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S Malone

Publications and source records attributed to S Malone.

At least 37 records · Page 2Linked to original sources
PubMed1998

DNA-damaging steroidal alkaloids from Eclipta alba from the suriname rainforest1.

Bioassay-guided fractionation of the MeOH extract of Eclipta alba using three yeast strains (1138, 1140, and 1353) resulted in the isolation of eight bioactive steroidal alkaloids (1-8), six of which are reported for the first time from nature. The major alkaloid was identified as (20S)(25S)-22,26-imino-cholesta-5,22(N)-dien-3beta-ol (verazine, 3), while the new alkaloids were identified as 20-epi-3-dehydroxy-3-oxo-5,6-dihydro-4,5-dehydroverazine (1), ecliptalbine [(20R)-20-pyridyl-cholesta-5-ene-3beta,23-diol] (4), (20R)-4beta-hydroxyverazine (5), 4beta-hydroxyverazine (6), (20R)-25beta-hydroxyverazine (7), and 25beta-hydroxyverazine (8). Ecliptalbine (4), in which the 22,26-imino ring of verazine was replaced by a 3-hydroxypyridine moiety, had comparable bioactivity to verazine in these assays, while a second alkaloid (8) showed good activity against Candida albicans. All the alkaloids showed weak cytotoxicity against the M-109 cell line.

Alkaloids↗
PubMed1998

Neurologic deterioration after cervical spinal cord injury.

Neurologic deterioration after cervical spinal cord injury (SCI) at a regional spinal cord center was examined. This study examined the incidence of neurologic deterioration as well as associated risk factors in our patient population. Up to 5.8% of cervical SCI patients have been noted to deteriorate neurologically after admission. Risk factors have been early surgery, halo application, traction, and Stryker frame rotation. All cervical SCI patients admitted between 1978 and 1993 who had neurologic deterioration were studied for characteristics of their event, operative status, risk factors, mortality, and neurologic return at 1 year postinjury. Patients were divided into minor and major groups based on the degree of neurologic loss. Nineteen of 1,031 patients were identified as neurologically deteriorated (1.84%). There were 8 major and 11 minor group patients. The average time from injury to deterioration was 3.95 days. Of 10 patients undergoing surgery at < or =5 days, 8 deteriorated postoperatively. Potential risk factors were ankylosing spondylitis (three patients), sepsis (four patients), and intubation (four patients). Neurologic recovery at 1 year showed that 11 of 12 patients were improved. Neurologic deterioration occurred in 1.84% of our patients. Deteriorations were associated with surgery at <5 days after injury, ankylosing spondylitis, sepsis, and intubation.

Adult↗
PubMed1997

Bioactive labdane diterpenoids from Renealmia alpinia collected in the Suriname rainforest.

The preservation of tropical rainforests is an important goal both for the intrinsic value of their cultural and biological diversity as well as for the well-being of the peoples who make these forests their home. In addition, tropical forests are potential sources of new pharmaceutical products that can only be found by chemical prospecting in Nature's genetically encoded combinatorial library. As part of an effort to integrate biodiversity conservation and drug discovery with economic development, we have initiated a collaborative program to discover potential pharmaceuticals in the rainforest of Suriname. The plant Renealmia alpinia (Zingiberaceae) was selected for investigation based on its ethnomedical use as a febrifuge, but testing in the yeast Sc-7 assay gave a positive response, indicative of cytotoxic activity. Using this bioassay, the two new labdane diterpense, 11-hydroxy-8(17),12(E)-labdadien-15,-16-dial 11,15-hemiacetal (1) and 16-oxo-8(17),12(E)-labdadien-15-oic acid (2), and the known diterpene, 8(17),12(E)-labdadien-15,16-dial (3), have been isolated. Their structures were elucidated by 1D and 2D NMR techniques (DEPT, COSY, HETCOR, HMBC, and NOESY) and IR, UV, and MS spectra, and the absolute stereochemistry of 1 was established by CD spectroscopy and by the formation and NMR analysis of alpha-methoxyphenylacetyl esters. The hemiacetal 1 was cytotoxic to M109 cells, with an IC50 value of 2.6 micrograms/mL.

Animals↗
PubMed1997

Staffing to volume in integrated delivery networks.

If yesterday's universal staffing standards are no longer valid in today's workplace, and new standards don't seem likely in the near future, how do HIM practitioners maintain a workable staff? By embracing a detailed methodology, the author shows how it is possible to benchmark HIM staff within integrated delivery networks.

Delivery of Health Care, Integrated↗
PubMed1996

Endometrial carcinoma--relative effectiveness of adjuvant irradiation vs therapy reserved for relapse.

