Biomedical subjects
Publications and source records attributed to J L Davis.
Gastric cancer is unusual during pregnancy. Also, because of the physiologic changes that occur with pregnancy, it is rare to see a worsening of peptic ulcers during pregnancy. A patient with an exacerbation of peptic ulcers presented with gastric carcinoma during pregnancy.
Recent hypotheses suggesting a critical role of glutamate receptors in hippocampal long-term potentiation and memory processing suggested a closer examination of this transmitter's effect on memory processing in an in vivo setting. New pharmacological antagonists allow for a separation and examination of various glutamate receptors and their role in memory processing. Mice were trained on a shock avoidance learning paradigm and injected intracerebroventricularly after training with agonists and antagonists of various classes of glutamate receptors. Retention was tested 1 week after training. N-Methyl-D-aspartate (NMDA) receptor agonists enhanced retention in a dose-dependent manner. The enhancement of retention by the non-NMDA agonist kainic acid and quisqualic acid was dose-dependent. L-Glutamic acid, but not D-glutamic acid, enhanced retention. Both NMDA and non-NMDA receptor antagonists produced dose-dependent impairment of retention for footshock training. Administration of the antagonists 24 h after training did not impair memory retention.
A 37 year old woman presented with a bilateral vitritis. 4 months previously, she had developed in her left eye a necrotizing retinitis compatible with acute retinal necrosis (ARN). A trial of Acyclovir was unsuccessful as were systemic steroids. Over the following 2 months the vitritis worsened. The patient underwent a diagnostic vitrectomy revealing the presence of a large B-cell lymphoma with a predominance of lambda light chains.
A strong association with HLA antigens DR4, DRw53, and Bw54 has previously been reported among Japanese patients with Vogt-Koyanagi-Harada disease (VKH) and sympathetic ophthalmia (SO). In the United States, no firm association between HLA-A or -B loci and VKH has been found previously; testing for HLA-DR loci has not been performed to date. The authors performed HLA typing of 23 American patients with VKH and 8 patients with SO. When VKH patients were compared with racially matched controls without disease and patients with other types of uveitis, strong associations with HLA-DR4 and HLA-DRw53 were found. The strongest associations observed in this sample were with HLA-DQw3, an antigen which is in positive linkage disequilibrium with DR4, and with the HLA-DR4/DQw3 haplotype. The small number of patients with SO precluded statistical analysis; however, similar HLA associations were noted. The patients also were questioned regarding their ancestry. The anecdotal association of VKH with American Indian ancestry was confirmed. It appears that the ethnoracial association may be explained by HLA type. One possible explanation for identical HLA associations in two diseases with different precipitating events yet similar ocular manifestations is development of an altered immune response to exogenous microbial antigen with subsequent autoimmunity. Further definition of the genetic susceptibility to VKH and SO may help define the pathophysiology of both diseases and allow the prediction of which patients are at increased risk for SO.
Explore the source record for details and available documents.
Uterine leiomyomas are associated with various complications during pregnancy. During a 2-year period, pregnant women with a history of leiomyomas were referred to our antenatal testing unit for ultrasound evaluation. Eighty-five patients were found to have single or multiple leiomyomas by ultrasound examination. The size (total leiomyoma volume), number, and location of the leiomyoma(s) were ascertained. Each woman with leiomyoma(s) was matched by age, race, and parity with one without leiomyomas. Both groups were followed throughout pregnancy, and outcomes were compared. Size, number, or location of the leiomyoma had no influence on outcome. Student t test indicated a significantly (P less than .01) lower mean gestational age at the time of delivery in women with leiomyomas.
Explore the source record for details and available documents.
The present study was conducted to determine whether triplet pregnancies are associated with a significantly worse perinatal outcome than twin pregnancies. Maternal and neonatal outcome was evaluated in 15 triplet and twin pregnancies that were matched for maternal age, race, type of medical insurance, delivery mode, parity, and history of previous preterm delivery. Preterm labor occurred significantly more often in triplet than in twin gestations (80 versus 40%), as did preterm delivery (87 versus 26.7%). Triplets had a significantly lower mean birth weight (1720 versus 2475 g) and gestational age at delivery (33 versus 36.6 weeks). In addition, 53.3% of triplet pregnancies but only 6.7% of twin pregnancies had one or more neonates with intrauterine growth retardation. Discordancy also occurred more frequently in triplets than in twins (66.7 versus 13.3%). The mean averaged neonatal hospital stay was significantly higher in triplets (29 versus 8.5 days), and triplets had a fivefold increased risk of requiring neonatal intensive care as compared with twins. However, there were no significant differences between the groups in maternal morbidity or major neonatal complications such as respiratory distress syndrome or intraventricular hemorrhage. We believe that these data will be useful in counseling patients with respect to the anticipated perinatal outcome of triplet pregnancies.
