Biomedical subjects
Publications and source records attributed to M Muro.
Conservationists have long contended, largely in impressionistic terms, that 70 years of American dam building and water diversion have destroyed the biological richness of the Colorado River delta, a key nursery of marine life at the end of the Southwest's great watercourse. Now researchers have confirmed those suspicions, using an important ecological player--clams--as a quantitative marker.
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CD28/CTLA-4 interactions with their specific B7-ligands (CD80 and CD86) have decisive roles in antigenic and allogenic responses. Recently, experimental transplant studies demonstrated that donor-specific tolerance is achieved by blocking these interactions. The present study analyzes the expression of these co-stimulatory molecules in peripheral blood cells from 74 liver recipients and in 16 liver biopsies, which were classified into acute-rejection (AR, n = 27) and nonacute-rejection (NAR, n = 47) groups, as well as their influence on the in vitro response of in vivo allosensitized cells. The results clearly indicate that in human liver transplant too, B7 and CD28/CTLA-4 expression on B and CD4(+) peripheral lymphocytes respectively, contributes to graft acceptance or rejection, and appears to be of crucial importance in modulating the host alloresponse and specific-CTL generation. In the NAR-group, costimulatory molecule expression remained at basal levels after transplant, whereas in the AR-group these molecules were significantly upregulated on days of AR. CTLA-4 was observed in the infiltrating lymphocytes in most of the biopsies, but CD80 or CD86 were not. Moreover, specific cytotoxicity from the in vivo primed cells was clearly suppressed in the NAR-patients with low co-stimulatory molecule expression, whereas this activity was not modified but rather stimulated in the AR-group. Together, these findings indicate that intervention of CD28/CTLA-4/B7 signaling could be therapeutically useful in clinical transplantation.
In several studies the HLA system has been implicated in the development of asthma, but the importance of the associations between HLA genes and asthma remains unclear. The aim of this study was to determine the HLA class I and II phenotypic frequencies in a population of asthmatics, and to analyse the relationship between these phenotypes and any type of asthma. We typed HLA class I and II antigens in a series of 189 asthmatic individuals (102 atopic and 87 non-atopic), and in a control population of 150 unrelated healthy Caucasoid donors. When the HLA phenotypic frequencies were compared, no statistical differences were found. Therefore, no definitive HLA association could be established with atopic or non-atopic asthma in the studied population. Abbreviations AA, atopic asthma; FEV1, forced expiratory volume in 1 s; NAA, non-atopic asthma; PCR, polymerase chain reaction; SSOP, sequence-specific oligonucleotide probes; SPT, skin prick test.
A new periodogram was proposed using one-way analysis of variance (ANOVA), termed ANOVA periodogram, in order to reveal a precise significant periodicity. Thirty 3-day complex computer-simulated time series with known periodicity (24 h) and three 2-h data-missing occurring periodically (23 h, 20 min) were used to compare the ANOVA periodogram with Enright's one. In results, the ANOVA periodogram was superior to Enright's periodogram in the accuracy of assessing the major periodicity.
A rare case of paraesophageal hernia with complete intrathoracic incarceration of the stomach after laparoscopic Nissen fundoplication is described. An 85-year-old woman who had undergone laparoscopic Nissen fundoplication for gastroesophageal reflux disease presented 14 months later with nausea and vomiting. Esophagogastroendoscopy showed obstruction of the esophagogastric junction and gastric mucosal necrosis. Emergency laparotomy showed the stomach to be entirely strangulated into the thorax, with areas of necrosis. Gastrotomy was followed by resection of the necrotic anterior wall of the stomach, closure of the hiatus, and suturing of the stomach to the diaphragm. Appropriate closure of crura and anchoring suture between the stomach and diaphragm are helpful to prevent recurrent hernia after laparoscopic Nissen fundoplication.
We have reported that the macrophage-like cell line J774.1, when infected with the periodontopathic bacterium Actinobacillus actinomycetemcomitans, undergoes apoptosis. In this study, we examined whether stimulation of J774.1 cells with lipopolysaccharide (LPS) before the infection affects the subsequent apoptosis. Cytotoxicity on the LPS-stimulated cells was about half of the unstimulated control cells. DNA fragmentation in the LPS-stimulated cells was also significantly lower than in the control cells, whereas it was increased to a level similar to that of the control cells by addition of a nitric oxide (NO) inhibitor. In addition, significantly smaller numbers of live A. actinomycetemcomitans were recovered from the LPS-stimulated macrophages at 8 h after the infection as compared with the control cells. These findings suggest that the inhibitory effect of LPS on apoptosis results from an enhanced NO-mediated bactericidal activity.
