Prenatal exposure to nickel and atopic dermatitis at age 3 years: a birth cohort study with cytokine profiles.

BACKGROUND: Nickel, the fifth most common element on Earth, is the leading inducer of contact allergies in humans, with potent immunological effects. Nickel-induced contact allergies predominantly affect females. Maternal exposure to nickel has been associated with several developmental abnormalities. However, how a maternal nickel exposure affects the development of atopic diathesis and immune abnormalities in children has never been addressed. OBJECTIVES: We aimed to determine whether maternal nickel exposure affects the development of atopic dermatitis and immune abnormalities in their children. METHODS: Using a birth cohort study, we analysed 140 mother-child pairs recruited in 2012-2015 from central Taiwan. Maternal exposure to nickel was estimated using urinary nickel levels measured by inductively coupled plasma mass spectrometry (ICP-MS). The serum levels of 65 analytes and IgE in 3-year-old children were profiled with a multiplex ELISA. The correlation between the maternal urinary nickel concentration and serum analyte levels was assessed using Spearmen's correlation. Multivariant regression analysis was performed to evaluate the association between maternal urinary nickel levels and serum analyte concentrations in their children. RESULTS: The geometric means of the maternal urinary nickel and the children's serum IgE levels were 2.27 µg/L and 69.71 IU/mL, respectively. The maternal nickel exposure was associated with increased serum levels of IL-1ß, IL-2, TNF-α, and leukaemia inhibitory factor (LIF) but with decreased serum levels of matrix metalloproteinase-1 (MMP-1), IL-2R, and eotaxin-1 in the children. In addition, the development of childhood atopic dermatitis at 3 years old was significantly associated with the child's serum levels of IgE and IL-2R, but it was negatively associated with the maternal nickel exposure. CONCLUSIONS: This is the first study showing the potential immunological effects of maternal nickel exposure in their children at an early developmental stage.

First Report of Myrothecium roridum Causing Myrothecium Leaf Spot on Dieffenbachia picta 'Camilla' in Taiwan.

Dumb cane (Dieffenbachia picta (Lodd.) Schott 'Camilla'), family Araceae, is a popular houseplant in Taiwan. During the winter of 2012, dumb canes with dark brown concentric spots on leaves and bright yellow borders were found in a protected ornamental nursery in Wandan township, Pingtung County, Taiwan. On diseased leaves, fungal fruiting bodies were sometimes observed in the concentric lesions and a fungal isolate was consistently isolated from the lesions. A single spore isolate, myr 2-2, was maintained on potato dextrose agar (PDA) for further tests. To fulfill Koch's postulates, the spores of myr 2-2 were suspended in sterilized distilled water containing 0.05% of Tween 20, 1 × 105 conidia ml-1, and then sprayed on leaves of D. picta 'Camilla' growing in polypropylene plant pots (about 7 cm in diameter), three plants per treatment. For the control, three plants were sprayed with sterilized distilled water containing 0.05% of Tween 20. Both inoculated and non-inoculated plants were covered with plastic bags and incubated in a growth chamber at 26 ± 1°C. Nine to 12 days after inoculation, symptoms described above were observed on inoculated plants whereas the plants in control remained healthy. The same fungus was reisolated from inoculated plants but not from the controls. Furthermore, the fungal pathogen was identified using its physiological, morphological, and molecular characteristics. In the mycelial growth test, the diameter of the fungal colony reaches 58.2 mm on PDA at 25°C after 14 days. The colonies were floccose, white to buff, and sporulate in concentric zones with olivaceous black to black sporodochia bearing viscid masses of conidia. Conidia were narrowly ellipsoid with rounded ends. The average size of 100 conidia was 6.25 ± 0.04 × 1.63 ± 0.02 µm. For molecular identification, the rDNA internal transcribed spacer (ITS) of isolate myr 2-2 was PCR amplified using ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'- TCCTCCGCTTATTGATATGC-3') primer pairs (3) and sequenced. The rDNA sequence was deposited in GenBank (KC469695) and showed 100% identity to the Myrothecium roridum isolates BBA 71015 (AJ302001) and BBA 67679 (AJ301995) (4). According to the physiological, morphological (1,2), and molecular characteristics, the fungal isolate was identified as M. roridum Tode ex Fr. To the best of our knowledge, this is the first report of Myrothecium leaf spot caused by M. roridum on D. picta 'Camilla' in Taiwan. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , January 31, 2013. (2) M. Tulloch. Mycol. Pap. 130: 1-42, 1972. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, New York, 1990. (4) Y. X. Zhang et al. Plant Dis. 95:1030, 2011.

