelvic junction. Urea: 14.4 mmol/l; creatinine: 236 microl/l. Ultrasound showed right hydronephrosis. Percutaneous nephrostomy was performed. RESULTS: Following relief of urinary tract obstruction, there was postobstructive diuresis (3765 ml/24 h). However, the patient expired 19 days later due to progressive respiratory failure. CONCLUSION: In this spina bifida patient, who had reached the age of 35 years, severe kyphoscoliosis and lack of vascular access presented insurmountable challenges to implement the desired surgical procedure for removal of stones from a solitary kidney.

Adult↗
PubMed2004

Do spinal cord injury patients always get the best treatment for neuropathic bladder after discharge from regional spinal injuries centre?

OBJECTIVE: To draw attention to inadequate care received by some spinal cord injury patients after discharge from the regional spinal injury center. SETTING: Regional Spinal Injuries Centre, Southport, UK. METHODS: Presence of the urethral stricture was not recognised in a 69-year-old male with T-3 paraplegia, who attended a health-care facility with a urinary infection. A Foley catheter was inserted into the urethra only half-way and the catheter balloon was then inflated in the urethra distal to the stricture. In a 68-year-old male with T-8 paraplegia, a long-term indwelling catheter was eroding the urethra and he developed a severe degree of hypospadias while being managed in the community. A 49-year-old male with C-4 tetraplegia developed recurrent urine infections. He received several courses of antibiotics, which were prescribed by community health professionals. But he continued to be unwell. Subsequently, the patient was admitted to a district general hospital, where he was diagnosed to have mild chest infection and was about to be sent home. However, his wife was not happy, and then ultrasound of abdomen was taken, which revealed pyonephrosis. He was then transferred to a spinal unit. RESULTS: : These patients were not seen promptly in a regional spinal injury centre when they developed medical problems. The complications, which ensued, might have been prevented if expert medical treatment had been provided without delay. CONCLUSION: In order to meet the needs of a growing population of persons living in the community with spinal cord injury, more beds are required in spinal units. Provision of day surgery wards within spinal units, out-reach clinics and home visits by spinal cord clinicians may reduce the demand for admission in a spinal unit. Education of community health professionals on delayed complications of spinal cord injury, and good communication between spinal cord clinicians, patients, carers, and community health professionals by telephone, e-mail or conventional postal system are likely to improve the care of spinal cord injury patients after discharge from spinal injury centres. Spinal cord clinicians should adopt a patient-centred care instead of the traditional, paternalistic, doctor-centred care.

Aftercare↗
PubMed2004

Delayed complications of discontinuation of intrathecal baclofen therapy: resurgence of dyssynergic voiding, which triggered off autonomic dysreflexia and hydronephrosis.

STUDY DESIGN: Case report. OBJECTIVES: To report insidious development of autonomic dysreflexia and hydronephrosis due to dyssynergic voiding following discontinuation of intrathecal baclofen therapy. SETTING: Regional Spinal Injuries Centre, Southport, UK. METHODS: A male patient with paraplegia at T-5 (ASIA-A) had implantation of Medtronic Synchromed 8615 s programmable pump to control intractable spasms. After 4 years, the baclofen pump needed replacement because of battery exhaustion. At this time, he was taking oxybutynin 2.5 mg twice a day. He wore a penile sheath and performed intermittent catheterisation three times a day. Intravenous urography showed no dilatation of pelvicalyceal systems or ureters. During the course of the next 4 months, the dose of baclofen had to be increased gradually to 820 microg/day in order to control the spasms. Investigations revealed disconnection of the tube from the pump. The patient decided to undergo explantation of the pump and discontinue intrathecal baclofen therapy altogether. Following removal of the pump, he was prescribed baclofen 20 mg four times a day and diazepam 5 mg twice a day. He continued penile sheath drainage with oxybutynin 2.5 mg twice a day. Although spasms were controlled with oral baclofen and diazepam, he started getting transient, mild headache during reflex voiding. After nearly 2 years, he developed unbearable and pounding headache while passing urine. RESULTS: The dose of oxybutynin was increased to modified release formulation, 20 mg, once daily. He was prescribed modified release alfuzosin 10 mg once a day. Indwelling urethral catheter drainage was instituted. Intravenous urography showed dilation of left renal pelvis and calyces, and left ureter. After a fortnight, the dose of modified release oxybutynin was increased further to 25 mg once a day. After a month, he started performing self-catheterisation every 3 h and symptoms of autonomic dysreflexia subsided completely. A follow-up intravenous urography performed 6 months later, showed normal appearances of the left kidney. CONCLUSION: Spinal cord injury patients, in whom intrathecal baclofen therapy is terminated, need close monitoring of their urological status. Medications, which are prescribed for neuropathic bladder, and the method of bladder drainage, may need suitable changes, as discontinuation of intrathecal baclofen therapy can result in reappearance of detrusor-sphincter dyssynergia in previously susceptible patients.

