Adhesion in vitro and in vivo associated with an adhesive antigen (F41) produced by a K99 mutant of the reference strain Escherichia coli B41.

A K99-negative mutant of the K99 reference strain Escherichia coli B41 (O101:K99) was isolated (strain B41M). It did not react with OK antiserum to a K12 K99+ recombinant or with OK antiserum to K99-positive organisms from the O8, O20, or O64 serogroups, but it did react with OK antiserum to K99-positive organisms from the O101 and O9 serogroups. The mutant hemagglutinated sheep erythrocytes and attached in vitro to calf enterocytes when cultured at 37 degrees C but not when grown at 18 degrees C. Attachment was mannose resistant but susceptible to heating and formaldehyde. These properties were associated with the presence of fimbriae. The isolated hemagglutinin migrated to the anode in immunoelectrophoresis experiments, competitively inhibited attachment of strain B41M to calf enterocytes, and could be demonstrated adhering to these cells in vitro by indirect immunofluorescent staining. The anionic hemagglutinin is referred to provisionally as F41. Germfree piglets infected with strain B41M developed diarrhea within 16 h. Scanning electron microscopy showed groups of bacteria adherent to the microvilli of villous enterocytes. Indirect immunofluorescent staining demonstrated the presence of F41 antigen in vivo.     

Fast, anticipatory smooth-pursuit eye movements appear to depend on a short-term store

Anticipatory smooth pursuit before the expected appearance of a moving target can reduce the initial retinal blur caused by the 100-ms delay of visual feedback. Humans, though, can only voluntarily generate smooth velocities up to about 5°/s without a moving target. However, previous experiments have shown that repetitive brief presentations of a moving target every few seconds appear to charge an internal store, the contents of which can later be released to generate higher velocity anticipatory movements. This store’s longevity was assessed here by repetitively presenting a moving target for 500 ms at different known intervals up to 7.2 s. Target motion at 25°/s or 50°/s was tested, with presentations in alternate directions or the same direction. Anticipatory velocity, measured 100 ms after target onset, decreased with increasing interval for all target motion conditions. A decrease was still seen when accurate timing cues were given before each presentation, suggesting that the drive for anticipatory pursuit is held in a short-term store lasting a few seconds which can enhance the low velocities produced by volition alone. The results also demonstrate that high-velocity anticipatory pursuit helps to overcome the temporal delays in the system and allows target velocity to be matched at an earlier time. Received: 27 August 1997 / Accepted: 22 December 1997     

Diagnosis of molar pregnancy and persistent trophoblastic disease by flow cytometry.

Histopathological assessment and flow cytometric analyses were carried out on 32 placentas (representative of each trimester) and 88 molar pregnancies. Three first trimester placentas were triploid, and the remaining 29 placentas were diploid. Of the 88 cases originally diagnosed as molar pregnancies, 26 were triploid (two complete moles, 20 partial moles, and four hydropic abortions); 59 were diploid (46 complete moles, 10 partial moles, three hydropic abortions); one was tetraploid (partial mole); and two were DNA aneuploid (one partial mole, one complete mole). A significantly increased hyperdiploid fraction (a measure of cell proliferation) was detected in diploid complete moles (p less than 0.0001) and cases of persistent trophoblastic disease (p less than 0.001) when compared with diploid placentas and diploid partial moles. All seven cases of established persistent trophoblastic disease, for which follow up was available, were diploid and showed high hyperdiploid fractions within the range for diploid complete moles. These findings suggest that flow cytometric DNA measurements may be an important aid in the diagnosis of molar pregnancy. The high degree of cell proliferation found in this study may explain the premalignant potential of complete hydatidiform moles.     

Bronchocentric granulomatosis: a complication of allergic bronchopulmonary aspergillosis.

