Comprehensive genotyping analysis of single nucleotide polymorphisms responsible for beef marbling in Japanese Black cattle

BACKGROUND

Beef marbling is considered a desirable trait in the meat industry. Therefore, understanding the genetic factors that cause marbling is important. Previously, we performed a genome-wide association study to examine genetic factors associated with beef marbling in Japanese Black cattle and identified a candidate region between 10-30 Mbp on chromosome 7. We verified the effect of the SNPs in this region on beef marbling using linkage disequilibrium block analysis. We narrowed down the candidate region to a range of 15.8-16.1 Mbp. In this study, we comprehensively detected all of the SNPs in this region and verified their effects on beef marbling.

RESULTS

Genome resequencing using four animals exhibiting high beef marbling standard (BMS) and four with low BMS revealed a total of 1,846 polymorphisms within the candidate region. Based on the annotation, we selected 13 SNPs exhibiting a moderate impact, as no high-impact SNPs were detected. All of the SNPs represented missense polymorphisms and were located in the following seven genes: RDH8, ANGPTL6, DNMT1, MRPL4, ICAM1, ICAM3, and ICAM5. Finally, we determined the effects of these SNPs on the BMS of a Japanese Black cattle population (n = 529). Analysis of variance revealed that the five SNPs were located in genes encoding the intercellular adhesion molecules (ICAM1, ICAM3, and ICAM5), and showed a highly significant association compared with the remainder (p < 0.01). The lowest p-value was observed for ICAM3_c.739G > A (p = 1.18E-04). Previous studies have suggested that intercellular adhesion molecules (ICAM) may be an upstream factor that regulates adipocyte differentiation. Therefore, considering the polymorphism and putative gene function, we suggest that ICAM1 is potentially responsible for beef marbling. c.470C > G and/or c.994G > A on ICAM1 may be responsible for this quantitative trait locus.

CONCLUSIONS

Promising SNP candidates responsible for beef marbling were identified using extensive polymorphism verification in a previously reported QTL region. We aim to elucidate the mechanism of beef marbling in future studies by investigating how these polymorphisms alter protein structure and function.

Verification of Candidate SNP Effects Reveals Two QTLs on BTA7 for Beef Marbling in Two Japanese Black Cattle Populations

In our previous study, we used genome resequencing to detect all candidate polymorphisms within a quantitative trait loci (QTL) region for beef marbling reported previously at 10–30 Mbp on bovine chromosome 7, and we selected 6044 polymorphisms as candidate quantitative trait nucleotides (QTNs). In the present study, we aimed to identify quantitative trait genes (QTGs) and QTNs in this QTL region by verifying the effect of SNPs on beef marbling in two Japanese Black cattle populations using a Dynamic Array integrated fluidic circuit. In total, 96 selected SNPs were genotyped in 441 and 529 animals in Hyogo and Miyazaki cattle populations, respectively. The most significant p-values were detected in a SNP in a splice region of ALDH7A1 (SNP93_ALDH7A1; p = 3.46 × 10−5) in Hyogo cattle and a missense polymorphism of intercellular adhesion molecule-1 (ICAM1) (SNP37_ICAM1; p = 3.33 × 10−4) in Miyazaki cattle. Interestingly, SNP93_ALDH7A1 was not significant (p = 0.459) in Miyazaki cattle, and SNP37_ICAM1 showed a weakly significant association (p = 0.043) in Hyogo cattle. Thus, each population would likely have different QTGs and QTNs for beef marbling in the QTL region. In the Hyogo population, it was not possible to determine the accurate range of the linkage disequilibrium (LD) block in LD block analysis because of a strong LD structure throughout the assessed region. In Miyazaki cattle, however, an LD block containing SNP37_ICAM1 had a range of 15.8–16.1 Mbp, suggesting that QTNs would be located within this region. The functions of 19 genes in the LD block were investigated. ICAM1 is known to play an important role in adipocyte differentiation; given this function and the effect of amino acid substitution, SNP37_ICAM1 was identified as a promising candidate QTN for beef marbling. Further research on the effect of SNP37_ICAM1 on adipocyte differentiation is expected to provide insights into the mechanism underlying beef marbling formation.

Geographical contrasts of Y-chromosomal haplogroups from wild and domestic goats reveal ancient migrations and recent introgressions