The prenatal diagnosis of peroxisomal D-3-hydroxyacyl-coenzyme A (CoA) dehydratase/D-3-hydroxyacyl-CoA dehydrogenase bifunctional protein (D-BP) deficiency was performed by peroxisomal beta-oxidation assay, indirect immunofluorescence staining, immunoblot analysis, and gene analysis of cultured amniocytes obtained from a fetus at 16 weeks' gestational age. beta-Oxidation activity, measured by [1-14C] lignoceric acid oxidation, was markedly decreased compared with the controls. Large peroxisomes were readily identified by immunofluorescence staining with anti-human catalase, as was found in the reported patients. Immunoreactive D-BP material was absent on immunoblot analysis and immunofluorescence staining with anti-human D-BP. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis revealed the presence of the same 237-bp deletion in the cDNA as that detected in a sibling (the proband). The autopsied fetus showed the characteristic facial appearance and D-BP was deficient on immunoblot and immunohistopathological studies of the fetal tissues. No neuronal migration disorder was identified. This seems to be the first prenatal diagnosis of D-BP deficiency.
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Membrane HLA class-I expression (mHLA-I), soluble HLA class-I antigens (sHLA-I) and interleukin (IL)-10 are different factors implicated in the special acceptance of liver allograft. In this study, pre- and post-operative levels of mHLA-I in peripheral blood lymphocytes (PBL) and serum sHLA-I were analyzed in 86 liver transplants, immunosuppressed with Cyclosporine-A, methylprednisolone and azathioprine, and classified into acute-rejection (AR, n = 28) and non-acute-rejection (NAR, n = 58) groups. Serum IL-10 was studied in 47 recipients (AR-group, n = 16 and NAR-group, n = 31). Pre-transplant values of mHLA-I and sHLA-I showed a bimodal distribution (high/low) in NAR-recipients, but in AR-patients were mainly included in the low expression/secretion zone (mHLA-I, p < 0.02 and sHLA-I, p < 0.05). Consequently, average pre-transplant mHLA-I (868 +/- 109 versus 998 +/- 123, p < 0.05) and sHLA-I (1.3 +/- 0.4 versus 2.02 +/- 0.7 microg/ml, p < 0.01) was lower in the AR- than in the NAR-group. After transplant both parameters decreased in the NAR-group, but increased in AR-recipients previous to and on rejection diagnosis day. Additionally, serum IL-10 levels were significantly higher (p < 0.01) in the NAR than in the AR-group during the first 24 h post-transplant. In conclusion, low pre-transplant mHLA-I and sHLA-I levels pre-dispose liver recipients to acute rejection, whereas early post-transplant increases of serum IL-10 appear to be related to a good liver allograft acceptance.
Laparoscopic low anterior resections using a triple stapling technique in five patients with rectal cancers (four Dukes A and one Dukes C) were performed. The location of the tumors was between 5 and 18 cm from the anal verge. For easy maneuverability, a 33-mm suprapubic port was used. In this technique, the Endo TA (the first stapler) is applied at the distal margin of the rectum to occlude the bowel. The bowel is irrigated with povidone-iodine solution and transected by an endolinear (the second) stapler. Anastomosis is completed by firing the circular (the third) stapler. The operative time was 177 +/- 28.0 minutes, estimated blood loss was 41.7 +/- 28.6 g, and flatus appeared 1.8 +/- 0.8 days after surgery. Follow-up studies have showed no local recurrence or distant metastasis. This procedure is safe and useful for performing laparoscopic low anterior resection.
The aim of the present study is to reveal gestational age-related changes in sustained foetal tachycardia (SFT). 24 h fetal heart rate (FHR) recordings were made on 102 normal pregnant women in 30-41 weeks of gestation. SFT was defined as an increase for 20 or more beats per minute from the FHR-baseline persisting for more than 20 min. In the results, SFTs in 38-39 weeks started during night-time (1900-0700) more frequently than during day-time (0700-1900) (P < 0.01, by chi-square test). The rate and duration were 0% and 0 min in 30-31 weeks of gestation, and increased to 85% and 114 min in 40-41 weeks, respectively. Two critical points were detected by a piecewise linear regression analysis: in the rate between 34-35 weeks and 36-37 weeks, and in the duration between 38-39 to 40-41 weeks. We conclude that gestational age-related changes in SFT depend on the developmental stages.
BACKGROUND: Acute rejection in liver transplants is one of the commonest causes of liver dysfunction in the early postoperative period. However, the factors involved in liver graft rejection are still unknown. Our study was aimed at ascertaining whether the degree of HLA class I and class II compatibility or pretransplant viral infection have any influence on early acute liver graft rejection. METHODS: We reviewed clinical and laboratory data in 190 consecutive patients who underwent a liver transplant. HLA-A, HLA-B, and HLA-DR typing for the establishment of an HLA match score was performed by a standard microcytotoxicity method. The existence of pretransplant viral infection was investigated in sera and biopsy tissue by serologic (hepatitis B virus, hepatitis C virus) and polymerase chain reaction (cytomegalovirus) techniques, respectively. The influence of these two factors in acute rejection and the interaction between them was also analyzed. RESULTS: A strong association between viral infection and acute rejection in the group with partial class I matching was found (odds ratio=7.75; P<0.0009), whereas no correlation was observed in the group with zero class I matching (odds ratio=0.98; P=0.81). The rejection percentage in the group in which partial class I match and viral infections coexisted was 60%, whereas in the partially class I-matched group without pretransplant viral presence it was 16%. CONCLUSIONS: These findings suggest a participation of partial HLA class I compatibility in triggering acute rejection in recipients suffering preoperative viral infections and support the idea that HLA class I antigen matching could play a role as a linking element between the MHC-restricted T cell-mediated response to viral infection and the allogenic response in liver transplantation.
