Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

AB0988 CLINICAL FEATURES AND ANALYSIS OF MEFV GENE IN 31 PATIENTS WITH FAMILIAL MEDITERRANEAN FEVER (FMF)

Background:

FMF is recessive systemic autoinflammatory disorder characterized by recurrent fever, peritonitis, pleuritis, pericarditis and arthritis accompanied with headache and abdominal pain. Mutation of MEFV gene encoding pyrin resulted in inflammasome activation and the uncontrolled production of IL-1β. Overview of pathogenesis, clinical features and management in Japanese patients with FMF had been reported. However, the differences of clinical features between mutated and non-mutated of MEFV still remain unclear.

Objectives:

We have analyzed 31 Japanese patients with FMF in Gifu district to clarify the association between various clinical features and mutation ofMEFV.

Methods:

Genomic DNA were purified from white blood cells in 31 FMF patients, and mutated MEFV has been explored. We have analyzedMEFV, TNFRSF1A, MVK and NLRP3 genesin 31 patients with FMF except for 1 patient. Therefore, we excluded another autoinflammatory diseases such as TNF receptor-associated syndrome (TRAPS), mevalonate kinase deficiency and cryopyrin-associated periodic syndrome. Clinical symptoms and laboratory data were analyzed around onset time. Each patient had been treated with colchicine (0.5-2 mg).

Results:

Characteristics of Patients with FMF (22 female/9 male) were as follows; Onset time were 0-56 years-old (21.4 ±11.8), and Frequencies of clinical symptoms such as periodic fever, headache, abdominal pain, arthralgia, chest pain, cervical lymph nodes swelling, and myalgia were 31/31, 9/31, 8/31, 6/31, 5/31, 3/31 and 1/31, respectively (double symptoms were observed). Patients with FMF were divided into 3 groups as follows; Patients with typical compound heterozygous mutations of MEFV (E148Q /M694I) which indicated exon 10 mutation, were 5 cases (G1). Patients with atypical mutations, except for exon 10, such as 133G>A in 3UTR, exon 1 (E84K), 2 (L110P, E148Q), 3(R202Q, P257L, G304R, P369S, R408Q), 5(S503C) and 9(I591M) were 13 cases (G2). Patients with no mutations in MEFV gene were 12 cases (G3). There were no significant differences of age at first visiting hospital (FV)and onset age of fever attack (O) (FV: 29.0 ± 15.6, 27.1 ± 12.5 years-old (yo) and 34.7 ± 12.7 yo, O: 21.0 ± 17.6 yo, 17.8 ± 12.1 yo and 25.2 ± 6.5). But significant differences in duration of fever attack (D) and frequency of fever attack (FF) between G1 and G2 or G3 were observed as follows; (D: 2.2 ± 0.4 days vs 5.5 ± 3.1 days, P<0.05, and 3.8 ± 1.7 days), FF: 0.72 ± 0.3/month (M), 1.24 ± 1.1/M, and 1.5 ± 0.7/M vs group1, P<0.05), respectively. Laboratory examinations such as WBC, CRP and serum amyloid A (SAA)at fever attack were not significantly different between 3 groups. All of those patients were effective for colchicine treatment except for 2 patients in group 1 because of loss of hair, severe diarrhea and liver dysfunction due to side effects of colchicine. Finally, 4 patients in G1and G2 received canakinumab treatment. Patients withMEFVmutations have no family histories. Mutations of E148Q were found in 12 patients (40%).

Conclusion:

We have examined association between clinical features and mutations of MEFV in 31 patients in Gifu district, suggesting that duration of fever attacks and frequency of fever attacks in G1 are significantly shorter than G2 and G3, respectively in Japanese patients with FMF. Mutations of E148Q in exon 2 were observed in 16-23 % of normal Japanese patients, indicating that E148Q is the polymorphism or accelerating factor.

Disclosure of Interests:

None declared

Trajectories of endoscopic Barrett esophagus: Chronological changes in a community-based cohort

AIM

To elucidate longitudinal changes of an endoscopic Barrett esophagus (BE), especially of short segment endoscopic BE (SSBE).

METHODS

This study comprised 779 patients who underwent two or more endoscopies between January 2009 and December 2015. The intervals between the first and the last endoscopy were at least 6 mo. The diagnosis of endoscopic BE was based on the criteria proposed by the Japan Esophageal Society and was classified as long segment (LSBE) and SSBE, the latter being further divided into partial and circumferential types. The potential background factors that were deemed to affect BE change included age, gender, antacid therapy use, gastroesophageal reflux disease-suggested symptoms, esophagitis, and hiatus hernia. Time trends of a new appearance and complete regression were investigated by Kaplan-Meier curves. The factors that may affect appearance and complete regression were investigated by χ² and Student-t tests, and multivariable Cox regression analysis.