Adolescent↗
PubMed2004

Combined gamma-irradiation and subsequent cisplatin treatment in human squamous carcinoma cell lines sensitive and resistant to cisplatin.

PURPOSE: To investigate the effects of combined radiation and subsequent cisplatin treatment on the human squamous carcinoma cell line SCC-25 and its cisplatin-resistant derivative SCC-25/CP. MATERIALS AND METHODS: SCC-25 and SCC-25/CP cells were treated with various gamma-ray doses (5 cGy-7 Gy) followed 60 min later by cisplatin treatment and subsequently assayed for survival using a conventional colony assay. For SCC-25, the subsequent cisplatin treatment was 0.1, 1, 10 and 20 microM for 1 h. For the more cisplatin-resistant SCC-25/CP cells, the subsequent cisplatin treatment was 10 and 50 microM for 1 h. RESULTS: The cisplatin-resistant SCC-25/CP cells were not cross-resistant to gamma-irradiation. Subsequent treatment with an LD50 concentration of cisplatin (10 and 50 microM for SCC-25 and SCC-25/CP, respectively) resulted in radiosensitization for SCC-25/CP but not for SCC-25 cells. Gamma-irradiation of SCC-25/CP cells followed by treatment with 10 and 50 microM cisplatin for 1 h resulted in radiation survival curves displaying a significant low-dose hypersensitive region followed by increased radioresistance at higher doses. A total of 10 microM cisplatin resulted in radiosensitization confined to the low-dose region (0.05 and 0.25 Gy), whereas the higher cisplatin treatment of 50 microM resulted in the appearance of a hypersensitive region together with a reduction of the increased radioresistance region. In contrast, cisplatin treatment (0.1, 1, 10 and 20 microM for 1 h) of SCC-25 cells had no significant effect on survival following 2.5 or 7.0 Gy and actually resulted in an increased low-dose radiation survival (0.05, 0.25 and 1 Gy) when survival was corrected for cisplatin treatment (p<0.01 for all cisplatin concentrations tested). CONCLUSIONS: The significant radiosensitization for SCC-25/CP given subsequent treatment with 50 microM cisplatin indicates cisplatin can inhibit the increased radioresistance response in SCC-25/CP cells. In contrast, the subsequent cisplatin treatment of SCC-25 cells can enhance their survival following low radiation doses.

Antineoplastic Agents↗
PubMed2004

Contrast-free unilateral endoscopic palliation in malignant hilar biliary obstruction: new method.

BACKGROUND: Bilateral endoscopic drainage is difficult in malignant hilar biliary obstruction. Recently, unilateral drainage in malignant hilar biliary obstruction has been shown to be equally effective. However, contrast injection leads to cholangitis. There have been no reported studies on contrast-free metal stenting in malignant hilar biliary obstruction. The present study was undertaken to evaluate the results of contrast-free unilateral metal stenting in type II malignant hilar biliary obstruction. METHODS: We prospectively studied the results of unilateral metal stenting in type II malignant hilar biliary obstruction without contrast injection in 18 patients. RESULTS: A successful endoscopic drainage was achieved in 100% (18/18) of patients with hilar strictures. Cholangitis and 30-day mortality occurred in none. CONCLUSIONS: Unilateral endoscopic metal stenting without contrast in type II malignant hilar biliary obstruction is a safe and effective method of palliation.