First Report of Chrysoporthe deuterocubensis Causing Canker on Syzygium samarangense in Taiwan.

Wax apple (Syzygium samarangense Merr. & Perry, syn. Eugenia javanica Lam.) belongs to the Myrtaceae family is an important economical tree fruit in Taiwan. The total production acreage of wax apple was 5,266 ha in which more than 77% were located in Pingtung County, southern Taiwan, in 2012. Since the winter of 2010, symptoms of withering leaves and cracking branches on wax apple trees were observed in some orchards in Nanjhou and Linbian Townships, Pingtung County. Diseased trees declined gradually and resulted in reduced fruit production. On the bark of diseased twigs and branches, black conidiamata with yellowish orange conidia were usually observed. For diagnosis, tissues from symptomatic branches were excised, surface sterilized with 0.5% sodium hypochlorite, and placed on 2% water agar in petri dishes. A total of four identical fungal isolates were obtained and maintained on potato dextrose agar (PDA). To fulfill Koch's postulates, three twigs of a wax apple tree were wounded with scalpel and inoculated with each of the four isolates, one tree per isolate. A 7-day-old hyphal mat (about 7 × 18 mm) of each fungal isolate was attached on the wound, wrapped with a wet absorbent cotton and Parafilm, and then covered with a layer of aluminum foil. For the control, the twigs of a wax apple tree were inoculated with PDA plugs. The pathogenicity test was repeated once. After 30 days, withering leaves and cracking twigs were observed on inoculated twigs and the same pathogen was reisolated. Conversely, all of the non-inoculated plants remained healthy. Identification of the pathogen was conducted using its morphological, physiological, and molecular characteristics. On malt extract agar, the colony was floccose and white with hazel hues. The optimal temperature for the mycelial growth was 30°C. Conidia were hyaline, and oblong, with the average size of 4.7 ± 0.6 × 2.7 ± 0.2 µm (100 conidia). Ascostromata were semi-immersed in the bark with fusoid asci, eight ascospores per ascus. Ascospores were hyaline, 2-celled, and tapered in both ends, with the average length of 6.8 ± 0.7 × 2.4 ± 0.3 µm (100 ascospores). For molecular identification, the internal transcribed spacer (ITS) of ribosomal DNA and ß-tubulin genes was amplified using the ITS1/ITS4 (3), Bt1a/Bt1b, and Bt2a/Bt2b (1) primer pairs. The gene sequences were deposited in GenBank (Accessions KC792616, KC792617, KC792618, and KC792619 for the ITS region; KC792620, KC792621, KC792622, and KC792623 for Bt1 region, and KC812732, KC812733, KC812734, and KC812735 for Bt2 region) and showed 99 to 100% identity to the Chrysoporthe deuterocubensis isolate CMW12745 (DQ368764 for ITS region; GQ290183 for Bt1 region, and DQ368781 for Bt2 region). In addition, the Bt1 region of the ß-tubulin gene consisted of two restriction sites for AvaI and one restriction site for HindIII. This is identical to the description of C. deuterocubensis, a cryptic species in C. cubensis, by Van Der Merwe et al. (2). According to these results, the pathogen was identified as C. deuterocubensis Gryzenh. & M. J. Wingf. To the best of our knowledge, this is the first report of canker disease caused by C. deuterocubensis on S. samarangense in Taiwan. References: (1) N. L. Glass and G. C. Donaldson. Appl. Environ. Microbiol. 61:1323, 1995. (2) N. A. Van Der Merwe et al. Fungal Biol. 114:966, 2010. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

The SNRPN promoter is not required for genomic imprinting of the Prader-Willi/Angelman domain in mice.

