Biomedical subjects

D Anand

Publications and source records attributed to D Anand.

At least 19 recordsLinked to original sources

PubMed2003

Lung function and respiratory health in adolescents of very low birth weight.

AIMS: To determine if very low birth weight (VLBW; birth weight <1500 g) is associated with reduced lung function and respiratory health in adolescence and, if it is, whether this impairment is associated with prematurity or intrauterine growth restriction. METHODS: A geographically defined cohort of 128 VLBW infants and an age, sex, and school matched comparison group born in 1980/81 were studied. The cohort and comparison group were assessed at 15 years of age. The birth weight ratio of the index cases (observed birth weight/expected birth weight for the gestation) was determined to assess the degree of growth restriction. Respiratory support received during the neonatal period was obtained from hospital records. Smoking habits and respiratory morbidity were obtained through questionnaires. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and forced expiratory flow when 25-75% of FVC is expired (FEF(25-75%)) were measured using a portable spirometer. The values are expressed as percentage predicted for height, age, and gender using standard reference values. Adjustments were made for smoking habits of mother and children. RESULTS: The differences in means between index and comparison groups for FEF(25-75%) (-12.42%; p < 0.001) and FEV1/FVC (-3.53%; p < 0.001) ratio were statistically significant. The differences in FVC and FEV1 were not significant. No correlation was found between the birth weight ratio and lung function among the index cohort. Chronic cough, wheezing, and asthma were more common among the index cohort than in the comparison group. Within the index group, there was no difference in lung function between those who received and those who did not receive respiratory support. CONCLUSION: Adolescents who were VLBW compared with matched controls showed medium and small airways obstruction. This was associated with prematurity rather than intrauterine growth restriction or having received respiratory support during the neonatal period. The index VLBW cohort compared with their controls were also more prone to chronic cough, wheezing, and asthma.

Adolescent↗

PubMed2001

Compact storage of medical images with patient information.

Digital watermarking is a technique of hiding specific identification data for copyright authentication. This technique is adapted here for interleaving patient information with medical images to reduce storage and transmission overheads. The text data are encrypted before interleaving with images to ensure greater security. The graphical signals are compressed and subsequently interleaved with the image. Differential pulse-code-modulation and adaptive-delta-modulation techniques are employed for data compression, and encryption and results are tabulated for a specific example.

Computer Security↗

PubMed2000

Noninvasive measurements for studying the tumoral pharmacokinetics of platinum anticancer drugs in solid tumors.

An effective methodology to determine the amount of cisplatin or carboplatin at the solid tumor site in a noninvasive manner may enable clinicians to design drug regimens based on an individual's in situ pharmacokinetics. Such noninvasive methods may allow optimization of an individual's drug exposure at the target site, as well as provide a screening measure to determine individual efficacy based on exposure to these platinated drugs. 195mPt appears to be the radionuclide of platinum most suitable for radiolabeling cisplatin or carboplatin, and an analysis is presented of the methods available for preparing such radiolabeled drugs. The use of this methodology is illustrated in detail in studies in animals, as well as some preliminary studies in humans. The animals used were Sprague Dawley rats bearing the Walker 256 carcinoma, and drug biodistribution was studied following administration of cisplatin or carboplatin radiolabeled with 195mPt. This radionuclide permitted noninvasive imaging of the drug and its metabolites at the tumor site and at selected organs. The results obtained show an ability to estimate the amount of platinated drug species in the tumor environment using a noninvasive methodology. Various compartmental models were tested, some of which could be validated experimentally. This noninvasive method is able to provide individual estimates of the active component of the drug at the target site, and is therefore a method that can be implemented in human studies.

Animals↗

PubMed2000

Errors in registered birth weight and its implications for mortality statistics.

BACKGROUND: Birth weight mortality statistics are important for examining trends and monitoring the outcomes of neonatal care. AIM: To determine the effects of errors in the registered birth weight on birth weight specific mortality. METHODS: All twins born in England and Wales during 1993-95 comprise the denominator population. For those twins that died, the Office for National Statistics (ONS) provided copies of the death certificates. From the information on the death certificates, the registered birth weight was validated and amended using predetermined rules. The neonatal, postneonatal, and infant mortality rates were recalculated. RESULTS: In 2.5% of cases the registered birth weight was "not stated" and in others there were miscoding errors. Important differences between published and amended birth weight specific mortality rates especially in <500 g and >/=3500 g groups were evident. CONCLUSIONS: The bias arising from these errors should be taken into account in interpreting mortality rates and their trends.

