Pollen tube attraction by the synergid cell.

In flowering plants, guidance of the pollen tube to the embryo sac (the haploid female gametophyte) is critical for successful fertilization. The target embryo sac may attract the pollen tube as the final step of guidance in the pistil. We show by laser cell ablation that two synergid cells adjacent to the egg cell attract the pollen tube. A single synergid cell was sufficient to generate an attraction signal, and two cells enhanced it. After fertilization, the embryo sac no longer attracts the pollen tube, despite the persistence of one synergid cell. This cessation of attraction might be involved in blocking polyspermy.

The evaluation of whitening efficacy of cosmetic products using a human skin pigmentation spot model.

BACKGROUND: To establish a pigmentation spot model on human skin and to assess whitening efficacy for whitening products by this established pigmentation spot model. METHODS: Twenty subjects between 20 and 45 years old with skin phototype III or IV were selected. Three consecutive daily UV exposures were performed on buttocks of the subjects as follows: Day 1=1 minimal erythema dose (MED), Day 2=0.5 MED and Day 3=0.5 MED. After the first UV exposure, a selected whitening product was applied to the subjects twice a day on UV exposure area. The application of the whitening product to subjects on the exposed areas was continued till Day 27. CM2500d chromameter, Maxmeter MX18 and visual evaluation were used to assess changes of skin color. RESULTS: A pigmentation spot model after UV exposure was established. The measurement of the pigment spot showed that L* value declined abruptly at Day 3 and then slowly reached to a lowest point at Day 6. L* value of the pigment spot almost remained at the same level until Day 20, thereafter increased slowly. The a* value showed an abrupt increase at Day 3 and slowly reached to a maximal level at Day 6. The a* value slowly declined toward its baseline level. Likewise, the erythema index also increased significantly at Day 3, and reached to a maximal level at Day 6 and then slowly declined. However, L*, a* and erythema indices did not return to their baseline levels during the 27-day period of this study. On the other hand, b* value started to increase from Day 3 and such increase was observed continuously to Day 27. Melanin index also showed a slow increase during the first 3 days. It started to increase rapidly from Day 3 and a to maximal level at Day 9 and maintain at a plateau till Day 27 (with an exception at Day 13). To assess the whitening product by this pigmentation spot model, DeltaL, Deltab*, and DeltaM values were analyzed. It showed that absolute DeltaL value and Deltab*value of whitening products were lower than those values of the vehicle of the whitening product at each checkpoint, while DeltaM value of the whitening product was lower only at Day 9 and Day 20, although no statistically significant differences was found. The visual results also strongly supported that the whitening product enhanced the decrease of pigmentation. CONCLUSION: This study showed that repeated UV exposure was able to induce a long extensive period of pigment formation. The resulted pigmentation spot was able to maintain at an elevated level till Day 20. Clinical subjective evaluations together with combined objective instrument measurements were still important to assess whitening and spot-removing ability of a material due to the instrument limitation for color differentiations. This kind of pigmentation spot model can be used to assess whitening efficacy for whitening or spot-removing products. In addition, the combinations of subjective and objective methods were able to serve as advisable references to assess the whitening efficacy of products.

Ventricular defibrillation using biphasic waveforms: the importance of phasic duration.

Biphasic waveforms can be used to defibrillate the heart with less energy than that used by monophasic waveforms. In 14 anesthetized open chest dogs with large contoured defibrillation electrodes, the effect on defibrillation efficacy of varying the duration of the two phases of biphasic waveforms was studied. All combinations of 0, 1, 3.5, 6 and 8.5 ms duration were used for both the first and the second phase except for the meaningless case in which both durations were 0 ms. The 3.5-2 waveform (3.5 ms first phase and 2 ms second phase) was also tested. All the hearts were defibrillated with less than or equal to 5 joules using any of the 25 waveforms. However, biphasic waveforms with the second phase shorter than or equal to the first had significantly lower defibrillation thresholds than did those with the second phase longer than the first or than did monophasic waveforms of approximately the same total duration. A plot of defibrillation threshold current strength versus second phase duration for all biphasic waveforms with a 3.5 ms first phase did not produce a hyperbolic strength-duration curve as seen with monophasic waveforms. To verify these findings, defibrillation dose-response curves were obtained for the 3.5-2, 6-6 and 3.5-8.5 biphasic waveforms in another six dogs. The 50 and 80% successful voltage doses of the 3.5-8.5 waveforms were significantly higher than those of the other two waveforms, which were not different from one another.(ABSTRACT TRUNCATED AT 250 WORDS)

Presence of anti-pituitary antibodies and GAD antibodies in NIDDM and IDDM.