RESULTS

Incidences of SSBE and LSBE were respectively 21.7% and 0%, with a mean age of 68 years. Complete regression of SSBE was observed in 61.5% of initial SSBE patients, while 12.1% of initially disease free patients experienced an appearance of SSBE. Complete regressions and appearances of BE occurred constantly over time, accounting for 80% and 17% of 5-year cumulative rates. No LSBE development from SSBE was observed. A hiatus hernia was the only significant factor that facilitated BE development (P = 0.03) or hampered (P = 0.007) BE regression.

CONCLUSION

Both appearances and complete regressions of SSBE occurred over time. A hiatus hernia was the only significant factor affecting the BE story.

A substantial incidence of silent short segment endoscopically suspected esophageal metaplasia in an adult Japanese primary care practice

AIM: To determine the incidence and characteristics of endoscopically suspected esophageal metaplasia (ESEM) in a primary adult care institution.

METHODS: Eight hundred and thirty two consecutive individuals (mean age, 67.6 years) undergoing upper gastrointestinal endoscopy between January 2009 and December 2010 were included in this study. The diagnosis of ESEM was based on the criteria proposed by the Japan Esophageal Society, and was classified as long segment ESEM (3 cm or more) or short segment ESEM (< 3cm). Short segment ESEM was further divided into circumferential and partial types. Age, gender, hiatus hernia, esophagitis, gastroesophageal reflux disease (GERD)-suggested symptoms, and antacid medications were recorded as background factors. Esophagitis was graded according to the Los Angeles classification. Hiatus hernia was divided into absent and at least partially present.

RESULTS: Long and short segment ESEM were found in 0 and 184 (22.1%) patients, respectively (mean age of short segment ESEM patients, 68.3 years). Male gender and hiatus hernia were shown to be significant factors affecting short segment ESEM by both univariate (P = 0.03 and P = 9.9x10^-18) and multivariate [Odds ratio (OR) = 1.45; P = 0.04, and OR = 43.3; P = 1.5x10^-7)] analyses. Two thirds of patients with short segment ESEM did not have GERD-suggested symptoms. There was no correlation between short segment ESEM and GERD-suggested symptoms.

CONCLUSION: The incidence of short segment ESEM in our community practice seems higher than assumed in Asian countries. As GERD-suggested symptoms are a poor predictor of ESEM, endoscopists should bear in mind that silent short segment ESEM does exist and, in fact, was found in the majority of our patients.

Analysis of T cell receptor Vbeta diversity in peripheral CD4 and CD8 T lymphocytes in patients with autoimmune thyroid diseases

Autoimmune thyroid diseases are characterized by intrathyroidal infiltration of CD4(+) and CD8(+) T lymphocytes reactive to self-thyroid antigens. Early studies analysing T cell receptor (TCR) Valpha gene usage have shown oligoclonal expansion of intrathyroidal T lymphocytes but not peripheral blood T cells. However, TCR Vbeta diversity of the isolated CD4(+) and CD8(+) T cell compartments in the peripheral blood has not been characterized fully in these patients. We performed complementarity-determining region 3 (CDR3) spectratyping as well as flow cytometric analysis for the TCR Vbeta repertoire in peripheral CD4(+) and CD8(+) T cells from 13 patients with Graves' disease and 17 patients with Hashimoto's thyroiditis. Polyclonal TCR Vbeta repertoire was demonstrated by flow cytometry in both diseases. In contrast, CDR3 spectratyping showed significantly higher skewing of TCR Vbeta in peripheral CD8(+) T cells but not CD4(+) T cells among patients with Hashimoto's thyroiditis compared with healthy adults. We found trends towards a more skewed CDR3 size distribution in those patients having disease longer than 5 years and requiring thyroid hormone replacement. Patients with Graves' disease exhibited no skewing both in CD4(+) and CD8(+) T cells. These findings indicate that clonal expansion of CD8(+) T cells in Hashimoto's thyroiditis can be detected in peripheral blood and may support the role of CD8(+) T cells in cell-mediated autoimmune attacks on the thyroid gland in Hashimoto's thyroiditis.

Clonotypic analysis of T cell reconstitution after haematopoietic stem cell transplantation (HSCT) in patients with severe combined immunodeficiency

Haematopoietic stem cell transplantation (HSCT) is performed for treatment of a broad spectrum of illnesses. Reconstitution of an intact immune system is crucial after transplantation to avoid infectious complications, and above all, the establishment of T cell receptor (TCR) diversity is the most important goal in the procedure. Until recently, little has been known of the mechanism of T cell reconstitution in the very early period after HSCT. In this study, we analysed TCR repertoires sequentially in four patients with severe combined immunodeficiency (SCID) before and after HSCT. In all patients, the TCR repertoires were extremely abnormal before HSCT, whereas after transplantation there was progressive improvement in TCR diversity, based on analysis of the TCR Vbeta repertoire and CDR3 size distributions. Somewhat unexpectedly, there was a significant but transient expansion of TCR diversity 1 month after transplantation in all cases. Clonotypic analysis of TCRs performed in one case showed that many T cell clones shared identical CDR3 sequences at 1 month and that the shared fraction decreased progressively. These results indicate that early expansion of TCR diversity may reflect transient expansion of pre-existing mature T cells from the donor blood, independent of de novo T cell maturation through the thymus.

