Screening of the Men1 gene and discovery of germ-line and somatic mutations in apparently sporadic parathyroid tumors

Hyperparathyroidism is the first manifestation in a majority of multiple endocrine neoplasia (MEN1) patients. To discriminate between sporadic and hereditary parathyroid tumors and characterize MEN1 somatic mutations, we examined MEN1 gene mutations in patients who had undergone surgery for sporadic parathyroid tumors. DNA was extracted from fresh frozen parathyroid tumor specimens from 112 patients as well as from peripheral blood leukocytes from 64 of the 112 patients. Sequence analysis was performed to examine exons 2-10 of the MEN1 gene for mutations. Loss of heterozygosity (LOH) was also examined by an analysis of codon 418 and 541, which lie within a polymorphic region of MEN1. Somatic MEN1 mutations were found in 25 of the 112 patients (22%). Two patients had two point mutations (508del33 and Y341X and 363insT and 1767delT, respectively). A total of 27 mutations were characterized, 20 of which have not been reported previously. There were 7 nonsense mutations, 10 frameshift mutations, 2 splice site deletions, 5 missense mutations, and 3 in-frame mutations. Nineteen mutations (70%) predicted truncation of the menin protein. Germ-line MEN1 mutations were found in 3 of 64 patients (5%) who had no family history of endocrine tumors associated with MEN1, and these patients were identified as MEN1 gene probands. LOH at the MEN1 locus was detected in three parathyroid tumors showing germ-line mutation. LOH was significantly frequent in parathyroid tumors with somatic MEN1 mutations (15 of 22 tumors, 68%) but not in those without germ-line or somatic MEN1 mutations (14 of 51 tumors, 28%; P = 0.0011). Our findings suggest that alterations of both alleles of the MEN1 gene may be associated not only with endocrine tumors of affected MEN1 patients but also with sporadic parathyroid tumors. Germ-line MEN1 gene analysis can distinguish heritable from nonheritable parathyroid tumors, and MEN1 gene evaluation of patients with apparently sporadic parathyroid tumor is recommended before parathyroid surgery.

IgE antibody to fish gelatin (type I collagen) in patients with fish allergy

BACKGROUND

Most children with anaphylaxis to measles, mumps, and rubella vaccines had shown sensitivity to bovine gelatin that was included in the vaccines. Recently, it was found that bovine type I collagen, which is the main content in the gelatin, is a major allergen in bovine gelatin allergy. Fish meat and skin also contain type I collagen.

OBJECTIVE

The present study was designed to investigate IgE antibody to fish gelatin in children with fish allergy.

METHODS

Serum samples were taken from patients in 3 groups: (1) 10 patients with fish allergy and specific IgE to fish meat; (2) two patients with allergies to both fish meat and bovine gelatin and specific IgE to fish meat and bovine gelatin; and (3) 15 patients with atopic dermatitis and specific IgE to fish meat. Various fish gelatins (type I collagen) were prepared from fish skin. IgE antibody to fish gelatin was analyzed by using ELISA and immunoblotting.

RESULTS

Of 10 patients with fish allergy, 3 had specific IgE to fish gelatin. Of two patients with fish allergy and bovine gelatin allergy, all had specific IgE to fish gelatin. Of 15 patients with atopic dermatitis and specific IgE to fish meat, 5 had specific IgE to fish gelatin. Furthermore, IgE from pooled serum of the patients reacted with both the alpha1 and alpha2 chains of fish type I collagen in immunoblots. There is cross-reactivity among gelatins from various fishes, but there is little cross-reactivity between fish and bovine gelatins.

CONCLUSION

Some fish-sensitive patients possessed IgE antibody to fish gelatin. Fish gelatin (type I collagen) might be an allergen in subjects with fish allergy.

Increased number of glucocorticoid receptor-beta-expressing cells in the airways in fatal asthma

BACKGROUND

We have recently demonstrated an increased number of glucocorticoid receptor-beta (GRbeta)-positive cells in steroid-insensitive subjects with severe asthma. Insensitivity to steroids may be a major contributing factor in fatal asthma; however, no such direct evidence has been report previously.

