Allergenic structures in cockroach hypersensitivity

The tissues from which cockroach allergens were derived were identified by use of serum IgE of five patients with allergic rhinitis and bronchial asthma as a result of hypersensitivity to German cockroach. RAST and skin test results demonstrated four of five patients to be positive to cockroach only, and one patient was tested positive to house dust mite as well. Allergen-specific IgE binding to German cockroach was investigated by cryostat sections by means of immunofluorescent test. In all patients with cockroach hypersensitivity, we found IgE bound to the gastrointestinal epithelium and contents of the intestinal tract. In four cases, IgE was also bound to the Malpighian vessels (equivalent in function to kidneys). In three cases, IgE was also bound to the ovarian cells. All cases revealed cytoplasmic staining.     

Regulated recruitment of HP1 to a euchromatic gene induces mitotically heritable,epigenetic gene silencing: a mammalian cell culture model of gene variegation

Heterochromatin protein 1 (HP1) is a key component of constitutive heterochromatin in Drosophila and is required for stable epigenetic gene silencing classically observed as position effect variegation. Less is known of the family of mammalian HP1 proteins, which may be euchromatic, targeted to expressed loci by repressor-corepressor complexes, and retained there by Lys 9-methylated histone H3 (H3-MeK9). To characterize the physical properties of euchromatic loci bound by HP1, we developed a strategy for regulated recruitment of HP1 to an expressed transgene in mammalian cells by using a synthetic, hormone-regulated KRAB repression domain. We show that its obligate corepressor, KAP1, can coordinate all the machinery required for stable gene silencing. In the presence of hormone, the transgene is rapidly silenced, spatially recruited to HP1-rich nuclear regions, assumes a compact chromatin structure, and is physically associated with KAP1, HP1, and the H3 Lys 9-specific methyltransferase, SETDB1, over a highly localized region centered around the promoter. Remarkably, silencing established by a short pulse of hormone is stably maintained for >50 population doublings in the absence of hormone in clonal-cell populations, and the silent transgenes in these clones show promoter hypermethylation. Thus, like variegation in Drosophila, recruitment of mammalian HP1 to a euchromatic promoter can establish a silenced state that is epigenetically heritable.     

Characterization of auromomycin-resistant hamster cell mutants that display a multidrug resistance phenotype

We have selected and characterized Chinese hamster ovary (CHO) cells resistant to auromomycin (AUR), an antitumor antibiotic composed of a protein moiety and a nonpeptide chromophore. AUR is cytotoxic as a consequence of DNA strand-scission activity associated with the chromophore. Initial single-step selections for clones resistant to AUR detected a subpopulation of phenotypically resistant colonies, but nearly all such clones failed to display heritable resistance. One isolate that did show somewhat increased resistance was selected further and yielded a clone designated AURR-R1 that exhibits stable 10-fold increased resistance to AUR. The R1 line is also resistant to the AUR chromophore and cross-resistant to the closely related agent neocarzinostatin (NCS) and to the NCS chromophore. For AUR-treated whole cells, resistance to AUR cytotoxicity was inversely correlated with DNA damage as measured by filter elution; by contrast, isolated nuclei from sensitive and resistant cells displayed similar levels of AUR-induced DNA damage. The R1 cell line was found to be cross-resistant to colchicine, Adriamycin, Daunomycin, and vinblastine. The resistance phenotype is expressed with incomplete dominance in cell hybrids and appears similar to the "classic" multidrug resistance of CHO cells selected with other agents. Indeed, we found the multidrug-resistant CHO line CCHR-C5 to be about 5-fold cross-resistant to AUR and to NCS. We ascertained that AUR-resistant (AURR) isolates express elevated levels of the molecular weight 170,000 P-glycoprotein often associated with multidrug resistance and also contain amplified DNA sequences that contain the gene for P-glycoprotein. When multiple-step enrichment selections were carried out as an alternative approach for isolating AURR mutants, each of nine clonal isolates showed phenotypes resembling the AURR-R1 line. Thus, our findings imply that increased cellular resistance to AUR may frequently be associated with P-glycoprotein-mediated multidrug resistance.     

