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S Mark

Publications and source records attributed to S Mark.

16 recordsLinked to original sources
PubMed1998

Isolation and characterization of circulating 13-kDa C-terminal fragments of human insulin-like growth factor binding protein-5.

The insulin-like growth factor binding proteins (IGFBPs) are responsible for regulation of the effects and the bioavailability of the insulin-like growth factors (IGFs). We screened for circulating fragments of human IGFBP-5 in human hemofiltrate. Identification of IGFBP-5 peptides in the fractions of our peptide bank generated from hemofiltrate was performed by their immunoreactivity and their capacity to bind IGF-I. Different fragments of IGFBP-5 with molecular sizes from 12 to 25 kDa were identified. C-terminal peptides of IGFBP-5 with molecular masses of 13.3 and 13.5 kDa were purified by consecutive chromatographic steps and sequenced. Sequence analysis of the peptides revealed the (double) sequences (K)FVGGAENXAHPRII and MVPRAVYLPNXDRKG. In addition, a smaller fragment with Mr 2722 of the central IGFBP-5 region was purified and showed the sequence HTRISELKAEAVKKDRRKKLTQS (residues 121-143) indicating plasma proteolysis of IGFBP-5 C-terminal to amino acids Lys-120, Ser-143, Lys-144, and Arg-188. According to mass spectrometric and sequence analysis, Thr-152 was shown to be O-glycosylated. Fractions containing C-terminal IGFBP-5 fragments revealed significant IGF-I binding properties. Our results indicate that plasma proteolysis of IGFBP-5 preferentially occurs C-terminally to basic residues and generates different C-terminal fragments, possibly acting in an IGF-dependent manner and bearing intrinsic biological functions.

Amino Acid Sequence↗
PubMed1998

Fluorescence in situ hybridization analysis of single-cell trisomies for determination of clonality.

Conflicting data currently exist pertaining to the significance of single-cell trisomies found in a 20-cell cytogenetic analysis of hematologic malignancies. In order to determine the clonality of the numerical abnormalities found in these cases, we performed a retrospective study on a cohort of patients previously analyzed by GTG-banding at Rhode Island Hospital, from July 1, 1990 to November 30, 1996. Fluorescence in situ hybridization (FISH) was performed using chromosome enumeration probes on previously fixed bone marrow and, in some cases, peripheral blood slides from patients identified to have single-cell trisomies of selected chromosomes in 20-cell routine GTG-banded analyses. We seek to determine whether the single cell trisomies represent random nonclonal events or "the tip of an iceberg." The results of the present study indicate that a single unifying answer to the above question does not exist. While some cases are apparently random events as predicted by chance, other cases appear to represent "the tip of an iceberg." It is therefore important for cancer cytogeneticists to interpret the results of each patient on a case-by-case basis and to formulate the most optimal strategy for follow-up in the particular case under study.

Adolescent↗
PubMed1998

Sequential flow cytometry and fluorescence in situ hybridization for the study of formalin-fixed, paraffin-embedded breast cancer cells.

Both flow cytometry and fluorescence in situ hybridization (FISH) are useful techniques in the analysis of cancer tissues. When the two are used in the study of the same specimens, they are usually performed in parallel, separately. This is problematic where there is a scarcity of material, making completion of both studies impossible. Fluorescence in situ hybridization procedures that will utilize excess material discarded from flow cytometry would be advantageous. The present report describes an optimized protocol for performing sequential flow cytometry and FISH using formalin-fixed paraffin-embedded archival material. Although breast cancer tissues were used in this initial study, the protocol is applicable to other cancer tissues as well.

Breast Neoplasms↗
PubMed1998

Prebeta-1 HDL in plasma of normolipidemic individuals: influences of plasma lipoproteins, age, and gender.