OBJECTIVE: To evaluate the clinical significance of the presence of anti-pituitary antibodies (APAs) in patients with NIDDM or IDDM and to examine the relationship of APAs to GAD antibodies (GADAs). RESEARCH DESIGN AND METHODS: Serum samples were obtained from patients with NIDDM and IDDM. APAs, determined by Western blot analysis, and GADAs, determined by radioimmunoassay, were detected in the patients' sera and control sera. Urinary levels of C-peptide (U-CPR) were measured. RESULTS: The prevalence of APAs was significantly higher in patients with NIDDM (24.2%) or IDDM (56.8%) than in healthy control subjects (6%). In patients with NIDDM, the levels of U-CPR were significantly lower, and the prevalence of insulin deficiency was higher in APA+ patients than in APA- patients. CONCLUSIONS: This is the first study to demonstrate that the prevalence of APAs is increased in patients with NIDDM and IDDM. The presence of APAs may be related to reduced secretion of insulin in NIDDM patients.

Hepatic artery thrombosis in living related liver transplantation.

BACKGROUND: Hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss in pediatric patients. We previously reported that the microsurgical techniques for arterial anastomosis can reduce the incidence of HAT in living related liver transplantation (LRLT). The purpose of this study is to analyze the risk factors for HAT after LRLT. A total of 245 patients received 250 liver transplants. METHODS: Eight arteries in eight patients, reconstructed with the use of loupe magnification (HAT; 1/8, 12.5%), were excluded from this study. We observed HAT in 4 patients of the 242 transplants (1.7%, HAT group). Seventeen factors were compared between the HAT and the control group (those without HAT). RESULTS: HAT occurred in 3 of 33 grafts (9%) from ABO-incompatible donors, whereas it occurred in 1 of 209 grafts (0.5%) from identical or compatible donors (P=0.008). The corrected volume of fresh-frozen plasma intraoperatively transfused in the HAT group (46.9+/-30.3 ml/kg) was significantly (P=0.015) different from that in the control group (10.2+/-1.9 ml/mg). In all four patients with HAT, emergent revisions of the anastomosis were performed. Two patients with ABO-incompatible grafts died of hepatic failure and sepsis. CONCLUSIONS: Although microsurgical techniques can minimize the surgical risk factors for HAT, overtransfusion of fresh-frozen plasma in high-risk patients (ABO incompatible) may be a critical factor in the development of HAT in LRLT.

Auxiliary partial orthotopic liver transplantation from living donors: significance of portal blood flow.

BACKGROUND: Auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. However, functional competition has been reported even in auxiliary partial orthotopic liver transplantation (APOLT). We evaluated herein the interaction in APOLT between the native liver and the graft in terms of portal blood flow and regeneration. The need for diversion of the portal blood flow to the graft was also assessed. METHODS: A total of 15 patients received APOLT from living donors. Portal blood flow to the native liver was preserved in 6 patients, and the portal vein to the native liver was preemptively transected at the time of transplantation in 9 patients. RESULTS: Of the patients with preservation of the portal blood flow to the native liver, two showed inadequate graft portal blood flow just after operation, and in the other three patients the graft portal blood flow decreased or the graft atrophied after deterioration of the graft function. In the patients with preemptive transection of the portal vein to the native liver, optimal graft portal blood flow was obtained, and the native liver, supplied only by arterial inflow, supported a small-for-size graft until the graft regenerated. The damage to the native liver was minimal. CONCLUSIONS: Functional competition may occur in APOLT with preservation of the portal blood flow to the native liver, whereas preemptive transection of the native liver portal vein is a safe procedure and effectively prevents the portal steal phenomenon.

