Hematologic malignancies during pregnancy

Most hematologic malignancies are rare during the childbearing years with the exception of Hodgkin's lymphoma. However, the continued spread of retroviruses, such as human immunodeficiency virus, in the heterosexual population may result in a substantial rise in viral-induced non-Hodgkin's lymphomas. Although pregnancy does not affect the natural course of these illnesses, adequate staging and therapy can be a difficult task. The obstetrician and the consultant hematologist/oncologist must weigh the benefit of immediate treatment while minimizing toxicity to the fetus.

Overuse of the indwelling urinary tract catheter in hospitalized medical patients

BACKGROUND

The indwelling urinary tract catheter (IUTC) is an important aspect of medical care. We studied the prevalence of the unjustified use of the IUTC in hospitalized medical patients and identified situations associated with its unjustified use.

METHODS

This prospective study involved 202 patients admitted to either the medical intensive care unit (n = 135) or the medical floors (n = 67) of a tertiary care university hospital who were catheterized during the hospital admission. An independent observer assessed the indication of initial catheterization by chart review and interview with the patient and the nurse. The need for continued catheterization was assessed daily by the same observer. The proportion of unjustified IUTC placement was determined using the study guidelines. Complications as a direct consequence of catheter use were recorded.

RESULTS

Of the 202 patients who were studied, the initial indication for the placement of an IUTC was found to be unjustified in 21% (95% confidence interval [CI], 15% to 27%). Continued catheterization was unjustified in 47% (95% CI, 42% to 57%) of 912 patient-days with IUTC studied. In the medical intensive care unit, 64% (95% CI, 58% to 70%) of the total unjustified patient-days with IUTC resulted from its excessively prolonged use for monitoring urine output. Urinary incontinence was found to be the major cause of unjustified initial ([52%] 95% CI, 32% to 74%) and continued ([56%] 95% CI, 50% to 62%) use of IUTC in the noncritical care areas. Catheter-related urinary tract infection requiring intravenous antibiotics or continuous bladder irrigation with amphotericin B was observed in 5% of the patients.

CONCLUSIONS

The IUTCs are significantly overused in hospitalized medical patients and careful attention to this aspect of medical care may reduce catheter-related complications by primary prevention.

Beta-lactamase inhibitor combinations

The beta-lactamase inhibitor combinations present a novel approach to the problem of beta-lactamase-induced resistance to antibiotics. These agents are derived from the generally safe beta-lactam class of antibiotics. They are all principally excreted through the kidneys and require dosage adjustment in the face of significant renal insufficiency. They show significantly increased activity against methicillin-sensitive S. aureus, H. influenzae, B. catarrhalis, and B. fragilis. The activity against Enterococcus, Pseudomonas, and most gram-negative bacilli, however, remains limited to that of the respective antibiotic component. Although shown to be clinically useful in a variety of clinical situations, they appear to be most useful for skin and soft tissue infections and lower respiratory tract infections as well as intra-abdominal and gynecologic infections caused by susceptible pathogens.

Twin autonomous bipartite nuclear localization signals direct nuclear import of GT-2

GT-2 is a DNA-binding protein with high target-sequence specificity toward functionally defined, positively acting cis elements in the rice phytochrome A gene promoter. Using immunocytochemical procedures, it is shown here that GT-2 is localized to the nucleus, consistent with a function in transcriptional regulation. Immunoblot and immunocytochemical analyses show that rice shoots contain higher levels of GT-2 protein than roots, and that no photo-induced changes in GT-2 abundance or spatial distribution are detectable in these tissues, a result consistent with the proposed constitutive activity of GT-2. In both shoots and roots, GT-2 protein is undetectable in meristematic tissue but becomes expressed at later stages of cellular development, consistent with a role in contributing to the pattern of phytochrome A gene expression. By transfecting protoplasts with a series of constructs containing deletion derivatives of GT-2 fused to beta-glucuronidase (GUS), followed by in situ localization of GUS activity, two independent, functionally active nuclear localization sequences (NLSs) have been identified in GT-2. One NLS resides within each of a pair of previously identified, spatially separate, trihelix motifs in the protein. Sequence inversion and alanine-scanning mutagenesis has identified residues within these NLSs necessary for nuclear localization. Each NLS contains two basic domains separated by 10 amino acids, conforming to the bipartite class of NLS involved in the targeting of numerous other nuclear localized proteins.

