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Biomedical subjects

N Shah

Publications and source records attributed to N Shah.

At least 19 recordsLinked to original sources
PubMed2006

Anaemia in diabetic patients with chronic kidney disease--prevalence and predictors.

AIMS/HYPOTHESIS: We investigated the relationship between haemoglobin (Hb) and diabetes in patients with renal disease. SUBJECTS, MATERIALS AND METHODS: All adult patients with stable chronic kidney disease attending renal or diabetic outpatient clinics in a six-month period were identified. Patients' notes and electronic patient records were used to build a comprehensive biochemical and clinical database. Results were analysed for the predictors of Hb, the severity of anaemia in both groups and the relative impact of diabetes on haemoglobin and anaemia. RESULTS: The study group consisted of 468 patients, of whom 204 had diabetes and 264 did not. At every level of renal function haemoglobin levels were lower by an average of 10 g/l in subjects with diabetes than in those without. Likewise, anaemia was found to occur at an earlier stage of chronic kidney disease (and to be of greater severity) in diabetic patients. Independent predictors of haemoglobin included female sex, diabetes, renal function and serum albumin, with diabetes and renal function being the greatest predictors. Multiple logistic regression showed that patients with diabetes had an odds ratio of 4 for being anaemic. Had we used an estimated GFR of less than 60 ml/min to trigger investigation of anaemia, we would have detected 85% of anaemic patients. CONCLUSIONS/INTERPRETATION: Anaemia is frequently found in diabetic patients with renal disease, occurs earlier and is more severe than in similar but non-diabetic subjects. In contrast to previous publications, our findings suggest that anaemia is prevalent at the earliest stages of chronic kidney disease. We advocate an estimated GFR threshold of <60 ml/min to trigger investigation for anaemia in diabetic subjects.

Adult↗
PubMed2006

Routine coagulation screening in children undergoing gastrointestinal endoscopy does not predict those at risk of bleeding.

BACKGROUND AND STUDY AIMS: Routine coagulation screening prior to gastrointestinal endoscopy is performed in many centres in the UK, despite the lack of any evidence to support the practice. The aim of this study was to assess the benefits of routine pre-endoscopy coagulation screening in children and to assess how widespread this practice is in the UK. PATIENTS AND METHODS: We performed a retrospective analysis of the case notes of 250 consecutive patients who had undergone routine coagulation screening prior to endoscopy and biopsy, in accordance with our unit's protocol, looking for evidence of abnormal results or episodes of bleeding. We also performed a telephone survey of the protocols for coagulation screening at other paediatric units in the UK which are known to perform gastrointestinal endoscopy on a routine basis. RESULTS: According to our hospital's laboratory reference ranges, 16.8 % of the children who underwent endoscopy and biopsy had abnormal clotting. This was neither clinically significant nor associated with an increased bleeding risk in any patient. Of the 23 UK paediatric gastroenterology centres surveyed, including our own, five (21.7 %) perform routine coagulation screening before endoscopy. CONCLUSIONS: This study suggests that, although it is a relatively common practice, routine coagulation screening is not indicated in children who are undergoing gastrointestinal endoscopy and biopsy, and that it does not predict those at risk of significant bleeding. We would therefore suggest that if pre-endoscopy screening is to be performed, it should be reserved for those who are potentially at high risk of bleeding.

Blood Coagulation Disorders↗
PubMed2006

Management of fulminating ulcerative colitis in childhood with chimeric anti-CD25 antibody.

Fulminating acute ulcerative colitis (UC) is a potentially life threatening medical emergency. Up to 30% of individuals respond poorly to corticosteroids alone and second line medical or surgical therapies are indicated. We describe the successful use of chimeric anti-CD25 therapy in 4 such children poorly responsive to combined therapy with intravenous steroids and calcineurin inhibitors with a pretreatment predictive risk of colectomy of 85-100%. Clinical disease activity scores normalized within 72 hours of anti-CD25 administration and colonic histology provided evidence of mucosal healing within 10-14 days. None required emergency colectomy. Anti-CD25 is efficacious in fulminating UC and randomized placebo controlled trials appear indicated.

Acute Disease↗
PubMed2006

Systemic vasculitis: a cause of indeterminate intestinal inflammation.