Biliary Tract Neoplasms↗
PubMed2004

The tensile properties of tension-free vaginal tape and cadaveric fascia lata in an in vivo rat model.

OBJECTIVE: To examine the tensile properties (break load and maximum average load), after in vivo implantation in a rat animal model, of tension-free vaginal tape (TVT) and cadaveric fascia lata (CFL), as pubovaginal slings of these materials have become popular for treating stress urinary incontinence. MATERIALS AND METHODS: Twenty Sprague-Dawley rats (300-400 g) had 1 x 2 cm strips of commercially available TVT and CFL implanted on the right and left anterior abdominal wall, respectively. Half of the animals were then killed at 6 weeks and the remainder at 12 weeks, after which the strips of TVT and CFL were removed and their tensile properties measured using a tensiometer. The tensile strength of TVT and CFL strips maintained only in normal saline served as controls. RESULTS: The TVT strips had a mean break load of 0.740 kg in the control and only 0.390 kg for CFL (P < 0.05). At 6 weeks the TVT material had a mean (sd) maximum average load of 0.634 (0.096) kg and a mean break load of 0.589 (0.249) kg, whereas the respective values for the CFL were 0.323 (0.198) and 0.167 (0.063) kg (P < 0.05). Similarly at 12 weeks, TVT had a greater mean maximum average and break load than CFL, at 0.742 (0.052) and 0.274 (0.126), and 0.737 (0.056) and 0.185 (0.128) kg, respectively. CONCLUSION: This is the first study to assess the tensile properties of the currently used sling materials, TVT and CFL, in an in vivo model. TVT has a greater break load and maximum average load than CFL; the tensile strength of these materials does not decrease with time.

Animals↗
PubMed2004

Cutaneous reactions in patients with solitary cysticercus granuloma on phenytoin sodium.

Several medical conditions are believed to be associated with an increased risk of cutaneous adverse reactions to anti-epileptic drugs. The aim of this study was to study the frequency and nature of cutaneous reactions in a cohort of patients being treated with phenytoin sodium for seizures, who were divided into those with a solitary cysticercus granuloma (SCG) and those with a condition other than SCG, to determine if the presence of SCG increases the risk of cutaneous adverse reaction to phenytoin. A cohort of 117, consecutively begun on treatment with phenytoin for seizure control, were followed up prospectively for the development of cutaneous reactions. There were 63 patients with SCG upon imaging and 54 patients to whom phenytoin was administered for seizures due to causes other than SCG or multiple neurocysticercosis. Cutaneous reactions were significantly more common (p = 0.02) in patients with SCG (9/63 patients; 14.3%) than in controls (2/54 patients; 3.7%). The spectrum of skin reactions in patients with SCG included benign skin rash (n = 3), anticonvulsant hypersensitivity syndrome (n = 4), Stevens-Johnson syndrome (n = 1), and urticaria (n = 1). Individuals with seizures due to SCG have a high incidence of cutaneous adverse reactions to phenytoin. This fact should be kept in mind when initiating them on treatment with this anti-epileptic drug.

Adult↗
PubMed2004

Familial risk of allergic rhinitis and atopic dermatitis among Chinese families in Singapore.

INTRODUCTION: This study aims to determine the familial risk of atopic dermatitis (AD) and allergic rhinitis (AR) in Chinese children. MATERIALS AND METHODS: A cross-sectional study was conducted in a housing estate in Singapore. Data was collected using an interviewer-administered questionnaire. Participants included 257 Chinese families. Prevalence rate ratios (PRRs) and 95% confidence interval (CI) were calculated. RESULTS: For AD in all children, an increasing trend was found with PRRs of 1.9 (95% CI, 0.3 to 11.8) and 1.5 (95% CI, 0.4 to 5.5) for only father and only mother affected, respectively, to 2.3 (95% CI, 0.4 to 13.7) for both parents affected. In AR, a PRR of 2.7 (95% CI, 1.8 to 3.9) and 2.2 (95% CI, 1.5 to 3.2) for only father and only mother affected, respectively, and 4.5 (95% CI, 3.3 to 6.1) for both affected was found. The PRR (2.2; 95% CI, 1.4 to 3.7) of the first child developing AR when paternal or maternal history was positive was similar. This rose to 3.4 (95% CI, 2.2 to 5.1) when both parents also had AR. The PRR of the second child developing AR was 3.9 (95% CI, 1.7 to 8.9) when the first child alone was positive for AR and 7.0 (95% CI, 3.5 to 13.9) when both parents and the eldest child had AR. CONCLUSION: A positive family history increases the risk of developing AD and AR with increasing risk dependent on number of relatives affected. The second child's risk of AR is also associated with AR in the first child, suggesting mechanisms of incomplete penetrance.