OBJECTIVE

Our aims were to investigate the expression of GRbeta immunoreactivity, an endogenous inhibitor of steroid action previously associated with steroid insensitivity, within the airways of patients who died of slow-onset fatal asthma and to compare its expression in patients with emphysema and in nonasthmatic subjects who died of unrelated causes. Sections from airways, both large and small, were obtained from 7 patients who died of asthma, 6 who died from emphysema, and 8 who died from nonpulmonary diseases. Sections from lungs of 6 patients with mild asthma whose lungs were resected for carcinoma were also included as controls.

METHODS

Tissue samples were processed for immunocytochemistry with a polyclonal antibody to GRbeta with use of the avidin-biotin technique and with monoclonal CD3, major basic protein, CD68, and elastase antibodies with the alkaline phosphatase-anti-alkaline phosphatase technique. Sequential immunocytochemistry was performed to phenotype the GRbeta immunoreactive cells. Tissue sections from both large (>2 mm) and small (<2 mm) airways were examined.

RESULTS

There was a significantly greater number of GRbeta immunoreactive cells in fatal asthma compared with emphysema and controls (P <.001 and P <.05, respectively). There was no difference in the expression of GRbeta in emphysema compared with controls. GRbeta immunoreactivity was also significantly higher in fatal asthma compared with mild asthma. The expression of GRbeta in the small airways of patients with severe asthma did not differ significantly from that in the large airways. The majority of GRbeta-positive cells were T cells and to a lesser extent eosinophils, macrophages, and neutrophils.

CONCLUSION

The results of this study support the association of GRbeta expression with fatal asthma and suggest that alternative anti-inflammatory agents need to be considered in the acute setting for patients who are not responding to steroid therapy.

Induction of hepatitis C virus-specific cytotoxic T lymphocytes in mice by an intrahepatic inoculation with an expression plasmid

We assessed the possibility of intrahepatic inoculation with a plasmid encoding hepatitis C virus (HCV) proteins to elicit HCV-specific cytotoxic T lymphocytes (CTL) in mice as a conventional animal model of HCV infection. BALB/c mice were intrahepatically or intramuscularly inoculated with an expression plasmid DNA encoding HCV structural proteins under the control of the elongation factor 1-alpha promoter. Expressions of HCV-core protein and envelope proteins (E1 and E2) in hepatocytes were detected immunohistochemically 6 days after inoculation. CTL responses were examined using target cells either pulsed with a specific peptide or infected with a recombinant vaccinia virus expressing HCV structural protein. Both intrahepatically and intramuscularly DNA-inoculated mice developed CD8(+), MHC class I-restricted CTL responses that recognized the peptide pulsed as well as HCV proteins expressing target cells. These studies demonstrated the usefulness of a murine model of HCV infection induced by direct intrahepatic DNA inoculation for understanding the immunopathogenic mechanisms in HCV infection.

Interferon-gamma increases IL-12 mRNA expression and attentuates allergic late-onset airway responses in the Brown Norway rat

Interferon gamma is a T-helper cell (Th)-1-type cytokine that has been suggested to inhibit the development of an atopic Th2-type profile of cytokine expression. The aim of this study was to investigated the effect of exogenous rat interferon gamma on antigen-induced airway responses, and on Th1 and Th2-type cytokine messenger ribonucleic acid (mRNA) expression in the Brown Norway rat. Rats were actively sensitized to ovalbumin and 14 days later underwent an aerosolized ovalbumin challenge. Animals were intratracheally administered either interferon gamma (3,000 U) or control solvent 30 min prior to, and 2 and 4 h following, antigen challenge. Lung resistance was monitored over an 8-h time period. Using in situ hybridization and immunocytochemistry, the levels of Th1- (interleukin-12) and Th2-type (interleukin4 and -5) cytokine mRNA, and major basic protein expression in the bronchoalveolar lavage fluid of these rats 8 h after ovalbumin challenge were also determined. Administration of interferon gamma attenuated the development of the late-onset airways response in ovalbumin-sensitized antigen-challenged rats (p<0,05). The expression of interleukin-4 and -5 mRNA in the bronchoalveolar lavage fluid of interferon gamma treated rats was significantly attenuated compared to ovalbumin-challenged saline-treated controls (p<0.001). This was accompanied by a significant increase in the expression of interleukin-12 mRNA, and a reduction in eosinophil numbers. Intratracheal administration of interferon gamma modulates the allergic late-onset airways response in rats, and this is associated with a reduction in the expression of T-helper cell 2-type cytokines and an increase in interleukin-12 messenger ribonucleic acid expression within the airways. The present results support a role for interferon gamma in the pathophysiology of acute allergic airway responses, possibly by virtue of its ability to modulate T-helper cell 1- 2-type cytokine expression within the lungs.

