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S King

Publications and source records attributed to S King.

At least 109 records · Page 6Linked to original sources

Renal calcification in preterm infants: follow up at 4-5 years.

AIM: To determine the consequences of renal calcification in preterm infants. METHODS: A cohort of 11 preterm babies was studied at the age of 4 to 5 years. They had had renal calcification as neonates. Seventeen matched controls were also studied. Each child had a renal ultrasound scan, a calcium load test, and a desmopressin test for renal concentrating ability (RCA). The study group also had glomerular filtration rate (GFR) estimated, using the height:creatinine ratio, and tubular phosphate reabsorption, without phosphate load, per glomerular filtration rate (Tp/GFR) calculated, RESULTS: In the study group the median GFR was 61 ml/min/1.73m2 (range 46-79 ml/min/1.73m2) and the median calculated Tp/GFR SD score was -0.94 (range -2.8-0.68). Five children out of the study group had ultrasonic evidence of renal calcification. There was no significant difference between the two groups in renal size, calciuria, before or after calcium load, or RCA. Eight children (three patients, five controls) had an abnormal calcium load test. The RCA of the children in the study and control groups combined was below that of published values, with a median calculated SD score -0.71 (95% CI -1.21 to -0.23). CONCLUSIONS: There was evidence of renal dysfunction in children who had been born preterm. Renal calcification detected in the neonatal period does not seem to be a major predisposing factor for the abnormalities of renal function subsequently observed in these infants.

Calcinosis↗

"Tasks".

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Humans↗

Signal characteristics of tumors shown by high-resolution endorectal coil magnetic resonance imaging may predict outcome among patients with cervical carcinoma treated with irradiation. A preliminary study.

BACKGROUND: The purpose of this study was to evaluate the role of high-resolution magnetic resonance imaging with the endorectal coil (eMRI) in the management of cervical carcinoma treated with definitive irradiation. METHODS: Eighteen patients with invasive cervical carcinoma (International Federation of Gynecology and Obstetrics Stages Ib-IIIb) consented to evaluation with eMRI on a 1.5 tesla system with high resolution (400 x 400 microM). Images were read to provide staging information and to grade the signal characteristics of the individual tumors as low (dark), intermediate, or high (bright) relative to surrounding isointense fat. Patients were treated with standard megavoltage irradiation (prescribed dose, 80-85 Gray); shaped antero-posterior/postero-anterior or 4-field box techniques, plus brachytherapy, were used. RESULTS: In 39% of patients, tumors were determined to be in a higher stage by eMRI because of proximal vaginal involvement (n = 4) or the combination of proximal vaginal involvement and parametrial extension (n = 3). Features predictive of improved local control and survival without evidence of disease included stage, hemoglobin levels > or = 11, complete response to external irradiation, and bright signal characteristics. Compared with those who had dark and/or intermediate tumors, patients who had tumors with bright signal characteristics tended to present with earlier stage disease, were less likely to have anemia, and were more likely to have complete response to external irradiation. CONCLUSIONS: Prognostic information for clinical staging of cervical carcinoma was contributed by eMRI. The technique was more likely to suggest proximal vaginal involvement by a tumor than was examination under anesthesia. Signal characteristics of tumors may provide valuable predictive information that is supplementary to conventional discriminants of outcome that follow definitive irradiation. Such information could allow physicians to tailor treatment (e.g., by the addition of radiation sensitizers) at an earlier point in disease management.

Female↗

The influence of expressed emotion, family dynamics, and symptom type on the social adjustment of schizophrenic young adults.

BACKGROUND: The goal of this study was to test a path analytic model that reflects the hypothesis that family cohesion and family adaptability underlie family members' expressed emotion (critical comments and emotional overinvolvement), that these family variables underlie the preponderance of positive symptoms in a patient with schizophrenia 9 months after relatives are interviewed, and that all of these variables influence the patient's social adjustment at follow-up. METHODS: The subjects were 69 patients who met the DSM-III-R criteria for schizophrenia and 108 of their relatives. Relatives were assessed with the Camberwell Family Interview and the Family Adaptability and Cohesion Evaluation Scales III. Patients were interviewed 9 months later with the Brief Psychiatric Rating Scale and the Social Adjustment Scale II. RESULTS: Significant amounts of variance were explained by the model for three of the five social adjustment components. Neither family cohesion nor adaptability was associated with either critical comments or emotional overinvolvement. Family cohesion was negatively associated and emotional overinvolvement was positively associated with a preponderance of positive symptoms. Greater family adaptability was associated with lower social adjustment scores, and greater emotional overinvolvement was associated with higher social adjustment. Cohesion had a significant positive indirect effect on social adjustment through its association with symptom type. CONCLUSIONS: Critics of expressed emotion will be pleased to see that one component of high expressed emotion (emotional overinvolvement) is actually associated with a better social outcome in patients. Proponents of the expressed emotion concept will be pleased to see the applicability of expressed emotion to other facets of schizophrenic outcome. The results highlight the importance of using the expressed emotion scales in their continuous rather than dichotomized state and of analyzing critical comments and emotional overinvolvement separately.