OBJECTIVES: Indeterminate intestinal inflammation may result from a variety of inflammatory conditions in addition to ulcerative colitis and Crohn disease. The primary systemic vasculitides may present with intestinal inflammation and an indeterminate colitis. We set out to describe a series of children with primary systemic vasculitis who initially presented with clinical features suggestive of inflammatory bowel disease (IBD) to establish criteria that might help discriminate between IBD and primary systemic vasculitis. METHODS: Ten children (6 boys, median age at presentation 8.9 years, range 0.9-14.5 years) satisfied inclusion criteria. RESULTS: All had abdominal pain, weight loss, diarrhea (6 of 10 bloody) and laboratory evidence of a severe acute phase response. Extraintestinal clinical features included vasculitic rash, renal impairment, myalgia, testicular pain and polyarthritis. Endoscopy showed vascular changes or other macroscopic findings suggestive of vasculitis in 5 of 10 patients. Gut histology revealed indeterminate chronic inflammatory mucosal changes and one patient with small artery fibrinoid necrosis in the submucosal vessels. Extraintestinal biopsy was performed in 6 patients and had a higher yield for the demonstration of vasculitis than intestinal biopsy. The results of selective visceral angiography was suggestive of vasculitis in all patients, but was normal in 7 cases of treatment-unresponsive classic IBD. Treatment comprised corticosteroid and azathioprine in all patients. Cyclophosphamide was given to 7 of 10 patients. CONCLUSIONS: Extraintestinal manifestations and inflammatory responses that may be disproportionate to the degree of intestinal inflammation provide clues to the presence of an underlying primary systemic vasculitis, and these data suggest that selective visceral angiography plays a key role in the diagnosis of vasculitis in this context. It is important to identify and treat any vasculitic component because failure to do so may result in consequential morbidity or mortality.

Abdominal Pain↗
PubMed2005

Bilateral intraparotid and extraparotid Warthin's tumours.

Warthin's tumour is a benign adenoma in the parotid gland, but extraparotid and synchronous bilateral Warthin's tumours may occur. In this report, we describe a patient with simultaneous bilateral involvement of the parotid glands and neck by multiple Warthin's tumours, an occurrence not previously described.

Adenolymphoma↗
PubMed2005

Prediction of the capacitance line shape in two-channel quantum dots.

We propose a setup to realize two-channel Kondo physics using quantum dots. We discuss how the charge fluctuations on a small dot can be accessed by using a system of two single-electron transistors arranged in parallel. We derive a microscopic Hamiltonian description of the setup that allows us to make the connection with the two-channel Anderson model (of extended use in the context of heavy-fermion systems) and in turn make detailed predictions for the differential capacitance of the dot. Its line shape, which we determined precisely, shows a robust behavior that should be experimentally verifiable.

Journal Article↗
PubMed2005

An extraction complicated by lateral and medial pterygoid tethering of a fractured maxillary tuberosity.

We report a case in which the extraction of an upper second molar was complicated by a maxillary tuberosity fracture. Delivery of the tooth and bone fragment under local anaesthesia was unable to be achieved because of pain, brisk bleeding and tethering by the lateral and medial pterygoid muscles. The eventual removal of the fragment under general anaesthetic required the control of haemorrhage deep within the infratemporal fossa. When this complication is recognised by the general dentist the maxillary tuberosity should not be removed and the patient referred to a specialist unit.

Exostoses↗
PubMed2005

Fluctuation conductivity of thin films and nanowires near a parallel-field-tuned superconducting quantum phase transition.

We calculate the fluctuation correction to the normal state conductivity in the vicinity of a quantum phase transition from a superconducting to a normal state, induced by applying a magnetic field parallel to a dirty thin film or a nanowire with thickness smaller than the superconducting coherence length. We find that at zero temperature, where the correction comes purely from quantum fluctuations, the positive "Aslamazov-Larkin" contribution, the negative "density of states" contribution, and the "Maki-Thompson" interference contribution are all of the same order and the total correction is negative. Further, we show that, based on how the quantum critical point is approached, there are three regimes that show different temperature and field dependencies which should be experimentally accessible.

Journal Article↗
PubMed2005

A jig for measuring incisor inclination.

The aim of this study was to design and construct a jig for measuring the inclination of the upper incisors to the maxillary plane and of the lower incisors to the mandibular plane. After several prototypes had been tested, the required properties for a successful jig were identified and a simple inexpensive device was produced. Measurements obtained when using the jig on 51 subjects were compared with cephalometric values by means of regression analysis. This revealed that measurements obtained using the jig against the upper and then the lower incisor crowns could be converted to cephalometric incisor angulations with 96 per cent accuracy to 10 degrees, by adding 23 and 3 degrees, respectively. The jig was accurate to 5 degrees on 69 per cent of occasions for the upper teeth. The 5 degrees accuracy with the lower incisors was only 27 per cent, although over a 6 degree range it improved to 78 per cent. For upper and lower tooth measurements combined, the jig was accurate to within 6 degrees on 75 per cent of occasions.

Cephalometry↗
PubMed2005

Hypertrophic eosinophilic gastroenteropathy is associated with reduced enterocyte apoptosis.

