RESUMEN

Deficiency of any component of the ER-resident collagen prolyl 3-hydroxylation complex causes recessive osteogenesis imperfecta (OI). The complex modifies the α1(I)Pro986 residue and contains cartilage-associated protein (CRTAP), prolyl 3-hydroxylase 1 (P3H1) and cyclophilin B (CyPB). Fibroblasts normally secrete about 10% of CRTAP. Most CRTAP mutations cause a null allele and lethal type VII OI. We identified a 7-year-old Egyptian boy with non-lethal type VII OI and investigated the effects of his null CRTAP mutation on collagen biochemistry, the prolyl 3-hydroxylation complex, and collagen in extracellular matrix. The proband is homozygous for an insertion/deletion in CRTAP (c.118_133del16insTACCC). His dermal fibroblasts synthesize fully overmodified type I collagen, and 3-hydroxylate only 5% of α1(I)Pro986. CRTAP transcripts are 10% of control. CRTAP protein is absent from proband cells, with residual P3H1 and normal CyPB levels. Dermal collagen fibril diameters are significantly increased. By immunofluorescence of long-term cultures, we identified a severe deficiency (10-15% of control) of collagen deposited in extracellular matrix, with disorganization of the minimal fibrillar network. Quantitative pulse-chase experiments corroborate deficiency of matrix deposition, rather than increased matrix turnover. We conclude that defects of extracellular matrix, as well as intracellular defects in collagen modification, contribute to the pathology of type VII OI.

Asunto(s)

RESUMEN

The predictive value of sperm chromatin integrity for pregnancy outcome following in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) was studied in 24 men attending a university-based assisted reproductive techniques laboratory using the flow cytometric sperm chromatin structure assay (SCSA). The SCSA is a measure of the susceptibility of sperm DNA to low pH-induced denaturation in situ. The mean percentage of spermatozoa in the neat sample demonstrating DNA denaturation was significantly lower in the seven men that initiated a pregnancy (15.4 +/- 4.6, P = 0.01) than in the 14 men who did not initiate a pregnancy (31.1 +/- 3.2). No pregnancies resulted if > or =27% of the spermatozoa in the neat semen sample showed DNA denaturation. These data demonstrate that SCSA parameters are independent of conventional semen parameters. Furthermore, the SCSA may allow physicians to identify male patients for whom IVF and ICSI will be unlikely to result in pregnancy initiation.

Asunto(s)

RESUMEN

The purposes of this study were to (1) describe the microenvironment in terms of oxygen concentration beneath the drapes of healthy subjects who were simulating patients undergoing minor surgical procedures with supplemental oxygen and to (2) evaluate the efficacy of using a scavenger system beneath the drapes. A convenience sample of 12 healthy volunteer subjects was studied in an ambulatory surgery center operating room, which was ventilated with 25 air exchanges per hour. The study was carried out in 2 parts. Each subject was supine, and oxygen was applied by a standard nondivided nasal cannula. The subjects were draped as routinely done for ophthalmic procedures. Oxygen concentrations were measured by using an Ohmeda Rascal II gas analyzer beneath the drapes and at the hypothetical surgical site with oxygen flow rates of 0, 1, 2, 3, and 4 L/min, allowing 5 minutes to elapse after a change in flow rate was made. Following a 10-minute break, the subjects were redraped, and the procedure was repeated using a scavenger system consisting of a suctioning system connected to wall suction at 170 to 190 mm Hg. Although the mean +/- SD oxygen saturation never fell below 95% (97.75% +/- 1.54%), mean +/- SD oxygen concentrations beneath the drapes were lower than normal room air concentrations (19.08% +/- 0.51%) when no oxygen was delivered to the patient. With supplemental oxygen and no scavenger system, oxygen concentrations beneath the drapes were consistently elevated (as high as 45% with 4 L/min) compared with normal ambient concentrations (21%) or with concentrations obtained at the surgical site (as high as 23.4%). With the scavenger system in place, mean +/- SD oxygen concentrations reached 34.08% +/- 5.52% beneath the drapes. Statistical analyses revealed that significantly higher oxygen concentrations occurred beneath the drapes with each incremental change in oxygen flow rate, and regardless of the oxygen flow rate used, oxygen concentrations beneath the drapes were significantly reduced with the use of the scavenger system.

