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Biomedical subjects

C Roy

Publications and source records attributed to C Roy.

At least 361 records · Page 20Linked to original sources
PubMedDate not supplied

Potential role of duplex Doppler sonography in acute renal colic.

PURPOSE: We assessed the value of renal duplex Doppler sonography in diagnosing obstruction in patients with acute renal colic. METHODS: We compared the results of renal duplex Doppler sonography with those of intravenous urography (IVU) in 65 patients presenting with symptoms of renal colic. The Doppler spectral waveforms were used to calculate the resistance index (RI). The difference between the mean RIs (delta RI) in the 2 kidneys was calculated for each patient. The sensitivity, specificity, and accuracy of delta RI for the diagnosis of obstruction were calculated with several discriminatory thresholds. RESULTS: All patients had an obstruction on IVU. When a high delta RI threshold for obstruction (delta RI > or = 0.1) was applied, the sensitivity and specificity of duplex Doppler sonography were 10% and 80%, respectively. When the delta RI threshold was decreased, the sensitivity increased but the specificity decreased, and both remained quite low. Twelve patients had a lower mean RI in the obstructed kidney than in the normal contralateral kidney. Among 14 patients without pyelocaliceal dilatation, the sensitivity of duplex Doppler sonography was 70% with a delta RI threshold of 0.03. CONCLUSIONS: Duplex Doppler sonography is not sensitive enough to diagnose obstruction in patients with acute renal colic.

Acute Disease↗
PubMedDate not supplied

Duplex Doppler sonography of the flaccid penis: potential role in the evaluation of impotence.

PURPOSE: Duplex Doppler sonography of the cavernosal arteries of the penis with intracavernous injection (ICI) of vasoactive agents has been widely used to evaluate arterial insufficiency in impotence. Our goal was to assess the potential value of peak systolic velocity (PSV) measurements on the flaccid penis in the diagnosis of arteriogenic impotence. METHODS: Forty-four men underwent duplex Doppler sonography with PSV measurements before and after ICI of prostaglandin E(1). Three different cutoff values for lowest normal PSV before injection-5 cm/second, 10 cm/second, and 15 cm/second-were tested. RESULTS: Thirteen patients had arteriogenic insufficiency based on post-ICI duplex sonography and clinical response. Results for our different cutoff PSV values of 5 cm/second, 10 cm/second, and 15 cm/second in diagnosing arteriogenic impotence were, respectively: sensitivity 29%, 96%, and 100%; specificity 100%, 92%, and 23%; negative predictive value 80%, 92%, and 100%; positive predictive value 100%, 81%, and 41%; and overall accuracy 79%, 93%, and 44%. In the flaccid state, there was a significant difference in mean PSV between the "normal" group (12.6 +/- 0.9 cm/second) and the arteriogenic impotence group (7.7 +/- 1.1 cm/second). Twenty-nine patients with a bilateral PSV of 10 cm/second or less before ICI had a normal clinical response. CONCLUSIONS: A cutoff PSV value of 10 cm/second in the flaccid state had the best accuracy in predicting arterial insufficiency. Duplex Doppler sonography is proposed as the initial test to evaluate the penile arterial supply and to determine whether patients are good candidates for therapy with ICI.

Adult↗
PubMedDate not supplied

Activity of ciprofloxacin (BAYo 9867) against Pseudomonas aeruginosa and ampicillin-resistant Enterobacteriaceae.

We studied the in vitro activity of ciprofloxacin against 570 strains of ampicillin-resistant Enterobacteriaceae and 286 Pseudomonas aeruginosa strains. 95.26% of the Enterobacteriaceae and 53.45% of the P. aeruginosa were inhibited by 0.1 mg/l of ciprofloxacin. 2 mg/l of ciprofloxacin inhibited all of the Enterobacteriaceae strains and 4 mg/l all of the P. aeruginosa. We compared the activity of ciprofloxacin with that of temocillin in the Enterobacteriaceae strains. In the P. aeruginosa strains, classified according to their susceptibility to carbenicillin and gentamicin, we compared the activity of ciprofloxacin with that of ceftazidime. In the strains studied, the in vitro activity of ciprofloxacin is superior to that of temocillin against the Enterobacteriaceae and to that of ceftazidime against the P. aeruginosa strains.

Ampicillin↗
PubMedDate not supplied

Hydro-osmotic activity of "carba' analogues of oxytocin and [8-arginine] vasopressin on frog (Rana esculenta) bladder.

