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Biomedical subjects

M Goldberg

Publications and source records attributed to M Goldberg.

At least 127 records · Page 7Linked to original sources
PubMed1999

Pleural incarceration of the gastric graft after trans-hiatal esophagectomy.

We report on a 73-year-old man who underwent a transhiatal esophagectomy for a T2N1M0 adenocarcinoma of the distal esophagus and developed an incarcerated herniation of the gastric graft through a defect in the right mediastinal pleura. The patient experienced delayed gastric emptying postoperatively, which was initially suggested by barium swallow. The gastric herniation was unidentified by early postoperative swallowing studies and endoscopies. After diagnosis by a later computed tomographic scan and barium study, the herniation was reduced by incising the mediastinal pleura from the diaphragm to the apex of the chest and by plication of the stomach longitudinally in order to reduce its intrathoracic diameter.

Adenocarcinoma↗
PubMed1999

Differences in the pattern of lanthanum diffusion into predentine and dentine in mouse incisors and molars.

Lanthanum nitrate was either perfused intravascularly or segments of mouse tooth were immersed in a fixative solution containing the tracer. The tracer deposits were examined in young (8-day-old) and older (8-week-old) mouse incisors and molars, demineralized or undemineralized. Lanthanum passed the distal junctional complex of odontoblasts and appeared in the predentine of incisors as large electron-dense stellate aggregates, 40-70 nm in diameter, and in molars as round, 20-40 nm dots. In dentine, tracer deposits were detected at three locations. Near the predentine dentine junction, the tracer densely stained a band 0.5-2.5 microm in width, also termed metadentine; in the inner circumpulpal dentine, the staining was weaker or lacking in an area extending 5-7 microm from the predentine-dentine junction; in outer circumpulpal dentine, lateral diffusion had occurred in porosities of intertubular dentine. Lanthanum impregnated the walls of dentine tubules and a peritubular-like dentine. In contrast, the mantle dentine was never stained. These differences in the pattern of diffusion prove that lanthanum staining is age-dependent and varies between mouse incisors and molars, independently of tissue processing. Architectural properties and driving flux are involved in the transport and localization of lanthanum in predentine and dentine.

Age Factors↗
PubMed1999

Feeding and respiratory gas exchange in the American dog tick, Dermacentor variabilis.

This study investigated the effect of blood feeding on respiratory gas exchange in the dog tick Dermacentor variabilis. Adult male and female ticks were fed on bovine hosts from 1 to 11days. Females fed slowly for the first 6days and then rapidly engorged on blood 2-3days prior to dropping from the host. Ticks were removed at daily intervals during feeding, weighed and CO(2) emission measured at 25 degrees C using flow-through respirometry. During feeding, females (N=39) showed a 100-fold gain in mass from 5.78+/-1.05mg to 541.15+/-18.60mg while standard metabolic rate (Vdot;co(2)) increased from 0.179+/-0.030&mgr;lh(-1) in unfed ticks to 87.32+/-5.72&mgr;lh(-1) in fully engorged ticks. CO(2) release prior to feeding was highly discontinuous with discrete spiracular bursts of CO(2) emission approximately every 30min. For CO(2) emission measured in detached partially or completely fed ticks, burst frequency became more and more rapid as feeding progressed and changed to continuous sustained CO(2) output during rapid engorgement. In contrast to females, male ticks (N=20) showed little change in mass and maintained discontinuous CO(2) throughout the 11day attachment period on the host. The switch from discontinuous to continuous CO(2) release and presumed increase in respiratory water loss in female ticks is correlated to an increase in metabolic expenditure associated with blood meal digestion rather than any factor relating directly to maintenance of water balance.

Journal Article↗
PubMed1999

Neurological complications of cardiac surgery: the need for new paradigms in prevention and treatment.

Neurological injury is a devastating complication of cardiac surgery that results in a longer duration of hospitalization, increased costs, and increased likelihood of death. Such injury can affect any level of the central nervous system, and its manifestations are broad, ranging from neurocognitive dysfunction to frank stroke. Many variables have been found to be indicative or risk for perioperative neurological injury, but the predictive models are more useful for stroke risk than for neurocognitive dysfunction. Strategies aimed at reducing neurological injury during cardiac surgery have focused, for the most part, on the technical aspects of cardiopulmonary bypass. The concomitant performance of carotid endarterectomy and cardiac surgery continues to be controversial, although the management of patients with symptomatic carotid stenosis is better defined. Cerebral embolism, including atheroembolism from the ascending aorta, has an important role in the pathogenesis of neurological injury of all types. Epiaortic ultrasound imaging of the aorta is a sensitive technique for the identification of atherosclerosis of the ascending aorta at the time of surgery, which can allow it to be avoided and therefore reduce the risk for atheroembolism. Results of laboratory investigations have provided insight into the mechanisms of ischemic neuronal injury and a basis for the development of neuroprotective drugs. Neuroprotection may best be accomplished during cardiac surgery because, in contrast to nonsurgical situations, potential agents can be administered before the neurological insult occurs. Reducing the incidence of perioperative stroke will require a multidisciplinary approach that includes novel diagnostic and therapeutic strategies.

