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Biomedical subjects

L Martin

Publications and source records attributed to L Martin.

At least 109 records · Page 6Linked to original sources
PubMed2001

Cytohistological correlation of abnormal cervical lesions in Native American females in Mississippi.

Earlier studies have reported that cervical cancer mortality and incidence rates in Native American women are one of the highest in the United States. In recent years, the rate of abnormal cervical lesions in this group has been a public health concern. The objective of this study was to evaluate a cytohistologic correlation of abnormal cervical lesions in Native American women in Mississippi. The cytohistologic results from 77 Native American women with an abnormal diagnosis were reported to the University of Mississippi Medical Center during 1993-1996. The cases were divided into four groups; which included 7(9%) atypical squamous cells of undetermined significance (ASCUS), 51(66%) low-grade squamous intraepithelial lesions (LGSIL), 19(25%) high-grade squamous intraepithelial lesions (HGSIL), and no invasive carcinomas. Out of the study cases, 57 women presented with an abnormal gynecological history. The mean age was 29.97 years with a range of 14 to 87. The results were tallied and evaluated using SPSS. Only, 57 cases had a histologic evaluation, with an overall correlation rate of 84% (48/57). The histopathologic diagnosis confirmed 12 negative, 26 CIN I, 17 CIN II/CIN III, and 2 invasive carcinomas. The results of this study conclude that cervical intraepithelial lesions are significant among Native American women in Mississippi. Fifty-six (98%) of the patients with histologic evaluations presented with an abnormal gynecologic history; therefore, education and routine cytologic screening is imperative for the detection of cervical cancer in high-risk groups.

Adolescent↗
PubMed2001

[Paraneoplastic pemphigus: a pustular form during chronic lymphoid leukemia].

BACKGROUND: Paraneoplastic pemphigus is an autoimmune disease of the skin and mucosa described in 1990. The condition is generally associated with lymphoma or chronic lymphoid leukemia. Lesions are often misleading, masquerading as polymorphous erythema or lichen. We report a case of paraneoplastic pemphigus with pustulous skin lesions. CASE REPORT: A 52-year-old man developed over a few weeks time erosive lesions of the oral cavity and lips associated with papulous skin lesions. Secondarily, large-sized pustules, sometimes a hypopion, were observed associated with bullae. The diagnosis of paraneoplastic pemphigus was confirmed by direct immunofluorescence that evidenced IgG deposits within the keratinocytes and along the basal membrane and by indirect immunofluorescence on rat bladder that evidenced circulating antibodies. This paraneoplastic pemphigus was the inaugural sign of chronic lymphoid leukemia. DISCUSSION: Skin lesions described in paraneoplastic pemphigus include: erosion, vesicles, bullae, and psoriasiform, lichen-like, plate-like or vegetative formations. To our knowledge, this is the first report of a pustulous form; clinically similar to Hallopeau pustulous pemphigus.

Anti-Inflammatory Agents↗
PubMed2001

[Multiple skin and mouth squamous cell carcinomas related to long-term treatment with hydroxyurea].

INTRODUCTION: Cutaneous side-effects of hydroxyurea treatment are frequently observed. Squamous cell carcinomas are the most severe among them. We report a patient with skin and mouth carcinomas after hydroxyurea treatment. To the best of our knowledge, this is the first case reported. OBSERVATION: A 83-year-old woman had been treated with hydroxyurea from 1985 to 1998 for polycythemia vera. She was referred to our institution in 1998 for painful erosions of both hands. Clinical examination revealed a squamous cell carcinoma leading to amputation of a finger. Hydroxyurea was stopped at this time, and the patient underwent treatment with pipobroman. From May 1998 to March 2000, the patient developed numerous skin keratoses and four squamous cell carcinomas on both hands. In September 2000 and October 2000, two additional skin carcinomas and two mouth carcinomas were diagnosed. DISCUSSION: Cutaneous carcinomas are severe side effects of hydroxyurea therapy. They usually occur after several years of treatment and their outcome may be lethal. The chronology and clinical signs are in favour of implicating hydroxyurea in the development of skin and mouth carcinomas. Despite a bibliographic research using Medline and Embase data bases, we could not find another case-report with simultaneous occurrence of skin and mouth carcinomas after hydroxyurea therapy. This observation emphasizes the need of a long term follow-up in patients receiving hydroxyurea.

Aged↗
PubMed2001

[Fatal toxic respiratory epitheliolysis. Subacute tracheo-bronchial desquamation in Stevens-Johnson syndrome].

