Localization of malachite green positive lipids in the matrix of bone nodule formed in vitro

An electron histochemical study was carried out on bone nodules formed in vitro in collagenase-released calvarial cells in order to visualize the lipid components of the extracellular matrix (EM). The malachite green aldehyde fixative technique, which allows both preservation and staining of some phospholipids of the extracellular matrix, was used. Controls were performed on sections demineralized, and then submitted to lipid extraction with a chloroformmethanol mixture (2/1 v/v) and to glycosaminoglycans digestion with 0.5% bovine testicular hyaluronidase to verify specificity for lipid staining. This allowed us to visualize the lipids (1) in the osteoid as granules associated to ribbon-like structures connected to the collagen fibers, (2) as electrondense deposits seen as dots on the outer surface membrane of the matrix vesicles, and (3) in the mineralized matrix as roundish patches formed of needle-shaped materials and at the mineralization front as individual ones. This study demonstrated that at the EM level, the lipids are present in the osteoid at locations very similar to what have been observed for the glycosaminoglycans, and in the mineralized matrix as components of the crystal ghosts.

Diverticuloplasty for severe mucosal injury after cricopharyngeal myotomy

Cricopharyngeal myotomy with either diverticulopexy or diverticulectomy is the recommended therapy for Zenker's diverticulum. Mucosal injury during myotomy is rare and usually can be managed by direct mucosal closure. A technique is described to repair a serious mucosal defect that may occur during cricopharyngeal myotomy.

Occupational risk factors for sinonasal cancer: a case-control study in France

A case-control study was conducted in France to examine occupational risk factors for sinonasal cancer; 207 cases and 409 controls were included in the study. Detailed information was collected on occupational history and other potential risk factors for nasal cancer. Results are presented for three histologic types: adenocarcinoma, squamous cell carcinoma, and others. Among males, the risk of adenocarcinoma was significantly elevated for cabinetmakers (odds-ratio = 35.4, 95% confidence interval = 18.1-69.3), carpenters and joiners (OR = 25.2, 95% CI = 14.6-43.6), and wood-working machine operators (OR = 7.4, 95% CI = 3.4-15.8), whereas the odds-ratios were less than 1 for loggers and wood preparation workers. Odds-ratios associated with cabinetmakers (OR = 11.2, 95% CI = 2.7-45.9)) and carpenters and joiners (OR = 5.8, 95% CI = 1.8-18.6) were also significantly elevated for the other-histologic-types category. Significant excesses in risk of squamous cell cancer were noted for "bakers, pastry cooks, grain millers" (OR = 3.9, 1.2-12.8), construction workers (OR = 3.7, 95% CI = 1.7-8.0), and carpenters and joiners having worked for at least 15 years in the wood manufacturing industry (OR = 8.1, 95% CI = 1.3-50.3). Among females, a significant increase in risk of squamous cell carcinoma (OR = 9.5, 95% CI = 1.7-54.1) and a moderate increase in risk of adenocarcinoma (OR = 4.0, 95% CI = 0.7-23.5) was observed for textile workers. Elevated risks of squamous cell cancer were noted for farm workers of both sexes (males: OR = 2.2, 95% CI = 1.1-4.4; females: OR = 4.9, 95% CI = 1.0-24.9).

Certified sick leave and work load. A case referent study among nurses

A case-referent study assessed the association of medically certified sick leave from work with some occupational characteristics: hospital, care unit, and two work-load indices (patients' average length-of-stay, and nurse-patient ratio). Study participants were nurses from seven general hospitals in Quebec City, who had been employed for at least 6 months at the time of study. Cases (n = 1165) experienced at least one episode of medically certified sick leave between January 1, 1984 and May 31, 1987. Referents (n = 1165) were chosen from subjects who had no such leave and were matched to cases on the basis of dates on which sick leave occurred. Occupational data were collected from employment records and administrative files. Analysis was conducted using multiple logistic regression. Statistically significant associations were found between sick leave and one hospital, two care units, and nurse-patient ratio among head nurses. These odds ratios were independent of length of service in the hospital or in the actual job assignment. The study supports the pertinence of using certified sick leave as a nonspecific indicator of health outcomes.