Prebeta-1 HDL is a molecular species of plasma HDL of approximately 67 kDa mass that contains apolipoprotein A-I, phospholipids, and unesterified cholesterol. It participates in a cyclic process involved in the retrieval of cholesterol from peripheral tissues. In this cycle, unesterified cholesterol from cells is incorporated into prebeta-1 HDL, providing a substrate for esterification of cholesterol by lecithin:cholesterol acyltransferase. Prebeta-1 HDL then becomes incorporated into larger HDL species of alpha mobility as esterification proceeds and is regenerated during the transfer of cholesteryl esters from alpha HDL particles to acceptor lipoproteins. Thus the steady state level of prebeta-1 HDL in plasma reflects the relative efficiencies of the major metabolic processes involved in its generation and removal. We have used an isotope dilution technique to measure prebeta-1 HDL levels in the plasmas of 136 normolipidemic individuals (46 M, 90 F). The mean absolute concentration of prebeta-1 HDL as apolipoprotein A-I was 68 +/- 40 microg/ml for women, and 84 +/- 49 m/ml for men. Prebeta-1 HDL represented 5.5 +/- 3.3% of total apolipoprotein A-I in women, and 7.2 +/- 4.0% in men. The distributions of both absolute and percent prebeta-1 HDL are highly asymmetric, with skew toward higher values. However, the skew appears not to be attributable to either plasma cholesterol or triglyceride levels which are also skewed in population samples. The percent prebeta-1 HDL was negatively correlated with HDL cholesterol levels (P < 0.0001), whereas absolute levels of prebeta-1 HDL were positively correlated with apolipoprotein A-I and negatively correlated with HDL cholesterol (P, for both, < 0.0001). Multiple linear regression analysis revealed effects of age and gender, but no association with lipoprotein fractions other than HDL. Lower levels of prebeta-1 HDL were associated with female gender in all models.

Adolescent↗
PubMed1995

Comparison of Diskus inhaler, a new multidose powder inhaler, with Diskhaler inhaler for the delivery of salmeterol to asthmatic patients. Canadian Study Group.

Administration of the long-acting beta 2-adrenoceptor agonist salmeterol from a new, easy-to-operate, multidose powder inhaler (Diskus) containing 60 sealed doses in a foil strip has been compared with administration from a Diskhaler inhaler in a multicenter, double-blind, double-dummy, parallel-group study. Asthmatic patients taking anti-inflammatory treatment, with baseline FEV1 > or = 60% and < or = 90% predicted were treated for 4 weeks with salmeterol 50 micrograms twice daily from either the Diskus or Diskhaler inhaler. The two treatments were equivalent (90% CLs for the difference in mean morning PEFR: -2.2, 8.7 L/min). The Diskus inhaler was rated easier to use and was preferred by more patients than the Diskhaler inhaler (73% vs. 15%).

Adolescent↗
PubMed1994

Premenopausal bone loss and depot medroxyprogesterone acetate administration.

A 39-year-old woman on depot medroxyprogesterone acetate for 17 years developed multiple fractures after falling from a stationary horse. Densitometry revealed significant osteopenia. Although the reported patient was a thin, Caucasian woman, she did not have any other significant risk factors for osteoporosis except for a possible state of partial estrogen deficiency induced by the use of depot medroxyprogesterone acetate. Studies have shown that the estradiol levels of premenopausal women who have received this hormonal contraceptive for more than 1 year never reach those seen in the mid-cycle or luteal phase of the normal menstrual cycle. The estradiol levels are comparable only with those found in the early follicular phase. Therefore, women who use depot medroxyprogesterone acetate are in a state of partial estrogen deficiency, which may be associated with increased bone loss.

Adult↗
PubMed1994

Synchronous management of anastomotic contracture and stress urinary incontinence following radical prostatectomy.

Of 77 patients presenting for artificial urinary sphincter implantation due to incontinence following radical prostatectomy 26 had a significant associated urethrovesical anastomotic contracture. Synchronous endoscopic contracture incision with electrocautery and implantation of an artificial urinary sphincter (AMS800) were performed in all cases. A total of 25 patients void with a good subjective flow, with an average followup of 32 months. In 1 patient symptomatic stenosis recurred 6 months after incision and reincision was successful at the time of sphincter revision. No infection or erosion developed and 24 patients are socially continent (0 to 1 thin pad per day). During this time 5 patients underwent 8 revisions of the artificial sphincter. Synchronous contracture incision with electrocautery and artificial urinary sphincter implantation are safe and provide satisfying results in patients with complex post-prostatectomy incontinence.

Anastomosis, Surgical↗
PubMed1994

A virilized patient with congenital hemihypertrophy.