Selective expansion of CD16highCCR2- subpopulation of circulating monocytes with preferential production of haem oxygenase (HO)-1 in response to acute inflammation

Monocytes are composed of two distinct subpopulations in the peripheral blood as determined by their surface antigen expressions, profiles of cytokine production and functional roles played in vivo. We attempted to delineate the unique functional roles played by a minor CD16(high)CCR2(-) subpopulation of circulating monocytes. They produced significant levels of interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha, but very low levels of IL-10 upon in vitro stimulation. Characteristic profiles of cytokine production were confirmed by stimulating purified subpopulations of monocytes after cell sorting. It was noteworthy that freshly isolated CD16(high)CCR2(-) monocyte subpopulations produced significant levels of haem oxygenase (HO)-1, whereas the major CD16(low)CCR2(+) subpopulation produced little. These results were contrary to the generally accepted notion that the CD16(high)CCR2(-) monocyte subpopulation plays a predominantly proinflammatory role in vivo. The CD16(high)CCR2(-) subpopulation increased in Kawasaki disease and influenza virus infection. In accord with this, HO-1 mRNA expression by mononuclear cells was significantly increased in these illnesses. These results indicate that CD16(high)CCR2(-) subpopulations are of a distinct lineage from CD16(low)CCR2(+) monocytes. More importantly, they may represent a monocyte subpopulation with a unique functional role to regulate inflammation by producing HO-1 in steady state in vivo.

Oligoclonal expansion of circulating and tissue-infiltrating CD8+ T cells with killer/effector phenotypes in juvenile dermatomyositis syndrome

Although triggering by infectious agents and abnormal immune responses may play some role in the pathogenesis of juvenile dermatomyositis syndrome (JDMS), the precise mechanism of muscle destruction and vascular damage is largely unknown. In this study, we tried to elucidate the role of cytotoxic T cells in two patients with JDMS, who were diagnosed based on the characteristic symptoms, laboratory data, MRI findings and electromyographic patterns. Peripheral blood T cell phenotypes were determined by flow cytometry, using mAbs against specific T cell receptor (TCR) Vbetas. Complementarity-determining region3 (CDR3) size analysis was performed by gene scanning of CDR3 polymerase chain reaction (PCR) amplification products specific for each Vbeta. Subsequently, CDR3 nucleotide sequences were obtained after cloning of the predominant products. The distribution of lymphocytes infiltrating the muscle tissue was analysed by immunohistochemistry. In both patients examined, a unique combination of TCR Vbeta repertoires was increased within the CD8+ T cells. These subpopulations expressed a characteristic phenotype, indicating that they are memory/effector T cells with killer functions. At the same time, immunohistological and molecular biological examinations of the biopsied muscle samples revealed that identical CD8+ T cell clones with identical phenotypes/TCR Vbeta infiltrated within the inflammatory tissue, in particular around vessels. These findings indicate that oligoclonal expansion of CD8+ T cells plays a central role in the pathogenesis of muscle injury in the juvenile form of dermatomyositis syndrome and may provide a useful clinical parameter of disease activity and responsiveness to anti-inflammatory therapy.

Gastric cancer with metastasis to the gingiva

The present case report describes a gastric cancer which showed unusual metastasis in the oral region. A 56-year-old male patient underwent total gastrectomy and splenectomy due to advanced gastric cancer in the upper third of the stomach. Fifteen months later, he presented with anorexia and gingival swelling of durations of approximately 3 and 1 month, respectively. The gastric tumor was histologically a signet ring cell and a poorly differentiated cancer with a moderate degree of vascular invasion. Biopsy specimens from the gingival tumor revealed a signet ring cell cancer. Other metastatic sites were the brain, limb bones and abdominal lymph nodes. A bone scintigram revealed an abnormal uptake in the limb bones, while it did not exhibit any abnormality in the oral region. Correlation between the histology of the gingival tumor with that of the gastric cancer, as well as the absence of a gingival tumor at the time of prior gastrectomy, led to a diagnosis that the gingival tumor was a metastasis from gastric cancer. Gastric cancer metastasizing to the oral region, either the osseus or the oral soft tissue, is very rare. Although it cannot be proved without an autopsy, negative findings in the mandible by bone scanning in the present case suggest that direct gingival metastasis can be considered, rather than mandibular metastasis involving the gingiva. Hematogenous spread could be a mechanism of metastasis for this unusual tumor.