Hypersensitivity to the fungal antigens of Aspergillus fumigatus may result in a spectrum of immune injury collectively known as allergic bronchopulmonary aspergillosis (ABPA). This report describes a 14-yr-old boy who presented clinical findings consistent with ABPA,including a history of asthma, blood eosinophilia, serum precipitins, and IgE antibodies to Aspergillus fumigatus. Sputum Aspergillus, pulmonary infiltrates, and dual types I and III skin reactions to Aspergillus fumigatus were observed also. Pathology of the resected right upper lobe revealed severe bronchial destruction with the findings of bronchocentric granulomatosis. Noninvasive septate fungal hyphae compatible with Aspergillus were identified. Cultures from sputum and surgical specimens grew Aspergillus and Mycobacterium intracellulare avium. The PPD-B (purified protein derivative-Batty) intradermal skin test produced a 6 mm induration (PPD-S was negative). The patient's condition has been well controlled with prednisone and several antituberculous drugs. In addition, inflammatory and immunologic parameters have begun to return to normal. The relationship between ABa and the atypical mycobacterial infection is not clear. The association of ABPA with the severe bronchial destruction seen in bronchocentric granulomatosis is emphasized to alert physicans to this serious sequelae of ABa seen in the asthmatic.     

Precursor lesions of ovarian epithelial malignancy

Most ovarian carcinomas arise from the mesothelial surface lining of the ovaries, or from invaginations of this lining into the superficial ovarian cortex to form cortical inclusion cysts. The native ovarian surface mesothelium is of an 'uncommitted' phenotype, and has potential to modulate to epithelial or mesenchymal phenotypes in response to signals such as those associated with ovulation. The exposure of the mesothelial lining of an inclusion cyst to the ovarian stromal microenvironment may be responsible for the phenotypic change to Müllerian epithelium so commonly seen in these cysts. Müllerian metaplasia is usually to a serous phenotype, and it is possible that undefined molecular events occurring in an inclusion cyst that has undergone Müllerian metaplasia may initiate neoplastic change in these cysts. This may be the developmental pathway of most invasive serous carcinomas. Occasional rare cases of ovarian intraepithelial neoplasia, manifested by epithelial atypia in an inclusion cyst or on the surface epithelium without invasive carcinoma, are identified histologically. Serous borderline tumours represent a separate category and in most cases probably do not progress to frank carcinoma. Mucinous carcinomas may in some cases have arisen from pre-existing benign and borderline mucinous tumours. Endometriosis of the ovary is associated with genetic abnormalities and is frequently found in association with clear cell and endometrioid carcinomas, suggesting that in many cases these latter two types of carcinoma may have arisen directly from endometriotic deposits. Ovaries removed prophylactically from women with a family history of ovarian carcinoma or with a mutation in one of the genes predisposing to ovarian carcinoma should be processed in their entirety, and examined closely not just for obviously neoplastic lesions, but also for more subtle morphological abnormalities of the surface epithelium or the epithelium lining cortical inclusion cysts.     

Concomitant renal revascularization in patients undergoing aortic surgery

Sixty-three patients who underwent renal revascularization at the time of aortic surgery were retrospectively reviewed. These patients had significant renal artery stenosis in addition to either severe aortoiliac occlusive disease or aortic aneurysmal disease. Fifty-eight patients were hypertensive, whereas five patients were normotensive and these renal lesions were treated prophylactically. The operative mortality rate was 3%. Despite lack of selectivity in these patients with diffuse atherosclerosis, 60% (35 of 58) of the patients with hypertension could be classified as either "cured" or "improved." Patients with bilateral renal artery involvement and moderate azotemia were noted to improve with respect to renal function postoperatively. No patient has required chronic dialysis at a mean follow-up period of 22.6 months. Simultaneous aortic and renal artery surgery may be performed with low morbidity and mortality rates and produce a gratifying improvement in hypertension. Renal functional improvement and perhaps preservation of renal mass may be anticipated in selected patients.     

