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L Kessler

Publications and source records attributed to L Kessler.

At least 19 recordsLinked to original sources
PubMed1999

Early introduction of solid foods among urban African-American participants in WIC.

OBJECTIVE: To compare infant feeding practices among low-income, urban, African-American women enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) with current recommendations for infant feeding. DESIGN: Longitudinal follow-up of women and their infants who participated in a WIC-based breast-feeding promotion project. Women enrolled prenatally at or before 24 weeks of gestation were followed up until 16 weeks postpartum. SUBJECTS/SETTING: Two hundred seventeen African-American WIC participants in an urban area. METHODS: Data related to infant feeding practices were collected by interviewers who used a structured questionnaire to determine when nonmilk liquids or solids were introduced to the infant. Reported practices were compared with current recommendations. STATISTICAL ANALYSIS PERFORMED: Contingency table analysis, including chi 2 tests, and multivariate analysis using logistic regression. RESULTS: By 7 to 10 days postpartum, approximately a third of infants were receiving some nonmilk liquids or solids; this escalated to 77% by 8 weeks and 93% by 16 weeks postpartum. Women breast-feeding exclusively (i.e., not adding nonmilk liquids or solids) were least likely, and women providing mixed feeding (breast milk and formula) were more likely, than women feeding formula exclusively to introduce nonmilk liquids and solids at each data collection time period. APPLICATIONS/CONCLUSIONS: WIC participants who receive instruction about infant feeding nutrition are no more likely than mothers who do not participate in WIC to follow infant feeding guidelines recommended by the American Academy of Pediatrics in regard to the time when solids should be introduced to infants' diet. Our findings suggest the need for WIC to implement more powerful and innovative educational and motivational strategies to help mothers delay the introduction of nonmilk liquids and solid foods until their infants are 4 to 6 months old, as recommended.

Black or African American↗
PubMed1998

Technology assessment of medical devices at the Center for Devices and Radiological Health.

We reviewed the Food and Drug Administration's regulatory process for medical devices and described the issues that arise in assessing device safety and effectiveness during the postmarket period. The Center for Devices and Radiological Health (CDRH), an organization within the Food and Drug Administration, has the legal authority and responsibility for ensuring that medical devices marketed in the United States are both reasonably safe and effective for their intended use. This is an enormous challenge given the diversity of medical devices and the large number of different types of devices on the market. Many scientific and regulatory activities are necessary to ensure device safety and effectiveness, including technology assessment, albeit in a manner quite different from that of conventional technology assessment. The basic approach taken at the CDRH to ensure device safety and effectiveness is to develop an understanding of the way in which a medical device works and how it will perform in clinical situations.

Device Approval↗
PubMed1998

A small, nonpeptidyl mimic of granulocyte-colony-stimulating factor [see commetns].

A nonpeptidyl small molecule SB 247464, capable of activating granulocyte-colony-stimulating factor (G-CSF) signal transduction pathways, was identified in a high-throughput assay in cultured cells. Like G-CSF, SB 247464 induced tyrosine phosphorylation of multiple signaling proteins and stimulated primary murine bone marrow cells to form granulocytic colonies in vitro. It also elevated peripheral blood neutrophil counts in mice. The extracellular domain of the murine G-CSF receptor was required for the activity of SB 247464, suggesting that the compound acts by oligomerizing receptor chains. The results indicate that a small molecule can activate a receptor that normally binds a relatively large protein ligand.

Animals↗
PubMed1998

WIC-based interventions to promote breastfeeding among African-American Women in Baltimore: effects on breastfeeding initiation and continuation.

We evaluated the single and combined effects of introducing a motivational video and peer counseling into four matched WIC clinics on breastfeeding initiation and continuation at 7-10 days among African-American WIC participants. Of the 242 women with complete data, 48% initiated breastfeeding, but only 31% were still breastfeeding at 7-10 days. Initiation was associated with cesarean delivery, infant feeding instruction, no artificial milk discharge pack, attending the peer counselor only-intervention site, and intention to breastfeed. Continuation was influenced by infant feeding instruction, no artificial milk discharge pack, and intention to breastfeed. Overall, trends toward a positive impact of the breastfeeding promotion activities were evident but weak, and largely gone by 7-10 days postpartum.

Adolescent↗
PubMed1998

Medical coverage for local national employees in the Czech Republic, Hungary, Poland and Russia.