Two cases of supernumerary ovary: one with large fibroma with Meig's syndrome and the other with endometriosis and cystic change

Reports of supernumerary ovaries are rare. We describe two such cases, one with fibroma and the other with endometriosis and cystic change. A large fibroma measuring 17.4 x 12.0 x 7.5 cm in size was found in the supernumerary ovary of the omentum in the first case of a 47-year-old married woman with Meig's syndrome. The second case was associated with endometriosis and cystic change, measuring 11 x 5 x 3 cm in size and located in the upper abdominal cavity. It was attached to the uterus of a 28-year-old pregnant woman who had neither fibroma nor Meig's syndrome. Histologically, corpus albicans and a few primordial germ cells were demonstrated, respectively. A fibroma showing a storiform pattern was found in the first case. The second case had endometriosis and a thin-walled cyst with bleeding and necrosis caused by torsion. Immunohistochemically, desmin, alpha-smooth muscle actin, c-kit, CA125, Na+/K+ATPase, overexpression of p53, myc and ras were all negative in the fibroma cells of the first case, and in the endometriosis and cyst wall of the second case. The fibroma cells were positive for vimentin and estrogen receptor, and the proliferating cell nuclear antigen was sporadically demonstrated in their nuclei. The mutation of the p53 gene at exons 5-8 was not detected by sequence analysis. Using RT-PCR, bax, bcl-2 and p16 were not detected either. Clinically, the two cases presented here did not show abnormal hormonal symptoms. They were diagnosed as abdominal tumors or masses. Based on these considerations, one might assume that supernumerary ovaries are probably more frequent than reported at present.

Cytoprotective role of heme oxygenase (HO)-1 in human kidney with various renal diseases

BACKGROUND

We previously reported that glomerular changes in the renal specimen of a human case with heme oxygenase-1 (HO-1) deficiency were mild, but tubulointerstitial injury advanced progressively. This study examined the patterns of HO-1 production in the kidney in various renal diseases. Furthermore, the critical cytoprotective roles of HO-1 were evaluated in the kidney by comparing HO-1 production and expressions of carboxymethyllysine (CML) and pentosidine, both of which are markers of oxidative stress.

METHODS

Renal biopsy or autopsy materials were obtained from a total of 74 patients. Degrees of hematuria and proteinuria and the levels of urinary N-acetyl-beta-D-glucosaminidase (NAG), beta2-microglobulin (beta2m), and creatinine were evaluated. Immunohistochemical studies for HO-1, CML, and pentosidine expressions were performed with their specific antiserum.

RESULTS

HO-1 staining was observed within tubular epithelial cells in all of the renal diseases, but was not detected within intrinsic glomerular cells. HO-1 staining tended to be more intense within distal tubuli than in proximal tubuli. Within distal tubuli, there was no significant correlation between intensity of HO-1 staining and degree of hematuria or presence of proteinuria. Within proximal tubuli, HO-1 staining tended to be more intense with greater degrees of hematuria, presence of proteinuria, and moderate tubulointerstitial damage. Intense staining of CML and pentosidine was observed within renal tubular epithelial cells only in HO-1-deficient patients.

CONCLUSIONS

HO-1 plays important roles in protecting renal tubuli from oxidative injuries, as these cells are constantly exposed to various oxidative stresses. It is suggested that renal tubular epithelia are more susceptible to oxidative stress due to the lack of this critical enzyme in HO-1 deficiency.

Possibility of false-positive detection for sporozoites in mosquitos (Diptera: Culicidae) by nested polymerase chain reaction using Plasmodium yoelii genomic DNA

Anopheles stephensi Liston and An. saperoi Bohart and Ingram infected with the rodent malaria parasite Plasmodium yoelii nigeriense. They were examined 12 and 19 days after blood feeding for sporozoites in head with anterior thorax (HT) and oocysts in abdomen with posterior thorax (AB) by light microscopy and by the nested polymerase chain reaction (nested PCR-based on the amplification of the sequences of the small subunit ribosomal RNA gene). The detection rate of parasite DNA by nested PCR in HT samples 12 days after blood feeding was similar to that by microscopic method. However, in HT samples 19 days after blood feeding, the rate by the PCR method was higher than that by the microscopic method. The incidence of sporozoites in salivary glands of infected mosquitos for 12 days after blood sucking was examined by the PCR method. Parasite DNA in HT of Aedes albopictus Skuse (a non vector for the rodent malaria) as well as An. stephensi and An. saperoi was detected for up to 4 days after feeding on mouse with the rodent malaria parasites. The results indicate that when the PCR method is used for detection of sporozoites of human malaria in mosquitos collected in the field, there are possibilities of including false-positive data for mosquitos that have just or recently fed on human blood infected with malaria (erythrocytic form).

The relationship between anthropometric indicators of nutritional status and malaria infection among youths in Khammouane Province, Lao PDR

We assessed anthropometric indicators of the nutritional status among children and adolescents in Khammouane Province in the Lao PDR and examined the relation between malnutrition and malaria infection. The survey was conducted from July to August 1999 using a sample of 309 youths aged 2 to 18 years. Malnutrition was categorized as stunting (below -2 Z scores height-for-age) and wasting (below -2 Z scores weight-for-height). The prevalence of stunting and wasting were 45.1% and 9.2%, respectively, which were classified by WHO as "very high" prevalence. Compared with the results of previous national surveys in Lao PDR, similar prevalence was shown. The prevalence of wasting in youths with P. falciparum infection was 17%, significantly higher than those of not infected (4%). On the other hand, P. vivax infection was not associated with any indicators of malnutrition. In conclusion, this study showed that the nutritional status in youths was poor and P. falciparum infection was associated with acute malnutrition.