Acute bronchial mucosal sloughing related to Toxic Epidermal Necrolysis (Lyell syndrome) is widely reported in literature. On the contrary severe respiratory involvement is rare in post-infectious or toxic Epitheliolysis (Stevens-Johnson syndrome). There is no well-known predictive sign of bronchial epithelium involvement. An 18-year-old patient was admitted for Stevens-Johnson syndrome related to sulfasalazine (salazosulfapyridine). There were no respiratory signs. An acute respiratory failure occurred 36 hours after from admission due to an obstructive and desquamative necrosis of the tracheobronchial epithelium. We purpose that a fiberoptic laryngoscopy should be performed even in non-dyspneic patients suffering from Stevens-Johnson syndrome if hypersecretion is present. Fiberoptic bronchoscopy can be helpful in these cases.

Acute Disease↗
PubMed2000

Quantitative trait loci on chromosomes 3 and 17 influence phenotypes of the metabolic syndrome.

Recent research has emphasized the importance of the metabolic cluster, which includes glucose intolerance, dyslipidemia, and high blood pressure, as a strong predictor of the obesity-related morbidities and premature mortality. Fundamental to this association, commonly referred to as the metabolic syndrome, is the close interaction between abdominal fat patterning, total body adiposity, and insulin resistance. As the initial step in identifying major genetic loci influencing these phenotypes, we performed a genomewide scan by using a 10-centiMorgan map in 2,209 individuals distributed over 507 nuclear Caucasian families. Pedigree-based analysis using a variance components linkage model demonstrated a quantitative trait locus (QTL) on chromosome 3 (3q27) strongly linked to six traits representing these fundamental phenotypes [logarithm of odds (lod) scores ranged from 2.4 to 3.5]. This QTL exhibited possible epistatic interaction with a second QTL on chromosome 17 (17p12) strongly linked to plasma leptin levels (lod = 5.0). Situated at these epistatic QTLs are candidate genes likely to influence two biologic precursor pathways of the metabolic syndrome.

Blood Glucose↗
PubMed2000

"Open" structures of MurD: domain movements and structural similarities with folylpolyglutamate synthetase.

UDP-N-acetylmuramoyl-l-alanine:d-glutamate (MurD) ligase catalyses the addition of d-glutamate to the nucleotide precursor UDP-N-acetylmuramoyl-l-alanine (UMA). The crystal structures of Escherichia coli in the substrate-free form and MurD complexed with UMA have been determined at 2.4 A and 1.88 A resolution, respectively. The MurD structure comprises three domains each of a topology reminiscent of nucleotide-binding folds. In the two structures the C-terminal domain undergoes a large rigid-body rotation away from the N-terminal and central domains. These two "open" structures were compared with the four published "closed" structures of MurD. In addition the comparison reveals which regions are affected by the binding of UMA, ATP and d-Glu. Also we compare and discuss two structurally characterized enzymes which belong to the same ligase superfamily: MurD and folylpolyglutamate synthetase (FGS). The analysis allows the identification of key residues involved in the reaction mechanism of FGS. The determination of the two "open" conformation structures represents a new step towards the complete elucidation of the enzymatic mechanism of the MurD ligase.

Adenosine Triphosphate↗
PubMed2000

Differences in the contents of total sugars, reducing sugars, starch and sucrose in embryogenic and non-embryogenic calli from Medicago arborea L.

The total sugars, reducing sugars, starch and sucrose in embryogenic and non-embryogenic calli from explants (cotyledons, petioles, hypocotyls and leaves) obtained from Medicago arborea L. seedlings were evaluated. Total sugars were the major components in the calli and no significant differences between embryogenic and non-embryogenic calli were observed. In contrast, important differences between the embryogenic and non-embryogenic calli were observed for reducing sugars, the highest levels being observed in embryogenic calli. The highest starch levels were found in non-embryogenic calli developed in MS medium. During the development of somatic embryogenesis very low starch levels in the callus were found. During the first months of culture, no significant differences in the sucrose content were found between calli that produced embryos and those that did not. The most important differences in sucrose were seen between calli transferred to medium F0, which had the greatest embryogenic capacity, and those transferred to medium F6, which inhibited embryogenesis. In the latter case, an increase in sucrose was observed.

Journal Article↗
PubMed2000

Genetic manipulation of the rabbit heart via transgenesis.

BACKGROUND: Transgenesis using cardiac-specific expression has been valuable in exploring cardiac structure-function relationships. To date, cardiac-selective studies have been confined to the mouse. However, the utility of the mouse is limited in certain, possibly critical, aspects with respect to cardiovascular function. METHODS AND RESULTS: To establish the potential validity of transgenic methodology for remodeling a larger mammalian heart, we explored cardiac-selective expression in transgenic rabbits. The murine alpha- and beta-cardiac myosin heavy chain gene promoters were used to express a reporter gene, and transgene expression was quantified in cardiac, skeletal, and smooth muscles as well as in nonmuscle tissues. Although neither promoter exactly mimics endogenous patterns of myosin heavy chain expression, both are able to drive high levels of transgene expression in the cardiac compartment. Neither promoter is active in smooth muscle or nonmuscle tissues. CONCLUSIONS: Directed organ-specific expression is feasible in a larger animal with existing reagents, and cardiac-selective transgenic manipulation is possible in the rabbit.