China↗
PubMed2004

Hallucinations in Parkinson's disease--a study of forty three patients.

OBJECTIVE: To see the prevalence of hallucinations in patients with Parkinson's disease and to compare the various parameters between hallucinators and non-hallucinators. METHODS: Forty-three patients of Parkinson's disease were included. Detailed motor assessment was done with UPDRS scales. Assessment was done for the presence of depression and sleep disturbances. The patients were enquired for the presence of depression and sleep disturbance. The patients were enquired for the presence of hallucinations. Hallucination types and associated emotional experience were probed into. Comparative analysis was subsequently done between hallucinators and non-hallucinators. RESULTS: The mean age of the patients was 61.47 years while mean duration of symptoms of PD was 4.30 years. The mean UPDRS II and III scores were 15.18 and 38, respectively. Fifteen patients (34.9%) had experienced hallucinations. The hallucinations described were visual as well as auditory in nature. Majority of these patients (12 out of 15, 80%) had not volunteered about their hallucinations on their own. On analysis of various parameters between the hallucinators and non-hallucinators, it was observed that hallucinators were older and had a higher mean duration of symptoms of PD. The patients with hallucinations had a higher severity of motor symptoms and signs. Hallucinators more commonly had depression and sleep disturbances. Mean dosage of L-dopa equivalent dose was higher in patients with hallucinations as compared to those without hallucinations. On statistical analysis, however, only two parameters were found to be different in a statistically significant manner. These were the duration of illness and the Hoen and Yahr scale (p < 0.05). Also, hallucinations occurred independent of dopaminergic drugs. CONCLUSION: Hallucinations are common source of distress but are often neglected. One should always probe actively into the presence of hallucinations.

Delusions↗
PubMed2003

Sodium channel inhibition by anandamide and synthetic cannabimimetics in brain.

Anandamide is a prominent member of the endocannabinoids, a group of diffusible lipid molecules which influences neuronal excitability. In this context, endocannabinoids are known to modulate certain presynaptic Ca(2+) and K(+) channels, either through cannabinoid (CB1) receptor stimulation and second messenger pathway activation or by direct action. We investigated the susceptibility of voltage-sensitive sodium channels to anandamide and other cannibimimetics using both biochemical and electrophysiological approaches. Here we report that anandamide, AM 404 and WIN 55,212-2 inhibit veratridine-dependent depolarization of synaptoneurosomes (IC(50)s, respectively 21.8, 9.3 and 21.1 microM) and veratridine-dependent release of L-glutamic acid and GABA from purified synaptosomes [IC(50)s: 5.1 microM (L-glu) and 16.5 microM (GABA) for anandamide; 1.6 microM (L-glu) and 3.3 microM (GABA) for AM 404, and 12.2 (L-glu) and 14.4 microM (GABA) for WIN 55,212-2]. The binding of [3H]batrachotoxinin A 20-alpha-benzoate to voltage-sensitive sodium channels was also inhibited by low to mid micromolar concentrations of anandamide, AM 404 and WIN 55,212-2. In addition, anandamide (10 microM), AM 404 (10 microM) and WIN 55,212-2 (1 microM) were found to markedly block TTX-sensitive sustained repetitive firing in cortical neurones without altering primary spikes, consistent with a state-dependent mechanism. None of the inhibitory effects we demonstrate on voltage-sensitive sodium channels are attenuated by the potent CB1 antagonist AM 251 (1-2 microM). Anandamide's action is reversible and its effects are enhanced by fatty acid amidohydrolase inhibition. We propose that voltage-sensitive sodium channels may participate in a novel signaling pathway involving anandamide. This mechanism has potential to depress synaptic transmission in brain by damping neuronal capacity to support action potentials and reducing evoked release of both excitatory and inhibitory transmitters.