Aedes (Finlaya) japonicus (Diptera: Culicidae), a newly recognized mosquito in the United States: analyses of genetic variation in the United States and putative source populations

Introduction of potential disease vectors into a new geographic area poses health risks to local human, livestock, and wildlife populations. It is therefore important to gain understanding of the dynamics of these invasions, in particular its sources, modes of spread after the introduction, and vectorial potential. We studied the population genetics of Aedes (Finlaya) japonicus japonicus (Theobald), an Asian mosquito that was recognized for the first time in the United States in 1998. We examined patterns of genetic diversity using random amplified polymorphic DNA and sequences of ND4 of mtDNA by comparing samples from populations spanning the range of this mosquito in Japan (six samples) and the United States (nine samples) as well as specimens intercepted in New Zealand in 1999. We found geographically differentiated populations in Japan, indicating limited gene flow even on small spatial scales. In the United States, we found evidence of significant genetic differentiation between samples from New York, Connecticut, and New Jersey and those from mid-Pennsylvania and Maryland. We were unable to pinpoint the source location(s) in Japan, although some of the U.S. samples are genetically close to samples from south Honshu and western Kyushu. Further studies should include samples from Korean populations. Distinct genetic signatures in U.S. populations undergoing expansion suggest the possibility of local increases in genetic diversity if and where they meet.

Clearance of antiphospholipid antibodies in pregnancies treated with heparin

OBJECTIVE

To describe the natural history of serum antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies) in pregnant women treated with heparin, and to identify a possible association between changes in antibody status and outcomes of subsequent pregnancies.

METHODS

Thirty-six women with antiphospholipid antibodies who had three or more repeated miscarriages were enrolled. Intravenous heparin was used for each of the first pregnancies after referral. Changes in antibody status were investigated with relation to outcomes of the index and subsequent pregnancies.

RESULTS

Eighteen of 23 pregnancies in 36 antibody-positive women treated with heparin resulted in term or preterm deliveries with live-born infants, and five ended in abortions. Antibodies cleared in ten of 12 term pregnancies, in five of six preterm pregnancies, and in one of five abortions. There was a statistically significant difference between the term pregnancy and abortion groups (P <.05). Eleven second and third pregnancies in nine women in whom antibodies cleared resulted in term or preterm deliveries of live-born infants, without heparin therapy. The second and third pregnancies in one woman whose antibodies persisted ended in miscarriages despite repeated heparin administration.

CONCLUSION

Antiphospholipid antibodies cleared spontaneously in some pregnant women treated with heparin. Subsequent pregnancies among women in whom antibodies cleared were managed successfully without medication, whereas pregnancies in women with persistent antibodies required treatment.

In situ observation of photoinduced refractive-index changes in filaments formed in glasses by femtosecond laser pulses

We investigated the relationship between the formation of filaments and local refractive-index changes induced by femtosecond laser pulses in silica glass. In situ observation revealed that the location of a filament coincided with that of the refractive-index change. Observation also showed that the region of refractive-index change was elongated toward the upstream direction of the laser pulses with increasing exposure time. The region of refractive-index change was several hundred micrometers long, and its diameter was smaller than 2 mum. The refractive-index change was confirmed by two of three different methods to be as large as 0.8 x 10(-2).

Optical seizing and merging of voids in silica glass with infrared femtosecond laser pulses

We demonstrate that one can seize and translate voids formed by IR femtosecond laser pulses inside silica glass and can also cause two voids to merge into one. We also present clear evidence of a void and its surrounding region by showing scanning electron microscope images of cleaved voids, which we produced by cleaving through the glass along a plane that included a thin laser-ablated line on the surface of the glass and the voids formed inside.

Structural evidence of genomic exon-deletion mediated by Alu-Alu recombination in a human case with heme oxygenase-1 deficiency

We previously reported a family affected by heme oxygenase-1 (HO-1) deficiency [Yachie et al., 1999]. The proband was a compound heterozygote for a complete loss of exon 2 (the maternal allele) and a two-nucleotide deletion within exon 3 (the paternal allele). In this report, we describe a large genomic deletion (1730 bp) including entire exon 2 in this family as a specific mechanism generating exon-2 absence observed in the HO-1 mRNA. Analysis of the deletion junction demonstrated fusion of a 5' portion of Alu-Sx element with a 3' portion of Alu-Sq element. The junction contained sequences with high homology to the recombinogenic Alu "core" sequence. These structural features of the HO-1 gene suggest homologous recombination associated with Alu element. This study presents the initial characterization of the HO-1 gene defect causing a human case of HO-1 deficiency and provides the molecular basis for understanding this genetic disease.