Adolescent↗

Asymmetric bioreduction of a ketosulfone to the corresponding trans-hydroxysulfone by the yeast Rhodotorula rubra MY 2169.

A microbial screen identified the yeast Rhodotorula rubra MY 2169 as a suitable biocatalyst for the asymmetric bioreduction of a ketosulfone (5,6 dihydro-6(s)-propyl-4H-thieno[2,3b] thiopyran-4-one-7,7-dioxide) to the corresponding trans-hydroxysulfone. This synthesizer is a precursor to the carbonic anhydrase inhibitor L-685,393, a new drug candidate targeted for the treatment of ocular glaucoma. Process development studies revealed that the rate of bioreduction was sensitive to temperature, pH, solvent concentration and the physiological state of the yeast cells. The maximum specific bioreduction rate was achieved by employing cells harvested in the stationary phase of growth. The diastereomeric excess of the trans-hydroxysulfone produced was found to be only affected by the residual amount of ketosulfone present in the bioconversion medium; therefore, when close monitoring of the residual ketosulfone was implemented, the desired enantiomeric excess was achieved at harvest. When scaled up, this bioreduction process supported the production of gram quantities of highly optically pure trans-hydroxysulfone (diastereomeric excess > 96%).

Alcohols↗

Effect of increased interstitial fluid flux on fractional catabolic rate of high molecular weight [3H]hyaluronan injected in rabbit skin.

The removal rate of high molecular weight (M(r) 3 x 10(6) [3H]hyaluronan has been measured in rabbit paw skin in control and during increased local venous pressure induced by ligation of the femoral vein. The increased venous pressure resulted in a 20% increase of interstitial volume at 4 h after ligation, a value which relates to at least a doubling of lymph flow, i.e. also to doubling of fluid flux through the tissues. The fractional catabolic rate of hyaluronan was 0.0918 +/- 0.0170 h-1 (n = 10) and 0.0775 +/- 0.0206 h-1 (n = 11) in control and following increased venous pressure respectively (P > 0.05). Since the fractional catabolic rate of hyaluronan is not affected by increased venous pressure, the removal of hyaluronan via lymphatic drainage in rabbit paw skin must be small compared to the local turnover of the polysaccharide.

Animals↗

Development of drug targeting based on recombinant expression of the chicken avidin gene.

The chemistry required for covalent biotinylation of drugs, radiopharmaceuticals and other ligands is highly developed, and a large number of biotinylated reagents can be readily synthesized. In order to investigate whether expression of avidin cDNA in mammalian cells might be useful as part of a drug targeting strategy, we transiently expressed the avidin gene in two human tumor cell lines (the cervical carcinoma cell line, HeLa, and the liver derived line, Hep G2). Avidin protein as detected by either immunohistochemistry or binding of streptavidin-biotin complexes was present and functional following transient expression. This result indicated that the mechanisms underlying avidin oligomerization which are necessary for proper protein folding are present within mammalian carcinoma cell lines. Next, we generated a producer cell line (derived from psi2) capable of releasing a recombinant retrovirus encoding chicken avidin, and a tumorigenic murine breast cancer cell line (16/C) with stable avidin expression. We show that these cell lines are suitable for conferring functional expression of avidin in vitro. These experiments establish a means by which avidin gene expression can be explored as a mechanism for targeted gene delivery of biotin-derivitized drugs in vitro, and have important implications for utilization of this strategy in vivo.

Animals↗

Has improvement in PTCA intervention affected long-term prognosis? The NHLBI PTCA Registry experience.