Employers that must provide medical benefits for employees in Russia and other Eastern European countries cannot try to match the coverage they provide in the United States. This article, which focuses on the Czech Republic, Hungary, Poland and Russia, summarizes the medical benefits provided by each government's social security system, describes other means of accessing medical care in these countries and outlines the insured supplemental benefit plans that may be available to employers in the local market.

Attitude↗
PubMed1998

Possible involvement of Von Willebrand factor in pancreatic graft thrombosis after kidney-pancreas transplantation: a retrospective study.

Early postoperative graft thrombosis remains the second cause of failure in pancreas transplantation. Thus, the aim of this study was to compare retrospectively coagulation and fibrinolysis in type I diabetic recipients of simultaneous kidney pancreas transplants having or not experienced thrombosis of their pancreatic graft. From December 1990 to August 1996, 30 simultaneous kidney pancreas transplants were performed in 30 uremic type I diabetic patients. Acute thrombosis of the pancreatic graft was observed among 6 patients (group A), whereas 24 did not develop thrombosis (group B) although 4 died from other causes. The control groups were composed of kidney transplant (group C) or haemodialysed (group D) non-diabetic patients, type I diabetics with HbA1C < 8% (group E) or > or = 8% (group F) who were not in end-stage renal failure and kidney transplant type I diabetic patients (group G). Beginning at least 6 months after transplantation, we analysed hemostatic factors (fibrinogen, thrombin, and prothrombin times), coagulation inhibitors (proteins C and S), fibrinolysis (plasminogen activator inhibitor) and endothelial cell abnormalities (Von Willebrand factor: VWf). Micro and macrovascular complications were evaluated on a score ranging from 0 to 12. Hemostatic factors, coagulation inhibitors and fibrinolysis were similar in groups A and B whereas VWf differed significantly in group A (3.49 +/- 0.93 IU/ml) as compared to group B (2.04 +/- 0.92 IU/ml) (p < 0.05). VWf was also significantly increased in group A relative to the control groups C, D, E, F, and G. The score of vascular complications was increased in groups A and B and significantly higher in group A (9 +/- 0.81 vs. 6.07 +/- 1.75) (p < 0.01), while a correlation (r = 0.812, p > 0.05) was observed between VWf levels and the severity of vascular complications. These results point out the possible involvement of VWf in the pathogenesis of pancreatic vein thrombosis in kidney-pancreas transplantation.

Adult↗
PubMed1998

Von Willebrand factor in diabetic angiopathy.

Diabetes mellitus is a complex disease characterised by chronic hyperglycaemia responsible for complications affecting the kidneys, eyes, peripheral nerves and micro- and macrovascular systems. Von Willebrand factor (vWf), a multimeric glycoprotein mainly synthesised by endothelial cells, is involved in platelet adhesion and aggregation and acts as the carrier of coagulation factor VIII in plasma. Increased levels of vWf, reflecting activation of or damage to endothelial cells, have been described in association with atherosclerosis and diabetes. vWf appears to be a predictive marker of diabetic nephropathy and neuropathy, although not of retinopathy, which suggests that endothelial dysfunction precedes the onset of diabetic microangiopathy. This dysfunction could be especially involved in the pathogenesis of renal abnormalities of diabetes. vWf is not a predictive marker of macroangiopathy when diabetes is associated with atherosclerotic risk factors. In the presence of chronic diabetic complications, vWf levels are not associated with any grade of retinopathy but increase with the severity of nephropathy and would appear to be a risk factor for macrovascular mortality in these patients. The endothelial dysfunction of diabetes can generate atherosclerotic lesions responsible for damage to the arterial wall, atheroma and formation of platelet microaggregates. Concomitant with high vWf levels, other possible mechanisms of endothelial damage include reduced synthesis or release of nitric oxide, hyperglycaemic pseudohypoxia and protein kinase-C activation, increased synthesis of proteins bearing advanced glycosylation end-products or transforming growth factor-beta (TGF-beta) activation of coagulation and inhibition of fibrinolysis. At present, it is not known whether high vWf levels are inherent to the physiopathology of diabetes, nor whether diabetes induces endothelial dysfunction through other pathways. However, since angiopathy resulting from endothelial dysfunction is the main cause of morbidity and mortality in diabetic patients, appropriate therapy is necessary to reduce these complications. Glycaemic control seems to be insufficient to normalise plasma vWf, whereas a decrease can be obtained by ingestion of diets rich in oleic acid or by treatment with statins. Inhibition of the binding of vWf to the GPlba receptor by synthetic peptides, aurin tricarboxylic acid or monoclonal antibodies has been proposed to prevent the thrombosis induced by high levels of plasma vWf. Thus, vWf probably represents an interesting target for the inhibition of thrombosis in diabetes.