We have previously reported the evidence for apoptosis in the mouse macrophage cell line J774.1 by the periodontopathic bacterium Actinobacillus actinomycetemcomitans. In this study, we examined the role of protein kinases in the induction of apoptosis in A. actinomycetemcomitans-infected J774.1 cells by the MTT assay, fluorescence microscopy and flow cytometric analysis. After J774.1 cells were precultured with protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA), J774.1 cells infected with A. actinomycetemcomitans showed the increased percentage of apoptotic cells. On the contrary, protein kinase A (PKA) activators, such as forskolin and dibutyryl cAMP, do not mimic the effect of PMA. PKC inhibitors, such as staurosporine, calphostin C, chelerythrine chloride, and H7 were found to suppress apoptotic cell death in J774.1 cells infected with A. actinomycetemcomitans. However, HA1004, known as PKA inhibitor, had no effect on apoptosis in infected macrophages. The results presented here suggest that the signals through PKC may play crucial roles in the modulation of apoptosis in macrophages infected with A. actinomycetemcomitans.
The granulocytic antigens NA1 and NA2 are two allelic gene products of the FcgammaRIIIB gene. These antigens are frequently targets of granulocytic-specific allo-antibodies and auto-antibodies that cause neutropenias. Different distributions of these antigens have been found in population studies. In our study, the genomic DNA of 345 healthy, unrelated Spanish individuals was typed for NA1 and NA2 using polymerase chain reaction (PCR) with sequence-specific primers (SSP). The gene frequencies found in the Spanish population were 0.29 for NA1 and 0.71 fo NA2. Flow cytometry immunotyping was also carried out in 20 of these samples, and an exact correlation was observed among the results. The gene frequencies determined in our study are similar to those reported in other Caucasian populations. The null phenotype reported in other serological studies was not found. This typing system can be used in population studies instead of serological tests as a more rapid, simple and reproducible method.
The diurnal change in baseline fetal heart rate (FHR) of four anencephalic fetuses at 20, 23, 24 and 30 weeks of gestation were examined. The mean baseline FHR in 00.00-06.00 h, 06.00-12.00 h, 12.00-18.00 h and 18.00-24.00 h were compared by one-factor ANOVA and Scheffe's test in each case. The diurnal variations in baseline FHR were recognized in all subjects (P < 0.01). In 3/4 subjects, the lowest values were at 00.00-06.00 h. The diurnal variation in baseline FHR might be caused by maternal factors because it was present even in the anencephalic fetuses that had no central nervous system having the oscillators of the circadian rhythm.
BACKGROUND: Our aim was to investigate the relationship between placental location and resistance index (RI) of uterine arteries in cases with intrauterine growth retardation (IUGR). METHODS: Placental location and flow velocity waveforms of uterine arteries in 86 normal and 20 IUGR cases from 33 to 38 weeks of gestation were examined using a combined real-time scanner and pulsed Doppler ultrasonography. The location of placenta was classified as lateral when most of it was located to either the right or the left side of the uterine midline. Otherwise it was called central. Cases where the placenta was located in the uterine fundus or in the lower segment were not included. RI values were calculated from the uterine arteries on the placental side, on the non-placental side and in case of central placentas as a mean of both uterine arteries. In normal cases, the calculations were done every second week from 33 to 38 weeks of gestation, and the difference in variance among three gestational ages in each artery was tested by a one-way ANOVA. In IUGR cases, a standard deviation score (SDS) was calculated individually in each artery as (RI - normal mean)/normal SD. Differences in SDS between three categories of uterine arteries were examined by non-parametric tests. RESULTS: In normal cases, there was no significant difference in variance of RIs among three gestational ages in each category of arteries. In IUGR cases, SDSs on the placental side were higher than those on the non-placental side and those in central placenta, (p<0.01, Wilcoxon's and Mann Whitney's tests, respectively). SDSs in five of eight cases with central placentas were below 1.0. Two of 12 cases with lateral placentas had higher SDSs on the non-placental side than on the placental side and resulted in abruptio placentae. CONCLUSIONS: Deviation of RIs in uterine arteries with IUGR could be affected by the pathologic conditions of the utero-placental blood flow on the placental side of lateral placenta rather than in central placenta and might be done by dramatic increase in resistance to flow of the myometrial vessels on the non-placental side.