Animals↗
PubMed2000

RANK is the intrinsic hematopoietic cell surface receptor that controls osteoclastogenesis and regulation of bone mass and calcium metabolism.

We have generated RANK (receptor activator of NF-kappaB) nullizygous mice to determine the molecular genetic interactions between osteoprotegerin, osteoprotegerin ligand, and RANK during bone resorption and remodeling processes. RANK(-/-) mice lack osteoclasts and have a profound defect in bone resorption and remodeling and in the development of the cartilaginous growth plates of endochondral bone. The osteopetrosis observed in these mice can be reversed by transplantation of bone marrow from rag1(-/-) (recombinase activating gene 1) mice, indicating that RANK(-/-) mice have an intrinsic defect in osteoclast function. Calciotropic hormones and proresorptive cytokines that are known to induce bone resorption in mice and human were administered to RANK(-/-) mice without inducing hypercalcemia, although tumor necrosis factor alpha treatment leads to the rare appearance of osteoclast-like cells near the site of injection. Osteoclastogenesis can be initiated in RANK(-/-) mice by transfer of the RANK cDNA back into hematopoietic precursors, suggesting a means to critically evaluate RANK structural features required for bone resorption. Together these data indicate that RANK is the intrinsic cell surface determinant that mediates osteoprotegerin ligand effects on bone resorption and remodeling as well as the physiological and pathological effects of calciotropic hormones and proresorptive cytokines.

Animals↗
PubMed2000

Feeding schedules in hospitals for newborn infants.

BACKGROUND: Regular breastfeeding times have been thought to help establish routines and promote infant digestion, while frequent breastfeeding has been recommended to enhance breastfeeding and infant growth. OBJECTIVES: The objective of this review was to assess the effects of frequent breastfeeding compared with less frequent breastfeeding in the early days after birth. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing on demand or frequent breastfeeding (two or three hourly) schedules in hospital compared with four hourly restricted feeds. DATA COLLECTION AND ANALYSIS: Trial quality was assessed and data were extracted independently by two reviewers. MAIN RESULTS: Three trials involving 400 women were included. There were significant methodological limitations in some of the studies. Compared to two hourly, three hourly or on demand breastfeeding, restricted (less frequent four hourly breastfeeding) was associated with greater discontinuation of breastfeeding by four to six weeks postpartum (relative risk 1.53, 95% confidence interval 1.08 to 2.15). Restricted breastfeeding was associated with increased incidence of sore nipples (relative risk 2.12, 95% confidence interval 1.22 to 3.68), engorgement (relative risk 2.10, 95% confidence interval 1.25 to 3.21) and the need to give additional (formula) feeds (relative risk 3.14, 95% 1.24 to 8.00). REVIEWER'S CONCLUSIONS: There appear to be a number of disadvantages from restricting breastfeeding to a four hourly schedule in the first few days after birth. More frequent or on demand breastfeeding is associated with fewer complications and longer duration of breastfeeding.

Breast Feeding↗
PubMed2000

Interventions for influencing sleep patterns in exclusively breastfed infants.

BACKGROUND: The difference between night and day may be reinforced in young babies by offering a 'focal feed' between 10pm and midnight and gradually lengthening the intervals between night-time feeds by a variety of other activities (such as nappy changing, re-swaddling and walking with the infant). OBJECTIVES: The objective of this review was to assess the effects of using a structured training programme to teach exclusively breastfed infants to sleep through the night by eight weeks old. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. SELECTION CRITERIA: Acceptably controlled trials of a structured programme accentuating the difference between night and day compared with no intervention in first time parents of singleton babies, with mothers intending to exclusively breastfeed their infants for at least eight weeks post-partum. DATA COLLECTION AND ANALYSIS: Trial quality was assessed and data were extracted independently by two reviewers. MAIN RESULTS: One trial involving 33 couples was included. More infants in the treatment group were sleeping throughout the night by eight weeks of age than in the control group (odds ratio 0.04, 95% confidence interval 0.01 to 0.21). REVIEWER'S CONCLUSIONS: There is some evidence to show that first time parents using a structured sleeping programme can teach their babies to sleep through the night by eight weeks of age.

Breast Feeding↗
PubMed2000

Follow-up of steroid-resistant nephrotic syndrome: tubular proteinuria and enzymuria.