Bernard J. Reilly,M.A., M.B., Ch.B., FRCPC Gold Medalist the Society for Pediatric Radiology 1991

Gold Medalists of the Society for Pediatric Radiology 1991

Bernard J. Reilly, M.A., M.B., Ch.B., FRCPC Gold Medalist the Society for Pediatric Radiology 1991     

Relation between body mass index and lung cancer risk in men and women never and former smokers

The authors assessed body mass index (BMI), measured as Quetelet's index (weight in kilograms divided by the square of height in meters), in relation to lung cancer risk in never and former smokers by using data from a population-based, individually matched, case-control study conducted in New York State from 1982 to 1985. To be included in the study, subjects must never have smoked more than 100 cigarettes in their lifetime (never smokers) or not have smoked more than 100 cigarettes during the last 10 years (former smokers). Data on height and weight were complete for 412 of 439 case-control pairs. A positive relation was found between BMI and lung cancer risk for both never smokers (188 case-control pairs) and former smokers (224 pairs). When subjects were combined, those in the eighth (highest) octile (BMI > 30.84) had more than twice the odds of being cases compared with those in the lowest octile (BMI < or =21.26, 95 percent confidence interval: 1.2, 4.4). These study results are consistent with those from studies of BMI and other cancer sites but differ from lung cancer results usually found in predominantly smoking populations.     

“I’d Know That My Child Was Out There”: Egg Donation,the Institutionalized “Ideal” Family,and Health Care Decision Making

This study investigates how young women of egg-donating age perceive egg donation. Using institutional theory, this study demonstrates how participants frame a health care decision, such as egg donation, utilizing familial ideals. Results revealed that women expressed the importance of ownership over their genetic material and that familial ideals encourage an ideal way to create a family, which egg donation only fits as a last resort. Results show that familial ideals reach past the institution of family into broader decision making, such as that of health care. Further, results show that as more families are constructed through assisted reproductive technologies, attempts should be made to gradually alter the familial ideal to encompass novel medical technologies such as egg donation.     

Conversion of oral alfacalcidol to oral calcitriol in the treatment of secondary hyperparathyroidism in chronic hemodialysis patients

International Urology and Nephrology - The optimal vitamin D3 therapy for the treatment of secondary hyperparathyroidism (SHPT) in chronic hemodialysis patients is still controversial. Recent...     

Systemic hypertension in snorers with and without sleep apnea.

To investigate the impact of sleep-disordered breathing events on daytime hypertension (HT) in patients with increased upper airway resistance during sleep, we studied 191 male snorers aged 49.9 +/- 0.8 years. In 116 of them, an apnea-hypopnea index (AHI) above 10--defined as the presence of obstructive sleep apnea (OSA)--was found; the other 75 subjects had an AHI lower than 10 and were classified as habitual snorers (HSN). Prevalence of HT was not different between OSA (56 of 116 = 48 percent) and HSN (33 of 75 = 44 percent) and there was also no difference in systolic, diastolic, and mean blood pressures between the two groups. Hypertensive OSA patients had higher body mass index (BMI) than normotensive OSA subjects (31.4 +/- 0.7 vs 29.4 +/- 0.6; p less than 0.05), but there was no difference in age, AHI, and nocturnal oxygenation parameters. The same was true for the HSN group, with hypertensive subjects being more obese than normotensive subjects (BMI: 30 +/- 0.8 vs 27.3 +/- 0.8; p less than 0.05), but no difference in age and polysomnographic features. Discriminant analysis with HT as the classification variable and age, BMI, AHI, mean, and lowest nocturnal oxyhemoglobin saturation as independent variables, revealed an independent influence on HT only for BMI (F-prob = 0.001). Thus, our results stand against the hypothesis of a causal relationship between sleep-disordered breathing events and daytime hypertension. We conclude that the high prevalence of HT in male snorers is more directly linked to obesity than to sleep apnea, but an independent effect of snoring per se cannot be excluded.     

The role of head and neck cancer advocacy organizations during the COVID‐19 pandemic

The COVID‐19 pandemic has had a significant impact on many aspects of head and neck cancer (HNC) care. The uncertainty and stress resulting from these changes has led many patients and caregivers to turn to HNC advocacy groups for guidance and support. Here we outline some of the issues being faced by patients with HNC during the current crisis and provide examples of programs being developed by advocacy groups to address them. We also highlight the increased utilization of these organizations that has been observed as well as some of the challenges being faced by these not‐for‐profit groups as they work to serve the head and neck community.