In mice and humans, the locus encoding the gene for small nuclear ribonucleoprotein N (SNRPN/Snrpn), as well as other loci in the region are subject to genomic imprinting. The SNRPN promoter is embedded in a maternally methylated CpG island, is expressed only from the paternal chromosome and lies within an imprinting center that is required for switching to and/or maintenance of the paternal epigenotype. We show here that a 0.9-kb deletion of exon 1 of mouse Snrpn did not disrupt imprinting or elicit any obvious phenotype, although it did allow the detection of previously unknown upstream exons. In contrast, a larger, overlapping 4.8-kb deletion caused a partial or mosaic imprinting defect and perinatal lethality when paternally inherited.

Expression of c-MYC under the control of GATA-1 regulatory sequences causes erythroleukemia in transgenic mice.

To study oncogenesis in the erythroid lineage, we have generated transgenic mice carrying the human c-MYC proto-oncogene under the control of mouse GATA-1 regulatory sequences. Six transgenic lines expressed the transgene and displayed a clear oncogenic phenotype. Of these, five developed an early onset, rapidly progressive erythroleukemia that resulted in death of the founder animals 30-50 d after birth. Transgenic progeny of the sixth founder, while also expressing the transgene, remained asymptomatic for more than 8 mo, whereupon members of this line began to develop late onset erythroleukemia. The primary leukemic cells were transplantable into nude mice and syngeneic hosts. Cell lines were established from five of the six leukemic animals and these lines, designated erythroleukemia/c-MYC (EMY), displayed proerythroblast morphology and expressed markers characteristic of the erythroid lineage, including the erythropoietin receptor and beta-globin. Moreover, they also manifested a limited potential to differentiate in response to erythropoietin. Studies in the surviving transgenic line indicated that, contrary to our expectations, the transgene was not expressed in the mast cell lineage. That, coupled with the exclusive occurrence of erythroleukemia in all the transgenic lines, suggests that the GATA-1 promoter construct we have used includes regulatory sequences necessary for in vivo erythroid expression only. Additional sequences would appear to be required for expression in mast cells. Further, our results show that c-MYC can efficiently transform erythroid precursors if expressed at a vulnerable stage of their development.

DNA sequence and comparative analysis of chimpanzee chromosome 22.

Human-chimpanzee comparative genome research is essential for narrowing down genetic changes involved in the acquisition of unique human features, such as highly developed cognitive functions, bipedalism or the use of complex language. Here, we report the high-quality DNA sequence of 33.3 megabases of chimpanzee chromosome 22. By comparing the whole sequence with the human counterpart, chromosome 21, we found that 1.44% of the chromosome consists of single-base substitutions in addition to nearly 68,000 insertions or deletions. These differences are sufficient to generate changes in most of the proteins. Indeed, 83% of the 231 coding sequences, including functionally important genes, show differences at the amino acid sequence level. Furthermore, we demonstrate different expansion of particular subfamilies of retrotransposons between the lineages, suggesting different impacts of retrotranspositions on human and chimpanzee evolution. The genomic changes after speciation and their biological consequences seem more complex than originally hypothesized.

Mannitol-induced acute renal failure.

A 62-year-old man was admitted to the ophthalmologic department for operation of retinal detachment. Mannitol and acetazolamide were prescribed to reduce intraocular pressure. Seven days after operation, gradual onset of drowsy consciousness occurred. The laboratory findings of hypertonic hyponatremia (109 mEq/l), hyperosmolality (341 mosm/kg), metabolic acidosis (pH: 7.17) and acute renal failure (serum creatinine: 8.2 mg/dl) dictated a diagnosis of mannitol-induced acute kidney injury. First, 3% saline was given, but consciousness kept deteriorated with worsened dyspnea and metabolic acidosis. Hemodialysis was then performed subsequently and his consciousness and renal function completely recovered. A special emphasis on the treatment of hypertonic hyponatremia was given.

Non-vitamin K antagonist oral anticoagulants (NOACs) for thromboembolic prevention, are they safe in congenital heart disease? Results of a worldwide study.