Coexistence of a graft with the preserved native liver in auxiliary partial orthotopic liver transplantation from a living donor for ornithine transcarbamylase deficiency.

BACKGROUND: Auxiliary partial orthotopic liver transplantation (APOLT) has recently been performed in patients with noncirrhotic metabolic liver diseases. However, long-term outcomes for the preserved native liver and the transplanted liver graft have not been clearly established yet. METHODS: The recipient was a 36-month-old girl with ornithine transcarbamylase deficiency. She underwent APOLT, using her father's left lateral segment. RESULTS: Liver function was normalized soon after APOLT and the patient was able to ingest a normal diet without medication. Coexistence of the well-functioning native liver and graft was demonstrated in a computed tomography scan, Doppler ultrasonography, scintigraphy, and histological examination, during a relatively long-term follow-up period. CONCLUSIONS: APOLT seems to be most useful for the treatment of noncirrhotic metabolic liver diseases.

Comparison of gastric mucosal surface pH response times after intravenous administration of histamine2-receptor antagonists.

Gastric mucosal surface pH was measured endoscopically in patients with peptic ulcer, erosive gastritis, or nonulcer dyspepsia following intravenous administration of either 200-mg cimetidine, 50-mg ranitidine, or 40-mg famotidine. The mean baseline pH in the three treatment groups before drug administration ranged from 0.85 to 0.99, with no significant difference between groups. Following treatment with cimetidine, ranitidine, and famotidine, the mean response times for the mucosal surface pH values to increase to 3.5 were 10.1 +/- 5.9 minutes, 11.2 +/- 6.8 minutes, and 17.3 +/- 6.7 minutes, respectively. The corresponding response times to reach pH levels of 6.0 were 16.0 +/- 9.4 minutes, 17.0 +/- 5.4 minutes, and 31.2 +/- 21.7 minutes, respectively. The response times to pH levels of 3.5 and 6.0 were significantly faster in patients who received cimetidine compared with patients who received famotidine (P = 0.0088 to pH 3.5 and P = 0.046 to pH 6.0). The differences between cimetidine and ranitidine were not significant. These findings suggest that at recommended clinical doses, intravenous cimetidine provides rapid elevation of the gastric mucosal surface pH compared with other histamine2-receptor antagonists. This finding may be particularly relevant in the emergency care of patients with severe peptic ulcer disease (eg, patients with gastrointestinal hemorrhage).

Transient giant negative T wave in acute anterior myocardial infarction predicts R wave recovery and preservation of left ventricular function.

OBJECTIVE: To investigate the value of a giant negative T wave (> or = 1.0 mV) in precordial leads of 12-lead electrocardiograms in the acute phase of Q wave myocardial infarction as a predictor of myocardial salvage. METHODS: Coronary angiographic and electrocardiographic findings, left ventricular ejection fraction in the chronic stage, and levels of cardiac enzymes were compared in patients with myocardial infarction with (group GNT, n = 31) and without (group N, n = 20) a giant negative T wave. GNT patients were divided into two subgroups according to the presence (GNT:R[+], n = 10) or absence (GNT: R[-], n = 21) of R wave recovery with an amplitude > or = 0.1 mV in at least one lead that had shown Q waves. RESULTS: The maximum level of creatine kinase and the total creatine kinase were lower in group GNT compared with group N (P < 0.05). The left ventricular ejection fraction was higher in group GNT than in group N (P < 0.05). The maximum creatine kinase and total creatine kinase were lower in GNT:R(+) than in GNT:R(-) (P < 0.01). The left ventricular ejection fraction was higher in GNT:R(+) than in GNT:R(-) (P < 0.01). The frequency of R wave recovery was significantly higher when giant negative T waves appeared within 100 h of myocardial infarction or when the maximum potential was > or = 1.4 mV. The appearance of a giant negative T wave > or = 1.4 mV had a sensitivity of 90%, a specificity of 71.4%, a diagnostic accuracy of 77.4%, a positive predictive value of 60%, and a negative predictive value of 93.8% for prediction of R wave recovery. CONCLUSIONS: The appearance of a giant negative T wave, especially within 100 h of the onset of myocardial infarction, with a maximum potential of > or = 1.4 mV, may predict a reappearance of the R wave and a better left ventricular function in patients in the chronic stage of anterior myocardial infarction.

