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Biomedical subjects

N Masuda

Publications and source records attributed to N Masuda.

At least 127 records · Page 7Linked to original sources
PubMed1995

[Molecular genetics of Huntington's disease].

Huntington's disease (HD) is a progressive neurodegenerative disorder which is clinically characterized by chorea, cognitive decline, and emotional disturbance; it is inherited in an autosomal dominant manner. The HD gene maps to chromosome 4p16.3. Our linkage analysis demonstrated a significant genetic linkage between Japanese HD families and the flanking markers, D4S127, D4S43. The molecular basis of the disease is an expansion of CAG repeat in the huntingtin gene. We performed molecular analysis of the repeat in Japanese HD patients and normal controls. The size of the CAG repeat ranged from 37 to 95 repeats in affected subjects and from seven to 29 in normal controls. A significant correlation was found between the age of onset and the CAG expansion. The length of the expanded repeat is unstable in meiotic transmission and large increases occur in paternal transmission. At the same time the CCG repeat polymorphism adjacent to the CAG repeat was analysed and haplotypes of HD chromosomes were identified. Striking linkage disequilibrium was found between the CAG repeat expansion and an allele of (CCG)10 in Japanese HD chromosome. It is distinct from that described previously in western populations. Western HD chromosomes strongly associate with an allele of (CCG)7.

Age of Onset↗
PubMed1994

Cardiovascular effects of YM099, a novel K+ channel opener, in anesthetized and conscious dogs.

Cardiovascular effects of a newly synthesized benzoxadiazol derivative K+ channel opener, YM099, 2-(7,8-dihydro-6,6-dimethyl-6H-[1,4]oxazino[2,3- f][2,1,3]benzoxadiazol-8-yl) pyridine N-oxide, were evaluated in dogs. In pentobarbital-anesthetized dogs, YM099 (1-10 micrograms/kg i.v.), similarly to levcromakalim (1-10 micrograms/kg i.v.), dose dependently increased coronary artery blood flow, max.d p/dt and cardiac output, and decreased total peripheral resistance and mean blood pressure, with a small increase in heart rate. These vasodilator effects were antagonized by glibenclamide (3 mg/kg i.v.). Interestingly, YM099 selectively increased coronary artery blood flow, although it increased carotid, coronary, mesenteric and renal artery blood flows and cardiac output. In addition, YM099 (1-10 micrograms/kg i.v.) increased large conductive coronary artery vessel diameter as well as coronary artery blood flow. In conscious dogs, YM099 (100 micrograms/kg i.v.) also increased the diameter of large conductive and small resistive coronary arteries. In conclusion, YM099 is a potent vasodilator agent, with particularly pronounced effects on the coronary artery. These effects of YM099 may be mediated by the opening of ATP-sensitive K+ channels.

Adenosine Triphosphate↗
PubMed1994

Polyamine-sensitive magnesium transport in Saccharomyces cerevisiae.

In Saccharomyces cerevisiae we found a toxic effect of polyamines, well-known metabolites important for cell proliferation; in magnesium-limited (50 microM Mg2+) synthetic medium, cell growth was severely inhibited by spermine, spermidine and putrescine in descending order. In conjunction with a decrease in the growth rate by the addition of 0.5 mM spermine, the internal Mg2+ content decreased and the spermine content increased. When cell growth ceased, the Mg2+ content had finally decreased to about 40% of the value before the addition of spermine (120-130 nmol/mg dry weight), and the spermine content concomitantly increased 30-fold (from 1 to 30 nmol/mg dry weight); spermine4+ apparently took the internal place of Mg2+ with a probable stoichiometry of 1:2. However, the total amount of Mg2+ retained in the cells remained constant even with the addition of spermine, suggesting that spermine blocks Mg2+ accumulation. In high (2 mM) Mg2+ medium, cell growth was hardly affected by polyamines, and an exchange of spermine and Mg2+ was minimal. Energy-dependent Mg2+ uptake by whole cells was inhibited by spermine, spermidine and putrescine in a similar manner as the growth rates. On the other hand, Mg2+ inhibited spermine uptake. These results suggest that competition takes place between extracellular spermine and Mg2+ for their accumulations. It is thus clear that polyamine-sensitive Mg2+ transport system is indispensable for the physiology of this organism.

Biological Transport↗
PubMed1994

Photodynamic therapy and/or external beam radiation therapy for roentgenologically occult lung cancer.