By their paternal transmission, Y-chromosomal haplotypes are sensitive markers of population history and male-mediated introgression. Previous studies identified biallelic single-nucleotide variants in the SRY, ZFY, DDX3Y genes, which in domestic goats identified four major Y-chromosomal haplotypes Y1A, Y1B, Y2A and Y2B with a marked geographic partitioning. Here, we extracted goat Y-chromosomal variants from whole-genome sequences of 386 domestic goats (75 breeds) and 7 wild goat species, which were generated by the VarGoats goat genome project. Phylogenetic analyses indicated domestic haplogroups corresponding to Y1B, Y2A and Y2B, respectively, whereas Y1A is split into Y1AA and Y1AB. All five haplogroups were detected in 26 ancient DNA samples from southeast Europe or Asia. Haplotypes from present-day bezoars are not shared with domestic goats and are attached to deep nodes of the trees and networks. Haplogroup distributions for 186 domestic breeds indicate ancient paternal population bottlenecks and expansions during the migrations into northern Europe, eastern and southern Asia and Africa south of the Sahara. In addition, sharing of haplogroups indicates male-mediated introgressions, most notably an early gene flow from Asian goats into Madagascar and the crossbreeding that in the 19^th century resulted in the popular Boer and Anglo-Nubian breeds. More recent introgressions are those from European goats into the native Korean goat population and from Boer goat into Uganda, Kenya, Tanzania, Malawi and Zimbabwe. This study illustrates the power of the Y-chromosomal variants for reconstructing the history of domestic species with a wide geographic range.

Phylogenomics and Spatiotemporal Dynamics of Bovine Leukemia Virus Focusing on Asian Native Cattle: Insights Into the Early Origin and Global Dissemination

Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis, is currently one of the most important pathogens affecting the cattle industry worldwide. Determining where and in which host it originated, and how it dispersed across continents will provide valuable insights into its historical emergence as the cattle pathogen. Various species in the Bos genus were domesticated in Asia, where they also diversified. As native cattle (taurine cattle, zebu cattle, yak, and water buffalo) are indigenous and adapted to local environments, we hypothesized that Asian native cattle could have harbored BLV and, therefore, that they were important for virus emergence, maintenance, and spread. In this study, phylogeographic and ancestral trait analyses—including sequences obtained from Asian native cattle—were used to reconstruct the evolutionary history of BLV. It was shown that, since its probable emergence in Asia, the virus spread to South America and Europe via international trade of live cattle. It was inferred that zebu cattle were the hosts for the early origin of BLV, while taurine cattle played the significant role in the transmission worldwide. In addition, the results of positive selection analysis indicate that yak had a substantially minor role in the transmission of this virus. In this study, endogenous deltaretrovirus sequences in bats, collected in Asian countries, were also analyzed on whether these sequences were present in the bat genome. Endogenous deltaretrovirus sequences were detected from bat species endemic to specific regions and geographically isolated for a long time. Endogenous deltaretrovirus sequences from these geographically isolated species represent ancient exogenous deltaretroviruses distributions. The phylogenetic analysis revealed that these newly obtained endogenous deltaretrovirus sequences were closely related to those of BLV from Asian native cattle, indicating that BLV-related ancient deltaretroviruses circulated in Asia long before the emergence of BLV. Together, our analyses provide evidence for origin and spatiotemporal dynamics of BLV.

Comprehensive assessment of genetic diversity, structure, and relationship in four Japanese cattle breeds by Illumina 50 K SNP array analysis

There are four unique cattle breeds in Japan: Japanese Black, Japanese Brown, Japanese Polled, and Japanese Shorthorn. The objective of this study was to comprehensively assess the genetic diversity, structure, relationship, and the degree of influence from foreign breeds (Angus, Simmental, Hanwoo, Shorthorn, Ayrshire, Brown Swiss, and Devon) in the Japanese cattle breeds using Illumina 50 K SNP array. In principal component analysis, each Japanese breed was separately clustered except for Japanese Shorthorn and Shorthorn. Japanese cattle breeds also showed different genetic components from each other at K ≥ 5 in population structure analysis. Japanese Shorthorn, on the other hand, had a very similar structure to Shorthorn at K ≤ 9, and Japanese Polled had a partially similar component with Angus at K = 3-7. Such close relationships were also observed in the phylogenetic tree. These findings imply that Japanese cattle breeds share genetic components with European cattle breeds to some extent while they have been almost differentiated. In population structure analysis, Japanese Black cattle shared little genetic component (3.5%) with European breeds. This is the first study to determine the extent to which European breeds impact Japanese breeds.

FGF5 and EPAS1 gene polymorphisms are associated with high-altitude adaptation in Nepalese goat breeds

Several studies have reported the gene polymorphisms associated with high-altitude adaptation in goats. The FGF5 gene is a regulator in the hair-growth and a SNP c.-253G>A located within 5'UTR has been reported to cause long-haired phenotype. The EPAS1 gene is a transcription factor for various genes that have hypoxia-adaptive functions and a nonsynonymous SNP (Q579L) located in exon 5 has been reported to be associated with the mean corpuscular hemoglobin concentration. Nepal has large difference in altitudes in the north-south direction and four indigenous goat breeds are bred depending on the altitude. We used a total of 130 animals in Nepal, Chyangra (n = 37), Sinhal (n = 24), Khari (n = 33), and Terai (n = 36), and genotyped these two gene polymorphisms to compare the gene frequencies among the breeds and investigate the associations between breeding altitudes and allele frequencies. The genotyping results revealed that the mutant allele frequency in both polymorphisms tended to increase, as the breeding altitude of each population increased. In addition, correlation coefficients showed a relatively strong positive correlation between the breeding altitude and the mutant allele frequencies (r = 0.87 in FGF5 and r = 0.68 in EPAS1). These results suggested that both polymorphisms would significantly contribute to the high-altitude adaptation in Nepalese goat breeds.