Effect of cadmium on Japanese encephalitis virus infection in mice. 1. Acute and single-dose exposure experiment.

When mice were treated with 0.09 mg cadmium chloride (Cd) per mouse once and inoculated i.p. simultaneously with Japanese encephalitis virus (JEV) they showed a significant difference in the incubation time and mortality between the treated and untreated groups in repeated experiments. Cd treatment shortened the incubation time and the mortality increased greater than twice compared with the untreated control. This effect was not observed in the case of intracerebral inoculation of JEV. Effects of Cd on antibody formation in mice were also determined. Animals given a single s.c. dose of Cd were immunized with JE inactivated vaccine once simultaneously. When mice were treated with Cd, they did not show low neutralizing and hemagglutination inhibition activities compared with the control mice. Pretreatment of Cd did not affect any mortality or antibody formation.

Laboratory diagnosis of dengue virus infection by reverse transcriptase polymerase chain reaction (RT-PCR) and IgM-capture enzyme-linked immunosorbent assay (ELISA).

Dengue virus infections are a major public health problem in most tropical and sub-tropical countries of the world. Dengue is occasionally imported by travelers who visit tropical areas and become infected with dengue virus. Laboratory diagnosis is essential for confirming the diagnosis of this virus. For purposes of confirmation, detection of specific IgM by IgM-capture enzyme-linked immunosorbent assay (ELISA) and of dengue virus genome by reverse transcriptase polymerase chain reaction (RT-PCR) have recently been used. In the present study, we tested serum specimens from dengue-suspected Japanese cases, by IgM-capture ELISA, RT-PCR, HI, and virus isolation. Serum samples collected before or on the day of defervescence were positive by RT-PCR, though no PCR-positive samples were obtained after fever day 1. IgM-capture ELISA was positive as early as disease day 4, and all samples but one were IgM-positive when collected on disease day 5 or later. In light of these findings, we recommend that both RT-PCR and IgM-capture ELISA be performed, irrespective of the stage of dengue illness. Combination of RT-PCR and IgM-capture ELISA increases the ability to diagnose dengue virus infection, even in the only that a single serum specimen from the patient is available.

Evaluation of an automatic cardiac activation detector for bipolar electrograms.

The identification of local activation events in bipolar cardiac electrograms, the first step of isochronal map construction, is a time-consuming and difficult process. Owing to the variability among bipolar activation complexes and the lack of practical knowledge concerning the relationship of the bipolar waveform to action potential characteristics, a set of empirical rules to guide the assignment of local activation times have been adopted. A computer program, called AP, has been designed, which implements these rules in the form of a syntactic analyser. Canine epicardial recordings were used to evaluate AP by comparing local activation times, assigned by AP, with times assigned independently by three investigators. The Hermes-Cox model for detector evaluation and a bootstrap statistical method were used in conjunction with ROC analysis to evaluate the ability of AP to detect events. Analysis of discrepancies among investigator-assigned times showed that the reliabilities of AP event detection and AP-assigned times were comparable to those of the investigators. The methods used in system design and evaluation are applicable to a broad range of problems in the detection and localisation of waveform components.

[Current status of Japanese encephalitis in Japan].

Japanese encephalitis (JE) cases confirmed by serological and/or virological tests, and clinically typical fatal JE cases have been collected using individual report cards in Japan since 1965. A total of 324 confirmed cases (male: 167, female: 157) reported between 1982 and 1996 were analyzed. Annual incidence of JE cases was less than one hundred cases from 1982 to 1991, and less than 10 cases after 1992. Age distribution of the patients was: 0-9 years old, 43 cases (13%); 10-39 years old, 30 cases (9%); 40-69 years old, 161 cases (50%); over 70 years old, 90 cases (29%). The highest incidence in male cases was observed in the age group of 50-59 years, and that in female was in 60-69 years. Most of the patients (95%) were living in the western parts of Japan. No patient was reported from Okinawa, southern-most prefecture of Japan, and from Tohoku-Hokkaido area, northern parts of Japan. The date of onset were distributed from the end of July to the end of October, and the highest incidence was observed in the end of August. Prognosis of the patients were: complete recovery, 99 cases (31%); sequelae, 156 cases (48%); total, 56 cases (17%); unknown, 13 cases (4%). Vaccination histories of patients were reported as vaccinee, 4 cases (1%); incomplete vaccinee, 14 cases (4%); non-vaccinee, 181 cases (56%); unknown, 125 cases (39%). Spread of JE virus in Japan has not been diminished as shown by the data of antibody acquisition of young swine in every summer in Japan. Based on these observations we conclude that JE vaccination has contributed to maintaining the low JE incidence among children in Japan.