Aortic Diseases↗
PubMed1999

Developmentally regulated changes in phospholipid composition in murine molar tooth.

In order to explore the possibility that phospholipids are differently expressed during the cascade of events leading to tooth formation, we decided to carry out simultaneous biochemical, histological and electron histochemical studies. High performance thin-layer chromatography and gas-liquid chromatography were used to compare the composition of embryonic mouse first molar tooth germs at day 18 of gestation (E18) and at birth (D1), erupting teeth at day 7 (D7) and erupted molars at day 21 (D21). For the latter, non-demineralized and EDTA-demineralized lipid extracts were analysed separately. Moreover, an ultrahistochemical study was carried out using the iodoplatinate reaction which retains and visualizes phospholipids. Developmentally regulated changes occurred and were closely correlated with an increase in cell membrane phospholipids. Gradual accumulation of phospholipids was identified in the extracellular matrix, at an early stage of tooth germ development within the basement membrane and later, as predentine/dentine and enamel components participating in mineralization processes. Matrix vesicles transiently present in dentine were partly responsible for the lipids that were detected. A first group of phospholipids including phosphatidylcholine as the major membrane-associated phospholipid and phosphatidylinositol as the intracellular second messenger increased by a factor of 2.3 between E18 and D21. This increase is probably associated with cell lengthening and was relatively modest compared with the higher increase detected for a second group of phospholipids, namely phosphatidylethanolamine (x4.8), phosphatidylserine (x 5.9) and sphingomyelin (x5.4). This second group of extracellular matrix-associated phospholipids constituted 68% of the demineralized lipid extract and, therefore, contributes to the mineralization of dental tissues.

Aging↗
PubMed1999

Stromelysin-1 (MMP-3) in forming enamel and predentine in rat incisor-coordinated distribution with proteoglycans suggests a functional role.

Stromelysin-1 (matrix metalloproteinase-3) or proteoglycanase was visualized by light and electron microscopy immunolabelling in the forming zone of rat incisors. In predentine, labelling was more dense at the transition zone between the inner proximal third and the two outer thirds. Odontoblast processes were also positively stained, mostly in predentine and to a lesser degree in dentine. The dentine-enamel junction was intensely labelled, whereas dentine and forming enamel were only faintly stained. Gold-antibodies complexes were seen inside secretory ameloblasts and odontoblasts in cytosolic locations. The distribution of stromelysin-1 was compared with the distribution of 2-B-6 epitope, an antibody recognizing chondroitin-4-sulphate/dermatan sulphate and which showed a decreasing gradient from the proximal zone to the distal part of predentine. In contrast, both 5-D-4, an anti-keratan sulphate antibody and an anti-lumican antibody displayed a reversed distribution, with an increase seen from the proximal and central thirds to the distal part of predentine. This coordinated distribution suggests that stromelysin-1 may have a functional role, being implicated in predentine in the degradation of chondroitin-4-sulphate/dermatan sulphate-containing proteoglycans, and consequently allowing keratan sulphate proteoglycan concentration to increase near the border where mineralization is initiated.

Ameloblasts↗
PubMed1999

Socioeconomic status, social mobility and cancer occurrence during working life: a case-control study among French electricity and gas workers.