Birth Weight↗

PubMed1996

Evaluation of the home pad test in the investigation of female urinary incontinence.

OBJECTIVE: To evaluate the use of the home pad test in the management of patients with urinary dysfunction with reference to feasibility, normal data, reproducibility, compliance and accuracy when compared to video urodynamics. DESIGN: A prospective study to determine 1. the accuracy of weighing pads by healthcare workers compared to weighing by patients with a spring balance; 2. the effects of evaporation; 3. the pad weight increase in continent women; 4. the compliance over 194 tests in terms of acceptability and feasibility; 5. the reproducibility in 112 women for the 24 h and 48 h tests, 6. the comparison with video urodynamic studies in 149 patients. SETTING: A London teaching hospital. MAIN OUTCOME MEASURES: Coefficient of variation and mean deviation analysis were employed to determine the accuracy of measurement. Percentage changes in standardised wet pad weights over a period of 8 weeks were used to determine the rate of weight loss due to evaporation. The percentage of patients completing the test satisfactorily was documented. The increase in the weights of all pads worn during the test period was measured in continent volunteers and incontinent patients. Video urodynamic diagnoses were used as the Gold Standard for comparison. RESULTS: Twelve perineal pads were weighed by 15 healthcare workers with a resulting coefficient of variation equal to 1.55% (standard error = 0.09%). The mean deviation between patient-measured pad weights and staff-measured weights was 49% (SD = 132%). Pads wetted with saline showed no difference in weight after 1 week and less than 5% change in weight after 8 weeks, with the upper 95% confidence limit of less than 10% loss. The mean pad weight increase over 48 h in continent women was 7.13 g (SD = 4.32 g) giving a 95% upper confidence level of less than 15 g. Compliance was reasonably high with 161 (83%) carrying out the test perfectly. Test-retest analysis of the 24 h and 48 h tests showed a strong relationship with correlation coefficients of 0.90 and 0.94 respectively. The reproducibility was also good, with differences as a percentage of the mean between the first and second test being 6.9% and 1.6% for the 24 h and 48 h tests respectively. There was good concordance when the urodynamic study data was compared with pad weight data in terms of incontinence compared with no incontinence (kappa = 0.65), but a high false positive rate was detected for the pads. When eight of these patients with a false positive pad test had repeat video urodynamic studies, six were found to have detrusor instability on the second study. CONCLUSIONS: The home pad test combined with frequency volume chart documentation is an easy test to perform. It is quite robust and reasonably reproducible. This test should be added to complement the routine urodynamic tests and may have a role in detecting occult detrusor instability.

Female↗

PubMed1992

A new, semi-automated system for the micro-scale synthesis of [195mPt]cisplatin suitable for clinical studies.

A new, semi-automated system for the microscale synthesis of [195mPt]cisplatin has been developed. Radiochemical yields of up to 70% of pure [195mPt]cisplatin can be obtained routinely e.g. 555-629 MBq (15-17 mCi) from 925 MBq (25 mCi) of [195mPt]Pt metal. Chemical losses during synthesis, and radiation exposure of personnel, have been minimized. These increased yields are the consequence of the elimination of most transfers, and enhanced yields at most steps: ammination losses decreased from 27 to 7%, and at the diiodo- to di-acquo- conversion, from 34 to 11%. The versatility of such a system is discussed.

Cisplatin↗

PubMed1991

Symptoms analysis for the diagnosis of genuine stress incontinence.

OBJECTIVE: To determine the accuracy of an analysis of symptoms alone for the diagnosis of genuine stress incontinence. DESIGN: A comparison of results of symptoms analysis with urodynamic findings. SETTING: A gynaecological video-urodynamic unit. SUBJECTS: 252 consecutive patients referred for urodynamic investigations. INTERVENTIONS: A questionnaire of 20 symptoms of lower urinary tract dysfunction, midstream specimen of urine, pad testing, uroflowmetry, and video-cystourethrography. MAIN OUTCOME MEASURES: Using the urodynamic diagnosis as the 'gold standard', the accuracy of discriminant function analysis of symptoms was determined. RESULTS: Symptoms analysis achieved a correct classification of 81% with a false positive rate of 16%. Use of an accumulative probability curve defines patients who fall into the equivocal range. CONCLUSIONS: All women presenting with incontinence should undergo preoperative urodynamic studies.

Female↗

PubMed1976