Cattle mitogenome variation reveals a post-glacial expansion of haplogroup P and an early incorporation into northeast Asian domestic herds

Surveys of mitochondrial DNA (mtDNA) variation have shown that worldwide domestic cattle are characterized by just a few major haplogroups. Two, T and I, are common and characterize Bos taurus and Bos indicus, respectively, while the other three, P, Q and R, are rare and are found only in taurine breeds. Haplogroup P is typical of extinct European aurochs, while intriguingly modern P mtDNAs have only been found in northeast Asian cattle. These Asian P mtDNAs are extremely rare with the exception of the Japanese Shorthorn breed, where they reach a frequency of 45.9%. To shed light on the origin of this haplogroup in northeast Asian cattle, we completely sequenced 14 Japanese Shorthorn mitogenomes belonging to haplogroup P. Phylogenetic and Bayesian analyses revealed: (1) a post-glacial expansion of aurochs carrying haplogroup P from Europe to Asia; (2) that all Asian P mtDNAs belong to a single sub-haplogroup (P1a), so far never detected in either European or Asian aurochs remains, which was incorporated into domestic cattle of continental northeastern Asia possibly ~ 3700 years ago; and (3) that haplogroup P1a mtDNAs found in the Japanese Shorthorn breed probably reached Japan about 650 years ago from Mongolia/Russia, in agreement with historical evidence.

Indonesian native goats (Capra hircus) reveal highest genetic frequency of mitochondrial DNA haplogroup B in the world

The objective of this study was to determine mtDNA sequences of the 481 bp HV1 region from two Indonesian native goat breeds, Kacang and Marica, to confirm the phylogeographic distribution of caprine haplogroup B in Southeast Asia. Based on these sequences, 12 haplotypes were observed and categorized into the predominant haplogroup B and minority haplogroup A, indicating that Indonesian native goats present the highest frequency (0.950) of the haplogroup B in the world. These results strongly emphasize previous observations of the haplogroup B frequencies tending to increase southeastward in Southeast Asia. Additionally, this suggests that goats primary bred into Southeast Asia might predominantly carry haplogroup B. This could essentially contribute to the understanding of the origin, propagation route and/or introgression history of Southeast Asian goats.

Detection of candidate polymorphisms around the QTL for fat area ratio to rib eye area on BTA7 using whole-genome resequencing in Japanese Black cattle

In our previous study, we performed genome-wide association study (GWAS) to identify the genomic region associated with Fat area ratio to rib eye area (FAR) and detected a candidate in BTA7 at 10-30 Mbp. The present study aims to comprehensively detect all polymorphisms in the candidate region using whole-genome resequencing data. Based on whole-genome resequencing of eight animals, we detected 127,090 polymorphisms within the region. Of these, 31,945 were located within the genes. We further narrowed the polymorphisms to 6,044 with more than five allele differences between the high and low FAR groups that were located within 179 genes. We subsequently investigated the functions of these genes and selected 170 polymorphisms in eight genes as possible candidate polymorphisms. We focused on SLC27A6 K81M as a putative candidate polymorphism. We genotyped the SNP in a Japanese Black population (n = 904) to investigate the effect on FAR. Analysis of variance revealed that SLC27A6 K81M had a lower p-value (p = .0009) than the most significant SNP in GWAS (p = .0049). Although only SLC27A6 K81M was verified in the present study, subsequent verification of the remaining candidate genes and polymorphisms could lead to the identification of genes and polymorphisms responsible for FAR.

Effect of DNA markers on the fertility traits of Japanese Black cattle for improving beef quantity and quality

Carcass traits have been efficiently improved by recent selection using DNA markers in beef cattle. Additionally, DNA markers might have an effect on other traits such as fertility traits; therefore attention should also be paid to such pleiotropic effects. However, the effects of the markers on both carcass and fertility traits have never been evaluated in the same population, since they are generally measured in different populations. The objective in the current study was to discuss effectiveness of DNA markers developed for carcass traits through investigation of their effects on carcass and fertility traits in a population. We genotyped six markers SCD V293A, FASN g.841G>C, PLAG1 g.49066C>G, NCAPG I442M, DGAT1 K232A, and EDG1 g.1471620G>T in a Japanese Black cattle population (n=515). To investigate their effects on carcass and fertility traits, we performed statistical analysis (ANOVA and the Tukey–Kramer honestly significant difference (HSD) test). In the results, three of six markers, SCD V293A, NCAPG I442M, and EGD1 g.1471620G>T, were significantly associated with both carcass and fertility traits. Remarkably, the same allele for each marker had positive effects on both traits, suggesting that we would be able to simultaneously improve them using these markers in this population. However, previous studies reported that the effects of DNA markers could differ among populations. Therefore, it is necessary to confirm the effect of the marker in each population before it is used for improvement.