OBJECTIVES: A case-control study within a cohort of the workers employed by Electricité de France and Gaz de France between 1988 and 1992 was carried out to investigate relationships between cancers and socioeconomic status, including the effects of social mobility, by studying three professional career points. METHODS: All the incident cases of breast cancer in women and all the incident cases of upper respiratory and digestive tract cancer (comprising cancers of the larynx, pharynx, buccal cavity and esophagus), lung cancer, hematopoietic system cancers and colon cancer in men were extracted from the Cancer Register of the Social Security Department. The controls were matched for age (men) and for age and length of employment in the company (women). Socioeconomic status was measured at three professional career points (beginning, midpoint (about 35), and time of diagnosis (about 48)) by two types of socio-professional variables: employee category (low, medium, high) and a variable based on the French socioeconomic status classification system. An estimation of social mobility was done between career beginning and midpoint. Cases and controls were compared for socioeconomic status at the three career points. They were also compared for social mobility. RESULTS: The differences between the social categories were larger at the start than later in the career for breast cancer in women. The category of operations staff was used as a reference, and this analysis shows a difference between the risks associated with supervisors (OR = 2.0) and managers and specialist professions (OR = 1.5). There were large differences according to the type of cancer in men. A socioeconomic gradient in the incidence of cancers of the upper respiratory and digestive tract was observed at every career stage. The gradient was largest at the moment of diagnosis. The odds ratio was 3.4 for supervisors, 7.8 for operations staff and 14.8 for production staff. There was a socioeconomic gradient in lung cancer at all points in the career and in the incidence of the hematopoietic system cancers at mid-career and at diagnosis. No association between socioeconomic status and colon cancer was found. Social mobility accentuated all these results. CONCLUSION: Socioeconomic status is involved in the development of cancers. Our study suggests that the transition from social to biological processes could act via specific lifestyle and/or work-related risk factors. When there is a social gradient in the incidence of a cancer, an individual's social change is at least as important as his/her original social status in the relationship between cancer and social class.

Adult↗
PubMed1999

Predictors of change in alcohol consumption among Frenchmen of the GAZEL study cohort.

AIMS: To identify the predictors of changes in alcohol intake among French men. DESIGN: Longitudinal study over a 2-year period. SETTING: The GAZEL volunteer cohort comprising workers employed by Electricité de France-Gaz de France. PARTICIPANTS: The study included 11,613 men aged 40-50 years who had answered a self-administered questionnaire in 1989 and 1991. MEASUREMENTS: Subjects were defined according to initial levels of alcohol intake and changes in that intake (cessation, decrease and increase) and compared with subjects with corresponding levels but unchanged intake by logistic regression. The effects of individual characteristics and of occupational and health conditions were investigated. FINDINGS: Different variables measured in 1989 were predictive of changes in alcohol consumption in 1991, depending on the change. Self-perception of bad health, consumption of sleeping pills and unmarried status were predictive of the cessation of alcohol consumption. Working under favourable conditions (with no specific occupational risks) and being a non-smoker tended to be associated with reduced consumption. Increased consumption was associated with the number of reported disease and the smoking status. Among abstainers or light daily drinkers, being exposed to more than one constraint enlarged the risk of increased consumption. For moderate drinkers, the risk of increased consumption was higher, irrespective of the number of physical constraints. CONCLUSIONS: These results highlight the fact that many inter-related factors help to determine changes in drinking habits.

Adult↗
PubMed1999

Comparative in-vitro activity of levofloxacin against isolates of bacteria from adult patients with community-acquired lower respiratory tract infections.

This study was conducted to evaluate the activity of levofloxacin in comparison with a range of antibacterial agents against recent isolates obtained consecutively from patients with community-acquired pneumonia (CAP) or acute exacerbation of chronic bronchitis (AECB) during the period 1995 to 1996. Susceptibility testing was carried out by either microdilution or the Etest, and interpreted according to NCCLS breakpoints. The activity of levofloxacin was compared with that of amoxycillin, amoxycillin-clavulanate, cefuroxime, cefixime, erythromycin, roxithromycin, clarithromycin, azithromycin, ofloxacin and ciprofloxacin. Clinically significant numbers of bacteria were recovered from 31 CAP and 94 AECB specimens. The predominant bacterial species in the CAP specimens were Streptococcus pneumoniae (21 isolates) and Haemophilus influenzae (four isolates). The AECB isolates mainly consisted of S. pneumoniae (38%), Moraxella catarrhalis (26%), H. influenzae (19%) and Pseudomonas aeruginosa (10%). The overall percentage susceptible of the isolates for each antibiotic was: amoxycillin, 64%; amoxycillin-clavulanate, 89%; cefuroxime, 87%; cefixime, 78%; erythromycin, 85%; roxithromycin, 87%; clarithromycin, 87%; azithromycin, 85%; ofloxacin, 95%; ciprofloxacin, 95%; and levofloxacin, 97%. The activities of levofloxacin and the other agents were also compared against 40 S. pneumoniae isolates, of which 20 were penicillin-non-susceptible, recovered from CAP and AECB specimens during the period 1994 to 1996. These strains were all susceptible to levofloxacin, but only 50% were susceptible to ciprofloxacin and 80% to ofloxacin. Twenty M. catarrhalis, 20 H. influenzae and 20 methicillin-susceptible S. aureus isolates were also all susceptible to levofloxacin. Furthermore, 20 community-acquired P. aeruginosa isolates showed similar percentage susceptible rates to levofloxacin and ciprofloxacin. These in-vitro results suggest that levofloxacin may be useful in the treatment of community-acquired lower respiratory tract infections.