BACKGROUND AND METHODS: Thirty-nine roentgenologically occult lung cancers in 29 patients were treated using photodynamic therapy (PDT) and/or thoracic radiotherapy (TRT) from January 1986 to March 1992. With the exception of one mixed-tumor case, all were squamous cell carcinomas. RESULTS: Initial PDT achieved complete responses in 25 of 39 (64%) of the cancers. Of the remaining 14 cancers that showed less than complete response (CR), 10 of the 14 (71.4%) showed a CR when subsequently treated with TRT, yielding an overall CR rate of 89.7% for cancers treated. Although nine patients experienced recurrences, six of these had CR when treated with PDT and/or TRT. To date, 22 patients are alive. Causes of death in the patients enrolled in this study are as follows: pyothorax (2); heart failure due to pulmonary hypertension (1); chronic respiratory insufficiency (1); subsequent primary brain cancer (1); and subsequent primary lung cancer (1). Only one died of primary lung cancer. CONCLUSIONS: These findings suggest that PDT and/or TRT may be used as an alternative to surgery in the treatment of selected patients with roentgenologically occult lung cancer.

Adult↗
PubMed1994

The role of extracellular Ca2+ in carbachol-induced tonic contraction of the pig detrusor smooth muscle.

The role of extracellular Ca2+ in the tonic-contractile response to muscarinic receptor stimulation was investigated in isolated detrusor smooth muscle from the pig urinary bladder. Carbachol (10(-8)-10(-5) M) produced a concentration-dependent contractile response in isolated pig detrusor smooth muscle strips consisting of an initial phasic component followed by a tonic component. During the plateau of the tonic contractions induced by carbachol at the submaximal concentration of 10(-6) M, the inhibiting effects of atropine, EGTA, nifedipine (a voltage-dependent calcium channel antagonist), H-7 [a protein kinase C (PKC) inhibitor] and YM934 (a potassium channel opener) on the contractions were evaluated. Atropine (10(-10)-3 x 10(-8) M) concentration-dependently inhibited the tonic contractions induced by carbachol. In the same experimental conditions, EGTA (4 mM) and nifedipine (10(-9)-3 x 10(-7) M) depressed the tonic contractions in a concentration-dependent manner as did H-7 (10(-5)-3 x 10(-5) M) and YM934 (10(-8)-10(-6) M). However, H-7 (10(-5)-3 x 10(-5) M) and YM934 (10(-6) M) were very weak in inhibiting the contractions induced by KCl (50 mM) in isolated pig detrusor smooth muscle strips. These results suggest that the tonic-contractile response induced by carbachol in pig detrusor smooth muscle strips is dependent mainly on depolarization of the cell membranes and an influx of extracellular Ca2+, and also suggest that this depolarizing response may be due to inactivation of ATP-sensitive potassium channels through muscarinic activation of PKC.

Animals↗
PubMed1994

Clinical studies of irinotecan alone and in combination with cisplatin.

Irinotecan (CPT-11), a new derivative of camptothecin, showed schedule-dependent antitumor activity and toxicity in preclinical animal studies. We carried out a phase I study of weekly CPT-11 infusion, which indicated that the recommended dose for phase II studies was 100 mg/m2. In a phase II trial, CPT-11 achieved a response rate of 32% for non-small cell lung cancer (NSCLC). In two phase II trials, CPT-11 achieved objective response rates of 37% and 47% for small cell lung cancer (SCLC). The high activity of CPT-11 in these phase II studies suggested that the next rational step was to investigate combination chemotherapy. The first phase I trial of CPT-11 combined with cisplatin achieved an encouraging response rate of 54% in 27 patients with previously untreated NSCLC, and the recommended schedule for phase II studies was 60 mg/m2 of CPT-11 (days 1, 8, and 15) plus 80 mg/m2 of cisplatin (day 1) given at 4-week intervals. Given the high single-agent activity of CPT-11 against SCLC and NSCLC, a regimen with a higher dose of this agent and a lower dose of cisplatin seemed likely to be more effective. In the second trial, the cisplatin dose was accordingly reduced from 80 to 60 mg/m2, and the recommended dose of CPT-11 was concluded to be 80 mg/m2. Thus, reduction of the cisplatin dose to 60 mg/m2 allowed the safe administration of CPT-11 at 80 mg/m2 (33.3% dose intensification compared with the original regimen). The most recent trial of this combination with recombinant human granulocyte colony-stimulating factor (rhG-CSF) support demonstrated that the recommended dose is 80 mg/m2 of CPT-11 and 80 mg/m2 of cisplatin. Thus, we could raise the CPT-11 dose 33% above that given in the original regimen while maintaining the original cisplatin dose by the use of rhG-CSF support. Further trials are needed to evaluate the effect of CPT-11 given in combination with other active agents for the treatment of lung cancer.