[Laboratory virological diagnosis of imported dengue cases].

Suspected dengue cases in Japan during the period of 1985-1995, 173 cases with unknown febrile illness entering or returning from mostly southeast Asia, were tested by serology and RT-PCR gene amplification. Seventy seven cases were confirmed by a significant rise of dengue 2 (Den 2) HI antibody in paired sera or by detection of HI antibody titer higher than 1:320 in single serum. The other 3 cases with antibody levels not higher than 1:80 in paired sera and 12 cases with an antibody 1:160 in single sera were positively suspected of dengue infection but were not confirmed. Countries of origin of confirmed cases were Thailand (39 cases), Philippinse (15), India (13), and Indonesia (9). Sera of dengue cases showed high degrees of cross reactivity of Japanese encephalitis virus (JEV) in HI test but not in IgM capture ELISA. Sera of confirmed JEV-infected cases, however, showed practically no cross reactivity to Den 1 4 in HI test, suggesting unilateral cross reactivity of HI antibody. RT-PCR detected the Den 1 genome in sera of 3 cases obtained within 3 days after onset and the Den 2 genome in serum of case 4 days after onset. Although the number is limited, 92 (53%) out of 173 cases of febrile illness of unknown etiology entering Japan from tropical countries were either confirmed or positively suspected to be dengue fever. Considering possibilities of under reporting, importations of tropical viral infections should be bigger in number and will necessitate our intensified alertness.

[Study on consonant confusion in Japanese patients with sensorineural hearing loss].

The speech discrimination scores of a 57S word list were analyzed in 180 patients with sensorineural hearing loss. Confusion matrices were made on consonant groups of voiceless, voiced and nasal consonants. In succession, the incidence of consonants was compared between the 57S word list and Japanese conversation. Consonants with high incidence in Japanese conversation were t, h, d, g, m, and n. Patients with sensorineural hearing loss are apt to confuse t and h to k, d to b or r, g to b, d or r, m to n or r, and n to m or r. It is effective to correct these instances of consonant confusion, for improving conversational ability in Japanese patients with sensorineural hearing loss.

[Detection methods of anti-pituitary autoantibodies].

Bottazzo et al. first reported an assay method of antibodies to human pituitary endocrine cells, using an indirect immunofluorescent technique in 1975. In 1986 Sugiura et al. established a sensitive assay method for pituitary cell antibodies by biotin/avidin detection technique using rat pituitary. They also developed a sensitive assay for antibodies to anterior pituitary cell membrane by immunofluorescence methods using AtT-20 cells and GH3 cells. Recently Crock et al. reported a new approach to the detection of pituitary antibodies by immunoblotting. We focused on assay methods reported previously, including our results of pituitary antibodies in patients with autoimmune thyroid disease. The existence of autoimmune disorders of the pituitary is now accepted on both experimental and clinical grounds.

[B/F non-separative method].

In homogeneous enzyme immunoassay without requirement of separation of free and bound label, the concentration of substances in samples can be detected by measurement of enzyme activity in the mixtures of samples (antigen) and reagents (labeled antigens antibodies, and enzyme substrates). The methods described herein offer the virtues of simplicity and rapidity by use of general-purpose automated clinical analyzer. The concentrations of some drugs, hormones, antibiotics, and very small amount of certain proteins are now detected by the routine examination in these techniques employing commercial diagnostic kits offered by several companies. In this manuscript, we attempted to give an overview of the principle of various methods by use of commercial diagnostic kit applied in routine clinical examinations.