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Biomedical subjects

M A Kane

Publications and source records attributed to M A Kane.

At least 19 recordsLinked to original sources
PubMed2001

Effects of fluorescent probe structure on the dynamics at cysteine-34 within bovine serum albumin: evidence for probe-dependent modulation of the cybotactic region.

We have prepared a series of bovine serum albumins (BSA) that have been site-selectively labeled at cysteine-34 with one of four different sulfhydryl-selective boron dipyrromethene difluoride (BODIPY) fluorescent probes (BODIPY FL IA, BODIPY FL C(1) IA, BODIPY 530/550 IA, and BODIPY 493/503 MB). We determine how the choice of extrinsic probe structure dictates the recovered BSA-BODIPY dynamics under thermal (10-80 degrees C) and chemical (0-5M guanidine hydrochloride) denaturation conditions. The results of these experiments show that the global protein dynamics are sensed equally by each fluorescent probe; however, the probe itself influences the local probe dynamics within the cybotactic region that surrounds cysteine-34. Thus, it seems inappropriate to think of these extrinsic fluorescent probes as passive, nonparticipatory viewers of local protein dynamics.

Animals↗
PubMed2000

Infant and adolescent hepatitis B immunization up to 1999: a global overview.

This article presents a global overview of hepatitis B infant and adolescent immunization programmes. The 108 reported universal infant or adolescent immunization programmes and 87 reported national infant coverage rates fit a pattern, explained by hepatitis B endemicity, prosperity, policy emphasis, and immunization programme strength. Most East and Southeast Asian, Pacific, and Middle Eastern countries have intermediate to highly endemic hepatitis B. Most have achieved 65-100% coverage. South and Central Asia and sub-Saharan Africa have intermediate to high endemicity, with some countries having hepatitis B immunization programmes. Some Southern and Eastern European countries, with intermediate endemicity, have high coverage. Low endemic Northern European countries vaccinate higher risk groups; some have universal infant or adolescent programmes. Caribbean and Latin American countries have varying endemicity, and most started programmes. Low endemic North American countries have universal vaccination programmes. Universal immunization strategies have greatly reduced incidence and prevalence, and are cost-effective for many countries, but many have difficulties affording this vaccine. Globally, most infants are not being immunized against hepatitis B virus infection. Increasing coverage, and decreasing the numbers of people diseased and dying from this virus, may require delivering heat-stable vaccine beyond cold chains, creative financing to reduce prices, and multivalent vaccines.

Adolescent↗
PubMed2000

Nicotine effects on proliferation and the bombesin-like peptide autocrine system in human small cell lung carcinoma SHP77 cells in culture.

OBJECTIVES: To determine whether nicotine affects the proliferation and expression of the bombesin-like peptide autocrine system in human small cell lung carcinoma (SCLC) SHP77 cells compared with nonmalignant human bronchial epithelial BEAS 2B cells as non-neuroendocrine controls. METHODS: Human lung cells were cultured in defined serum-free medium with various concentrations of nicotine added for various times. Proliferation was measured by cell counts and colorimetric assay, bombesin-like peptide receptor expression was assayed by specific binding assays and quantitative competitive PCR, and bombesin-like peptides determined by ELISA. RESULTS: Nicotine significantly stimulated the growth of human SCLC SHP77 and NCI-H865 cells, but not BEAS 2B cells. Bombesin-like peptide receptor specific binding and mRNA expression were not affected by nicotine exposure in SHP77 cells or BEAS 2B cells. An increase in SHP77 cellular bombesin-like peptide content was observed. CONCLUSIONS: Human SCLC SHP77 cells express the components of the bombesin-like peptide autocrine system. Increased proliferation in the presence of nicotine may be due in part to increased levels of bombesin-like peptides in SHP77 cultured in nicotine. Nicotine effects on nonmalignant pulmonary neuroendocrine cells may provide additional insight into how nicotine itself may promote lung carcinogenesis.

Binding, Competitive↗
PubMed1999

Nonsurgical treatment of platysmal bands with injection of botulinum toxin A.

Botulinum toxin A has been used therapeutically in humans for over 20 years for a variety of medical indications. For the past 7 years, the author has injected it for cosmetic purposes in a variety of muscles of the head and neck. Fifty patient-injections of the platysma muscle were performed in an attempt to correct platysmal banding. An improvement was seen in all patients who presented to the office for follow-up in a timely manner (44 injections). Results were limited by redundant skin. No incidence of dysphagia or airway obstruction was encountered. The only complication noted was bruising. Although at least a small improvement in platysmal banding was seen in all patients, in no patient was there evidence of lifting of the lower face. All results were temporary.