AIMS: To investigate the cause of grossly elongated villi in four children presenting with obstruction due to a novel form of eosinophilic gastroenteropathy in which there was profound hyperplasia of the intestinal villi with grossly increased villous/crypt ratio and prominent mucosal eosinophilia. Increased eosinophils were also present in the muscularis propria and submucosa. All had intermittent diarrhoea and signs of a protein-losing enteropathy. METHODS AND RESULTS: The cause of the grossly elongated villi was investigated by studying enterocyte proliferation (Ki67), survival factors (bcl-2) and apoptosis (TUNEL) in these patients (n = 4) and normal (jejunum n = 6, ileum n = 6) and disease (n = 6) controls. The most remarkable finding was that apoptotic enterocytes were undetectable in the elongated villi. CONCLUSIONS: It seems likely that a defect in the regulation of apoptosis of the epithelium occurs which could explain the remarkable hyperplasia of the villi seen.

Adolescent↗
PubMed2005

Characterization of ultrafine coal fly ash particles by energy-filtered TEM.

In this study, energy-filtered transmission electron microscopy is demonstrated to be a valuable tool for characterizing ultrafine coal fly ash particles, especially those particles encapsulated in or associated with carbon. By examining a series of elemental maps (K-edge maps of C and O, and L-edge maps of Si, Al, Ti and Fe) recorded using the three-window method, considerable numbers of titanium and iron species with sizes from several nanometres to submicrometre were shown to be present, typically as oxides dispersed in the carbonaceous matrix. Crystalline phases, such as rutile and iron-rich oxide spinel, were also identified from electron diffraction patterns and high-resolution TEM images. Information about these ultrafine coal fly ash particles regarding their size, morphology, elemental composition and distribution, and crystalline phases, which has not been available previously in conventional ash studies, should be useful in toxicological studies and related environmental fields.

Air Pollutants↗
PubMed2005

Need for gerodontology education in India.

OBJECTIVES: To evaluate the status and need for education in Geriatric Dentistry in India. MATERIALS AND METHODS: The status of dental education in India was studied. India has 185 dental schools producing 12 000 dental graduates every year. At postgraduate level, there are nine recognised specialities in Dentistry, and approximately 58 institutions offer 1160 places for postgraduate degree courses. Dental education is shaped and administered by the Dental Council of India. RESULTS: So far, Geriatric dentistry has not developed as a separate, independent speciality at postgraduate level. The undergraduate curriculum does not have any significant component of geriatric dentistry. The lack of training results in poor understanding of special needs of older adults in young graduates. Without adequate training and personal experience of growing old, young graduates may not be able to understand the physical, socio-economic and psychological problems of the elderly and the complexities involved in treatment planning for patients with multiple chronic diseases and medication. CONCLUSIONS: It is emphasized that geriatric dentistry should be included in each of the pre-clinical, para-clinical and clinical subjects at the undergraduate level. Graduate students should be encouraged to treat elderly patients in clinics under supervision using a multi-disciplinary approach. Also, postgraduate diploma and degree courses in geriatric dentistry should be developed to address the needs of the vast elderly population in India.

Aged↗
PubMed2004

Treatment of uterine sarcoma at the Royal Marsden Hospital from 1974 to 1998.

AIMS: Uterine sarcomas are rare tumours with histopathological diversity characterised by rapid clinical progression and poor prognosis. Optimal management consists of complete surgical removal, but is not clear whether adjuvant radiotherapy improves the prognosis. The aim of this retrospective study was to investigate the clinical and histopathological characteristics together with treatment and outcome of patients with uterine sarcomas. MATERIALS AND METHODS: Records of 100 patients treated at the Royal Marsden Hospital between 1974-1998 were reviewed: 47 leiomyosarcoma (LMS), 30 mixed mullerian tumours (MMT), 19 endometrial stromal sarcoma (ESS), one haemangiopericytoma, one rhabdomyosarcoma and two unspecified sarcoma. There were 50, 11, 21 and 18 patients with stage I, II, III and IV carcinoma, respectively. Thirty-four patients had high-grade disease. Fifty-three patients received adjuvant radiotherapy. The median age was 55 years (range: 18-83 years). The median follow-up was 54 months (range: 3 months to 27 years). RESULTS: The overall 3, 5 and 10-year survival rates were 39%, 30% and 20%, respectively. Survival was significantly related to stage (P = 0.002), grade (P = 0.003) and histological type (P = 0.04), but not to use of postoperative irradiation. At 3 years, the survival rate was 42% for LMS, 22% for MMT and 63% for ESS. Local recurrence rate, however, was significantly improved after adjuvant radiotherapy with dose higher than 50 Gy (P = 0.001). CONCLUSIONS: Prognosis is dependent on histopathological sub-type, grade and tumour stage. Adjuvant radiotherapy decreases local recurrence rate, but without significant impact on survival.

Adolescent↗