Fifty-four patients with recurrent endometrial carcinoma were identified from a retrospective review of charts of 304 endometrial cancer patients seen between 1983 and 1989 at our center. A review was undertaken to identify the patterns of relapse, to determine the outcome of salvage treatment, to examine the factors predictive of effective salvage, and, if salvage is effective, to assess an alternative strategy to routine adjuvant postoperative pelvic radiotherapy. Forty percent of the entire recurrent population are long-term survivors. Of the 54 relapsing patients, primary therapy had been surgery alone in 32 and surgery and adjuvant radiotherapy (rt) in 22. Isolated pelvic recurrence was the predominate relapse site in those who had not received adjuvant pelvic RT as primary therapy (23 of 32 or 72%). Distant relapse predominated in those who received adjuvant RT (17 or 22 or 77%). Twenty-eight (54%) failed in the pelvis alone, and 26 (46%) had a component of distant failure. Of the 28 with isolated pelvic relapse, 16 had vaginal mucosal disease involvement only and 12 had disease in the parametrium and/or the pelvic sidewall. With a minimum follow-up for the survivors of 5 years, 21 of the 28 with isolated pelvic relapse received radical radiotherapy and 14 or 67% had maintained pelvic control until death or last follow-up. Eleven of 14 (79%) with disease confined to the mucosa had pelvic control, whereas only 3 of 7 (43%) with extramucosal disease were controlled. No patient experienced major treatment-related toxicity. Tumor size, anatomic extent of pelvic recurrence, RT dose, and disease-free interval were examined for prognostic significance for pelvic control and survival by univariate analysis. Only anatomic extent of pelvic recurrence showed a nonstatistically significant trend as a predictor for control with P = 0.08. In conclusion, a significant proportion of patients with disease recurrence confined to the pelvis can be rendered disease-free long-term with maintained pelvic control. A reexamination of the role of routine adjuvant pelvic RT is therefore undertaken in light of these data.

Aged↗
PubMed1995

Long-term follow-up of efficacy and safety of megavoltage radiotherapy in high-risk giant cell tumors of bone.

PURPOSE: Giant cell tumors of the bone are rare and have variable presentations and natural history. There may be significant functional sequelae as a result of their locally aggressive nature or as a result of treatment. We reviewed the long-term results of radiotherapy for high risk giant cell tumors to assess: the efficacy of radiotherapy and the potential late toxicity of treatment, and to determine indications for radiation treatment. METHODS AND MATERIALS: This report is a retrospective review of 21 localized giant cell tumors of the bone treated with radiotherapy between 1959 and 1991. Radiation was used in the primary management of 13 cases and for recurrent disease in eight cases. In the primary cases, two received radiotherapy as the sole modality (including a massive pelvic lesion and an advanced maxillary sinus tumor with orbital and pterygoid invasion), and in the other 11, 3 had gross residual disease following surgery and 8 had microscopic residual disease. Of eight recurrent cases, five were treated with radiotherapy alone and three with combined surgery and radiation. Sites of origin included extremity bones in nine cases, pelvis in six, spine in four, and skull in two. Extraosseous disease was apparent in 18 tumors and extended to contiguous structures in 14 (including four cases of spinal cord compression, three cases of sacral plexopathy, and one patient with temporal lobe invasion). The most common dose regimen was 35 Gy/15 fractions/3 weeks (14 cases), with varying schedules for the remainder. RESULTS: Mean follow-up time was 15.4 years (2 to 35 years). Local control was achieved in 19 of 21 patients with radiotherapy. The two failures were subsequently salvaged for an ultimate control rate of 100%. One of the two radiotherapy failures was a marginal failure and was subsequently salvaged with combined surgery and radiotherapy. No patient died of giant cell tumor. Radiotherapy was well tolerated, with no serious late toxicity. There were no cases of malignant transformation or radiation-induced cancer. CONCLUSION: Long-term results in this series indicate that radiotherapy in modest doses (35 Gy in 15 fractions or equivalent) is a safe and effective option for primary and recurrent giant cell tumors of the bone. Radiotherapy should be used if surgery would result in significant functional morbidity and should be considered in select sites where the probability of recurrence is high and there is potential for significant morbidity from tumor relapse or subsequent surgery.

Adolescent↗
PubMed1993

The consequences of an open referral system to a community mental health service.

The first 590 patients referred to a community mental health service (the Early Intervention Service) in an inner-city district were separated into groups based on their referral source. The service has an open referral system allowing any agency (including patients) to contact the service by letter or by telephone, and priority is given to patients with serious mental illness. The results of open referral showed that the number of referrals was adequate for the service to process, the proportion of inappropriate referrals was similar in all referral agencies, and milder cases of mental illness were referred more often from doctors than from other agencies. It is concluded that an open referral system is likely to be more sensitive to need and has some advantage over closed referral arrangements in inner-city areas.

Adolescent↗
PubMed1992

EASEing in the 90s.

Explore the source record for details and available documents.

Hospitals, County↗
PubMed1991

Obstructive sleep apnoea in patients with dilated cardiomyopathy: effects of continuous positive airway pressure.