The radioprotector WR1065 reduces radiation-induced mutations at the hypoxanthine-guanine phosphoribosyl transferase locus in V79 cells

N-(2-mercaptoethyl)-lt3-diaminopropane (WR1065) protects againstradiation-induced cell killing and mutagenesis at the hypoxanthine-guaninephosphoribosyl transferase (HGPRT) locus in V79 Chinese hamsterhing fibroblast cells. At a concentration of 4 mM, WR1065 wasfound to be effective in protecting against radiation-inducedcell lethality only if present during irradiation, e.g., a dosemodification factor (DMF) of 1.9. No protective effect was observedif the protector was added within 5 min after irradiation or3 h later, e.g., DMFs of 1.0 and 1.1, respectively. The effectof WR1065 on radiation-induced mutation, expressed as resistanceto the cytotoxic purine analogue 6-thioguanine (HGPRT), wasalso investigated. In contrast to the treatment-schedule dependencefor protection by WR1065 against cell killing, this agent waseffective in reducing radiation-induced mutations regardlessof when it was administered. Following a dose of 10 Gy of ⁶⁰Co-rays, the mutation frequencies observed per 10⁶ survivors were77 ± 8, 27 ± 6, 42 ± 7, and 42 ±7 for radiation only, and WR1065 present during, immediatelyafter, or 3 h after irradiation. These data suggest that althougha segment of radiation-induced damage leading to reproductivedeath cannot be modulated through the postirradiation actionof WR1065, processes leading to the fixation of gross geneticdamage and mutation induction in surviving cells can be effectivelyaltered and interfered with leading to a marked reduction inmutation frequency.     

Two screening instruments for collecting alcohol-related information from expectant mothers and fathers: Testing the reliability of the Parent Alcohol Screening Questionnaire and the Social Support for an Alcohol-Free Pregnancy Questionnaire

The aim is to test the reliability of two alcohol screening instruments: (1) The Parent Alcohol Screening Questionnaire (PASQ5), and (2) the Social Support for an Alcohol-free Pregnancy (SSAFP) questionnaire. This is a cohort study from the south of Sweden using repeated surveys during pregnancy. To examine if responses differed according to different data collection methods, two cohorts consisting of 289 expectant mothers and 141 fathers completed the PASQ5 both verbally (weeks 6–7) and in writing (week 12) within regular antenatal visits. One of the cohorts (n = 137/64) also completed the SSAFP in week 12 and later in week 33. The third cohort, consisting of 179 and 133 expectant mothers and fathers, respectively, completed the PASQ5 and the SSAFP twice in late pregnancy (week 31 + 33). Eight of 10 items in the PASQ5 were stable for both expectant mothers and expectant fathers when comparing verbal versus written-delivered formats. Eight of 10 questions in the PASQ5 were stable when assessing the items in a test–retest analysis in late pregnancy for expectant mothers and nine of 10 questions were stable for fathers. The SSAFP items showed high internal consistency (0.86) for expectant mothers and excellent internal consistency (0.94) for expectant fathers. Most SSAFP items (17 of 21 for expectant mothers and 18 of 22 for expectant fathers) were also stable in a test–retest scenario in late pregnancy. Both the PASQ5 and SSAFP are reliable tools and may be helpful for clinicians who aim to have a deeper dialogue about alcohol consumption during pregnancy. These tools may also be helpful for researchers aiming to better understand a person's changes in alcohol intake and/or their social support network.     

Argentaffin and argyrophil reactions and serotonin content of endocrine tumours.

Sixty carcinoid tumours were tested in a retrospective study with an immunoperoxidase technique using a monoclonal antibody against serotonin immunoreactive sites, with argyrophil staining using the Grimelius technique, and with argentaffin staining using the Masson-Fontana technique. A good correlation between all three techniques in the diagnosis of ileal carcinoid tumour was found, but the immunoperoxidase technique showed greater sensitivity than the Masson-Fontana technique and greater specificity than the Grimelius technique in the diagnosis of foregut and hindgut carcinoid tumours. The immunoperoxidase technique with a monoclonal antibody against serotonin immunoreactive sites (YC5/45) is recommended as a sensitive and specific test for carcinoid tumours. The reactions in other endocrine tumours are also included.