Arteriosclerosis↗
PubMed1997

Influence of acinar tissue contamination on encapsulated pancreatic islets: morphological and functional studies.

BACKGROUND: The present study concerns the influence of acinar contamination on pancreatic islets encapsulated in an artificial membrane (AN 69). METHODS: Pure, handpicked pancreatic islets were contaminated by the addition of acinar tissue (ratio, 1:1). The morphological aspect and insulin release of both pure (n=12) and contaminated (n=12) encapsulated islets were assessed after 10 days of culture or implantation in the peritoneal cavity of rats. RESULTS: After implantation, the encapsulated islets, irrespective of their purity, were totally altered, whereas the morphological aspect of the cultivated islets remained intact only in the absence of acinar tissue contamination. This contamination induced a significant decrease in the stimulation index of insulin release. The stimulation index decreased by 42% for fresh islets and by 52% and 34% for cultivated and implanted islets, respectively, without modification in their basal release of insulin. CONCLUSIONS: The acinar tissue proved detrimental to the encapsulated implanted and cultivated islets.

Animals↗
PubMed1997

Physicochemical and biological studies of corona-treated artificial membranes used for pancreatic islets encapsulation: mechanism of diffusion and interface modification.

The artificial AN69 membrane (Hospal), a synthetic copolymer composed of acrylonitrile and sodium methallyl sulphonate suitable for pancreatic islet encapsulation, was submitted to physicochemical treatment (Corona discharge) to improve its insulin permeability. X-ray photoelectron spectroscopy (XPS) analysis of the AN69 membrane indicated the presence of up to two molecular layers of glycerol at its surface while the surface energies revealed the presence of hydrophilic sites (-SO3Na/glycerol) located at the membrane surface and acrylonitrile hydrophobic groups inside the material. The Corona discharges decreased the number of glycerol molecules at the membrane surface and from a biological point of view, produced a threefold increase in insulin diffusion. Furthermore, the biocompatibility of the treated membrane was preserved after 1 year of intraperitoneal implantation. The increase in insulin permeability should result from a decrease of the membrane polarity and of a steric hindrance in pores. Thus, Corona discharge treatment may serve to optimize the properties of artificial membranes used for pancreatic islets encapsulation.

Animals↗
PubMed1997

One-stage surgery with a nonsubmerged implant system.

Although nonsubmerged implant surgery can reduce patient trauma and costs by eliminating the uncovering procedure, one-piece implants cannot be shortened for esthetic results. However, a new implant design that comes preattached on a multipurpose collar is used for insertion, nonsubmerged healing, and as an abutment base. For submucosal margins, the collar can be replaced by an esthetic abutment that connects directly to the implant. Surface treatments include midsections roughened by hydroxyapatite or titanium plasma spray coatings, with smoother, acid-etched necks and self-tapping apical ends. Screw-retained, friction-fit abutments offer prosthodontic stability and uniformity, despite the submucosal implant type.

Dental Abutments↗
PubMed1996

A drumstick?

Explore the source record for details and available documents.

AIDS-Related Opportunistic Infections↗
PubMed1996

Screening for Wilms' tumor in children with high-risk congenital syndromes: considerations for an intervention trial.

Screening for cancer in children is uncommon. However, in children with congenital syndromes associated with Wilms' tumor, conditions exist that potentially make screening effective. This select population of children 1) are relatively easily identified; 2) have a high incidence of Wilms' tumor; 3) if identified before development of Wilms' tumor, may have a decrement in morbidity/mortality; and 4) are amenable to a simple and acceptable screening technology, renal sonography exams. Many clinicians have recommended screening for cancer in children with congenital syndromes associated with Wilms' tumor. However, neither costs nor effectiveness of such recommendations have been evaluated systematically. The strongest evidence for or against Wilms' tumor screening in this select population would be provided by a randomized screening trial. Prior to undertaking such a trial, the key parameters that dominate the cost and effectiveness of screening should be identified. Simulation models, such as cost effectiveness analysis, offer a starting point for deciding whether cancer screening is appropriate, and if so, under what set of conditions. We review basic conditions required for a successful screening trial in children with syndromes that are at increased risk of Wilms' tumor. We also discuss the use of cost-effectiveness analysis as a preliminary step in determining the feasibility of an intervention trial.