Whole-genome resequencing to identify candidate genes for the QTL for oleic acid percentage in Japanese Black cattle

In our previous study, we detected a QTL for the oleic acid percentage (C18:1) on BTA9 in Japanese Black cattle through a genome-wide association study (GWAS). In this study, we performed whole-genome resequencing on eight animals with higher and lower C18:1 to identify candidate polymorphisms for the QTL. A total of 39,658 polymorphisms were detected in the candidate region, which were narrowed to 1993 polymorphisms within 23 genes based on allele differences between the high and low C18:1 groups. We subsequently selected three candidate genes, that is, CYB5R4, MED23, and VNN1, among the 23 genes based on their function in fatty acid metabolism. In each candidate gene, three SNPs, that is, CYB5R4 c.*349G > T, MED23 c.3700G > A, and VNN1 c.197C > T, were selected as candidate SNPs to verify their effect on C18:1 in a Japanese Black cattle population (n = 889). The statistical analysis showed that these SNPs were significantly associated with C18:1 (p < 0.05), suggesting that they were candidates for the QTL. In conclusion, we successfully narrowed the candidates for the QTL by detecting possible polymorphisms located within the candidate region. It is expected that the responsible polymorphism can be identified by demonstrating their effect on the gene's function.

The Eurasian Steppe is an important goat propagation route: A phylogeographic analysis using mitochondrial DNA and Y-chromosome sequences of Kazakhstani goats

Goats (Capra hircus) were domesticated in the Fertile Crescent and propagated all over the world. The Silk Road through the Eurasian Steppe belt is a possible propagation route for domestic goats to Central Asia. Kazakhstan is in close geographical proximity to domestication centers and covers the majority of the Eurasian Steppe belt. In this study, we examined the genetic diversity and phylogeographic structure of Kazakhstani goats. The mtDNA sequences of 141 Kazakhstani goats were categorized into haplogroups A, C, and D, of which haplogroup A was predominant (97%), whereas haplogroups C and D were detected at low frequencies (1.4% each). The Kazakhstani haplotypes C were thzen categorized into Asian mtDNA type. Sequence analysis of the SRY gene on the Y-chromosome in 67 male Kazakhstani goats revealed two haplotypes: Y1A (64%) and Y2A (36%). Analysis of the distribution of mtDNA haplogroups and SRY haplotypes from Eurasia and Africa demonstrated genetic similarity among animals from Kazakhstan, Mongolia, and Northwest China located on the Eurasian Steppe belt. These phylogeographic results suggested that the Eurasian Steppe belt was an important propagation route for goats to Central Asia.

Kazakhstani native cattle reveal highly divergent mtDNA from Bos taurus and Bos indicus lineages with an absence of Bos indicus Y chromosome

Kazakhstan is the largest landlocked country and contains two important propagation routes for livestock from the Fertile Crescent to Asia. Therefore, genetic information about Kazakhstani cattle can be important for understanding the propagation history and the genetic admixture in Central Asian cattle. In the present study, we analyzed the complete mtDNA D-loop sequence and SRY gene polymorphism in 122 Kazakhstani native cattle. The D-loop sequences revealed 79 mitochondrial haplotypes, with the major haplogroups T and I. The Bos taurus subhaplogroups consisted of T (3.3%), T1 (2.5%), T2 (2.5%), and T4 (0.8%) in addition to the predominant subhaplogroup T3 (86.9%), and the Bos indicus subhaplogroup of I1 (4.1%). Subsequently, we investigated the paternal lineages of Bos taurus and Bos indicus, however, all Kazakhstani cattle were shown to have Y chromosome of Bos taurus origin. While highly divergent mtDNA subhaplogroups in Kazakhstani cattle could be due to the geographical proximity of Kazakhstan with the domestication center of the Fertile Crescent, the absence of Bos indicus Y chromosomes could be explained by a decoupling of the introgression dynamics of maternal and paternal lineages. This genetic information would contribute to understanding the genetic diversity and propagation history of cattle in Central Asia.

Application of DNA markers for discrimination between Japanese and Australian Wagyu beef

The objective of this study was to discriminate between original Japanese and Australian Wagyu beef, which is sold in the Singapore markets, using six previously developed DNA markers. To effectively evaluate the six markers for breed identification, the probability of identification as Australian Wagyu beef was calculated based on the estimated allele frequencies using 130 Australian Wagyu individuals. The combined use of six markers would allow the discrimination of Australian Wagyu beef with an estimated probability of 0.776. The probability to discriminate Australian Wagyu from Japanese Wagyu beef was sufficiently high. In addition, Australian Wagyu has maternal mitochondrial DNA of Bos indicus cattle with moderate high frequency of 0.377. The DNA marker system could also be used as a deterrent force against false sales, and contribute to the reduction and prevention of incorrect or falsified labeling of beef.