BACKGROUND: Current guidelines consider vitamin K antagonists (VKA) the oral anticoagulant agents of choice in adults with atrial arrhythmias (AA) and moderate or complex forms of congenital heart disease, significant valvular lesions, or bioprosthetic valves, pending safety data on non-VKA oral anticoagulants (NOACs). Therefore, the international NOTE registry was initiated to assess safety, change in adherence and quality of life (QoL) associated with NOACs in adults with congenital heart disease (ACHD). METHODS: An international multicenter prospective study of NOACs in ACHD was established. Follow-up occurred at 6 months and yearly thereafter. Primary endpoints were thromboembolism and major bleeding. Secondary endpoints included minor bleeding, change in therapy adherence (≥80% medication refill rate, ≥6 out of 8 on Morisky-8 questionnaire) and QoL (SF-36 questionnaire). RESULTS: In total, 530 ACHD patients (mean age 47 SD 15 years; 55% male) with predominantly moderate or complex defects (85%), significant valvular lesions (46%) and/or bioprosthetic valves (11%) using NOACs (rivaroxaban 43%; apixaban 39%; dabigatran 12%; edoxaban 7%) were enrolled. The most common indication was AA (91%). Over a median follow-up of 1.0 [IQR 0.0-2.0] year, thromboembolic event rate was 1.0% [95%CI 0.4-2.0] (n = 6) per year, with 1.1% [95%CI 0.5-2.2] (n = 7) annualized rate of major bleeding and 6.3% [95%CI 4.5-8.5] (n = 37) annualized rate of minor bleeding. Adherence was sufficient during 2 years follow-up in 80-93% of patients. At 1-year follow-up, among the subset of previous VKA-users who completed the survey (n = 33), QoL improved in 6 out of 8 domains (p ≪ 0.05). CONCLUSIONS: Initial results from our worldwide prospective study suggest that NOACs are safe and may be effective for thromboembolic prevention in adults with heterogeneous forms of congenital heart disease.

Urinary Liver Type Fatty Acid Binding Protein Is Negatively Associated With Estimated Glomerular Filtration Rate in Renal Transplant Recipients With Graft Loss.

BACKGROUND: Liver type fatty acid binding protein (L-FABP) is abundant not only in the liver but also in the kidney and is excreted in urine. Its primary function is to facilitate intracellular long chain fatty acid transport and it might also act as an endogenous antioxidant molecular. The purpose of this study was to investigate whether plasma or urinary L-FABP levels were associated with graft function in renal transplant recipients. PATIENTS AND METHODS: Sixty-seven renal transplant recipients with a mean age of 48.8 years were recruited. The mean duration of renal transplantation was 4131 days. Recipients were divided into 2 groups based on their estimated glomerular filtration rate (eGFR) values: moderate graft function (eGFR ≥60 mL/min/1.73 m2) and low graft function (eGFR <60 mL/min/1.73 m2). Fasting plasma and urinary L-FABP levels were measured. RESULTS: There was no significant difference in plasma L-FABP level between the 2 groups, although recipients in the low graft function group had significantly lower urinary L-FABP level when compared with recipients in the moderate graft function group. Plasma and urinary L-FABP levels were not associated with eGFR in the 67 recipients; however, urinary L-FABP level (ß = -1.24, P = .037) and level adjusted by urinary creatinine (ß = -0.75, P = .046) were significantly negatively associated with eGFR in recipients with low graft function after adjusting for potential confounders. CONCLUSION: Increased urinary L-FABP level seems to be a significant indicator of decreased graft function in renal transplant recipients with loss of graft function.

Distinctive activation patterns in constitutively active and gefitinib-sensitive EGFR mutants.