The biological potency of neurohypophysial hormone analogues in stimulating water transport across the frog bladder (Rana esculenta) was estimated from the pD2 (negative logarithm of the peptide concentration eliciting 50% of its maximal hydroosmotic effect) and from the maximal response. Most analogues elicited maximal responses similar to those of the natural hormones. Both replacement of sulfur by a methylene group in the disulfide bridge and omission of the terminal amino group in oxytocin reduced hydroosmotic activity; carba substitution in oxytocin led to a greater drop in pD2 than the same substitution in deamino-oxytocin. On the contrary, the effects of substituting phenylalanine for tyrosine and of omitting the amino group were almost additive. Elimination of the carboxyl-terminal tripeptide sequence considerably reduced hydroosmotic potency; pressinamide was inactive up to 3 mug/ml. The highly potent antidiuretic peptides, deamino-[D-Arg8]vasopressin and deamino-6-carba-]D-Arg8]vasopressin, were weakly active in the hydroosmotic assay.

Amino Acid Sequence↗
PubMedDate not supplied

A preventive program for community-dwelling elderly at risk of functional decline: a pilot study.

A program has been designed to assess and survey community-dwelling elderly over 75, identified at risk of functional decline by a postal questionnaire. The objectives were to verify the acceptability and the feasability of the program and to explore its impact, mainly on the functional status. A randomized controlled study took place in an urban community where 99 participants were drawn from those having responded positively to two or more of the six questions asked in the postal questionnaire, previously studied in Sherbrooke, in 1992. The program consisted in a home visit by a nurse who administered a standardized assessment battery on risk factors identified specifically for functional decline. When problems were identified, experimental subjects were referred to their general practitioner or to other health professionals for diagnosis and interventions. The control subjects received the usual health services. Both process and outcome measures were utilized in the study. The process measures allowed to know whether the program was acceptable or not to subjects and if it was feasible when using the existing health care services. The outcome measures included the number of eliminated risk factors, the functional autonomy level, the general well-being, the perceived state of health and the social support. The results showed that the program was feasible to implement and acceptable by the subjects and by health professionals. After 6 months, study subjects did not loose autonomy whereas the control ones significantly declined (P<0.001). If preventive programs could be effective in reducing the loss of autonomy, the use and cost of health care services could also be reduced and the other health and wellfare problems could be also prevented.

Journal Article↗
PubMedDate not supplied

[Urology].

Explore the source record for details and available documents.

Contrast Media↗
PubMedDate not supplied

(AAT)n repeat in the cannabinoid receptor gene (CNR1): association with cocaine addiction in an African-Caribbean population.

Owing to their agonist action on dopaminergic systems, cannabinoids may play a major role in substance dependency and schizophrenia. We examined the (AAT)n triplet repeat polymorphism nearby the CNR1 gene, which encodes human cannabinoid (CB1) receptor, in a male Afro-Caribbean population. The allelic and genotypic distributions were significantly different in non-schizophrenic cocaine dependents (n = 97), schizophrenic cocaine dependents (n = 45) and matched controls (n = 88) (P < 10(-4)). The frequency of the (AAT)12 repeat allele was increased in non-schizophrenic cocaine dependents and schizophrenic cocaine dependents vs controls (25.3 and 26.7 vs 5.7%) (P < 10(-4)). Our results support that the (AAT)n polymorphism nearby the CNR1 gene could be associated with predisposition to cocaine dependency.

Adult↗
PubMedDate not supplied

Visual inspection with acetic acid and cytology in the early detection of cervical neoplasia in Kolkata, India.

Visual inspection of the cervix after application of 3-5% acetic acid (VIA) is a potential alternative to cytology for screening in low-resource countries. The present study evaluated the performance of VIA, magnified visual inspection after application of acetic acid (VIAM), and cytology in the detection of high-grade cervical cancer precursor lesions in Kolkata (Calcutta) and suburbs in eastern India. Trained health workers with college education concurrently screened 5881 women aged 30-64 years with VIA, VIAM, and conventional cervical cytology. Detection of well-defined, opaque acetowhite lesions close to the squamocolumnar junction; well-defined, circumorificial acetowhite lesions; or dense acetowhitening of ulceroproliferative growth on the cervix constituted a positive VIA or VIAM. Cytology was considered positive if reported as mild dysplasia or worse lesions. All screened women (N = 5881) were evaluated by colposcopy, and biopsies were directed in those with colposcopic abnormalities (N = 1052, 17.9%). The final diagnosis was based on histology (if biopsies had been taken) or colposcopic findings, which allowed direct estimation of sensitivity, specificity, and predictive values. Moderate or severe dysplasia or carcinoma in situ (CIN 2-3 disease) was considered as true positive disease for the calculation of sensitivity, specificity, and predictive values of screening tests. 18.7%, 17.7% and 8.2% of the women tested positive for VIA, VIAM, and cytology. One hundred twenty two women had a final diagnosis of CIN 2-3 lesions. The sensitivities of VIA and VIAM to detect CIN 2-3 lesions were 55.7% and 60.7%, respectively; the specificities were 82.1% and 83.2%, respectively. The sensitivity and specificity of cytology were 29.5% and 92.3%, respectively. All the tests were associated with negative predictive values above 98%. VIA and VIAM had significantly higher sensitivity than cytology in our study; the specificity of cytology was higher than that of VIA and VIAM.