Botulinum Toxins, Type A↗
PubMed1998

[World-wide epidemiology of hepatitis B].

Hepatitis B is one of the major infectious diseases of mankind with 350,000,000 chronic carriers at high risk of death from cirrhosis and primary liver cancer. The probability of becoming a chronic HBV carrier following infection depends primarily on age, and ranges from 70% following mother to child transmission to less than 10% following adult infection. The world is conceptually divided into regions of high, intermediate, and low endemicity, with predominant modes of transmission differing by region. In Asia and Africa, most transmission occurs among children, whereas in Western Europe and North America most transmission occurs during early adult life due to lifestyle, occupational exposures, or exposures within ethnic groups where the virus is endemic.

Adult↗
PubMed1998

[World-wide status of hepatitis B vaccination 1998].

In 1991 WHO recommended that all countries include HB vaccine into their routine childhood immunization programmes. By 1998, more than 90 countries have included HB vaccine as routine antigen in their national programmes. These countries include about half of the world's children and about 70% of the world's carriers. The WHO target is to prevent 80% of new HBV carriers in children by the year 2001 by adding the vaccine into routine immunization. The vaccine has proven to be 85% to 95% effective in preventing the chronic carrier state in population based studies from many countries. Studies in Taiwan have already shown a direct reduction of liver cancer in immunized children. The major remaining problem is to develop financial mechanisms to allow the children in the poorest countries to benefit from this important vaccine.

Child↗
PubMed1998

Status of hepatitis B immunization programmes in 1998.

More than 90 countries have now included hepatitis B (HB) immunization into their National Immunization Programmes as a routine vaccine given to all infants and/or adolescents and many additional countries are planning for the introduction in the next two years. These countries include all industrial countries except the United Kingdom, Ireland, The Netherlands, the Scandinavian countries and Japan. Countries with routine HB immunization include about 45% of surviving new-borns, but almost 70% of hepatitis B virus carriers live in countries with routine HB programmes. Population based studies of HB immunization from around the world are now being reported with as long as 10 to 15 years of follow-up, showing a reduction of the chronic HB carrier prevalence from high (8% or greater) to low (less than 2%) endemicity in immunized cohorts of infants. Reductions in the price of HB vaccines, a significant increase in the number of producers and the advent of combination vaccines including an HB component will make the vaccine available to more children world wide, but economic constraints continue to hamper introduction of this vaccine to the children in the poorest countries.

Hepatitis B↗
PubMed1998

Diplopia following transconjunctival blepharoplasty.

The resurgence of popularity of the transconjunctival approach to lower eyelid fat removal as a component of cosmetic blepharoplasty has been highlighted by a number of publications in recent years. There has been, however, minimal discussion in the literature of the complications of this procedure. Although the mechanism of muscle injury is similar in transcutaneous and transconjunctival surgery, there is a much more direct route to the inferior extraocular musculature via the latter approach. Herein, we present a series of six patients with diplopia status post-transconjunctival lower eyelid blepharoplasty referred to the Manhattan Eye, Ear, and Throat Hospital for evaluation. Transconjunctival lower lid blepharoplasty was performed as a primary procedure in four patients and as a secondary procedure following transcutaneous blepharoplasty in two patients. Patients were evaluated with ocular examination and orthoptic measurements. Magnetic resonance imaging was obtained in two cases. The inferior rectus and inferior oblique muscles were found to be equally injured in these cases (4 of 6), and the lateral rectus was encountered in one case. Two patients required strabismus surgery to correct their diplopia, whereas four patients improved with observation alone. The possible etiologies of postoperative diplopia following transconjunctival lower lid blepharoplasty are manifold. Mechanisms of extraocular muscle injury may include intramuscular hemorrhage and edema, cicatricial changes within the muscle, and accidental incorporation of extraocular muscle in closure of orbital septum. Avoidance of these complications is probably best achieved through intimate understanding on the part of the surgeon of eyelid anatomy from the transconjunctival perspective.

Adult↗
PubMed1997

Hepatitis viruses and the neonate.

Great progress has been made in the last 10 years in the understanding of the various types of viral hepatitis, and new viruses, concepts, therapies, preventive measures, and control strategies have been recognized. Even more agents, vaccines, and drugs will be discovered or developed in the future, and pediatricians increasingly will be expected to provide guidance to patients and to the community on the importance and use of these new tools.

Carrier State↗
PubMed1996

Clinical correlates of bombesin-like peptide receptor subtype expression in human lung cancer cells.