Analysis of Variance↗
PubMed2003

Photodynamic therapy with photofrin in combination with Buthionine Sulfoximine (BSO) of human glioma in the nude rat.

High concentrations of cellular glutathione (GSH) within tumour cells may reduce the ability of photodynamic therapy (PDT) to selectively destroy tumour, consequently, a means of improving the therapeutic ratio of PDT in brain tumour is necessary. Therefore, we hypothesize that PDT in combination with Buthionine Sulfoximine (BSO), an agent which lowers cellular glutathione, can significantly enhance destruction of U87 and U251n tumour cells. PDT was performed using Photofrin as a photosensitiser in combination with BSO administration on male Fisher rats with intracerebral U87 and on non-tumour rats (administered at different optical doses in combination with Photofrin). In vitro experimentation utilising colony forming, cell cytotoxicity, and matrigel artificial basement membrane invasion assays showed significant enhancement of tumour kill and significant reduction of migration in tumour cells treated with BSO in combination with Photofrin PDT in comparison with individual therapies for both U87 and U251n cell lines. In vivo combination PDT-BSO treatment of U87 tumour rats exhibited significantly more tumour necrosis than individual treatments. In conclusion, our data suggests BSO enhances Photofrin PDT treatment of human glioma.

Animals↗
PubMed2003

Earlobe reconstruction using a Limberg flap in six ears.

Many methods of earlobe reconstruction using one or two stages have been described. These have used (i) the superimposition of two flaps, (ii) a single flap lined with a skin graft or (iii) doubled-over single or bilobed flaps. We present a new method of earlobe reconstruction using a doubled-over Limberg flap, which we have used in six ears. This produces a good-looking earlobe, which needs defatting after 3-4 months and suffered minimal necrosis at the tip of the folded flap in three cases. There was no earlobe shrinkage on long-term follow-up.

Adolescent↗
PubMed2003

Growth and mineral accumulation in Eucalyptus camaldulensis seedlings irrigated with mixed industrial effluents.

Effects of mixed industrial effluents on growth, dry matter accumulation and mineral nutrient in Eucalyptus camaldulensis seedlings were studied. The objective was to evaluate the adaptability of E. camaldulensis to effluent, tolerance to excess/deficiency of mineral elements and ultimately to determine suitable combinations of industrial/municipal effluent for their use in biomass production in dry areas. Different irrigation treatments were: T(1): good water; T(2): municipal effluent; T(3): textile effluent; T(4): steel effluent; T(5): textile effluent+municipal effluent in 1:1 ratio; T(6): steel effluent+municipal effluent in 1:2 ratio; T(7): steel+textile+municipal effluent in 1:2:2 ratio; and T(8): steel+textile effluent in 1:2 ratio. High concentrations of metal ions and low concentrations of Ca, Mg, K, Na, N and P in soil and seedlings of T(4) resulted in mortality of the seedlings within a few days. Addition of the textile/municipal effluent increased the survival time of the seedlings for two to three months in T(6), T(7) and T(8) treatments. Among the remaining treatments, the seedlings of T(2) attained 131 cm height, 1.97 cm collar diameter, 19 total branches and produced 158 g seedling(-1) of dry biomass at the age of 10 months. The seedling of T(3) produced the least growth and biomass. Growth equivalent to that of the seedlings of T(1) treatment was achieved when municipal effluent was mixed with textile effluent (T(5)). There was a decrease in soil pH, EC, SOC, NH(4)-N, NO(3)-N, PO(4)-P and basic cations and increase in the concentration of Cu, Fe, Mn and Zn with T(4) treatment. The reverse trend was observed in T(3) where a high concentration of Na might have reduced Mg and micronutrient concentration in seedlings potentially affecting root and leaf growth. Mixing of effluents may be useful in tree irrigation to increase biomass productivity, which is evidenced by improved growth in T(5) and survival in T(6), T(7) and T(8) treatments. Further, reduction of toxic concentration of metal ions in effluents may be helpful for a long-term field application.

Biomass↗