Mutations in the kinase domain of epidermal growth factor receptor (EGFR) are associated with clinical responsiveness to gefitinib in patients with non-small-cell lung cancers (NSCLC). Recently, we have identified many novel EGFR mutations in NSCLC tissues. In this study, we found that gefitinib could suppress the tyrosine phosphorylation of most EGFR mutants better than the wild-type receptor. However, gefitinib had quite variable growth-suppressive effects on different EGFR mutant-expressing cells. All tested EGFR mutants have high basal phosphorylation at multiple tyrosine residues. Upon EGF stimulation, the mutated EGFRs did not have apparently stronger phosphorylation at tyrosines 845, 992, 1,068, and 1,173 than the wild-type receptor. However, stronger phosphorylation at tyrosine 1,045 was observed in the S768I, L861Q, E709G, and G719S mutants. The E746-A750 deletion mutant was less responsive to EGF than the wild-type and other mutant receptors. The S768I, L861Q, E709G, and G719S mutants were refractory to EGF-induced ubiquitination and had more sustained tyrosine phosphorylation. E709G and G719S also lacked EGF-induced receptor downregulation. Our results indicate that, in addition to sensitivity to gefitinib, EGFR mutations also caused various changes in EGFR's regulatory mechanisms, which may contribute to the constitutive activation of EGFR mutants and oncogenesis in NSCLC.

Regulated expression of globin chains and the erythroid transcription factor GATA-1 during erythropoiesis in the developing mouse.

Erythropoiesis in vertebrates is characterized by sequential changes in erythropoietic site, erythroblast morphology, and hemoglobin synthesis. We have examined the expression of globin chains and the major erythroid transcription factor GATA-1 (previously known as GF-1/NF-E1/Eryf 1) from days 7.5 to 17.5 of mouse development. mRNAs for embryonic (epsilon y2, beta H1, and zeta) and adult (alpha and beta) globin chains were quantitated by RNase protection assays. Switching of globins within the alpha-globin cluster (alpha and zeta) was not strictly coordinated with that within the beta-globin cluster (epsilon y2, beta H1, and beta). Regulation of globin switches during development was primarily transcriptional. Of particular note, we found two developmental switches (beta H1 to epsilon y2 and epsilon y2 to beta) in the mouse, more analogous than previously thought to shifts found in human development. The erythroid transcription factor GATA-1, believed to be a principal regulator of genes expressed in erythroid cells, first appeared in the embryo in yolk sac at the time of blood island formation and remained at a low level during embryonic erythropoiesis (8 to 11 days) relative to that found later in fetal liver (12 to 15 days). The rise in GATA-1 mRNA in fetal liver paralleled and preceded the rapid accumulation of adult beta-globin RNA. RNase protection assays and a GATA-1-specific peptide antiserum were used to establish that a single GATA-1 polypeptide is expressed throughout mouse development. Overall, these findings suggest that the levels of this erythroid transcription factor during development may contribute to the differential gene activation characteristic of definitive versus primitive erythropoiesis.

Hypertension impairs hippocampus-related adult neurogenesis, CA1 neuron dendritic arborization and long-term memory.

Hypertension is associated with neurodegenerative diseases and cognitive impairment. Several studies using spontaneous hypertensive rats to study the effect of hypertension on memory performance and adult hippocampal neurogenesis have reached inconsistent conclusions. The contradictory findings may be related to the genetic variability of spontaneous hypertensive rats due to the conventional breeding practices. The objective of this study is to examine the effect of hypertension on hippocampal structure and function in isogenic mice. Hypertension was induced by the '2 kidneys, 1 clip' method (2K1C) which constricted one of the two renal arteries. The blood pressures of 2K1C mice were higher than the sham group on post-operation day 7 and remained high up to day 28. Mice with 2K1C-induced hypertension had impaired long-term, but not short-term, memory. Dendritic complexity of CA1 neurons and hippocampal neurogenesis were reduced by 2K1C-induced hypertension on post-operation day 28. Furthermore, 2K1C decreased the levels of hippocampal brain-derived neurotrophic factor, while blood vessel density and activation status of astrocytes and microglia were not affected. In conclusion, hypertension impairs hippocampus-associated long-term memory, dendritic arborization and neurogenesis, which may be caused by down-regulation of brain-derived neurotrophic factor signaling pathways.

Three-dimensional analysis for radio-frequency ablation of liver tumor with blood perfusion effect.