Identification of Culex vishnui subgroup (Diptera: Culicidae) mosquitoes from the Ryukyu Archipelago, Japan: development of a species-diagnostic polymerase chain reaction assay based on sequence variation in ribosomal DNA spacers

The Culex vishnui subgroup includes three important vectors of Japanese encephalitis virus, Culex tritaeniorhynchus Giles, Cx. pseudovishnui Colless, and Cx. vishnui Theobald, all of which occur in the Ryukyu Archipelago, Japan. Although these three species have been shown to be vectors of JE virus in many areas of Southeast Asia, it is not yet known what role each plays in the transmission of the virus in this region. Reliable identification of adult, field-collected specimens is a critical component in epidemiological studies of virus transmission. Mosquitoes in the Cx. vishnui subgroup can be reliably identified in the larval stage. However, because females of these species are very similar, it is difficult to distinguish among them using morphology. We developed a polymerase chain reaction (PCR) assay for the identification of these species. Three species-specific primers were developed for the PCR assay based on a comparative analysis of the nucleotide sequence of the first internal transcribed spacer (ITS1) in the ribosomal DNA gene array. The primers, CT2REV, CP1REV, and CV1REV were designed to amplify a single DNA fragment each from Cx. tritaeniorhynchus, Cx. pseudovishnui, and Cx. vishnui, respectively, when paired with a single forward primer that is complementary to the highly conserved 18S rDNA gene. The amplified fragments were separated easily and identified on an agarose gel to facilitate species identification.

Tubular injury as a cardinal pathologic feature in human heme oxygenase-1 deficiency

Heme oxygenase (HO) catalyzes degradation of heme to biliverdin, iron, and carbon monoxide. It consists of three isoforms: an inducible form (HO-1), a constitutive form (HO-2), and the third isoform (HO-3), with properties similar to HO-2. There is limited evidence to suggest that the induction of HO-1 may have anti-inflammatory effects in an in vivo model of oxidative stress-mediated renal injury. We experienced the first human case of HO-1 deficiency. The patient had persistent proteinuria and hematuria, with biochemical evidence of renal tubular injury. We obtained three consecutive renal specimens: two from renal biopsies at 2 and 5 years of age and the third from autopsy at 6 years of age. The patient had systemic vascular endothelial-cell injury with massive intravascular hemolysis. The serum was loaded with heme and a large amount of heme-conjugated haptoglobin. A high concentration of haptoglobin was also detectable in urine. Mesangial proliferation or change in glomerular capillary-wall thickness was relatively mild to moderate in all specimens. Electron microscopic examination showed widespread endothelial detachment and subendothelial deposits of an unidentifiable material. It was striking that tubulointerstitial injury, with tubular dilatation and/or atrophy, interstitial fibrosis, and inflammatory cell infiltration, advanced progressively. Tubular epithelial cells were injured, and massive deposition of iron and haptoglobin was detectable. Bowman's capsules were dilated significantly, probably secondary to the collapse of atrophic tubuli. This is the first report to show that HO-1 has critical roles in vivo in protecting renal tubuli, in addition to vascular endothelium, from oxidative injury.

Age-dependent increase of IgE-binding and FcepsilonRI expression on circulating basophils in children

Peripheral blood basophils are sparse in the circulation, but they express high-affinity receptors for IgE (FCepsilonRI) and bind IgE efficiently. The present study was performed to elucidate the role of IgE bound on the basophil surface in the development of allergic responses during infancy and early childhood. IgE-binding and FcepsilonRI expression on basophils were evaluated by two-color flow cytometry. Basophil-bound IgE increased rapidly and reached adult levels during infancy in atopic patients, while it gradually increased with advancing age in parallel with serum IgE in normal controls. IgE-binding and FcepsilonRI expression in atopic children were higher than in normal controls among various age groups. They correlated with serum IgE levels but reached a plateau when serum IgE exceeded 300 ng/mL. A low, but significant level of FcepsilonRI expression was observed on cord blood basophils, although IgE-binding was usually undetectable. Incubation of cord blood with IgE rapidly saturated the preexisting IgE receptors and basophil-bound IgE levels increased. When neonatal basophils were cultured for 48 h with IgE, FcepsilonRI expression was upregulated dose-dependently and IgE-binding increased further. The up-regulation of FcepsilonRI was completely inhibited by cycloheximide, indicating that it was dependent on de novo protein synthesis. These results suggest that IgE-binding on basophils serves as a sensitive indicator of allergic sensitization, and that IgE functions as a positive regulator of FcepsilonRI expression in vivo.

Mark-release-recapture experiment with adult Anopheles minimus (Diptera: Culicidae) on Ishigaki Island, Ryukyu Archipelago, Japan

Movement of adult An. minimus Theobald between larval habitats and feeding sites was investigated by mark-release-recapture in March 1993 on Ishigaki Island, Ryukyu Archipelago, Japan. Unfed (998 females) and fed (1,485 females) cohorts from a laboratory colony were marked with different colors of fluorescent dye, and released near Nishihama stream where larvae were abundant. Overall, 42 fed (2.82%) and 13 unfed (1.30%) females were recaptured. Among these, 12 females were recaptured at a cowshed, the nearest blood meal source. Most females in the fed cohort recaptured at the release point had developing or matured ovaries, whereas 55% at the cowshed were parous. The movement of released females from larval habitat to the cowshed for blood feeding indicated a flight distance > 1 km.