1. Although health newsletters are a frequent component of worksite health promotion programs, they vary considerably in distribution, format, and content. Such variety highlights the many options involved with this particular medium of health promotion. 2. The newsletters analyzed ranked highly in terms of attention catching potential and usefulness to employees. In addition, content strongly reflected an emphasis on prevention and healthy lifestyle habits. 3. Occupational health nurses must carefully consider advantages and disadvantages before deciding whether to use an outside vendor or produce the newsletter in-house, considering staff and time constraints in producing an effective newsletter. 4. The occupational health nurse is in a unique position to plan content and reinforce health messages that the newsletter presents, allowing for more effective interaction with the employees for whom the newsletters are designed.
To determine whether the biophysical profile would be a valuable intrapartum addition to fetal heart rate monitoring in predicting umbilical arterial acid-base status at delivery, 95 patients at term had serial studies during labor and umbilical artery blood gas analysis. There was no significant association between biophysical profile score and cord blood pH, nor was there a difference in scores between the acidemic and nonacidemic groups. Of the five components of the initial biophysical profile, only a nonreactive nonstress test (NST) was associated with both pH 7.20 or less (P = .019) and metabolic acidemia (P = .016). None of the individual variables of the final examination correlated with a pH of 7.20 or less. However, a nonreactive NST was associated with metabolic acidemia (P = .03), as was the presence of breathing (P = .03). Of the ten infants with pH 7.20 or less, eight had an initial and five had a final biophysical profile score of 8 or higher. Of the five whose pH was less than 7.15, four had an initial and three a final score of 8 or more. Finally, of the five with metabolic acidemia, four had an initial and two a final score of 8 or higher. Half of the acidemic fetuses had final biophysical profile scores of 8 or higher, suggesting that this score in labor is not reliable to rule out acidemia at delivery.(ABSTRACT TRUNCATED AT 250 WORDS)
Eighteen pony foals inoculated with 1,500 +/- 109 infective Parascaris equorum eggs were given 0.02 ml of ivermectin vehicle (liquid)/kg of body weight, PO, (control); 0.2 mg of ivermectin paste/kg, PO; or 0.2 mg ivermectin liquid/kg, PO, on postinoculation day (PID) 28. Foals were euthanatized on PID 42, and the small intestinal contents were examined for P equorum larvae. The mean number of fourth-stage P equorum larvae in foals treated with ivermectin paste and liquid were 3.5 and 6, respectively. Significantly (P less than 0.01) higher mean numbers of larvae (1,250) were detected in foals treated with ivermectin vehicle. Larvae recovered from foals treated with ivermectin vehicle were of significantly (P less than 0.002) longer mean length than those from foals treated with ivermectin paste or liquid. Gross examination of lungs and liver revealed similar pathologic changes from the migration of P equorum in all foals. Adverse reaction to treatment was not observed.
We studied two patients, one with histologically confirmed endogenous bacterial retinitis associated with the acquired immunodeficiency syndrome and a second with ophthalmoscopically identical findings who also responded to antibiotic treatment. Both patients had focal, discrete patches of retinitis that enlarged slowly over weeks and ultimately accumulated large amounts of subretinal fluid and retinal exudate. One patient underwent retinal biopsy after systemic and vitreous cultures were negative. Histopathologic sections showed necrotic retina infiltrated with multiple histiocytes containing intracytoplasmic, iodine-positive, pleomorphic, encapsulated bacterial forms. The organism was not grown from the retinal biopsy specimen. Treatment with antibiotics resulted in improved vision in both patients. Our results indicate that endogenous bacterial infection should be considered in the differential diagnosis of retinitis associated with the acquired immunodeficiency syndrome.