Increase of temperature above 50 approximately 60 degrees C for few minutes by the emitted radio-frequency (RF) energy has been shown to be able to denaturate the intracellular proteins and destruct membranes of tumor cells. To improve the efficacy of this thermal therapy, it is important to investigate factors that may affect the RF heating characteristics for the hepatocellular carcinoma and metastatic liver tumors. In order to make sure the applied RF energy is adequate to ablate the target tumor, a 3D thermoelectric analysis for the system consisting of liver, liver arteries and 4 mm diameter tumor is conducted. The effect of blood perfusion is addressed in this study.

Genetic heterogeneity of familial primary cutaneous amyloidosis: lack of evidence for linkage with the chromosome 10 pericentromeric region in Chinese families.

Primary cutaneous amyloidosis is a relatively common skin disease in Southeast Asia, South America, and the Republic of China. Although most cases are sporadic, some patients have a family history, suggesting that genetic factors may play a role in its pathogenesis. Some patients with multiple endocrine neoplasia type 2A also have a clinical picture of primary cutaneous amyloidosis. It is thus suggested that the gene of familial primary cutaneous amyloidosis is linked to the pericentromeric region of chromosome 10, the location of the RET proto-oncogene. We have carried out linkage analysis in seven families with cutaneous amyloidosis using four dinucleotide repeat markers from the RET region. Negative lod scores at all recombination frequencies were obtained. We thus conclude that there is no evidence for linkage between Chinese families with primary cutaneous amyloidosis and the pericentromeric region of chromosome 10. The distinct genetic basis, plus their apparent phenotypic differences in sex ratio, age of onset, and sites of cutaneous lesions, suggests that familial primary cutaneous amyloidosis includes clinical subtypes attributable to genetic heterogeneity.

Molecular cloning and characterization of a human brain-specific gene implicated in neuronal differentiation.

A 2.5 kb human cDNA clone containing a CAG trinucleotide repeat, designated HB20, was isolated from a human fetal brain library. Northern analysis on multi-tissue blots and various cell lines confirmed that HB20 is specifically expressed in the brain. Its expression is low in two glioma cells, moderate in a neuron precursor cell, NT2, but absent in lymphoma, cervical carcinoma, or colonic carcinoma cells. Significant increase of HB20 mRNA was shown along with retinoic acid-induced terminal differentiation of NT2 cells into neuron cells, hNT. Homology comparison of the predicted HB20 amino acid sequence with the current database revealed that it belongs to a newly recognized protein family composed of nucleosome assembly proteins and SET proto-oncogene, which has been shown to interact specifically with B-type cyclins involved in the control of cell proliferation. Together with the detection of nuclear localization signals and apparent nuclear distribution of expressed protein, HB20 is likely to be a brain-specific nuclear protein, functioning in the process of neuronal differentiation.

Effects of cartap on isolated mouse phrenic nerve diaphragm and its related mechanism.

Cartap, a nereistoxin analogue pesticide, is reported to have no irritation to eyes in rabbits. However, we have demonstrated recently that cartap could actually cause acute death in rabbits via ocular exposure. Our preliminary study with isolated mouse phrenic nerve diaphragms has shown that instead of neuromuscular blockade, cartap caused muscular contracture. The objective of the study was to examine the effect of cartap on the neuromuscular junction in more detail and to investigate its possible underlying mechanism with isolated mouse phrenic nerve diaphragms and sarcoplasmic reticulum (SR) vesicles. Cartap or nereistoxin at various concentrations was added in the organ bath with isolated mouse phrenic nerve diaphragm and both nerve- and muscle-evoked twitches were recorded. Instead of blocking the neuromuscular transmission as nereistoxin did, cartap caused contracture in stimulated or quiescent isolated mouse phrenic nerve diaphragm. Both the cartap-induced muscular contracture force and the time interval to initiate the contracture were dose-dependent. The contracture induced by cartap was not affected by the pretreatment of the diaphragm with the acetylcholine receptor blocker alpha-bungarotoxin; the Na(+) channel blocker tetrodotoxin; or various Ca(2+) channel blockers, NiCl(2), verapamil, and nifedipine. On the contrary, the contracture was significantly inhibited when the diaphragm was pretreated with ryanodine or EGTA containing Ca(2+)-free Krebs solution or in combination. This suggested that both internal and extracellular Ca(2+) might participate in cartap-induced skeletal muscle contracture. Moreover, cartap inhibited the [(3)H]-ryanodine binding to the Ca(2+) release channel of SR in a dose-dependent manner. Additionally, cartap could induce a significant reduction in Ca(2+)-ATPase activity of SR vesicles at a relatively high dose. The results suggested that cartap might cause the influx of extracellular Ca(2+) and the release of internal Ca(2+), with subsequent induction of muscular contracture in the isolated mouse phrenic nerve diaphragm. Based on these findings, we propose that the acute death of rabbits following ocular exposure to cartap might have resulted from respiratory failure secondary to diaphragm contracture.