Adult↗
PubMed1999

Completeness of and duration of time before treatment after screening women for Chlamydia trachomatis infections.

OBJECTIVE: To assess the proportion of women with verified treatment after positive screening tests for C. trachomatis infection and to evaluate the duration of time until treatment. DESIGN: Retrospective cohort analysis linking the date of a positive genital C. trachomatis test with the documented date of treatment. SETTING: Family planning, sexually transmitted disease, obstetrical/gynecologic, adolescent, and walk-in clinics in Philadelphia from March 1, 1994 through December 31, 1995. PARTICIPANTS: Included 4,158 women with screening tests positive for C. trachomatis. MAIN OUTCOME MEASURES: Documented treatment of chlamydia-infected women and duration of time between initial clinic visit and therapy. RESULTS: Over a 21-month period, 4,158 women had endocervical screening tests positive for C. trachomatis. Twenty-four percent of these women were treated presumptively (on the day of specimen collection), with sexually transmitted disease clinics yielding the highest percentage (70.9%) of presumptively treated patients. Of the 3,143 chlamydia-positive women not treated presumptively, treatment was subsequently verified in 96.2%. The median interval between screening and treatment was 21 days. Private adolescent clinics had the lowest median interval of 14 days between screening and treatment, whereas public family planning clinics showed the largest median screening to treatment interval of 26 days. CONCLUSIONS: Large-scale screening programs in public health settings can bring nearly all C. trachomatis-infected patients to treatment. However, new strategies are needed to shorten the duration of time before treatment of selected subsets of women who screen positive for C. trachomatis.

Adult↗
PubMed1999

Interleukin-12 as an adjuvant for an antischistosome vaccine consisting of adult worm antigens: protection of rats from cercarial challenge.

Our group previously demonstrated that a detergent extract (fraction S3) prepared from immature (4-week) Schistosoma mansoni parasites can induce partial, serum-transferable immunity to challenge infection in rats when administered as an alum precipitate. In the present study, we examined whether S3 prepared from adult (7-week) worms could similarly induce protection and whether immunity could be positively influenced by treatment with interleukin-12 (IL-12). IL-12 coadministered to Fischer rats and C57BL/6 mice at the time of S3 vaccination altered the prechallenge kinetics of S3-specific antibody titers in both species, ultimately leading to a stable enhancement of titers (relative to those in animals vaccinated without IL-12) in mice but not rats. Immunoblot analysis of prechallenge immune sera demonstrated that IL-12 treatment was associated with changes in the S3 antigen recognition profile in each species. Isotyping of specific antibodies in S3- plus IL-12-vaccinated mice prior to challenge infection revealed a moderate elevation in immunoglobulin G1 (IgG1) responses, strongly enhanced IgG2a and IgG2b responses, as well as diminished total serum IgE responses compared to those in mice given S3 only. In vaccinated rats, IL-12 profoundly suppressed specific IgG1 and enhanced IgG2b responses but did not affect IgG2a responses. S3- plus IL-12-vaccinated rats also produced less total IgE upon challenge infection. Enumeration of worm burdens revealed that vaccination with S3 plus IL-12 conferred 50% protection from cercarial challenge to rats, whereas rats given S3 only were not protected; mice were not protected by S3 vaccination regardless of IL-12 coadministration. The protection observed in S3- plus IL-12-vaccinated rats could not be transferred with serum, suggesting participation of an activated cellular component in the expression of immunity.

Adjuvants, Immunologic↗
PubMed1999

Sodium potassium adenosine triphosphatase activity in preterm and term infants and its possible role in sodium homeostasis during maturation.

AIM: To investigate sodium (NA(+)) potassium (K(+)) adenosine triphosphatase (ATPase) activity in newborn infants at different gestational ages, to elucidate the mechanism underlying poor renal sodium conservation in preterm infants. METHODS: Fifty three healthy newborn infants, gestational age 30-42 weeks, were studied. Umbilical cord red blood cell Na(+) K(+)ATPase activity, plasma renin activity, and plasma aldosterone activities were measured in all of them. Red blood cell Na(+) K(+)ATPase activity was re-examined in eight preterm infants, one and two weeks after birth. Total and ouabain sensitive ATPase activity was measured spectrophotometrically using a method that couples ATP hydrolysis with NADH oxidation. RESULTS: Red blood cell Na(+) K(+)ATPase activity was significantly lower (p<0.01) in preterm babies with a gestational age below 35 weeks, compared with those with aged 35 weeks and above: 2.3 (0.8) and 6.7 (1.3) nmol NADH/minute/mg protein, respectively. There was no correlation between gestational age, Na(+) K(+)ATPase, plasma renin activity and aldosterone values either in the preterm or term babies. Two weeks after birth, irrespective of gestational age, the enzyme activity of the preterm babies increased to values similar to those observed in the term neonates at birth. CONCLUSION: The differences in sodium homeostasis between term and preterm babies are modulated via changes in Na(+) K(+)ATPase activity.