Identification of leptin gene polymorphisms associated with carcass traits and fatty acid composition in Japanese Black cattle

Previous studies have indicated that some leptin gene polymorphisms were associated with economically important traits in cattle breeds. However, polymorphisms in the leptin gene have not been reported thus far in Japanese Black cattle. Here, we aimed to identify the leptin gene polymorphisms which are associated with carcass traits and fatty acid composition in Japanese Black cattle. We sequenced the full-length coding sequence of leptin gene for eight Japanese Black cattle. Sequence comparison revealed eight single nucleotide polymorphisms (SNPs). Three of these were predicted to cause amino acid substitutions: Y7F, R25C and A80V. Then, we genotyped these SNPs in two populations (JB1 with 560 animals and JB2 with 450 animals) and investigated the effects on the traits. Y7F in JB1 and A80V in JB2 were excluded from statistical analysis because the minor allele frequencies were low (< 0.1). Association analysis revealed that Y7F had a significant effect on the dressed carcass weight in JB2; R25C had a significant effect on C18:0 and C14:1 in JB1 and JB2, respectively; and A80V had a significant effect on C16:0, C16:1, C18:1, monounsaturated fatty acid and saturated fatty acid in JB1. The results suggested that these SNPs could be used as an effective marker for the improvement of Japanese Black cattle.

[Helicobacter pylori: cagA analysis and vacA genotyping in Chile. Detection of a s2/m1 strain]

BACKGROUND

The genes cagA and vacA encode H pylori virulence factors.

AIM

To genotype these genes in H pylori strains isolated from patients with upper gastrointestinal symptoms.

MATERIAL AND METHODS

We studied 50 patients who underwent an upper gastrointestinal endoscopy, with positive culture for H pylori. Detection of cagA and vacA genotyping was done using polymerase chain reactions.

RESULTS

The gene cagA was detected in 19 samples (38%). Signal sequences s1 and s2 of vacA gene were detected in 16 samples each (32%). There was simultaneous amplification of s1 and s2 in 6 samples and they were not detected in 9 samples. The middle region of vacA was m1 in 9 samples, m2 in 29 samples and there was simultaneous amplification of m1 and m2 in 12 samples. In 16 samples (32%), more than one type of signal sequence or medial region was detected. Of those patients in whom vacA was the only genotype detected, 15 were s2/m2, 7 were s1/m1, 4 were s1/m2 and 1 was s2/m1.

CONCLUSIONS

In these patients, the infection with cagA- H pylori strains, predominates, the prevalence of infection with s1 or s2 strains is similar and the predominant medial region is m2.

In vitro antibacterial activity of Chilean red wines against Helicobacter pylori

The antibacterial activity of sixteen Chilean red wines (Cabernet Sauvignon, Cabernet Merlot, Cabernet Organic and Pinot Noir), and the active extracts of two randomly selected wines were assayed for their antibacterial activity on six strains of Helicobacter pylori isolated from gastric biopsies. The active fraction of the wines was obtained by dichloromethane extraction, and the antibacterial activity of the wines and extracts was evaluated by an agar diffusion method. All the red wines studied showed some antibacterial activity on the six strains of H. pylori, although the strains were heterogeneous in their susceptibility to each particular wine. The active fraction of the two wines selected also showed good activity against the strains tested. The main active compound was identified as resveratrol. The results presented indicate that Chilean red wines have antibacterial activity against H. pylori, which depends mainly on the presence of resveratrol.

[In vitro antimicrobial susceptibility of Helicobacter pylori strains: isolation of strains resistant to clarithromycin]

BACKGROUND

Our laboratory has carried out an epidemiological surveillance of Helicobacter pylori antimicrobial susceptibility since 1997.

AIM

To report the antimicrobial susceptibility of H pylori strains, isolated in Chile from August 1997 to August 2000.

MATERIAL AND METHODS

Ninety one H pylori strains, obtained from antral gastric biopsies during upper gastrointestinal endoscopies were studied. Susceptibility towards clarithromycin, amoxicillin, bismuth subcitrate and metronidazole was studied by an agar diffusion technique.

RESULTS

All strains were susceptible to amoxicillin and two strains were resistant to clarithromycin. Forty two percent of strains were resistant to metronidazole and 13% were resistant to bismuth subcitrate.

CONCLUSIONS

These results underscore the need to maintain an epidemiological surveillance of H pylori antimicrobial susceptibility, to modify its eradication therapy accordingly.