Onset of spontaneous labor and changes in E2 and progesterone levels--possible interrelation

Unlike the findings in animal studies, in which a decline in progesterone levels is clearly associated with the onset of labor, investigation of progesterone levels among human parturients has resulted in controversy. This study was designed to address the issue and evaluate labor-onset related changes of estradiol-progesterone (E2-P) concentration in fetal scalp serum, umbilical vein serum and in the peripheral maternal serum. Seven women in spontaneous labor, were compared to 7 women in whom labor was induced. Our results reveal a significant decrease in the maternal serum P concentration when spontaneous labor is taking place (120.6 +/- 24.5 mg/ml verus 177.3 +/- 61.4 mg/ml, p < 0.05). Significant change in the ratio of the fetal scalp to the maternal serum E2/P ratio in women at spontaneous labor versus induced labor is also shown. We could not demonstrate any changes in the E2 levels in relation to labor. We conclude that the onset of labor in human pregnancy is most probably preceded by local changes in the levels of P and ratio of P to E2. These changes may play an important regulatory role in onset of labor.

The effect of prenatal administration of dexamethasone and ritodrine on cord blood cortisol and glucose concentrations in premature infants with respiratory distress syndrome

The influence of maternal dexamethasone and ritodrine administration during pregnancy on cord blood cortisol and capillary serum glucose concentrations and on the incidence of respiratory distress syndrome (RDS) was studied in 30 premature infants (gestational age 27-36 weeks), and compared with a matched control group of 37 premature infants where no such medications were administered. RDS occurred less often in the treated group of infants (13.3%) than in the controls (35.1%, p < 0.01). The healthy treated infants had a significantly lower mean umbilical cord plasma cortisol concentration (5.5 +/- 1.8 ug/dl, mean +/- SD) than that observed in the controls (11.2 +/- 3.9 ug/dl, p < 0.01). Mean cord plasma cortisol concentrations increased with duration of pregnancy. No significant difference in the capillary serum glucose at 30 minutes post-delivery was found between the healthy, RDS, treated and non-treated infants. No adverse effects of steroid and ritodrine therapy were observed.

Monosymptomatic hypochondriacal psychosis: belief of contracting rabies

The authors describe a forty-one-year-old female with possible monosymptomatic hypochondriacal psychosis (MHP): a delusional belief that she had contracted rabies. This is the first report of this type of delusion in MHP. The patient failed to respond to multiple somatic therapies and finally made a serious suicide attempt. The authors discuss the reasons for the failed treatment and suggest a sequential protocol for treatment of MHP based on the current literature.

[Pteridine pattern in the urine of swine of different breeds and halothane genotypes in relation to nutrition and stress]

Urinary pteridine patterns and creatinine concentrations were determined in pigs of the breeds Piétrain, Deutsche Landrasse and their crossbreds. Also the influence of the halothane genotypes, of different feeding and of treadmill exercise was examined. We conclude that creatinine concentration in pig urine is not a reliable reference parameter for the pteridine excretion. Creatinine values were significantly influenced by breed and feeding. The pteridine pattern of pigs' urine depends on the breed and correlates with other metabolic parameters. Stress is reflected by altered pteridine concentrations.

Incidence of pleural mesothelioma in New Caledonia: a 10-year survey (1978-1987)

All cases of primary pleural cancers that were reported during a 10-y period (i.e., 1978-1987) in New Caledonia were recorded and compared with five cancer registers. There was an excess of primary pleural cancers in the area of New Caledonia, and it was particularly evident among the Melanesian ethnic group. Neither geographical nor occupational factors accounted for these results, but an environmental factor could not be excluded.

More Munchausen with chronic pain

Munchausen's syndrome is a popular name for a factitious disorder with physical symptoms. We have identified four Munchausen patients within a sample of 2,860 chronic pain patients for a frequency of 0.14%. These patients are described and an attempt is made to develop a profile of the Munchausen patient presenting with chronic pain.