Child↗
PubMed1996

Cytotoxicity of peritoneal murine macrophages against encapsulated pancreatic rat islets: in vivo and in vitro studies.

The aim of this work was to study in vivo and in vitro the involvement of macrophages and interleukin-1beta (IL-1beta) in the necrosis of encapsulated islets during xenograft and to evaluate the immunoprotective efficiency of the AN69 membrane. In vivo, 6 days after implantation, 65% of the membrane surface of the devices containing the islets was colonized with macrophages compared with only 5% of the surface of the empty control devices. The morphological aspect of implanted islets was altered and their insulin release decreased significantly compared with freshly isolated ones (265 +/- 50 vs. 507 +/- 81 microU/mL). In vitro, the insulin release of encapsulated islets cultured for 2 days decreased to 32 and 28%, respectively, in the presence of IL-1beta and macrophages. The addition of anti-IL-1beta antibody to the co-culture of macrophages and islets did not modify this loss of functional activity. Furthermore, IL-1beta passed through the AN69 membrane. In conclusion, macrophages are involved in damaging encapsulated pancreatic islets and are probably partly responsible for islet transplantation failure.

Animals↗
PubMed1996

[Benefits and limitations of pancreas transplantation in insulin-dependent diabetics: a study apropos of 26 patients].

From November 1990 to March 1995, 26 simultaneous pancreas-kidney (SPK) transplants were carried out. The recipients were uremic type I diabetic patients. After the first year of transplantation, patient survival was 96% and pancreas and kidney survival was 69% and 84%, respectively. The pancreas transplant failure was due to veinous thrombosis (two cases), and to graft rejection (71%). The most common urologic complications of bladder drainage were urethritis (61%), bicarbonate loss (42%) and urinary tract infections (100%). Fasting blood glucose (0.91 +/- 0.1 g/L), hemoglobin A1C (5.3 +/- 0.4%) and lipidic profile were found to be normal among diabetic recipients whose grafts had been functioning for 1 year. The insulin secretion of type I diabetic patients with SPK transplants (n = 13), and six non diabetic patients with kidney transplants was assessed by oral glucose tolerance tests. Only the patients with SPK transplants presented late hyperinsulinemia at 120 minutes. The quality of life for both type I diabetic patients after SPK transplants and diabetics treated by insulinotherapy (n = 6), was studied. After transplantation, the quality of life improved only because of insulin independence. In spite of chirurgical and urologic complications, pancreas transplantation in type I diabetic patients improves both metabolic control and quality of life.

Adult↗
PubMed1996

Nasopharyngeal carcinoma: an EBV-associated tumour not significantly influenced by HIV-induced immunosuppression. The AIDS/Cancer Working Group.

We used a link between cancer (859,398 reports) and AIDS (50,050 reports) registries in the United States to study whether nasopharyngeal carcinoma (NPC) was increased in the population with AIDS. There was no indication of a significantly increased risk up to or after the AIDS diagnosis, which argues against progressively failing immunity being important in the development of this malignancy.

Adult↗
PubMed1996

Pancreatic islet macroencapsulation: a new device for the evaluation of artificial membrane.

We propose a new device especially designed to test membranes for islet macroencapsulation. It is composed of three independent parts: a support made of three polytetrafluoroethylene rings, the membrane that forms the walls of the encapsulation chamber, and a collagen gel that immobilizes the islets. Studies of this device were performed with the AN69 membrane. After 2 months of implantation in the peritoneal cavity of rats, the empty device was found to be biocompatible, referred to as weak cellular adhesion. In vitro the encapsulation preserved the peak of insulin release in response to high glucose during a perifusion test (0.36 +/- 0.02 microU/ml/islet for free or encapsulated islets). As a result of the collagen gel, the morphological aspect and functional activity were still preserved after 7 days of culture. In vivo xenotransplantation into diabetic mice normalized the fasting glycemia up to 30 days. Numerous macrophages adhered to the outer surface of the membrane, and a layer of cells emerging from the destruction of islets covered the inner surface. In addition, the morphological aspect of many islets was altered. By showing that the AN69 membrane was only partially efficient for islet xenotransplantation, this new device proved to be of interest for testing a variety of membranes.

Acrylic Resins↗