Gestational Age↗
PubMed1999

The nuclear lamina: molecular organization and interaction with chromatin.

The nuclear lamina is located between the inner nuclear membrane and the peripheral chromatin. It is composed mainly of nuclear lamins and lamina-associated proteins. The nuclear lamina is involved in nuclear organization, cell cycle regulation, and differentiation. As such, impairment in its architecture and/or function leads to genetic diseases and apoptosis. This article describes the molecular organization of the nuclear lamins, their assembly into filaments, their distribution within the nucleus, and the complex network of interactions between them and other proteins of the inner nuclear membrane. Recent findings unraveled evidence for specific interactions between proteins of the nuclear lamina and the chromatin. These include interactions between nuclear lamins and core histones, Lamina Associated Polypeptide 2 (LAP2), and the Barrier to Autointegration Factor (BAF) and interactions between lamin B receptor (LBR) and the chromodomain protein HP1. Taken together, these studies attribute a role for both the nuclear lamins and the lamina-associated proteins, LAP2 and LBR, in nuclear organization and nuclear assembly.

Animals↗
PubMed1999

Surgical staging of lung cancer.

The staging of lung cancer defines the extent of disease. Accurate staging is important to define operability, select treatment regimens, and predict survival. Nonsurgical and surgical techniques are used to stage patients. The most important nonsurgical techniques used currently are the chest x-ray and computed tomographic (CT) scan of the chest and upper abdomen. In the future, positron emission tomography (PET) may become the single most important nonsurgical investigation. Surgical staging involves histologic assessment of the primary tumor and potential sites of metastases. At present, the standard for surgical staging is cervical mediastinotomy. Other minimally invasive surgical procedures used to stage patients with lung cancer are scalene lymph node biopsy, bronchoscopy with transbronchial biopsy, anterior mediastinoscopy, and video-assisted thoracoscopy. The different surgical staging options and their indications will be discussed in depth.

Biopsy↗
PubMed1999

[Regional differences in the compensation of pleural mesothelioma as occupational disease in France (1986-1993)].

BACKGROUND: Occupational exposure to asbestos is responsible for 80% at least of all mesothelioma in developed countries. In France there are important regional differences in the rate of mesothelioma compensated as occupational diseases, without knowing if these differences could be explained by a real difference of risk. The objective here is to quantify these regional differences in relation with the differences of level of risk. METHODS: The analysis compares, for each of the 16 regions of the national social security system, mortality for both genders and among men by pleural cancer (ICD 163) in the general population and mesothelioma compensated as occupational diseases during the 1986-1993 period. We computed for each region the number of expected compensated mesothelioma under the hypothesis where the regional distributions of compensated mesothelioma and mesothelioma deaths are the same; as well as the percentage of compensated mesothelioma compared to the deaths, and the variation from the national mean under two hypotheses, high and low; and the probability that a mesothelioma is compensated as an occupational disease taking as a reference the "best" region. RESULTS: The compensation rate differed significantly among regions (p < 0.05) and for men, the rate between observed and expected numbers of compensated mesothelioma varied from 0.15 (region of Montpellier) to 2.29 (region of Nantes), a ratio over 15. For all of France, the compensation rate was 25% under the best hypothesis. The region of Nantes compensated 61.5% of the male mesothelioma as occupational diseases, while the region of Montpellier and Clermont-Ferrand only around 5%. The probability for a mesothelioma to be compensated, compared to the region of Nantes, was 2.5 times less in national average, and about 10 times less in Montpellier and Clermont-Ferrand regions. CONCLUSION: In spite of limits linked to the imprecision of the available data, important regional differences in term of compensation of mesothelioma as occupational diseases clearly exist. Indications lead to think that their origin lies essentially in differences between physicians when considering the occupational etiology of mesothelioma, but differences within the system of compensation of occupational diseases can not be excluded. An improvement of the national statistical system concerning occupational diseases is highly recommendable.

Female↗