BACKGROUND: The NHLBI Percutaneous Transluminal Coronary Angioplasty (PTCA) Registry followed 1345 consecutive patients with first PTCA between 1977 and 1981 (registry 1) and 2136 consecutive patients with PTCA between 1985 and 1986 (registry 2). Changes in patient selection and in immediate and 1-year outcome are presented. This report extends to 5 years the comparison of the effects of early and more recent management with PTCA. METHODS AND RESULTS: Sixteen participating centers entered consecutive patients who had angioplasty for the first time between 1977 and 1981 and between 1985 and 1986. Patients with recent myocardial infarction (MI) were excluded. Vessel disease was defined according to the Coronary Artery Surgery Study. Successful dilatation required > or = 20% reduction in luminal narrowing and < 50% lumen diameter stenosis after intervention. Routine annual follow-up was conducted by telephone interview. The product-limit method was used to estimate freedom from untoward events, Cox regression analysis to model relative risk and adjusted relative risk of events between the two registries, and logistic regression when the exact time of outcome (such as recurrence of symptoms) was not known. Long-term event rates were computed by vessel disease for all patients and for the cohort of patients with initially successful PTCA. After adjustment for extent of disease, diabetes, prior bypass surgery (CABG), hypertension, age, and sex, the 5-year risk of death was similar in the two registry cohorts. However, rates of MI, CABG, and a combined outcome measure of death, MI, and/or CABG were significantly lower in the registry 2 cohort both for all patients and for patients who were initially treated successfully. Use of repeated PTCA was higher, and freedom from symptoms without adverse events was significantly better in the latter cohort. CONCLUSIONS: Compared with registry 1, the management of the registry 2 cohort resulted in lower 5-year morbid event rates and reduced CABG operations. Mortality rates remained similar. When symptomatic status was considered in combination with events, a significantly better outcome was seen overall and in the initially successful cohort. In registry 2, repeated PTCA was used with much greater frequency early after the initial procedure.

Angioplasty, Balloon, Coronary↗

Improved treatment planning for the Syed-Neblett template using endorectal-coil magnetic resonance and intraoperative (laparotomy/laparoscopy) guidance: a new integrated technique for hysterectomized women with vaginal tumors.

The Syed template (Alpha-Omega Services, Bellflower, CA) represents an advance in interstitial gynecologic brachytherapy; however, its appeal is diminished by inaccuracies in target definition secondary to suboptimal imaging of gynecologic tumors and the risk of viscus perforation during a "blind" procedure. Magnetic resonance (MR) scanning with an endorectal coil and computed tomography were studied as a possible tool to improve target definition and maximize treatment planning with Syed templates. Abdominopelvic contents could be visualized directly through a laparotomy incision or indirectly with a laparoscopic video display to allow further target definition and minimize complications associated with blind procedures after hysterectomy. The synthesis of these techniques with Syed template applications was attempted to potentiate the utility of this brachytherapy system. Five patients with apical vaginal tumors which arose after previous hysterectomies (two endometrial cancer recurrences, one recurrent uterine sarcoma, two primary vaginal cancers) were referred for radiotherapy. In three cases, external beam pelvic radiotherapy (median dose, 45 Gy; range, 45-50.4 Gy) was delivered initially. In all cases, the Syed applicator was used for the brachytherapy component of the treatment. In two cases, high-resolution MR images (400 x 400 microns) of the vaginal apex were obtained after insertion of an endorectal surface coil. The images defined the relationships between the template, target volume, bladder, rectum, and intestine. The other three cases were planned with computerized tomography (CT). In all cases, intraoperative examination of the abdominopelvic contents was provided when laparotomy and/or laparoscopy was performed by the surgical team. The median brachytherapy dose prescribed to the isodose envelope covering the target volume was 40 Gy (range, 31-50 Gy). In all cases, the target volumes could be encompassed by the 60 cGy/hr isodose line. Tumor volume estimation was better with MR than CT. Procedure time was shorter with laparoscopy than with laparotomy. In two cases, bowel displacement was performed (one tissue expander, one omental sling) to prevent viscus perforation by interstitial needles. Four of five patients responded completely to the treatment. In three cases, local control was maintained at a median follow-up of 11 months. In conclusion, endorectal coil MRI may be advantageous to CT of the pelvis in that it allows preplanning to be achieved with greater precision and with less planning time. Major intraoperative complications (i.e., perforation of hollow viscus organs) can be avoided when the course of interstitial catheters is visualized from above by the surgical team.(ABSTRACT TRUNCATED AT 400 WORDS)

Brachytherapy↗