Noninvasive cerebral blood volume measurement during seizures using multichannel near infrared spectroscopic topography

Near infrared spectroscopic topography (NIRS) is widely recognized as a noninvasive method to measure the regional cerebral blood volume (rCBV) dynamics coupled with neuronal activities. We analyzed the rCBV change in the early phase of epileptic seizures in 12 consecutive patients with medically intractable epilepsy. Seizure was induced by bemegride injection. We used eight-channel NIRS in nine cases and 24 channel in three cases. In all of the cases, rCBV increased rapidly after the seizure onset on the focus side. The increased rCBV was observed for about 30-60 s. The NIRS method can be applied to monitor the rCBV change continuously during seizures. Therefore, this method may be combined with ictal SPECT as one of the most reliable noninvasive methods of focus diagnosis.

[Factors that affect DNA content analysis by flow cytometry]

DNA ploidy and cell cycle analysis by flow cytometry is used to obtain additional information about the diagnosis and prognosis of different types of cancer. However, there are several disagreements among authors about the tissue source (fresh-frozen or paraffin embedded), cellular dissociation methods (mechanical, enzymatic or other), use of different dyes, lasers, analysis software with different mathematical models and interpretation of results. A discussion about the different aspects that affect the study of DNA ploidy and cell cycle and a consensus in publications is mandatory. A strict control of analysis processes and data interpretation is also necessary.

The pathogenesis of dysplastic kidney in a urinary tract obstruction in the female fetal lamb

BACKGROUND/PURPOSE

The type of renal dysplasia resulting from obstructive uropathy depends on the completeness of the obstruction and its timing with respect to the stage of glomerulogenesis at the time of the obstruction. The authors created a successful obstructive uropathy model in the female fetal lamb to demonstrate the differing pathogenesis of renal dysplasia.

METHODS

Female fetal lambs at 60 and 90 days' gestation had their urethra and urachus ligated transabdominally and were delivered by cesarean section at 145 days (full term). Kidney length and cortical thickness were measured, and samples were examined histologically. In the lambs operated on at 90 days, the urine was collected at delivery and Na and CI were measured and compared with the results obtained from normal full-term lambs.

RESULTS

Seven of 10 female lambs had hydronephrosis or dysplastic kidneys. The cortext to kidney length ratio was 10+/-3% in the 90-days hydronephrotic group versus 29+/-6% in the controls (P<.001). Morphologically, the 90-day model had dilatation of the collecting tubules with normal glomerular numbers. The 60-day model had tubular cysts with fibromuscular cuffing and reduced glomerular numbers. The fetal urine Na was 47+/-3.3 mmol/L in controls versus 78+/-24 mmol/L in the hydropnephrotic lambs (P<.05). The urine CI in these lambs was 38+/-8.6 mmol/L in controls versus 55+/-14.5 mmol/L in the hydronephrotic lambs (P<.05).

CONCLUSIONS

An obstructive uropathy model was created in female fetal lambs. There were no dysplastic changes in the kidneys in lambs operated on at 90 days' gestation, but there were definite dysplastic changes in those operated on at 60 days. Concentrations of Na and CI in the fetal urine are higher than normal in the 90-day model.

Efficacy of exogenous fibronectin in wound healing in malnourished rats

BACKGROUND/PURPOSE

Fibronectin (FN) plays an important role in fibrin matrix formation during the wound healing process. The authors investigated whether exogenous FN increases the bursting strength (BS) of surgical wounds in malnourished rats.

METHODS

Ninety rats were grouped according to three nutritional conditions (n = 30 in each group). All animals underwent a transverse celiotomy after 3 weeks of feeding, and FN (2 mg/body/day) was given postoperatively to 15 rats in each of the three groups. Wound BS was measured on postoperative days (PODs) 3, 5, and 7 after removal of the sutures.

RESULTS

BS in normally nourished rats (group N; 142.6+/-23.4 mmHg) was significantly higher than that in protein malnourished rats (group PM, 110.2+/-11.2 mm Hg) and protein/ calorie (Cal)-malnourished rats (group PCM, 76.5+/-10.7 mm Hg) on POD 7 (P<.01). However, BS values for groups PM + FN (147.0+/-21.1 mmHg) and PCM + FN (115.1+/-28.9 mm Hg) were intensified significantly in comparison with groups PM and PCM (P<.01). Plasma FN levels in rats of the three FN nontreated groups were similarly decreased on POD 3 or 5, but returned to the preoperative level on POD 7, whereas those for the other three FN-treated groups increased after POD 3.

CONCLUSION

Intravenous administration of FN might strengthen the weakened wounds of malnourished animals.

Non-invasive assessment of language dominance with near-infrared spectroscopic mapping

Hemispheric dominance for language is usually assessed by means of the Wada test where amobarbital is injected into the carotid artery. Recently, positron emission tomography and functional MRI have been used as non-invasive alternatives to this method. We have applied 24-channel near-infrared spectroscopic topography (NIRS) as another non-invasive method to detect the unilateral cerebral activation during a language task. We used 11 healthy volunteers and six patients with intractable epilepsy. A word-generation task was applied for 17 s, followed by an extinction/resting period of 60 s. In healthy volunteers, the inferior frontal region was activated on the side opposite to the subject's handedness in infancy. In the epilepsy cases, the activated side agreed with the dominance determined by the Wada test. Our results demonstrate that NIRS is a feasible non-invasive alternative to the Wada test.