Experimental transmission of eastern equine encephalitis virus and Highlands J virus via semen of infected tom turkeys

Tom turkeys were experimentally inoculated with eastern equine encephalitis (EEE) virus or Highlands J (HJ) virus; semen was examined for presence of virus and ability to transmit infection by artificial insemination. Mild depression and inappetence were observed in tom turkeys inoculated with either EEE virus or HJ virus. Toms were viremic on days 1-2 postinoculation (PI), and virus was shed in semen on days 1-5 PI. Semen collected from EEE-virus-inoculated or HJ-virus-inoculated toms on days 1-2 PI and inseminated into turkey breeder hens transmitted the infection. EEE virus was detected in one of 10 hens after insemination with semen from EEE-virus-inoculated toms, and HJ virus was detected in three of 10 hens after insemination with semen from HJ-virus-inoculated toms. These results indicate that semen is a potential vehicle for transmission of EEE virus and HJ virus.

Assessment and initial management of the pregnant trauma patient

The pregnant trauma patient with a blunt or penetrating injury presents a unique and challenging clinical situation. Two patients must be treated simultaneously: the mother and fetus. The author reviews the assessment changes of pregnancy, which can both mask and mimic injury. The unique injuries that occur in this patient population are described, including abruptio placentae, preterm labor, fetomaternal hemorrhage, and uterine and fetal trauma. Successful resuscitation of the pregnant trauma patient requires early and frequent collaboration with the obstetrical staff. Within a team approach, the dual assessment of mother and fetus can render prompt identification and treatment of injuries. Diagnostic tests, including laboratory data, radiographic exams, and abdominal and obstetrical procedures, are reviewed.

Experimental infection of young broiler chickens with eastern equine encephalitis virus and Highlands J virus

Two-week-old broiler chickens were experimentally infected with either eastern equine encephalitis (EEE) virus or Highland J (HJ) virus. Mortality rates were 24/30 (80%) in EEE-virus-inoculated chickens and 2/30 (7%) in HJ-virus-inoculated chickens. Chickens inoculated with EEE virus exhibited severe depression and somnolence on days 1-6 postexposure (PE), with 17/30 birds dying during this period. After day 6 PE, EEE-virus-inoculated chickens exhibited abdominal distention, depression, and growth retardation, and an additional seven chickens died. Pathologic changes in EE-virus-inoculated chickens dying on days 1-6 PE consisted of multifocal necrosis in the heart and liver, as well as lymphoid depletion and necrosis in the thymus, spleen, and bursa of Fabricius. Ascites, pericardial effusion, and right ventricular dilatation of the heart were the predominant lesions in chickens dying after day 6 PE. No clinical signs were observed in sham-inoculated controls or in most HJ-virus-inoculated chickens. Ascites, pericardial effusion, and multifocal myocardial necrosis were observed in 2/30 HJ-virus-inoculated chickens that died or were euthanatized after development of clinical signs. These findings indicate that both EEE virus and HJ virus are pathogenic for young chickens.

Decreased egg production in turkeys experimentally infected with eastern equine encephalitis virus or Highlands J virus

Turkey breeder hens were experimentally infected with strains of eastern equine encephalitis (EEE) virus or Highlands J (HJ) virus previously isolated from turkey hens experiencing decreased egg production. Depression and inappetance were observed on day 1 postexposure (PE) in hens inoculated with either EEE virus or HJ virus, and egg production fell in each virus-inoculated group from approximately 75% to less than 20% within 2-3 days PE. Egg production remained depressed (less than 20%) for 15 days in EEE-virus-inoculated hens and for 7 days in HJ-virus-inoculated hens. EEE virus and HJ virus were recovered from various tissues on days 1-5 PE, and virus was detected in eggs laid on days 2-5 PE. The findings of this study confirm that EEE virus and HJ virus are potential causes of decreased egg production in turkey breeder hens.