An 18 year old woman with congenital hemihypertrophy of her left side, presented with the rapid onset of virilism, hypertension and a cushingoid appearance. A computed tomographic examination revealed adrenal and hepatic masses. Adrenocortical carcinoma was confirmed by surgical pathology. Hemihypertrophy is linked to a variety of benign and malignant disorders that usually appear during childhood. These disorders include adrenocortical carcinoma and hepatoblastoma. We bring this case to clinical attention to increase awareness that adult patients with congenital hemihypertrophy are still at a significant risk of developing neoplasms.

Adolescent↗
PubMed1988

Bulimia in obese individuals. Relationship to normal-weight bulimia.

We compared 23 obese subjects meeting DSM-III criteria for bulimia with 47 obese nonbulimic subjects and 47 normal-weight bulimic subjects using structured diagnostic interviews. The obese bulimic subjects were similar to the normal-weight bulimic subjects but different from the nonbulimic obese subjects in exhibiting a high lifetime rate of major affective disorder. However, the obese bulimic subjects were much less likely than the normal-weight bulimic subjects to use self-induced vomiting as a method of purging. These results suggest that obese individuals with bulimic symptoms may constitute a sizable but little-recognized population. Further studies will be required, however, to assess whether the syndrome of bulimia in obesity represents a valid diagnostic entity.

Adult↗
PubMed1987

Varicella zoster antibody testing in the care of pregnant women exposed to varicella.

Appropriate use of varicella zoster immunoglobulin to prevent or ameliorate maternal or perinatal infection depends on accurate identification of varicella-susceptible women. Detection of fluorescent antibody to varicella zoster virus membrane antigen is an available means for identifying women exposed to varicella who are at risk for infection. During a 5 1/2-year period, 37 pregnant women who had been exposed to varicella and who had a negative or indeterminate history of prior varicella were tested for the presence of varicella zoster virus membrane antigen. Among the 17 women with a negative history, 12 (71%) had a positive test result and five (29%) had a negative test result. Among 20 women with undeterminant histories, 18 (90%) were immune and two (10%) were susceptible. Three additional women who were tested despite a history of varicella had positive varicella zoster virus membrane antigen test results. Overall, 81% of patients with a negative or uncertain history of varicella had serologic evidence of past varicella. One of six untreated seronegative women and one weakly positive woman developed disease. There was no instance of congenital varicella. Expeditious determination of varicella zoster virus membrane antigen or equivalent anti-varicella antibody status in pregnant women exposed to varicella appears to be a rapid, satisfactory method for determining who should promptly receive varicella zoster immunoglobulin passive immunization.

Antigens, Surface↗
PubMed1987

High resolution MR imaging of peripheral joints using a quadrature coil at 0.35 T.

The utility of a specially dedicated quadrature detection (QD) mode limb coil for the MR evaluation of peripheral joints has been evaluated. High resolution images of the knee, elbow, wrist and ankle provided excellent anatomical delineation of the cortical and medullary bone, cartilage, ligaments and menisci over a homogeneous field of view. Pathological conditions including meniscal injury, fracture and osteonecrosis were accurately detected. The QD limb coil can be advantageously used for the MR evaluation of peripheral joints at an intermediate field strength.

Evaluation Studies as Topic↗
PubMedDate not supplied

[The fat ration for the premature infant].

The authors studied cantitative and calitative fat dietary intake in conditions of isocaloric energetic diets and effects on somatic development and on plasma levels of fats in 3 randomized populations of premature infants. They concluded that dietary intake of 3-6.4 g fats/kg b.w./24 hours permitted a satisfactory somatic development (weight, height, cranial circumference). In conditions of isocaloric energetic diets, levels of fat intake of 3g/kg b.w./24 hours delivered only the energy for proteic syntheses and levels of 5.6-6.4 g/kg b.w./24 hours also permitted the constitution of body deposits. The levels of total lipids and cholesterol were related to the dietary intake of fats. In case of dietary supplementation of linoleic acid, the plasma levels of cholesterol were reduced and the plasma levels of HDL were augmented.

Birth Weight↗
PubMedDate not supplied

Hypercalcaemia in an immobilised patient with pneumonia.

Hypercalcaemia is a serious complication of sepsis and prolonged immobility. Hormonal, humoral and mechanical factors play a complex role in its development. Because hypercalcaemia is associated with a significant increase in morbidity and mortality, early treatment is recommended. Pamidronate is an effective pharmacological agent and should be considered as primary therapy for this syndrome.

Diphosphonates↗