Asunto(s)

Asunto(s)

RESUMEN

A plague (Yersinia pestis) epizootic spread through Gunnison's prairie dogs (Cynomys gunnisoni), and possibly other rodent species, in the Moreno Valley in north-central New Mexico between winter 1984-1985 and autumn 1987. We observed the progress of the epizootic and subsequent population recovery at four prairie dog towns within the valley during this period. At two towns (Midlake and Val Verde) the prairie dogs were marked prior to the epizootic. At two additional towns (Vega and South Entrance) prairie dogs were marked following the epizootic. In 1988, a second epizootic occurred at Vega. One hundred thirty-nine serum samples were collected from prairie dogs and other rodents and 1,750 fleas were collected from animals and burrows. Fleas infected with Y. pestis were collected from prairie dogs, deer mice (Peromyscus maniculatus), and thirteen-lined ground squirrels (Spermophilus tridecemlineatus). Prairie dog fleas included Oropsylla hirsuta, O. labis and O. tuberculata, deermouse associated fleas were Aetheca wagneri and Rhadinopsylla sectilis, and Oropsylla bacchi was associated with thirteen-lined ground squirrels. All of the above flea species were collected from prairie dog burrows. All rodent species shared some flea species. Thirteen-lined ground squirrels disappeared shortly before plague was identified in prairie dogs at Midlake. Meadow voles were rare following the epizootic at Vega in 1986, became abundant in 1987, and disappeared at the time of the second prairie dog epizootic in summer 1988. Although we collected serum from Gunnison's prairie dogs, thirteen-lined ground squirrels, deer mice, and meadow voles (Microtus pennsylvanicus), we identified elevated serum titers against Y. pestis only in Gunnison's prairie dogs. Prairie dog mortality at all towns affected by plague was in excess of 99%. Serum antibody titers indicate that more than 40% of the few prairie dogs left to establish colonies following epizootics survived plague infection.

Asunto(s)

RESUMEN

OBJECTIVE: To use double-label fluorescence in situ hybridization to evaluate a modified swim-up procedure that is purported to be effective for preconceptual sex selection. DESIGN: Controlled, blinded study. SETTING: University hospital laboratories. PATIENT(S): Donor males reporting for routine semen analysis. MAIN OUTCOME MEASURE(S): Percentages of X- and Y-bearing spermatozoa in neat semen and in two swim-up fractions, determined using double-label fluorescence in situ hybridization. RESULT(S): No clinically significant change from a 1:1 ratio was found in the distribution of X- or Y-bearing spermatozoa after double-label fluorescence in situ hybridization following a modified swim-up procedure and irrespective of the time (15, 30, 45, and 60 minutes) allowed for swim-up. CONCLUSION(S): Using fluorescence in situ hybridization, a modified swim-up procedure was evaluated for its purported ability to skew the relative percentages of X- and Y-bearing spermatozoa. No clinically significant change in the ratio of X- to Y-bearing spermatozoa was detected independent of time. Therefore, clinical application of this procedure should be strongly discouraged.

Asunto(s)

RESUMEN

Because butorphanol (Stadol), a synthetic morphinan compound, has been demonstrated in our laboratories to produce physical dependence and withdrawal symptoms in rats, we have hypothesized that butorphanol has rewarding properties indicative of abuse potential. To test this hypothesis, the effects of equimolar doses of butorphanol tartrate (0.5-5.0 micrograms) and morphine sulfate (0.8-8.0 micrograms) were assessed in inbred Lewis male rats using the conditioned place preference (CPP) paradigm. Unilateral microinjections (1 microl/inj) of saline or opioids were made into the ventral tegmental area (VTA). Microinjections of saline to controls were associated with both sides of modified Skinner boxes, whereas opioid injections were associated only with the white chambers (less preferred side to the naive animals). Opioids were administered alternating with saline in the drug-treated animals on alternating days. During eight conditioning sessions the rats learned to associate light and dark sides of the Skinner boxes with microinjections of opioids or saline, respectively. Although all doses of morphine induced significant preference over saline, only the higher doses of butorphanol (2.0-5.0 micrograms) produced significant conditioned place preference for the sides of the chambers associated with the drugs. These results suggest that, like morphine which is widely abused, butorphanol also has rewarding properties, and, therefore, further investigations regarding its abuse potential are necessary.