The aim of this study was to examine the compromise of proximal tubule cells in steroid-resistant nephrotic syndrome patients with a histologic diagnosis of focal segmental glomerulosclerosis (FSGS) through assessment of the urinary levels of beta 2-microglobulin (beta 2M) and N-acetyl-beta-D-glucosaminidase (NAG) during active disease and remission over a follow-up period of 3 years. We studied 34 children with nephrotic syndrome: 12 with steroid-resistant nephrotic syndrome (SRNS) and massive proteinuria, 7 with steroid-dependent nephrotic syndrome (SDNS) and 15 with steroid-sensitive nephrotic syndrome (SSNS). Of the SSNS patients, 8 children were in remission (RM) and 7 were in relapse (RL). Seven healthy children were included as controls. Urinary beta 2M, measured by enzyme-linked immunosorbent assay, was significantly increased in the SRNS group as compared to the SDNS group (P < 0.01), SSNS in remission (P < 0.01), and controls (P < 0.01). There were no differences between the SRNS group and SSNS in relapse. Analysis of urinary N-acetyl-beta-D-glucosaminidase (U-NAG) by colorimetric assay showed significantly higher values in the SRNS group of patients than in SDNS, SSNS, and control groups. A positive correlation between U-NAG and proteinuria was demonstrated (r = 0.73, P < 0.01). The SRNS group of patients (n = 12, 11 with a histologic diagnosis of FSGS and one with diffuse mesangial proliferation) was treated with the same protocol of i.v. methylprednisone and oral cyclophosphamide. Long-term follow-up showed a progressive decrease in U-beta 2M and U-NAG excretion to control values in the 3rd year, except in one patient who did not respond to the treatment. In the FSGS patients, evaluation of the contribution of structural interstitial histological abnormalities, including each of the histological parameters considered in interstitial scarring to the functional tubule abnormalities assessed by beta 2M and NAG excretion, was performed by multiple regression analysis. The r2 values for beta 2M and NAG were 53.99%, P = 0.19, and 57.90%, P = 0.14, respectively; neither was significant. We conclude that: (1) proximal tubule cell dysfunction, partially affected by massive albuminuria, may account for the higher values of beta 2M and NAG excretion in the SRNS patients and (2) urine beta 2M and NAG levels are not helpful in identifying histological evidence of structural tubulointerstitial damage in children with steroid-resistant nephrotic syndrome.

Acetylglucosaminidase↗
PubMed2000

A pilot survey of aberrant drug-taking attitudes and behaviors in samples of cancer and AIDS patients.

The clinical assessment of drug-taking behaviors in medically ill patients with pain is complex and may be hindered by the lack of empirically derived information about such behaviors in particularly medically ill populations. To investigate issues surrounding the assessment of these behaviors, we piloted a questionnaire based on the observations of specialists in pain management and substance abuse. This preliminary questionnaire evaluated medication use, present and past drug abuse, patients' beliefs about the risk of addiction in the context of pain treatment, and aberrant drug-taking attitudes and behaviors. This instrument was piloted in a mixed group of cancer patients (N = 52) and a group of women with HIV/AIDS (N = 111). Reports of past drug use and abuse were more frequent than present reports in both groups. Current aberrant drug-related behaviors were seldom reported, but attitude items revealed that patients would consider engaging in aberrant behaviors, or would possibly excuse them in others, if pain or symptom management were inadequate. Aberrant behaviors and attitudes were endorsed more frequently by the women with HIV/AIDS than by the cancer patients. Patients greatly overestimated the risk of addiction in pain treatment. We discuss the significance of these findings and the need for cautious interpretation given the limitations of the methodology. This early experience suggests that both cancer and HIV/AIDS patients appear to respond in a forthcoming fashion to drug-taking behavior questions and describe attitudes and behaviors that may be highly relevant to the diagnosis and understanding management of substance use among patients with medical illness.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Tollip, a new component of the IL-1RI pathway, links IRAK to the IL-1 receptor.

Interleukin-1 (IL-1) is a proinflammatory cytokine that elicits its pleiotropic effects through activation of the transcription factors NF-kappaB and AP-1. Binding of IL-1 to its receptor results in rapid assembly of a membrane-proximal signalling complex that consists of two different receptor chains (IL-1Rs), IL-1RI and IL-1RAcP, the adaptor protein MyD88, the serine/threonine kinase IRAK and a new protein, which we have named Tollip. Here we show that, before IL-1beta treatment, Tollip is present in a complex with IRAK, and that recruitment of Tollip-IRAK complexes to the activated receptor complex occurs through association of Tollip with IL-1RAcP. Co-recruited MyD88 then triggers IRAK autophosphorylation, which in turn leads to rapid dissociation of IRAK from Tollip (and IL-1Rs). As overexpression of Tollip results in impaired NF-kappaB activation, we conclude that Tollip is an important constituent of the IL-1R signalling pathway.

Adaptor Proteins, Signal Transducing↗