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Investigates the first record of the root lesion nematode, Pratylenchus bolivianus Corbett, in England and Wales. Crop where the nematode is discovered; Host range of the nematode; Characteristics of the nematodes.

Geochemical mass balances were computed for water years 1992-1997 (October 1991 through September 1997) for the five watersheds of the U.S. Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) Program to determine the primary regional controls on yields of the major dissolved inorganic solutes. The sites, which vary markedly with respect to climate, geology, physiography, and ecology, are: Allequash Creek, Wisconsin (low-relief, humid continental forest); Andrews Creek, Colorado (cold alpine, taiga/tundra, and subalpine boreal forest); Río Icacos, Puerto Rico (lower montane, wet tropical forest); Panola Mountain, Georgia (humid subtropical piedmont forest); and Sleepers River, Vermont (humid northern hardwood forest). Streamwater output fluxes were determined by constructing empirical multivariate concentration models including discharge and seasonal components. Input fluxes were computed from weekly wet-only or bulk precipitation sampling. Despite uncertainties in input fluxes arising from poorly defined elevation gradients, lack of dry-deposition and occult-deposition measurements, and uncertain sea-salt contributions, the following was concluded: (1) for solutes derived primarily from rock weathering (Ca, Mg, Na, K, and H(4)SiO(4)), net fluxes (outputs in streamflow minus inputs in deposition) varied by two orders of magnitude, which is attributed to a large gradient in rock weathering rates controlled by climate and geologic parent material; (2) the net flux of atmospherically derived solutes (NH(4), NO(3), SO(4), and Cl) was similar among sites, with SO(4) being the most variable and NH(4) and NO(3) generally retained (except for NO(3) at Andrews); and (3) relations among monthly solute fluxes and differences among solute concentration model parameters yielded additional insights into comparative biogeochemical processes at the sites.

The investigation of contacts of tuberculosis (TB) cases is an essential part of Mississippi's comprehensive TB program. A case interview is initiated within 24 hours, and the concentric circle method is used to identify and evaluate contacts. High-risk contacts of pulmonary cases are located and evaluated within 10 days. A follow-up evaluation is conducted by a TB consultant to determine the need for additional tests. All pulmonary contacts receive a 12-week follow-up tuberculin skin test (TST) if the initial test is negative. Directly observed treatment for latent TB infection (LTBI) is offered to all children aged <15 years, human immunodeficiency virus positive persons and others deemed at high risk for developing active disease. Mississippi contact investigations in 1990-1998 identified 212 (0.7%) cases of TB, and 5608 (17.5%) contacts with LTBI. In that period, the proportion of cases with contacts identified averaged 99%, with a mean number of contacts per case of 15.4. At the same time, 95% of contacts completed an evaluation for active TB and LTBI. Among contacts <15 years of age, >96% have completed LTBI treatment annually since 1992. Cases and case rates in Mississippi have decreased annually during this period. Effective TB contact investigation yields immediate results by identifying other sources of TB transmission and preventing future transmission through appropriate treatment of contacts with LTBI.

Adolescents identified before the age of 13 (N = 320) as having exceptional mathematical or verbal reasoning abilities (top 1 in 10,000) were tracked over 10 years. They pursued doctoral degrees at rates over 50 times base-rate expectations, with several participants having created noteworthy literary, scientific, or technical products by their early 20s. Early observed distinctions in intellectual strength (viz., quantitative reasoning ability over verbal reasoning ability, and vice versa) predicted sharp differences in their developmental trajectories and occupational pursuits. This special population strongly preferred educational opportunities tailored to their precocious rate of learning (i.e., appropriate developmental placement), with 95% using some form of acceleration to individualize their education.