Adult↗
PubMed1994

Degradation of alkylphenol ethoxylates by Pseudomonas sp. strain TR01.

An alkylphenol ethoxylate-degrading bacterium was isolated from activated sludge of a municipal sewage treatment plant by enrichment culture. This organism was found to belong to the genus Pseudomonas; since no corresponding species was identified, we designated it as Pseudomonas sp. strain TR01. This strain had an optimal temperature and pH of 30 degrees C and 7, respectively, for both growth and the degradation of Triton N-101 (a nonylphenol ethoxylate in which the average number of ethylene oxide [EO] units is 9.5). The strain was unable to mineralize Triton N-101 but was able to degrade its EO chain exclusively. The resulting dominant intermediate was identified by normal-phase high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry as a nonylphenol ethoxylate with 2 mol of EO units. A carboxylated metabolite, [(nonylphenoxy)ethoxy]acetic acid, was detected by gas chromatography-mass spectrometry. This bacterium also metabolized alcohol ethoxylates with various numbers of EO units but not polyethylene glycols whatever their degree of polymerization. By oxygen consumption assay, the alkyl group or arene corresponding to the hydrophobic part of alcohol ethoxylates or alkylphenol ethoxylates was shown to contribute to the induction of the metabolic system of the EO chain of Triton N-101, instead of the EO chain itself, which corresponds to its hydrophilic part. Thus, the isolated pseudomonad bacterium has unique substrate assimilability: it metabolizes the EO chain only when the chain linked to bulky hydrophobic groups.

Biodegradation, Environmental↗
PubMed1994

Phase I study of irinotecan and cisplatin with granulocyte colony-stimulating factor support for advanced non-small-cell lung cancer.

PURPOSE: Since leukopenia was one of the dose-limiting toxicities of the combination of irinotecan (CPT-11) and cisplatin in a previous trial, we conducted a phase I trial to investigate whether support with recombinant human granulocyte colony-stimulating factor (rhG-CSF) would permit further intensification of the CPT-11 dose in combination with a fixed cisplatin dose. PATIENTS AND METHODS: Twenty previously untreated patients with stage IIIB or IV non-small-cell lung cancer (NSCLC) were treated with CPT-11 on days 1, 8, and 15 in combination with cisplatin 80 mg/m2 intravenously on day 1. In addition, rhG-CSF (2 micrograms/kg/d) was administered on days 4 to 21, except on the days of CPT-11 treatment. The starting dose of CPT-11 was 70 mg/m2, and the CPT-11 dose was escalated in 10-mg/m2 increments until the maximum-tolerated dose was reached. RESULTS: Diarrhea was the dose-limiting toxicity at 90 mg/m2. Two of six patients experienced either grade 3 or 4 diarrhea or grade 3 leukopenia during the first course of therapy at this dose level. Modest escalation of the CPT-11 dose from 80 to 90 mg/m2 resulted in a marked increase in the plasma concentration of 7-ethyl-10-hydroxycamptothecin (SN-38). Occurrence of diarrhea was well correlated with the peak plasma concentration (Cmax) of SN-38 (P = .035). There were 10 partial responses (50%) among 20 patients. CONCLUSION: The recommended dose for phase II studies is 80 mg/m2 of CPT-11, and 80 mg/m2 of cisplatin plus rhG-CSF. With the use of rhG-CSF, the CPT-11 dose can be increased 33% above that in the original regimen (60 mg/m2 of CPT-11 and 80 mg/m2 of cisplatin).

Adult↗
PubMed1994

Role of radiotherapy in combined modality treatment of locally advanced non-small-cell lung cancer.