Molecular genetic approaches to leaf development: Knotted and beyond

Molecular genetics provides a promising alternative to other experimental approaches for furthering our understanding of the mechanisms controlling leaf development. We investigated the molecular basis of dominant Knotted (Kn1) mutations in maize, which cause cells associated with the lateral veins of the leaf blade to acquire characteristics of sheath or auricle and sporadically form outgrowths called knots. The kn1 gene encodes a homeodomain, a DNA-binding domain shared by many transcription factors that regulate developmental processes in animals and fungi. In normal plants, the expression of kn1 is confined to the shoot apex, but in Kn1 mutants, the gene is also expressed ectopically in the veins of developing leaves, apparently causing cells to change their developmental fates. The kn1 gene may function in the shoot apex of normal plants to promote indeterminate growth. Consistent with this hypothesis, when kn1 is expressed constitutively at high levels in the leaves of transgenic tobacco, shoots are formed on the leaf surface. Thus, our results indicate that while the kn1 gene may normally have no function in leaf development, it can alter the development of maize and tobacco leaves when it is expressed in the leaf inappropriately. Genes that normally play a role in leaf development are more likely to be defined by recessive mutations that alter leaf morphogenesis and histogenesis. Key words: leaf development, molecular genetics, Knotted.

Mutation in the DNA mismatch repair gene homologue hMLH1 is associated with hereditary non-polyposis colon cancer

The human DNA mismatch repair gene homologue hMSH2, on chromosome 2p is involved in hereditary non-polyposis colon cancer (HNPCC). On the basis of linkage data, a second HNPCC locus was assigned to chromosome 3p21-23 (ref. 3). Here we report that a human gene encoding a protein, hMLH1 (human MutL homologue), homologous to the bacterial DNA mismatch repair protein MutL, is located on human chromosome 3p21.3-23. We propose that hMLH1 is the HNPCC gene located on 3p because of the similarity of the hMLH1 gene product to the yeast DNA mismatch repair protein, MLH1, the coincident location of the hMLH1 gene and the HNPCC locus on chromosome 3, and hMLH1 missense mutations in affected individuals from a chromosome 3-linked HNPCC family.

Experimental infection of young turkeys with eastern equine encephalitis virus and highlands J virus

Depression, somnolence, and increased mortality were observed in 2-week-old turkeys inoculated intramuscularly with either eastern equine encephalitis (EEE) virus or Highlands J (HJ) virus. Mortality rates in EEE virus- and HJ virus-inoculated turkeys were 7/30 (23%) and 9/30 (27%), respectively; no sham-inoculated controls died. Both EEE virus- and HJ virus-inoculated turkeys developed viremia that lasted 2 days; peak mean titers were 5.5 and 3.2 log10 plaque-forming units per ml of blood, respectively. Pathologic changes in both EEE virus- and HJ virus-inoculated turkeys consisted primarily of multifocal necrosis in the heart, kidney, and pancreas, and lymphoid necrosis and depletion in the thymus, spleen, and bursa of Fabricius. The findings indicate that EEE virus and HJ virus are pathogenic for young turkeys.