In 1994, an apparent outbreak of atypical genital ulcers was noted by clinicians at the sexually transmitted disease clinic in Jackson, Mississippi. Of 143 patients with ulcers tested with a multiplex polymerase chain reaction (PCR) assay, 56 (39%) were positive for Haemophilus ducreyi, 44 (31%) for herpes simplex virus, and 27 (19%) for Treponema pallidum; 12 (8%) were positive for > 1 organism. Of 136 patients tested for human immunodeficiency virus (HIV) by serology, 14 (10%) were HIV-seropositive, compared with none of 200 patients without ulcers (P < .001). HIV-1 DNA was detected by PCR in ulcers of 6 (50%) of 12 HIV-positive patients. Multivariate analysis indicated that men with chancroid were significantly more likely than male patients without ulcers to report sex with a crack cocaine user, exchange of money or drugs for sex, and multiple sex partners. The strong association between genital ulcers and HIV infection in this population highlights the urgency of preventing genital ulcers in the southern United States.

Infectious complications associated with electroconvulsive therapy (ECT) are extremely unusual. When five of nine patients undergoing ECT at one facility on June 20, 1996 developed Staphylococcus aureus bloodstream infection (BSI), an investigation was initiated. A retrospective cohort study, a procedure review, and observational and microbiologic studies were performed. A case was defined as any patient who had ECT at Facility A from June 1, 1995 through June 20, 1996 and developed S. aureus BSI <30 days after ECT. The post-ECT S. aureus BSI rate was significantly greater on the epidemic day than the pre-epidemic period, (i.e., June 1, 1995 through June 19, 1996) (5 of 9 vs 0 of 54 patients, P < 0.001). All patients during the study period received propofol before ECT. Case patients were more likely than noncase patients to have higher maximum temperature after ECT (median 103.9 degrees F vs 100.0 degrees F, P < 0.03) and a greater time from preparation of intravenous medications to infusion (median 2.1 vs 1.1 h, P = 0.01). All case-patient S. aureus isolates were indistinguishable by pulsed field gel electrophoresis. Our investigation suggests that the ECT-associated S. aureus BSIs were associated with infection control breaks, which possibly led to the extrinsic contamination of propofol. Prevention of propofol-associated infectious complications requires aseptic preparation and use immediately before infusion.

OmpT is a protease associated with the outer membrane of Escherichia coli and possesses a high degree of homology to the plasminogen activator, Pla, of Yersinia pestis. We show here that OmpT from intact cells can indeed activate plasminogen. Clinical specimens of E. coli were examined for protease activity and for the ompT gene. Few isolates (12%) were found to be positive for OmpT activity, whereas most (77%) carried the ompT gene and expressed the cloned protease gene. In this report we present evidence suggesting that the surface architecture of E. coli influences the activity of OmpT and that OmpT may be indicative of the pathogenic potential of the organism.

Although syphilis is frequently overlooked as a cause of ocular disease, it remains an endemic disease and its incidence is increasing. This article reports on four recent cases of ocular syphilis, including pseudoretinitis pigmentosa, chorioretinitis, and a rare presentation of an isolated retinal vasculitis involving both the arteries and the veins. Fundus photography, fluorescein angiography, and electrophysiologic testing are included. These cases show the diverse manifestations of ocular syphilis, which may involve any structure in the eye, and they demonstrate that atypical presentations are often encountered.

The following is a case report of a 61-year-old woman with a 10-year history of pemphigus vulgaris, successfully treated with steroids and cytotoxic agents. The patient developed severe herpes zoster ophthalmicus, complicated by a staph-indolent corneal ulcer. This case illustrates several of the many unfortunate ophthalmological complications that may develop in the immunocompromised patient.

Patients with contrived histories and/or self-induced physical abnormalities (Munchausen's syndrome) are often successful in deceiving physicians. We recently cared for four patients with ocular Munchausen's syndrome. Self-induced ocular manifestations included voluntary nystagmus, subconjunctival hemorrhages, chronic orbital emphysema requiring exenteration, corneal alkali burns, erosions and ulcerations, and abscesses of the periorbital area. Correct diagnoses of ocular Munchausen's syndrome were made only after extensive medical and surgical investigations. Suggestions for evaluation and treatment will also be discussed.