PURPOSE: For patients with locally advanced (stage III) non-small-cell lung cancer (NSCLC), radiotherapy (RT) has been used conventionally for many years. Few prospective trials have determined the role of RT. Recently, chemotherapy (CT) has been shown to produce excellent responses in regionally advanced disease. We therefore conducted a randomized trial using cisplatin (P)-based CT regimens with or without thoracic irradiation. PATIENTS AND METHODS: We randomly assigned 92 patients with locally advanced NSCLC to receive one of three arms of P-based combination chemotherapy: vindesine (V) plus P, mitomycin (M) plus V plus P, or etoposide (E) plus P alternating with V plus M. After two cycles of CT, patients were reevaluated and those with stage III were again randomized to receive RT or not. RT consisted of 50 to 60 Gy in 5 to 6 weeks; 2 Gy was delivered once daily in conventional fractions. RESULTS: Sixty-three patients were included in the second randomization. The patients in the CT/RT group (n = 32) and CT-alone group (n = 31) were comparable in terms of age, sex, performance status, histologic features, stage of disease, and induction CT regimen. The median durations of survival were similar for the two groups (461 days in CT/RT group and 447 days in CT-alone group). The survival rate in the CT/RT group was 58% at 1 year, 36% at 2 years, and 29% at 3 years, as compared with 66%, 9%, and 3% at 1, 2, and 3 years, respectively, in the CT-alone group. One patient in the CT/RT group died of pneumonitis, but there were no CT-related deaths. CONCLUSION: In locally advanced NSCLC, P-based combination CT followed by chest irradiation significantly increases the number of long-term survivors as compared with CT alone. RT to bulky disease in the thorax is thus an important part of combined modality therapy, and a necessary part of further studies in locally advanced disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Phase I and pharmacologic study of irinotecan and etoposide with recombinant human granulocyte colony-stimulating factor support for advanced lung cancer.

PURPOSE: We conducted a phase I trial of irinotecan (CPT-11), a topoisomerase I inhibitor, combined with etoposide, a topoisomerase II inhibitor, and recombinant human granulocyte colony-stimulating factor (rhG-CSF) support because of the overlapping neutrophil toxicity of both drugs. The aim was to determine the maximum-tolerated dose of CPT-11 combined with a fixed dose of etoposide in patients with advanced lung cancer, as well as the dose-limiting toxicities of this combination. PATIENTS AND METHODS: Twenty-five patients with stage III or IV lung cancer, 15 (60%) with prior chemotherapy, were treated at 4-week intervals using CPT-11 (90-minute intravenous infusion on days 1, 8, and 15) plus etoposide (80 mg/m2 intravenously on days 1 to 3). In addition, rhG-CSF (2 micrograms/kg/d) was given from day 4 to day 21, except on the days of CPT-11 administration. The starting dose of CPT-11 was 60 mg/m2, and it was escalated in 10-mg/m2 increments until the maximum-tolerated dose was reached. RESULTS: The maximum-tolerated dose of CPT-11 was 90 mg/m2, since two of the three patients developed grade 3 to 4 leukopenia or grade 3 to 4 diarrhea during the first cycle of treatment at this dose level. Diarrhea and leukopenia were the dose-limiting toxicities, while thrombocytopenia was only a moderate problem. Elimination of CPT-11 was biphasic, with a mean +/- SD beta half-life of 18.17 +/- 9.09 hours. The mean terminal half-life of 7-ethyl-10-hydroxycamptothecin (SN-38; the major metabolite of CPT-11) was 43.40 +/- 37.84 hours. There was one complete response (5%) and eight partial responses (38%) among 21 assessable patients, for an overall response rate of 43%. The response rates for small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC) were 58% (seven of 12 patients) and 22% (two of nine patients), respectively. CONCLUSION: The combination of CPT-11 and etoposide with rhG-CSF support seems to be active against lung cancer, especially SCLC, with acceptable toxicity. The recommended dose for phase II studies in previously untreated patients is 80 mg/m2 of CPT-11 (days 1, 8, and 15) and 80 mg/m2 of etoposide (days 1 to 3) plus 2 micrograms/kg of rhG-CSF (days 4 to 21, except when CPT-11 is given). In addition, 70 mg/m2 of CPT-11 appears to be the appropriate dose for previously treated patients receiving this regimen.

Adult↗
PubMed1994

Pharmacologic profiles of YM934, a novel potassium channel opener.