A dominant mutation in the maize homeobox gene, Knotted-1, causes its ectopic expression in leaf cells with altered fates

Dominant mutations of the Knotted-1 (Kn1) homeobox gene of maize alter the differentiation and growth of cells associated with leaf veins. By analyzing Kn1 transcripts and KN1 protein, we show that the gene is not expressed at high levels during the development of wild-type leaves. Instead, Kn1 is expressed in apical meristems of vegetative and floral shoots, and is downregulated as leaves and floral organs are initiated. Kn1 is also expressed in relatively undifferentiated cells within developing vascular bundles, as well as ground tissue, in immature, unelongated axes of wild-type vegetative and floral shoots. In Kn1-N2 mutant plants, quantitative, but not qualitative differences are apparent in Kn1 transcripts and KN1 protein, consistent with previous observations that dominant Kn1 mutations map to non-coding regions of the gene. Kn1 is expressed ectopically in vascular bundles within developing mutant leaves in a pattern that correlates with the phenotypic alterations produced by the Kn1-N2 mutation. Thus, Kn1 apparently alters the fates of leaf cells in which it is ectopically expressed from an early stage of leaf development. Based on these observations, we hypothesize that Kn1 functions in its wild-type context as a regulator of cell determination.

Oligohydramnios and megacolon in a fetus with vesicorectal fistula and anal-urethral atresia: a case report

Severe oligohydramnios and extremely dilated bowel filled with hyperechogenic material floating in fluid were the ultrasonographic findings in a fetus at 27 weeks' gestation. Vesicorectal communication and urethral-anal atresia permitted urine to empty into the colon, causing megacolon, oligohydramnios, and markedly increased intraabdominal pressure resulting in pulmonary hypoplasia.

Calcium homeostasis in pregnant women receiving long-term magnesium sulfate therapy for preterm labor

OBJECTIVES

The hypothesis of this study is that calcium homeostasis and bone mineralization are altered in pregnant women receiving long-term therapy with magnesium sulfate as compared with similar women not receiving magnesium sulfate to control preterm labor.

STUDY DESIGN

Thirty-nine women between 24 and 32 weeks' gestation, matched for age, race, and duration of bed rest, were enrolled. Indices of calcium homeostasis in serum and urine were measured serially, and bone mineralization of the distal radius was measured at 1 and 11 weeks post partum.

RESULTS

Magnesium therapy was administered for a mean duration of 26 +/- 14 days and a cumulative dose of 1405 +/- 963 gm. Serum concentrations of magnesium, phosphorus, and parathyroid hormone increased and those of calcium decreased from baseline values in the magnesium sulfate group and remained uniform throughout the 3-week investigation. The serum magnesium, phosphorus, parathyroid hormone, and calcium concentrations in the control group were unchanged during the study and differed significantly from those in the magnesium sulfate group (p < 0.001). Urinary output of magnesium, calcium, and copper was significantly greater in the magnesium sulfate group than in the control group throughout the study. Urinary losses of calcium in the magnesium sulfate group, approximately 800 to 900 mg/day, were substantial. Although radius bone density 1 week post partum did not differ between groups, the change in bone density from 1 to 11 weeks post partum was significantly lower in the magnesium sulfate group than in controls.

CONCLUSIONS

These data suggest that calcium homeostasis is altered during and after long-term magnesium sulfate therapy. The marked, prolonged urinary calcium losses may affect maternal bone mineralization.

Indomethacin for the treatment of symptomatic leiomyoma uteri during pregnancy

Pain secondary to carneous degeneration is the most common complication of leiomyoma uteri during pregnancy. Conventional therapy utilizing bed rest and parenteral narcotic analgesics may often be ineffective. We retrospectively reviewed seven cases of degenerating fibroids complicating pregnancy where the prostaglandin synthetase inhibitor, indomethacin (25 mg orally every 6 hours), was used to treat symptoms of pain. In all cases, relief of symptoms was achieved within 48 hours of initiation of therapy. Two patients required a second course of therapy, and one patient required a third course. Mean duration of therapy was 12 days. One fetus developed transient constriction of the ductus arteriosus and transient oligohydramnios. Two pregnancies aborted, one at 22.9 and one at 22.3 weeks; however, no perinatal complications were directly attributable to indomethacin. The five term deliveries were of healthy normal infants. These retrospective data suggest that indomethacin may be effective in the treatment of pain associated with degenerating uterine leiomyomas in pregnancy.