Two cases of torsion of the gallbladder diagnosed preoperatively

BACKGROUND

The authors experienced two cases of torsion of the gallbladder, both of which were correctly diagnosed preoperatively.

METHODS

Two boys, aged 4 and 5 years, were transferred to Yokohama City Seibu Hospital because of their acute abdominal disorders. Diagnostic imaging demonstrated acute inflammatory changes in the gallbladder with an abnormal arrangement of the gallbladder and common bile duct in both cases. Laparotomy findings showed torsion of the gallbladder by 180 degrees and 360 degrees, respectively, at the cystic ducts, resulting in gangrenous change.

RESULTS

Both children recovered uneventfully after cholecystectomy. The diagnostic imaging criteria are (1) collection of fluid between the gallbladder and the gallbladder fossa of the liver, (2) a horizontal rather than vertical arrangement of the long axis of the gallbladder, (3) the presence of a well-enhanced cystic duct located on the right side of the gallbladder, and (4) signs of inflammation including marked edema with thickening of the wall.

CONCLUSIONS

The authors report the clinical characteristics of this uncommon condition, and discuss the significance of accurate preoperative diagnosis of these acute surgical disorders.

Immunologic reaction and genetic factors in biliary atresia

The characteristic histopathological features seen in the livers of patients with biliary atresia (BA) are very similar to those of primary biliary cirrhosis, which is an autoimmune disease. To clarify whether BA liver possess an immunological response similar to that in primary biliary cirrhosis, we studied HLA-DR expression in liver tissue of BA patients, using a HLA-DR staining method, and determined the frequency of HLA types in BA patients and their families. HLA-DR was expressed by the bile duct epithelium in 11 of 16 liver specimens obtained from 13 BA patients. By contrast, HLA-DR was not expressed in liver specimens from 6 patients with congenital biliary dilatation. Among the HLA types seen in BA patients and their families, HLA-A33, -B44 and -DR6 were frequently expressed in blood. These results suggest that certain immunological factors and disease-susceptible genes might be involved in the etiology of BA.

Digestive tract disorders associated with asplenia/polysplenia syndrome

The authors reviewed experience gained over a 20-year period of asplenia or polysplenia syndrome, focusing on patients with associated digestive tract disorders (DTDs). Eleven of 27 patients (40%) with asplenia/polysplenia had associated DTDs. The DTDs comprised malrotation of the intestine in nine, both preduodenal portal vein and gastric volvulus in three, esophageal hiatal hernia in two, and biliary atresia in one. Laparotomy was carried out on four patients with symptoms of acute bowel obstruction and on one patient with biliary atresia. One patient with both malrotation and gastric volvulus, and another with only associated malrotation survived. Nine patients died, eight of cardiac insufficiency and one because of hepatic insufficiency. When infants are diagnosed with heterotaxia, they should be examined for other combined DTDs, because they may have a chance for survival if they undergo surgery when their condition is still stable.

Doppler ultrasonographic evaluation of hepatic circulation in patients following Kasai's operation for biliary atresia

The hepatic circulation of eight children who underwent Kasai's operation for biliary atresia was serially evaluated by Doppler ultrasonography (US). A total of 36 examinations were performed to evaluate the maximal velocities (mvs) of the main portal vein (MPV), splenic vein (SV), and hepatic artery (HA), and to analyze the spectral waveform and the directions of flow. The mean mvs-MPV in four patients for whom adequate biliary diversion had been achieved and whose serum bilirubin had fallen to within the normal range (group A), was 19.8 +/- 7.5 cm/s. Their MPV waveforms were constant, with blood flowing toward the liver, while their mean mvs-SV was 12.1 +/- 5.8 cm/s. In two other patients with apparent hypersplenism, but whose serum bilirubin levels had fallen to nearly normal (group B), the mean mvs-MPV was 20.7 +/- 10.4 cm/s and the mvs-SV was 22.4 +/- 10.4 cm/s. In contrast, the mvs-MPV in the two remaining patients, whose serum bilirubin levels had either not fallen to within the normal range, or had fallen initially but increased due to recurrent cholangitis (group C), was 14.2 +/- 9.1 cm/s. In these patients, the waveforms were unstable, the MPV flows were occasionally hepatofugal, and their mean mvs-SV was 18.0 +/- 5.8 cm/s. The mvs-HA were markedly increased in the latter four patients, whose clinical condition had also deteriorated. These observations led to the conclusion that hepatic circulation evaluated by serial Doppler US provides important information about liver status in children who have undergone Kasai's operation for biliary atresia.