The binding sites for [125I]LHRH were characterized in membranes from the hypthalamus and the effect of estrogen on the binding characteristics was studied in ovariectomized female rats. The radioligand, [125I]LHRH, was found to bind specifically to membranes from the hypothalamus at a maximal level, with an optimal temperature of 0 degrees C and a pH between 7 and 8. The binding was enhanced by NaCl at a concentration of 0.1-0.2 M. The specifically bound [125I]LHRH was only displaced by LHRH, but not by sodium iodide (NaI), bovine serum albumin and other hormones, such as thyrotropin-releasing hormone, bradykinin, oxytocin, prolactin, luteinizing hormone and growth hormone. The divalent metal ions, copper (Cu2+) and mercury (Hg2+), inhibited the specific binding of [125I]LHRH completely, whereas magnesium (Mg2+) and calcium (Ca2+) caused a decrease in binding. As revealed from Scatchard plot analysis, the binding sites for [125I]LHRH in the hypothalamus had a dissociation constant of 0.40 +/- 0.03 microM and the maximum number of binding sites was 98.55 +/- 4.34 pmol/mg protein. Treatment of female rates (ovariectomized for 3 weeks) with 4 micrograms of estradiol benzoate caused a statistically significant decrease in the maximal number of binding sites without any significant effect on the dissociation constant. However, the direct addition of estradiol hemisuccinate to the membrane preparations had no statistically significant effect on the specific binding of [125I]LHRH. The present study provides the evidence that estrogen decreases the density of binding sites for [125I]LHRH in the hypothalamus in vivo.

A tear film aspirate, from the lower fornix of a 64-year-old man with the clinical diagnosis of a herpes simplex indolent corneal ulcer, was examined via a new, rapid immunoperoxidase staining technique. This 4-hour modified immunoperoxidase stain is both sensitive and specific for herpes simplex virus type 1. The corneal epithelial cells shed in the tear film from the indolent ulcer were strongly positive for herpes simplex type 1 viral antigen using this new technique. This case report supports the theory that the pathogenesis of indolent herpetic corneal ulcers involves both a hypersensitivity response to viral antigen and an active viral infection.

Six monkeys had prior systemic immunization followed by intraretinal challenge to each eye with Toxoplasma antigens. All eyes developed iridocyclitis, vitritis, and retinal edema, but no necrotizing retinochoroiditis. One-half of the eyes were then challenged with living organisms and the other one-half with Toxoplasma antigens. All eyes developed iridocyclitis, vitritis, and retinal edema, but no necrotizing retinochoroiditis. Four months later, the right eye of each monkey was challenged with living Toxoplasma organisms injected intraretinally. Each injected eye developed iridocyclitis, vitritis, and retinal edema 24 hours after injection, and all developed a retinal vasculitis 6 days after injection. One injected eye developed a papillitis. A subcutaneous booster of living Toxoplasma organisms in four of the monkeys failed to produce a reactivation of the iridocyclitis, vitritis, and vasculitis. These findings suggest that hyperimmunization provides protection against the development of a necrotizing toxoplasmic retinochoroiditis in nonhuman primates and that it may lead to retinal vasculitis and iridocyclitis. This study also serves as an animal model of retinal vasculitis in ocular toxoplasmosis.

To study the possibility of establishing a rapid diagnosis of herpes simplex keratitis, corneas of 10 rabbits, a total of 20 eyes, were inoculated with herpes simplex virus (HSV), type I, strain PH. Epithelial keratitis developed within three days of inoculation in all the animals used. Scraping of infected corneas were smeared and examined, using a modified indirect immunoperoxidase technic. One hundred percent of the smears prepared from these corneas demonstrated positive cells. Negative findings in corneas inoculated with adenovirus 19 suggest the specificity of the reaction. To test the possibility of blockage of staining by the presumed development of circulating endogenous anti-HSV I antibodies, the corneas of eight consecutive patients who presented to the Albany Medical Center Hospital with known recurrent dendritic keratitis also were scraped and stained, using a similar procedure. Positive cells present in each of these scrapings suggest against the blocking of this immunoperoxidase method by the development of circulating anti-HSV antibodies.

A gravely ill patient had Vibrio alginolyticus conjunctivitis develop, possibly from contact with seashell fragments. It is believed to be the first reported instance of ocular infection by this organism. Marine Vibrio organisms must be considered as potential sources of ocular infection in patients with direct or indirect exposure to salt water habitats, or in patients who are immunocompromised.