Culex (Acallyntrum) miyagii (Diptera: Culicidae): new species from Seram Island, Indonesia, with keys to the species of the subgenus

Culex (Acallyntrum) miyagii is described as a new species from Seram Island, Indonesia. The adult male, female, pupa, and larva are described in detail, and illustrations of the male genitalia, pupa, and larva are provided. Cx. miyagii is a forest species breeding in inflorescences of Costus sp. (Costaceae). Keys are provided for identifying the females and 4th-instar larvae of the species of Acallyntrum.

Oxidative stress causes enhanced endothelial cell injury in human heme oxygenase-1 deficiency

The first known human case of heme oxygenase-1 (HO-1) deficiency is presented in this report. The patient is a six-year-old boy with severe growth retardation. He has been suffering from persistent hemolytic anemia characterized by marked erythrocyte fragmentation and intravascular hemolysis, with paradoxical increase of serum haptoglobin and low bilirubin. An abnormal coagulation/fibrinolysis system, associated with elevated thrombomodulin and von Willebrand factor, indicated the presence of severe, persistent endothelial damage. Electron microscopy of renal glomeruli revealed detachment of endothelium, with subendothelial deposition of an unidentified material. Iron deposition was noted in renal and hepatic tissue. Immunohistochemistry of hepatic tissue and immunoblotting of a cadmium-stimulated Epstein-Barr virus-transformed lymphoblastoid cell line (LCL) revealed complete absence of HO-1 production. An LCL derived from the patient was extremely sensitive to hemin-induced cell injury. Sequence analysis of the patient's HO-1 gene revealed complete loss of exon-2 of the maternal allele and a two-nucleotide deletion within exon3 of the paternal allele. Growth retardation, anemia, iron deposition, and vulnerability to stressful injury are all characteristics observed in recently described HO-1 targeted mice. This study presents not only the first human case of HO-1 deficiency but may also provide clues to the key roles played by this important enzyme in vivo.

Fabricating micro-Bragg reflectors in 3-D photorefractive waveguides

Bragg reflectors as small as optical waveguides can be used at the intersections of waveguides as spectral filters, beam splitters, or beam combiners. We present the concept of fabricating small Bragg reflectors in photorefractive waveguides and show the spectral selectivity of these micro-Bragg reflectors fabricated in a lithium niobate crystal. We also show that we can fabricate waveguide structures simultaneously with the micro-Bragg reflector, by using a crystal whose c-axis is directed 45 degree off the optical axis of the fabrication beam. The reflectivity of the micro-Bragg reflector was smaller than 0.01 and was not large enough for the immediate use.

Breeding habitats of Aedes aegypti (L) and Aedes. albopictus (Skuse) in villages of Barru, South Sulawesi, Indonesia

The breeding habitats of the dengue vector, Aedes aegypti and Aedes albopictus, were studied using larval collection method inside and outside houses in 6 villages of Barru, South Sulawesi, Indonesia from July 1994 to August 1995. Aedes aegypti was the dominant species, being abundant indoors especially in the coastal areas. Aedes albopictus was breeding primarily in outdoor containers in the hill and mountain areas. Earthen jar was the most common breeding habitat of Aedes aegypti in all villages surveyed. Drum can was the most common outdoor breeding habitat of Aedes albopictus in the hill and mountain areas. The high Breteau indices of Aedes aegypti and Aedes albopictus suggests that these species may play an important role in the transmission of dengue hemorrhagic fever in Barru where epidemics of the fever occur occasionally.

Description of Topomyia irianensis n. sp. and new records of To. papuensis from Maluku and Irian Jaya, Indonesia (Diptera:Culicidae)

The adults, male genitalia, pupa, and larva of Topomyia (Topomyia) irianensis n. sp. from Irian Jaya, Indonesia, are described and illustrated. The new species is compared to closely related species, Topomyia dejesusi Baisas and Feliciano, 1953, and Topomyia argyropalpis Leicester, 1908. Topomyia (Suaymyia) papuensis Marks was recorded for the first time from Maluku and Irian Jaya. This is the first record of the genus Topomyia from Maluku and Irian Jaya, Indonesia.

[Survey of allergic diseases in 3-year old children in Okinawa City]

A questionnaire survey was conducted between September 1993 and March 1994 to ascertain the presence of allergic diseases among 3-year old children in Okinawa City of Okinawa Prefecture. Nine hundred and twenty-two questionnaires were sent to caretakers of 3-year old children, with 697 responses of which five invalid cases were deleted for a total of 692 responses which were analyzed. About 30% of these children had allergic diseases as diagnosed by the medical doctor. Among the respondents 15.1% had experience of atopic dermatitis, while 13.9% had experience of asthma. The incidence of atopic dermatitis in this survey was lower than those reported in other prefectures of Japan. Symptoms for atopic dermatitis were more severe during summer. About 15% of the children had been on a diet regimen for prevention or treatment of allergic diseases since the time of conception. Eighteen percent of the respondents used a vacuum cleaner on their bedding. A high proportion of respondents (65.9%) obtained information from newspapers or magazines about allergic diseases.