Asunto(s)

RESUMEN

From 1970 to 1991, 295 indigenous cases and one imported case of human plague were reported in the United States. Eighty-two percent of the total indigenous cases occurred in New Mexico, Arizona, and Colorado. Ninety-three percent of these cases had onset in the months of April through November. Most cases (89%) presented as bubonic or septicemic plague, or both. Cases were reported more frequently in males (58%), and male mortality exceeded that of females (17 versus 11%). Ground squirrels were the most frequently implicated sources of infection in cases associated with flea bites, and domestic cats were found to play an increasingly important role in transmission of disease to humans during these decades.

Asunto(s)

RESUMEN

Yersinia pestis possesses a unique gene (pla) encoding coagulase and fibrinolysin which is implicated in the transmission of plague by fleas. This gene is encoded on the highly conserved but poorly characterized 'pesticin' plasmid pKYP1. The role of the pKYP1-encoded gene, pla, in plague transmission was addressed by feeding fleas on blood containing avirulent Y. pestis strain EV76-6 and three derivatives of this strain (K10-2, K10-3, and K10-5) carrying Tn801 insertions in pKYP1. One of these mutant strains, K10-5, contains an insertion within the pla gene that eliminates both coagulase and fibrinolysin activities, whereas strains K10-3 and K10-2 retain both pla-associated phenotypes. After feeding, it was found that flea mortality at 4 d after infection associated with strain K10-5 (26%) was significantly lower than the mortality observed with other strains (53-64%). These results suggest that expression of the pla gene product may contribute to the deleterious effects of plague bacilli on fleas that have been associated with flea blockage and plague transmission. This increased mortality is not caused simply by an increased bacterial load in fleas containing pla+ bacteria because fleas ingesting pla+ strains contained no more bacteria by flea blot hybridization analysis than did those that ingested the pla- strain K10-5. It is anticipated that further work in this area will clarify the mechanism by which pla acts and will reveal additional genetic loci in the plague bacillus which are required for transmission by fleas.

Asunto(s)

RESUMEN

Sixteen healthy cats were fed a 6-wk-old laboratory mouse that had died of experimentally induced Yersinia pestis infection (strain NM77-538), to simulate oral exposure to plague. The cats were closely monitored after ingestion. Physical exams were performed and vital signs were recorded daily. Plague antibody titers and cultures of blood, throat, and oral cavity were performed daily. Complete blood counts and biochemistry panels were performed every 3 d. Complete necropsies were performed on any cats that died. Cats exhibited one of three responses following ingestion of one plague-infected mouse; they either died (6/16 or 38%), developed transient illness and recovered (7/16 or 44%) or showed no signs of illness (3/16 or 19%). A continual fever greater > 40 degrees C was associated with a poor prognosis. The highest antibody titers developed in the group that shed the plague bacillus over an extended period of time. Blood, throat, and oral cavity cultures were positive in 100% of the fatal cases. Throat cultures were positive in 75% of the exposed cats. In contrast to other carnivores, cats infected with Y. pestis exhibit bubo formation and pneumonic lesions similar to those seen in people with plague. Because of the potential transmission of Y. pestis from cats to people, development of a plague vaccine for cats may be warranted.

Asunto(s)

RESUMEN

Children of alcoholics (COAs) represent a population at risk for alcoholism as well as other physical, emotional, and social problems. This survey explored perceptions of North Carolina elementary and middle school teachers regarding roles and responsibilities in assisting COAs, their need for additional training specific to COAs, and their perceptions of school-based resources for helping COAs. Survey findings teachers generally are willing to assist COAs but need training regarding these children. Training is particularly appropriate for teachers who perceive a low incidence of COAs in their classrooms since these individuals' responses suggest the existence of barriers to effective COA assistance.

Asunto(s)

RESUMEN

Upholstery cotton treated with four different concentrations (0.25-2.0%) (2,500-20,000 ppm) of an aqueous permethrin solution, used as nesting material by white mice, was laboratory-tested against the potential plague vectors Oropsylla montana (Baker), Thrassis bacchi (Rothschild), and Orchopeas howardi (Baker) and found highly effective (P less than 0.001) for 1 yr. Similarly treated cotton gauze was tested under ambient and 75% RH and was found to be highly effective (P less than 0.001) in both environments for 1 yr. A separate test determined that the LD50 of permethrin-treated cotton was less than 10 ppm. Cotton tested with 0.5% permethrin and distributed under field conditions to cricetid rodents for use as nesting material was found to be highly effective (P less than 0.001 as a pulicide for greater than 4 mo when tested during winter in Larimer County, Colo. Permethrin-treated cotton was less successful in controlling fleas on cricetid rodents during the summer months in a New Mexico hyperendemic plague area.