Pharmacologic profiles of YM934, a newly synthesized 1,4-benzoxazin derivative K channel opener were evaluated in in vitro and in vivo experiments. In isolated rat portal vein, YM934 and a benzopyran derivative K channel opener lemakalim inhibited the frequency of spontaneous rhythmic contractions concentration dependently, with IC50 values of 14 and 38 nM, respectively. These inhibitory effects were competitively antagonized by glibenclamide (an ATP-sensitive K channel blocker; 10(-7)-3 x 10(-6) M). In isolated rabbit aorta, YM934 (10(-8)-10(-6) M) and lemakalim (10(-8)-10(-6) M) relaxed the contractions induced by 20 mM KCl concentration dependently but were ineffective against the contractions induced by 50 mM KCl. YM934 (10(-8)-3 x 10(-6) M) and lemakalim (3 x 10(-8)-10(-5) M), but not the calcium antagonist nifedipine, relaxed the contractions induced by norepinephrine (NE 10(-6) M) or prostaglandin F2 alpha (PGF2 alpha 3 x 10(-6) M) in the aorta. In pentobarbital-anesthetized dogs, YM934 (1-10 micrograms/kg intravenously, i.v.) dose-dependently increased coronary artery blood flow (CBF), and decreased total peripheral resistance (TPR) and mean blood pressure (MBP). YM934 selectively increased CBF, but had little effect on vertebral, carotid, mesenteric, renal and femoral artery BF. These vasodilatory effects of YM934 were antagonized by glibenclamide. YM934 is a potent K channel opener and possesses potent vasodilatory effects, with particularly pronounced effects on the coronary artery. These effects of YM934 may, like lemakalim, be mediated by opening of ATP-sensitive K channels.

Anesthesia↗
PubMed1993

Carcinomatous neuropathy associated with hepatic cell carcinoma: an autopsy case report.

A 76-yr-old male patient with carcinomatous neuropathy associated with hepatic cell carcinoma, whose initial symptom was deep sensory disturbance followed by muscle weakness is described. The onset was subacute, followed by slow progression. Sural nerve biopsy, as well as electrophysiological examinations, revealed severe axonal degeneration without any evidence of demyelination. The autopsy findings were similar to findings described in the literature on carcinomatous neuropathy. Although carcinomatous neuropathy is usually associated with lung cancer, this report describes an association with hepatic cell carcinoma. The patient also had motor nerve involvement with positive serum anti-GM1 ganglioside antibody which decreased after immunosuppressant therapy in parallel with recovery of muscle weakness. The anti-GM1 ganglioside antibody may be involved in the pathogenesis of motor disturbance in the present case.

Aged↗
PubMed1993

Phase I and pharmacologic study of irinotecan in combination with cisplatin for advanced lung cancer.

We have conducted a Phase I trial to determine the maximum tolerated dose of CPT-11 together with a fixed dose of cisplatin in patients with advanced lung cancer, and the dose-limiting toxicities of this combination. Fourteen previously untreated patients with stage IIIB or IV disease were treated with CPT-11 (90-min intravenous infusion on days 1, 8, and 15) plus cisplatin (60 mg m-2, intravenously on day 1). The starting dose of CPT-11 was 60 mg m-2, and diarrhea was the dose-limiting toxicity at the 90 mg m-2 dose level. All three patients (all four cycles) given 90 mg m-2 of CPT-11 experienced grade 3 diarrhea. Hematologic toxicity was relatively mild. Elimination of CPT-11 was biphasic with a mean (+/- s.d.) beta half-life of 11.36 +/- 7.26 h. The mean terminal half-life of the major metabolite (7-ethyl-10-hydroxycamptothecin; SN-38) was 22.13 +/- 13.28 (s.d.) h, and modest escalation of the CPT-11 dose from 80 mg m-2 to 90 mg m-2 resulted in a statistically significant apparent increase in the plasma concentrations of SN-38. There were one complete response (7%) and five partial responses (36%) among the 14 patients for an overall response rate of 43%. The recommended dose for Phase II studies is 80 mg m-2 of CPT-11 and 60 mg m-2 of cisplatin.

Adult↗
PubMed1993

Enhanced antitumor efficacy of a combination of CPT-11, a new derivative of camptothecin, and cisplatin against human lung tumor xenografts.