The chronic and relatively acute changes in blood volume that occur during pregnancy and post partum may be associated with alterations in the content of atrial natriuretic factor in the atria. We measured the concentration of atrial natriuretic factor in the right and left atria of virgin, pregnant, and postpartum Sprague-Dawley rats by radioimmunoassay as well as the concentration of atrial natriuretic factor in the atria and plasma of term pregnant rats on a high-salt diet. Neither right nor left atrial concentrations of atrial natriuretic factor were elevated during pregnancy in animals on a normal diet, but both were increased during the first 2 days after delivery. Term pregnant rats on a high-salt diet showed a small increase in atrial natriuretic factor levels in the left atria only, without any change in plasma atrial natriuretic factor levels. We conclude that relatively acute changes in fluid and electrolyte balance are more likely than chronic ones to be associated with alterations in atrial natriuretic factor concentrations in the atria.
Patients with specific granule deficiency (SGD) develop recurrent severe bacterial skin infections. Neutrophils from patients with SGD are deficient in lactoferrin (Lf), an antimicrobial protein commonly found in many mucosal secretions. Unstimulated and stimulated nasal secretions, saliva, and tears were collected from a patient with SGD and from normal control subjects and were analyzed for Lf. The secretions from the patient contained normal values of Lf, suggesting that the glands secrete Lf from a source other than neutrophils. Immunohistochemical staining of normal nasal mucosa demonstrated that Lf is localized within serous submucosal gland cells and that neutrophils are not normally observed in the nasal mucosa. These findings suggest that glandular tissues produce and locally secrete Lf by processes that are independent of neutrophil degranulation.
Intrauterine pressure was measured in three cyclic and two postpartum mares. Pressure was recorded using a catheter tip pressure transducer. The transducer was passed transcervically into the uterus.. In cyclic mares recordings were started on Day 1 of estrus and continued daily until ovulation as well as on Days 1 and 8 of diestrus. In postpartum mares recordings were started within 48 h after foaling and continued until the mares ovulated. The intrauterine pressure changes in postpartum mares was also recorded on Days 1 and 8 of diestrus. Spontaneous uterine contractions were recorded in cyclic mares for 30 min and in postpartum mares for 10 min. Induced uterine motilities were recorded for 30 min in both groups after the administration of oxytocin (40 USP, i.v.). Total area under the contraction curve in a 10-min period was used as a uterine motility quantitating unit. All mares demonstrated uterine contractions during estrus and diestrus. All mares demonstrated significant responses to oxytocin during estrus and diestrus. It appears that estrogen priming is not necessary for a significant uterine response to oxytocin.
Today is a challenging time for hospitals and nurse managers. Times of nursing shortage and the presence of more critically ill patients demand creative strategies. A clinical ladder helps managers hire and retain nurses. More importantly, it encourages perioperative nurses to advance their skills, making them better prepared to care for the seriously ill surgical patient in a safe, effective, and efficient manner.
The unique pathogenesis of lentiviral infections in humans and ruminant animals may be explained, in part, by the complex mechanisms regulating transcription and translation of their viral genes. This report demonstrates that a visna virus-encoded protein transactivates viral gene expression. A 1.4-kilobase cDNA clone encodes two distinct proteins with apparent molecular masses of 21.5 and 10 kDa. We demonstrate that the 10-kDa species is the visna virus transactivating (Tat) protein; the other species may be analogous to the rev (formerly art or trs) gene product of human immunodeficiency virus.
Several therapeutic and diagnostic techniques involve injection of radioactive material into the peritoneal cavity. Estimation of the radiation dose to the surface of the peritoneum or to surrounding organs is hampered by the lack of a suitable source region in the phantom commonly used for such calculations. We have modified the Fisher-Snyder phantom to include a region representing the peritoneal cavity which may be employed to estimate such radiation doses. A geometric model is described which is coordinated with the existing organ regions in the phantom. Specific absorbed fractions (derived by Monte Carlo techniques) for photon emissions originating within the cavity are listed. Photon S-values for several radionuclides which have been administered intraperitoneally are shown. Dose conversion factors for electrons irradiating the peritoneal cavity wall, from either a thin plane or volume source of activity within the cavity, are also given for several nuclides.