Asunto(s)

RESUMEN

Permethrin, a pyrethroid insecticide, applied on two plots with a pressurized hand-held duster at mean rates of 2.3 and 4.0 g per burrow, was used to determine control levels for Oropsylla hirsuta fleas, a vector of bubonic plague, in black-tail prairie dog, Cynomys ludovicianus, burrows in northern Colorado during the summer of 1988. Burrows were sampled by "flagging" at day 0 and weeks 1, 3, 6, 9, and 12 to determine the mean number of fleas per burrow and percentage of burrows with at least one flea. The 4.0 g per burrow rate was highly effective (P less than 0.001) in controlling fleas for a period of 3 mo, whereas the 2.3 g per burrow rate was not.

Asunto(s)

RESUMEN

In this study, six insecticide dust formulations were laboratory-tested in soil mixtures ranging in concentration from 40 to 1,280 parts per million (ppm) against a proven vector of bubonic plague, Oropsylla montana (Baker). Pulicidal effects of the six insecticides, which included three organophosphates, two carbamates, and a pyrethroid, were compared by LD(50) values at both ambient and 75% RH. Permethrin (Pyraperm 455 dust), a pyrethroid with a LD(50) less than 40 ppm, demonstrated the most effective pulicidal action for the 13-wk trial period, followed in order by chlorpyrifos, bendiocarb, propetamphos, diazinon, and carbaryl.

Asunto(s)

RESUMEN

The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents.

Asunto(s)

RESUMEN

Human plague is a local or systemic flea-transmitted infection caused by Yersinia pestis. It is maintained in well established enzootic foci among wild rodents. This article discusses the clinical findings in plague, diagnosis, treatment, and prevention of plague, and management of contacts of human plague cases and of exposures to epizootic plague. Tularemia shares many features with plague but is widespread in animal and arthropod vector populations and essentially throughout the United States.

Asunto(s)

RESUMEN

In this study, 20 laboratory reared Onychomys leucogaster from a parental population that is naturally exposed to plague were each fed a white mouse that had been inoculated with Yersinia pestis. Three of the 20 O. leucogaster died, four survived with antibody titers against Y. pestis and 13 survived with no titer against Y. pestis. In contrast, when 20 O. leucogaster from a plague naive parental population were fed infected prey, seven died and 13 survived with no antibody titer against Y. pestis. Our results suggest another means by which O. leucogaster from populations that are naturally exposed to plague may acquire the disease.

Asunto(s)

RESUMEN

From 1983 to 1985, 463 serum samples from 11 species of mammals in Redwood National Park (RNP) (California, USA) were evaluated for antibodies to Yersinia pestis by the passive hemagglutination method. Yersinia pestis antibodies occurred in serum samples from 25 (36%) of 69 black bears (Ursus americanus), one (50%) of two raccoons (Procyon lotor), five (3%) of 170 dusky-footed woodrats (Neotoma fuscipes), and one (less than 1%) of 118 deer mice (Peromyscus maniculatus). Two hundred seventy-three flea pools, consisting of 14 species of fleas, were collected from small mammals and woodrat nest cups. Viable Y. pestis were not isolated from any of the flea pools. Significant between-year variations in the frequencies of seropositive bear or small mammal sera were not observed. A significantly higher frequency of plague antibodies was observed in bear sera taken during September collections. Frequencies of seropositive bear sera did not vary significantly by sex or age group of bears. Significant differences were not observed in the frequencies of seropositive small mammals by forest habitat type in which they were captured. This is the first report of Y. pestis infection in Redwood National Park, and the first detailed report of Y. pestis activity in a temperate rainforest.

Asunto(s)

Asunto(s)

RESUMEN

The laboratory-born progeny from two geographically distant populations of northern grasshopper mice (Onychomys leucogaster) were challenged with Yersinia pestis to determine their relative susceptibilities to plague. One of the O. leucogaster populations was associated with a known epizootic focus of the disease and was found to be nearly 2,000 times more resistant to mortality than were members of another population from an area historically free of plague. The ecology and omnivorous behavior of O. leucogaster appears to promote strong selection for resistance to plague in areas where they are naturally exposed.

Asunto(s)