Historical review of mosquito control as a component of malaria eradication program in the Ryukyu Archipelago

In the Ryukyu Archipelago, where malaria used to be endemic, eradication of the disease was achieved by the year 1962, as a consequential effect of a planned malaria eradication program in the area. This achievement was facilitated by concerted efforts in controlling vector mosquitos and treatment of all detected and presumptive cases of malaria infections. Anopheles minimus Theobald and An. sinensis Wiedemann were common in all areas endemic for malaria. Knowledge of the biology and bionomics of the mosquitos in malaria endemic areas formed the basis for formulating strategies for the control of vectors and subsequent surveillance activities. Insecticide residual spray, larvivorous fishes and environmental management were the basic strategies for vector control. The whole program was augmented by an active community participation in all eradication activities.

Diurnal changes in leaf gas exchange characteristics in the uppermost canopy of a rain forest tree, Dryobalanops aromatica Gaertn. f

Dryobalanops aromatica Gaertn. f. is a major tropical canopy species in lowland tropical rain forests in Peninsular Malaysia. Diurnal changes in net photosynthetic rate (A) and stomatal conductance to water vapor (g(s)) were measured in fully expanded young and old leaves in the uppermost canopy (35 m above ground). Maximum A was 12 and 10 micro mol m(-2) s(-1) in young and old leaves, respectively; however, because of large variation in A among leaves, mean maximum A in young and old leaves was only 6.6 and 5.5 micro mol m(-2) s(-1), respectively. Both g(s) and A declined in young leaves when T(leaf) exceeded 34 degrees C and leaf-to-air vapor pressure deficit (DeltaW) exceeded 0.025, whereas in old leaves, g(s) and A did not start to decline until T(leaf) and DeltaW exceeded 36 degrees C and 0.035, respectively. Under saturating light conditions, A was linearly related to g(s). The coefficient of variation (CV) for the difference between the CO(2) concentrations of ambient air and the leaf intercellular air space (C(a) - C(i)) was smaller than the CV for A or g(s), suggesting that maximum g(s) was mainly controlled by mesophyll assimilation (A/C(i)). Minimum C(i)/C(a) ratios were relatively high (0.72-0.73), indicating a small drought-induced stomatal limitation to A and non-conservative water use in the uppermost canopy leaves.

[Assessment by flow cytometric method of IgE-binding state of basophils in allergic disorders]

Basophils, as well as mast cells, express Fc epsilon RI on the surface. It is known that activation of basophils and mast cells leads to induction of chronic allergic inflammation. In this study, levels of IgE bound to the surface of peripheral blood basophils were measured using a flowcytometry, and their clinical relevance was evaluated. Peripheral whole blood samples were stained with FITC-conjugated anti-IgE. The fluorescence intensity of the FITC-positive cells within mononuclear cell region was determined. Basophil-bound IgE levels increased along with age and reached invariably high levels of adults. The levels of basophil-bound IgE were higher among allergics than normal controls, in early infancy. In addition, many of the infants with repeated wheezing episodes also exhibited high levels of it. These findings suggest that early exposure of predisposed infants to antigens leads to early sensitization of circulating basophils. Basophil-bound IgE levels correlated well with serum IgE concentration, but they remained constant when IgE concentrations exceeded 300 ng/ml, suggesting that IgE-binding capacity of basophils become saturated at this IgE level. In conclusion, it is shown that flowcytometric measurement of basophil-bound IgE provides a useful method of analyzing this rare cell population within the peripheral circulation, and it serves as a critical parameter to evaluate the allergic inflammation in vivo.

Occurrence of Aedes (Stegomyia) spp. mosquitoes (Diptera: Culicidae) in Halmahela villages, Indonesia

Aedes (Stegomyia) spp. mosquitoes breeding in containers in and around human houses were surveyed in Halmahela villages, the North Moluccas, Indonesia. Adults reared from larvae found in containers and those reared from eggs collected by ovitraps revealed the dominance of Aedes scutellaris (Walker) in residential areas. Breeding of Aedes aegypti (L.) and Aedes albopictus (Skuse) was confirmed in a few coastal villages with high human densities.

Age structure of Anopheles subpictus (Diptera:Culicidae) collected by a light trap in Halmahela, Indonesia

Age structure of Anopheles subpictus Grassi was studied at a Halmahela village, Indonesia. Ovary development of females reared with 2% sugar solution after emergence ceased at Stage I and their ovary size remained small (mean length x width = 0.68 x 0.18 mm). Females with such small ovaries occupied 21.2% of unfed Stage I females in cattle-bait samples. The remaining unfed Stage I or II females had cleary larger ovaries (mean 1.17 x 0.39 mm). Unfed Stage I or II females collected by the outdoor light trap all had large ovaries (mean 1.42 x 0.34 mm) irrespective of stages and parity. The parous rate of unfed stage I or II females collected by the light trap (86.6%) was significantly higher than that of cattle-bait samples (69.6%). Feasibility of using outdoor light trapping in malaria entomology was discussed.