The combined effects of negative intrathoracic pressure swings during obstructive sleep apnoeas (OSAs) and increased sympathetic nervous system tone associated with hypoxia and sleep arousal may lead to pulmonary oedema or left-ventricular hypertrophy. Therefore, we have done a study of patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy to see whether OSA could contribute to impaired left-ventricular function and to assess nasal continuous positive airway pressure (NCPAP) for treatment. Eight men (aged 29-69 years) took part in the study; all were obese. Left-ventricular ejection fraction (LVEF) was measured while on stable medication and then 4 weeks after the start of nocturnal NCPAP. NCPAP was associated with abolition of OSA (mean [SE] number of apnoeas and hypopnoeas per hour of sleep 54.1 [7.2] and 1.0 [0.4] for pretreatment and NCPAP nights, respectively, p less than 0.0001). Mean (SE) LVEF increased from 37 (4)% pretreatment to 49 (5)% after four weeks' NCPAP therapy (p less than 0.0001). Withdrawal of NCPAP for 1 week in four patients was associated with a reduction in LVEF from 53 (6)% to 45 (5)% (p less than 0.001). OSA may contribute to impaired left-ventricular function in some patients with dilated cardiomyopathy of otherwise unknown origin, and reversal of OSA by NCPAP can lead to significant improvement in LVEF.

Adult↗
PubMed1985

Coping with aversive stimulation in the neonatal period: quiet sleep and plasma cortisol levels during recovery from circumcision.

Measures of behavioral state and plasma cortisol were obtained on 80 healthy, full-term, 2-3-day-old, male newborns who were scheduled to be circumcised. To establish baseline or precircumcision levels, the newborns were observed, and behavioral state was recorded for the half hour prior to circumcision. Blood was sampled via heelstick for plasma cortisol determination at the end of this observation period. The newborns were then circumcised and assigned randomly to one of 4 postcircumcision, blood-sampling time-point groups. The time points were 30, 90, 120, and 240 min following the beginning of circumcision. Behavioral state was observed during circumcision and for the half hour prior to taking the second blood sample. The results showed a return to baseline cortisol levels sometime prior to 240 min, with data from an additional group of 10 newborns indicating that the return occurred by 150 min. Behavioral distress during circumcision was associated with elevations in plasma cortisol at 30 and 90 min. Quiet sleep was correlated negatively with plasma cortisol prior to circumcision, and significant increases in quiet sleep followed circumcision, with the greatest increase corresponding to the period of most rapid reductions in cortisol.

Adaptation, Psychological↗
PubMedDate not supplied

Color flow mapping for myometrial invasion in women with a prior cesarean delivery.

OBJECTIVES: Our aim was to evaluate the utility of color flow mapping in the prediction of placental myometrial invasion in women with Cesarean delivery. METHODS: Ultrasound color flow mapping was performed on placental implantations in potential proximity to the hysterotomy scar. The smallest myometrial thickness was measured under the placenta to evaluate the degree of myometrial attenuation in this area and note was made of unusual vascular lakes. RESULTS: Two hundred fifteen women with placentas in proximity to the prior hysterotomy scar underwent color Doppler mapping. Of 20 women with placenta previa and Cesarean delivery, 15 had Cesarean hysterectomy for bleeding complications and nine had the pathological diagnosis of placental invasion. The measurement of <1 mm for the smallest myometrial thickness or presence of large intraplacental lakes was predictive of myometrial invasion (sensitivity 100%, specificity 72%, PPPV 72%, and NPV 100%). CONCLUSIONS: Color flow mapping predicted myometrial invasion when the smallest myometrial thickness was <1 mm and large intraplacental lakes were demonstrated.

Cesarean Section↗
PubMedDate not supplied

[In vitro radiosensitivity of skin fibroblasts can identify a group of patients with complications in various health tissues after radiotherapy].

PURPOSE: A retrospective study of the in vitro radiosensitivity of skin fibroblasts derived from two groups of patients treated by definitive radiotherapy for a variety of tumors who either displayed or did not display severe complications. PATIENTS AND METHODS: Seven radiotherapy patients were selected: three were treated for head and neck, prostate and non-Hodgkin lymphoma tumors, and did not develop any significant complications (control group); four patients were treated for bladder, thyroid, head and neck and anal canal tumors and developed serious acute and especially late reactions (hypersensitive group). Primary cell cultures of skin fibroblasts were established and their radiosensitivity studied by the clonogenic assay after exposing to single radiation doses ranging between 1 and 8 Gy. RESULTS: The survival fraction at 2 Gy (SF2) ranged from 0.27 to 0.38, with a mean of 0.33 for the control group, and from 0.10 to 0.20 with a mean of 0.17 for the hypersensitive group. The Mann-Whitney non-parametric test showed that the difference between the two means was statistically significant (p = 0.03). CONCLUSION: The data are in favor of a correlation between the radiosensitivity of patients' fibroblasts and the reactions of different normal tissues to radiotherapy. This association supports the use of the clonogenic survival, or a surrogate test, as a predictive assay. The multiplicity of normal tissues and organs implicated in this association suggests the existence of genetic factors that determine, at least in part, the radiosensitivity of target cells involved in the expression of normal tissues complications following radiotherapy.

Aged↗