The importance of the expression of the autocrine growth system for bombesin-like peptides (BLPS) to the biological behavior of human lung cancer has not been determined. Three BLP receptor subtypes have been identified in human lung and lung cancer cells: gastrin-releasing peptide (GRP) receptor, neuromedin B (NMB) receptor, and bombesin receptor subtype 3 (BRS-3). The goals of this study were: (1) to determine BLP receptor subtype expression by human lung cancer cell lines by RT/PCR; (2) to evaluate possible clinical correlates of characteristics of the patients from whom the cell lines were derived with patterns of BLP receptor expression. Degenerate PCR primers were designed to amplify all known BLP receptors and yielded products from 19/20 small cell lung carcinoma (SCLC) and 12/13 non-small cell lung carcinoma (NSCLC) cell lines. GRP receptor was the most commonly expressed BLP receptor subtype, being detected in 17/20 SCLC and 11/13 NSCLC. Eleven of 20 SCLC expressed NMB receptors, and 5/20 expressed BRS-3, compared with 4/13 and 1/13, respectively, in NSCLC cell lines. Evaluation of the clinical data of the patients from whom the cell lines were derived revealed expected age, sex, smoking history and survival based on histology and stage. Patients from whom cell lines expressed GRP receptor experienced a better survival than those whose cell lines did not (367 +/- 274 days vs. 211 +/- 114 days), but the results were not statistically significant. RT/PCR analysis is a feasible, sensitive and specific means of determining BLP receptor expression in lung cancer cells and may yield prognostic information in patient tissue.

Biomarkers, Tumor↗
PubMed1996

Bombesin-like peptide receptors in human bronchial epithelial cells.

Northern blot and RNAse protection assays previously failed to detect bombesin-like peptide (BLP) receptors in normal human lung tissue, but by RT/PCR cultured human bronchial epithelial (HBE) cells expressed all three BLP receptor subtypes, predominantly neuromedin B (NMB) receptor. By RT/PCR, we found expression of all three BLP receptor subtypes by human lung tissue and confirmed NMB receptor expression in six out of six HBE samples. However, transformed HBE BEAS B2B cells expressed only gastrin-releasing peptide (GRP) receptors; saturable, high-affinity (Kd = 3.5 nM) specific [125I]GRP binding confirmed functional GRP receptor, with M(r) = 75 kDa and immunologic cross-reactivity with GRP receptor from human small-cell lung carcinoma (SCLC) NCI-H345 cells. Altered regulation of BLP receptors may accompany transformation of normal lung cells to cancer.

3T3 Cells↗
PubMed1996

Oncogenic signaling.

Cancer develops when one or more cells begin to grow uncontrollably, presumably as a result of alterations in the highly regulated processes of normal cell division. These changes may result from germline or somatic mutations in genes that control normal cell proliferation, resulting in oncogenes. Oncogenes--originally defined as viral genes that transformed mammalian host cells--code for proteins with diverse functions. Antioncogenes, or tumor-suppressor genes, code for proteins acting as brakes in the cell cycle. Mutations in or deletions of these genes release the brakes. An overview of cellular signaling pathways, how they may be altered in cancers, and recently reported clinical implications of abnormal expression of some oncogenes and tumor-suppressor genes will be presented here.

Genes, Tumor Suppressor↗
PubMed1996

Nonconstitutive expression of the gastrin-releasing peptide autocrine growth system in human small cell lung carcinoma NCI-H345 cells.

Constitutive, unregulated autocrine growth is thought to be an important mechanism whereby cancer cells gain a proliferative advantage over nonmalignant cells. The question addressed here was whether the autocrine growth system for gastrin-releasing peptide (GRP) in human small cell lung carcinoma cells is, in fact, always expressed in a constitutive, unregulated fashion. Lag, rapid, and plateau growth states were defined for small cell lung carcinoma NCI-H345 cells based on periods during which they expressed different growth rates after plating as single cell suspensions. Immunoreactive GRP in the conditioned medium and in NCI-H345 cells harvested during each of these growth states, as well as cell DNA content, GRP mRNA expression, specific 125I-GRP uptake, specific 125I-GRP binding to solubilized membranes, and GRP and neuromedin B receptor mRNA expression by reverse transcription-PCR were analyzed. Maximal levels of GRP expression were observed during the lag growth state, with the highest concentration of immunoreactive GRP in the conditioned medium during the rapid growth state. Specific 125I-GRP uptake and binding were also highest during the lag growth state; however, GRP receptor mRNA did not significantly change. In contrast to prevailing concepts, these studies support the conclusion that the expression of the GRP autocrine growth system in NCI-H345 cells is indeed regulated. Furthermore, the components are maximally expressed before rapid growth begins, suggesting that other mechanisms are activated to support the actual proliferation.