Chronic pain patients and the nonorganic physical sign of nondermatomal sensory abnormalities (NDSA)

The nonorganic physical sign of nondermatomal sensory abnormalities (NDSA) is frequently found in chronic pain patients. The presence of NDSA qualifies the patient for a potential DSM-III diagnosis of conversion disorder. DSM-III (Axis I and II) diagnoses and personality styles were assigned to 283 mixed chronic pain patients. Discriminant analysis was used to identify diagnoses and personality styles significantly related to NDSA. The demographic variables of workers' compensation (WC) status, age, sex, and race were used as control variables. The discriminant function comprised all control variable, and psychiatric diagnoses accounted for only 22.1% of the variance. Age and WC status, i.e., the demographic variables, explained most of the variance (16.8%), with psychiatric diagnoses adding little (5.3%). The vast majority of the variance is unexplained, indicating the presence of "unexplained" factors for the presence of NDSA in chronic pain patients.

Specific interchain cross-linking of antibodies using bismaleimides. Repression of ligand leakage in immunoaffinity chromatography

The extensive use of antibody-containing affinity columns in the purification of biologically active compounds (e.g., genetically engineered proteins) is severely hampered by the leaching of antibody (or portions thereof) from the immunoaffinity resin during elution of the target antigen. One of the major problems in this context is the combined use of reducing (i.e., thiols) and chaotropic (e.g., detergents and denaturants) agents in the elution step, which causes the disassociation of heavy and/or light chains from the immobilized antibody, thereby contaminating the resultant product. In order to overcome this problem, we have cross-linked the four antibody chains at their sites of disulfide interlinkage, thus producing a single antibody chain. To accomplish this, interchain disulfide bonds were reduced, and the resultant thiol groups were cross-linked by using bifunctional SH-specific reagents (particularly bismaleimides). Cross-linking of up to 95% of the available SH groups produced was achieved with concomitant retention of antigen-binding activity. The cross-linked antibody was immobilized onto CNBr-activated Sepharose, and the resultant column was found to be substantially more stable to harsh elution conditions than similar columns which contain the un-cross-linked antibody.

[Pilot study of the relationship of free amino acids in serum and in the cerebrospinal fluid of horses]

In a blind study serum and cerebrospinal fluid (CSF) of control horses and of horses in hepatic coma after chronic food intoxication with Senecio alpinus were collected simultaneously and the composition of free amino acids was determined. The hepatic encephalopathy index in serum (less than 1.65) and in CSF (less than 1.11) of liver patients was distinctly less than to the control values in serum (greater than 2.42) and in CSF (greater than 1.49). The serum concentrations of glutamic acid in hepatic coma were elevated five-fold in comparison to the controls. An indication of ammonia decontamination was that nearly ten-fold higher values of glutamine were found in the cerebrospinal fluids of patients than in serum. In comparison to controls the serum levels of glutamine in horses with hepatic encephalopathy were decreased by the factor 0.7.

[Effect of rotary instruments on composites for coronal restoration. A proposed evaluation protocol for the effect of rotary instruments and surface conditions]

Numerous core composites are used to reconstruct abutments for fixed partial dentures. The preparation is carried out with various type of burs. The purpose of this study is to facilitate the choice among them. Six chemical composites, one glass ionomer cement and two light cured composites have been selected. Calibrated samples have been made, divided into four series and prepared with six different burs used for fixed partial dentures, three of them as finishing burs. In the first part of the investigation, the samples were examined with a S.E.M., in order to visualize the surface texture. According to the materials used, variations may exist. In the second part of the investigation, a tridimensional study was performed using a mechanical scanner microscope which permitted the quantification of some roughness characteristics, thus, an objective comparison of the surfaces became possible. Due to the complementary nature of the two investigation techniques, a protocol is presented for the study of burs instrumentation and prepared tooth surface.

Scanning electron microscopy of the forming enamel of rat incisor: influence of fixative and treatments interacting with the organic matrix

The forming enamel of rat incisor was either treated before fixation with one of these five treatments: ultrasonication, NaOCl, chloroform/methanol, NaOH or tween 20; or the incisors were first fixed and then submitted to one of these treatments. The structure of the forming enamel, compared with sections fixed with aldehyde and submitted to osmic maceration, depends on the way the samples were treated and on the fixative used. An amorphous material, removed by osmium tetroxide but not by aldehyde solution was seen to be located between fiber-like structures. In the region of inner enamel secretion the thickness of interrod septa was fairly constant, whereas in the region of outer enamel secretion, transverse septa of interrod enamel gradually became thinner and finally disappeared. The longitudinal septa did not display such changes. Longitudinal grooves and ridges were seen at the end of enamel completion. These longitudinal septa finally merged and formed a flat surface.