Congenital erythropoietic porphyria. A mild variant with low uroporphyrin I levels due to a missense mutation (A66V) encoding residual uroporphyrinogen III synthase activity.

BACKGROUND AND DESIGN: Congenital erythropoietic porphyria, an inborn error of heme biosynthesis, results from the deficient activity of the enzyme uroporphyrinogen III synthase. The clinical manifestations in unrelated patients with this autosomal recessive disorder are remarkedly variable, ranging from mild cutaneous involvement to severe transfusion-dependent hemolytic anemia. Biochemical and molecular studies were undertaken to investigate the nature of the unusually mild phenotype in a 15-year-old boy with only cutaneous manifestations. RESULTS: The proband's levels of total porphyrins, urinary uroporphyrin I, and erythrocyte coproporphyrin I were elevated, but not as dramatically as in other patients with this porphyria. Interestingly, the erythrocyte uroporphyrinogen III synthase activity in the proband was about 21% of the normal mean, indicating the presence of significant residual activity. In cultured lymphoblasts from the proband, his father, and mother, the enzymatic activities were 10%, 70%, and 50% of the normal mean, respectively. Molecular analyses revealed that the proband was heteroallelic for two uroporphyrinogen III synthase missense mutations: the C73R allele inherited from his mother and the A66V allele transmitted by his father. The A66V allele encoded residual enzymatic activity in vitro while the C73R allele did not. CONCLUSIONS: The A66V allele accounted for the proband's low levels of porphyrin accumulation and mild clinical manifestations. Such genotype-phenotype correlations should provide understanding of the remarkable clinical variability in other patients with this inherited porphyria.

A study of cytokeratin profiles in localized cutaneous amyloids.

The major component of localized cutaneous amyloids may be derived from cytokeratin (CK). However, the CK profiles of primary cutaneous amyloidosis (PCA) and secondary cutaneous amyloidosis (SCA) remain obscure. Paraffin-embedded sections of skin tissue from 64 patients with PCA, 111 with SCA and 3 with systemic amyloidosis were analyzed immunohistochemically using 12 different polyclonal or monoclonal anti-CK antibodies (34betaE12, MNF116, LP34, AE1/AE3, anti-CK1, CK5, CK6, CK7, CK10, CK14, CK16 and CK17). In addition, frozen skin tissues from 12 patients with PCA were analyzed for comparison with the paraffin-embedded tissue. In all 64 PCA paraffin sections, the amyloid deposits were immunopositive for anti-CK5 antibody and 34betaE12. In all 12 frozen sections of PCA, the amyloid deposits were immunopositive for anti-CK5 antibody, 34betaE12, MNF116 and LP34, and seven (58.3%), three (25%) and one (8.3%) were immunopositive for anti-CK1, CK14, and CK10 antibodies, respectively. In all SCA sections, the amyloid deposits were immunopositive for CK5 and 34betaE12. In addition, MNF116 immunolabeled amyloids of all sections from patients with basal cell carcinoma and trichoepithelioma, and MNF116 and LP34 immunolabeled amyloids of sections from patients with porokeratosis. Our results indicate that CK5 is the major CK present in the amyloid deposits of PCA and SCA, and "amyloid-K" is mainly derived from basal keratinocytes.