The objective of this study was to evaluate the antitumor efficacy of combined use of 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11) and cisplatin (CDDP). The antitumor activities of CPT-11, CDDP and their combination against 3 human lung tumor xenografts were estimated using congenitally athymic BALB/c (nu/nu) mice. The doses were 47 mg/kg for CPT-11 and 6 mg/kg for CDDP on days 1, 5 and 9. In combination therapy, half of the single dosage of each agent was used. The doses were administered intraperitoneally. The antitumor activity and toxicity were evaluated in terms of the tumor volume and body weight change of mice, respectively. The combination therapy resulted in a statistically significant tumor regression compared to the use of only CPT-11 or CDDP in two tumor xenografts out of three. The toxicity of the combination therapy was no higher than that of CPT-11 or CDDP alone. These results suggest that the antitumor activity of the combination of CPT-11 and CDDP is superior to that of CPT-11 or CDDP alone.

Animals↗
PubMed1993

Activity of the carbapenem panipenem and role of the OprD (D2) protein in its diffusion through the Pseudomonas aeruginosa outer membrane.

Evidence of permeation of panipenem through the OprD (D2) channel of Pseudomonas aeruginosa outer membrane was shown by using OprD protein-producing and -nonproducing strains which contained plasmid pHN4, which codes for L-1 beta-lactamase of Xanthomonas maltophilia. Permeation by panipenem was determined by measuring hydrolysis of the carbapenem by beta-lactamase in the periplasmic space. Permeation by panipenem was also determined by counting uptake of [14C]panipenem into P. aeruginosa PAO1 and its OprD protein-deficient mutant, and this permeation of PAO1 was inhibited by L-lysine. These results indicate that panipenem, as well as imipenem, uses the OprD channel, which functions as a specific channel for diffusion of basic amino acids. Panipenem and imipenem showed stronger activities against PAO1 and clinical isolates in human serum than in Mueller-Hinton broth, which contains more amino acids than human serum does. The activities of the carbapenems were reduced by addition of L-lysine to human serum. Similar results were obtained with mouse serum and ascitic fluid. In contrast, such a change in the activities of carbapenems was not observed with an OprD protein-deficient mutant, suggesting that the main reason for the strong activities of carbapenems in biological fluids is a decrease in competition between the antibiotics and basic amino acids for permeation through the OprD channel. Panipenem and imipenem showed much stronger therapeutic efficacies against experimental infections with P. aeruginosa in mice than did the reference antibiotics. Their in vivo activities were more consistent with their MICs in biological fluids than with those in Mueller-Hinton broth.

Animals↗
PubMed1993

Amodal completion as another perception of color-spreading stimuli.

We made a solid three-dimensional object of the Redies-Spillmann figure and found two kinds of completely different phenomena. First, transparent color-spreading was observed in the empty space around the object. Second, another perceptual organization occurred: observers perceived a cross as a cross-shaped slit through which to see, and then they perceived spreading color disappear entirely. They reported an apparent opaque occluding surface which was localized at the same depth as the slit but was in fact the background. They also reported a colored circle which was mostly occluded by the surface with a cross-shaped slit. We interpreted the circle as being amodally completed in the sense described by Kanizsa in 1955. Even when the figure was drawn on a piece of paper, we observed these two perceptions. We examined whether other stimuli causing neon color-spreading lead to reports of the perception for the Redies-Spillmann figure and found that all the stimuli we examined led to reports of the same kind of perception. Interestingly, the shape of color-spreading was the same as that of the amodal completion.

Attention↗
PubMed1993

Proteins of the vitelline membrane of quail (Coturnix coturnix japonica) eggs.

Proteins in the vitelline membrane of quail (Coturnix coturnix japonica) eggs were analyzed by SDS-PAGE. Ten major bands, molecular mass ranging from 14.5 to 285 kDa, can be clearly distinguished. Two bands corresponding to the molecular masses of 33 and 175 kDa were detected in the inner layer of the membrane and both were stained with periodic acid-Schiff reagent, indicating that they are glycoproteins. Nine bands were detected in the outer layer of the membrane. Among them, 265- and 285-kDa bands were glycoproteins. During storage of eggs at 25 C, the yolk index significantly decreased. Among the 10 proteins of the vitelline membrane, a decrease in the 20-kDa protein was most prominent, disappearing after 5 days of storage. The 16.5- and 175-kDa protein bands were also less prominent, whereas the 40- and 61-kDa proteins increased during storage. These changes in the proteins of the vitelline membrane were also observed in eggs stored at 4 C, although the changes occurred more slowly than that noted from the eggs stored at 25 C.

Analysis of Variance↗