Antibody Specificity↗
PubMed1995

Properties of classic protein kinase C in human small cell lung carcinoma NCI-H345 cells.

Bombesin-like peptides (BLPs) activate protein kinase C (PKC), which leads to proliferation in nonmalignant Swiss 3T3 cells. The purpose of this study was to determine if PKC expression in the classic human small cell lung carcinoma NCI-H345 cell line, which has an autocrine growth loop involving BLPs, exhibited unique properties that could result in malignant behavior. PKC activity and phorbol dibutyrate binding in NCI-H345 cells had properties similar to other reports. PKC activity in the cytosolic fraction increased to 100% as cells proliferated through lag, log, and plateau growth states. However, during the first 3 days after plating (lag growth state), 40-50% of the PKC activity was membrane associated, indicating a substantial portion in an activated form, possibly a result of BLP autocrine stimulation. NCI-H345 cells expressed the PKC isoenzymes alpha, beta, delta, sigma, and eta, but not gamma or epsilon, a pattern different from Swiss 3T3 cells or normal brain. further characterization of the Ca2+/phospholipid-dependent (classic) PKC isoenzymes, alpha and beta, showed that PKC beta was predominantly cytosolic (80%) as expected, but PKC alpha was primarily membrane associated (80-90%). Exposure of NCI-H345 cells to 200 nm phorbol 12-myristyl 13-acetate rapidly (within 2 min) decreased cytosolic PKC activity, with no change in the particulate activity, but did not alter [3H]-thymidine incorporation or subcellular distribution of PKC alpha or beta by Western blot. These results suggest altered PKC regulation in human small cell lung carcinoma NCI-H345 cells, which could contribute to their malignant behavior.

3T3 Cells↗
PubMed1994

Epidemiology and prevention of hepatitis A in travelers.

OBJECTIVE: To assess the risk of hepatitis A in international travelers and to recommend preventive measures. DATA SOURCES: Index Medicus, 1974 through 1983; MEDLINE, 1984 through 1993; and unpublished data of the Centers for Disease Control and Prevention. STUDY SELECTION: Review of all retrospective and cohort studies on hepatitis A and other vaccine-preventable diseases in travelers, of seroepidemiologic surveys of hepatitis A virus (HAV) antibodies in travelers, of data on the various hepatitis A vaccines, of economic analyses, and of recommendations of recognized organizations. DATA EXTRACTION: Independent analysis by multiple observers. DATA SYNTHESIS: The incidence rate for unprotected travelers, including those staying in luxury hotels, is estimated to be three per 1000 travelers per month of stay in a developing country. Persons eating and drinking under poor hygienic conditions have a rate of 20/1000 per month. This makes hepatitis A the most frequent infection in travelers that may be prevented by immunization. In many industrialized countries persons born after 1945 have an HAV antibody seroprevalence (immunity) of less than 20%. New inactivated HAV vaccines induce protective antibodies in more than 95% of recipients and offer protection estimated to last for 10 years or more, whereas protection by immune globulin lasts only 3 to 5 months. CONCLUSIONS: Hepatitis A vaccine, or immune globulin where HAV vaccine is not available, is recommended for all nonimmune travelers visiting developing countries. Prescreening for antibodies to HAV in travelers living in countries with low prevalence is usually not necessary in persons born after 1945.

Cost-Benefit Analysis↗
PubMed1994

Human melanoma cells express functional endothelin-1 receptors.

Current evidence suggests that endothelium-derived factors enhance human melanoma vascular invasion. Therefore, we studied human melanoma cell expression of receptors to the endothelium-derived peptide, endothelin-1 (ET-1), and determined if they respond to ET-1 with proliferation and chemokinesis. Human metastatic melanoma cell lines were found to have specific, saturable, high affinity ET-1 binding. Northern analysis and competitive inhibition studies confirmed that melanoma cells express the ETB receptor isoform. Ten nanomolar ET-1 caused an 8.2 to 25.5-fold increase in intracellular free calcium. ET-1 was found to be a weak mitogen for melanoma cells, however, melanoma cell chemokinesis was significantly increased by ET-1. These data suggest that ET-1 may be involved in providing a chemokinetic and growth factor environment that enhances perivascular proliferation and invasiveness of melanoma cells.

Calcium↗