Unilateral pulmonary agenesis with tracheoesophageal fistula: a case report

The authors describe a neonate with unilateral pulmonary agenesis and esophageal atresia (Gross type C). Definitive repair for the atresia was completed during the early neonatal period, and the patient is alive and well more than 1 year after surgery. Most patients with pulmonary agenesis associated with esophageal atresia have not survived, mainly because of postoperative cardiorespiratory failure. Early protection and preservation of respiratory units is essential for the management of these patients.

Concentration measurements of a light absorber localized in a scattering medium

Using a time-resolved technique, we have studied two methods of quantifying the concentration of a light absorber localized in a scattering medium. Because some of the transmitted photons pass through the absorber region many times because of complicated photon propagation in the scattering medium, we used the following methods. First, early-arriving photons passing through the absorber approximately once were selected. Using these photons, we quantified the concentration of the absorber by an ordinary spectroscopic method based on the Beer-Lambert law. Second, for later-arriving photons, after empirically determining the distribution of the number of passes through the absorber as a function of detection time, we obtained the concentration by applying this function to the Beer-Lambert law.

[Variation of the diploid pattern in tissues used as normal controls of solid tumors: advantages and disadvantages of flow cytometric analysis of paraffin-embedded tissues]

The aim of the present work was to study the factors that influence the variation of diploid patterns in 75 areas of histologically normal gastric tissue, located in surgically resected stomachs due to early gastric cancer. Each sample was used as a diploid reference of its respective tumoral area. Fifty five samples were embedded in formalin and 20 corresponded to fresh tissue. It was found that in the older tissues, the cellular debris increased, the localization channel of the peaks shifted to the left (lower than channel 60) and the peak shape was deformed, with an increase in the variation coefficient (around 6) and an elevation and lengthening of phase S. When fresh tissue was used, the first peak was localized around channel 60-70, with a significant reduction of cellular debris, a lower variation coefficient amplitude (2-5) and a phase S adhered to the basal line. Aiming to observe the influence of paraffin embedding over time, 21 tissue samples originally assayed as fresh tissues, were reanalyzed one year later. The same alterations initially observed in old tissues were again noticed. According to these results, it is necessary to select adequate controls for flow cytometric analysis to obtain an adequate histogram interpretation, and specially to calculate the ADN index.

Hemangioma of the upper arm associated with massive hemorrhage in a neonate

A rare case of an ulcerated hemangioma of the upper arm in a neonate is described herein. Resection of the huge hemangioma, which occupied the axilla and extended down the entire length of the upper arm, was necessary due to massive hemorrhage from the ulcer and progressive heart failure caused by the arteriovenous fistula in the hemangioma. After complete resection of the hemangioma, extensive defects of the skin and subcutaneous tissue were replaced by a skin flap closure technique which involved considerable difficulty. However, the arm gradually recovered its size and function with good wound healing. The present case illustrates that rapid surgical intervention may be required to prevent clinical deterioration in such cases.

Optical CT imaging of hemoglobin oxygen-saturation using dual-wavelength time gate technique

Our results may be summarized as follows: 1. In-vivo hemoglobin oxygen-saturation images of rat brain can be obtained using near-infrared light. 2. The transmitted light has multiple scattered components, which degrade spatial resolution, though most of the scattering can be excluded by a suitable time-gating technique. 3. The hemoglobin oxygen-saturation of the cerebellum is higher than that of the cerebrum in untreated anesthetized rats. Although further improvements in the technique should result in better resolution, we have demonstrated the feasibility of using near-infrared light to obtain in-vivo hemoglobin oxygen-saturation images.

An infant with bilateral adrenal neuroblastoma found by mass-screening: report of a case

A male infant with bilateral adrenal neuroblastoma found by mass-screening is herein reported. The patient presented with almost equal-sized tumors, each remaining confined to the respective adrenal gland without crossing the midline. No other tumorous lesion was evident. The two adrenal tumors had similar histologic features and appeared to have grown concurrently. Such simultaneous occurrence of primary adrenal neuroblastoma is unusual, and appears to reflect the multicentric origin of this tumor.

Quad-Detector Arrangement and Sampling Characteristics in Rotary Positron Tomography: POSITOLOGICA II

This paper clarifies that a method of rotary positron-emission computed tomography (PCT) with quad (tri or bi)-detector units can provide the satisfactory sampling characteristics with negligible sacrifice (less than 1 percent) of the detector packing ratio. This paper also presents the array design of quad-BGO (bismuth germanate) units and the sampling characteristics of a rotary PCT system named POSITOLOGICA II. In the rotary PCT, detector units are mounted unequally spaced on a ring so as to provide fine and uniform linear sampling during a 360 degrees rotation of the ring around its center. This principle was applied to a system named POSITOLOGICA I, but it has unidetector units [one detector-one photomultiplier tube (PMT)]. The quad-detector unit consists of four BGO crystals, two PMT's, and a circuit positioning the address of the crystal by which a gamma ray is detected. Merits of the quad units are an effective coupling between rectangular crystals and a photocathode of PMT and reduction of the number of PMT's.