Acetic Acid↗
PubMedDate not supplied

Evaluation of RARE-MR urography in the assessment of ureterohydronephrosis.

OBJECTIVE: The goal of this prospective study was to evaluate the value of the fast imaging sequence called RARE-MR urography (RMU) for the diagnosis of ureterohydronephrosis. MATERIALS AND METHODS: Sixty-nine patients underwent this procedure. The results were compared with those obtained by intravenous urography (IVU) and ultrasonography (US). RESULTS: The accuracy of RMU in the detection of urinary tract dilatation and the localization of the level of obstruction was excellent (100%). The determination of the type of obstruction, intrinsic versus extrinsic, was 80% by IVU and 60% for RMU. The RMU sequence alone could not specify the nature of the obstruction. Functional information about the obstructed collecting system could not be obtained. CONCLUSION: The RMU technique may be considered in the following circumstances: contraindications to IVU (allergy to contrast medium, severe renal failure), impairment of renal excretion, and failure to locate the level of obstruction by US. The absence of ionizing radiations favors the promotion of this procedure to study ureterohydronephrosis during pregnancy.

Adult↗
PubMedDate not supplied

CT-guided interventional procedures for pain management in the lumbosacral spine.

The lumbosacral spine is the source of pain, suffering, and disability more frequently than any other part of the body. Pain in the lower back can be managed with computed tomography-guided analgesic interventional procedures, such as periradicular infiltration, percutaneous laser disk decompression, facet joint block, and percutaneous vertebroplasty. Periradicular injection of steroids provides short-term and sometimes even long-term relief of low back pain. Percutaneous laser disk decompression is used to treat radiculalgia caused by disk herniation. Facet joint block is useful in diagnosis and treatment of facet syndrome. Percutaneous vertebroplasty provides short- and long-term pain relief in patients with vertebral body disease. However, precise patient selection is essential to the success of each of these techniques. The interventional radiologist has an active role to play in minimally invasive management of lower back pain and should be part of an interdisciplinary team that determines the appropriate therapy.

Humans↗
PubMedDate not supplied

Imaging of chest wall disorders.

Pathologic processes that may involve the chest wall include congenital and developmental anomalies, inflammatory and infectious diseases, and soft-tissue and bone tumors. Many of these processes have characteristic radiologic appearances that allow definitive diagnosis. Sternal deformities can be visualized at radiography and their severity quantified with computed tomography (CT). In cervical rib, CT with multiplanar reconstruction may demonstrate relevant anatomic detail and the relationship between bone deformity and arterial compression. In Poland syndrome, radiography reveals an area of hyperlucency on the affected side, whereas CT demonstrates the absence of the greater pectoral muscle and clearly depicts associated musculoskeletal anomalies. Tuberculosis typically manifests at radiography and CT as osseous and cartilaginous destruction and soft-tissue masses with calcification and rim enhancement. Aspergillosis involving the chest wall manifests as pulmonary consolidations and permeative osteolytic changes of the rib and spine at CT and as an area of increased signal intensity at T2-weighted magnetic resonance (MR) imaging. Neurogenic tumors and hemangiomas also typically have high signal intensity at T2-weighted MR imaging. Apparent mass extension or unequivocal bone destruction seen at CT or MR imaging may indicate chest wall involvement by lymphoma. Radiologically, soft-tissue sarcomas typically appear as areas of soft-tissue density or attenuation, often associated with necrotic areas of low density or attenuation. At radiography, plasmacytoma typically manifests as well-defined, "punched-out" lytic lesions with associated extrapleural soft-tissue masses. Chondrosarcoma frequently appears as a large, lobulated excrescent mass arising from a rib with scattered flocculent calcifications characteristic of its cartilaginous mix. Familiarity with these radiologic features facilitates accurate diagnosis and optimal patient treatment.

Adolescent↗