Interleukin-9 upregulates mucus expression in the airways

Interleukin (IL)-9 has recently been shown to play an important role in allergic disease because its expression is strongly associated with the degree of airway responsiveness and the asthmatic-like phenotype. IL-9 is a pleiotropic cytokine that is active on many cell types involved in the allergic immune response. Mucus hypersecretion is a clinical feature of chronic airway diseases; however, the mechanisms underlying the induction of mucin are poorly understood. In this report, we show that IL-9 regulates the expression of a subset of mucin genes in lung cells both in vivo and in vitro. In vivo, the constitutive expression of IL-9 in transgenic mice results in elevated MUC2 and MUC5AC gene expression in airway epithelial cells and periodic acid-Schiff-positive staining (reflecting mucous glycogenates). Similar results were observed in C57BL/6J mice after IL-9 intratracheal instillation. In contrast, instillation of the T helper 1-associated cytokine interferon gamma failed to induce mucin production. In vitro, our studies showed that IL-9 also induces expression of MUC2 and MUC5AC in human primary lung cultures and in the human muccoepidermoid NCI-H292 cell line, indicating a direct effect of IL-9 on inducing mucin expression in these cells. Altogether, these results suggest that upregulation of mucin by IL-9 might contribute to the pathogenesis of human inflammatory airway disorders, such as asthma. These data extend the role of the biologic processes that IL-9 has on regulating the many clinical features of asthma and further supports the IL-9 pathway as a key mediator of the asthmatic response.

Absence of somatic RET gene mutation in sporadic parathyroid tumors and hyperplasia secondary to uremia, and absence of somatic Men1 gene mutation in MEN2A-associated hyperplasia

Germline mutations of the MEN1 gene are found in more than 85% of multiple endocrine neoplasia type 1 (MEN 1) patients, and germline mutations of the RET gene are found in more than 95% of multiple endocrine neoplasia type 2 (MEN2) patients. Parathyroid hyperplasia is seen in more than 90% of MEN 1 and about 15% of MEN2A patients. To date, somatic MEN1 mutations are reported in about 20% of sporadic parathyroid tumors. To elucidate the genetic basis of parathyroid tumor development, we examined somatic RET gene mutations in sporadic parathyroid tumors and hyperplasia secondary to uremia, and somatic MEN1 gene mutations in parathyroid hyperplasia from MEN2A patients. A total of 145 parathyroid tumors comprising 129 sporadic parathyroid tumors, 14 hyperplastic lesions secondary to uremia, and two hyperplastic lesions from MEN2A patients were examined. DNA was extracted from fresh frozen parathyroid tissue. Exons 2-10 of the MEN1 gene and exons 10 and 11 of the RET gene were sequenced. No somatic RET gene mutations were found in the 129 sporadic parathyroid tumors or 14 parathyroid hyperplastic lesions secondary to uremia. No somatic MEN1 gene mutations were found in the two parathyroid hyperplasia from MEN2A patients. These data suggest that RET gene mutation may not be involved in the development of sporadic parathyroid tumors and hyperplasia secondary to uremia and that MEN1 gene mutation may not be or is rarely associated with development of parathyroid hyperplasia in MEN2A patients.

Upregulation of the transcription factor GATA-3 in upper airway mucosa after in vivo and in vitro allergen challenge

BACKGROUND

Allergic rhinitis is a complex upper airways disorder characterized by the infiltration of eosinophils and T(H2)-type T lymphocytes. GATA-3 is a novel transcription factor recently shown to regulate IL-5 and, possibly, IL-4 gene expression. We previously reported that GATA-3 is increased within the bronchial mucosa of allergic asthmatic subjects compared with control subjects.

OBJECTIVE

In the present study we set out to determine whether there is also an increased number of cells expressing GATA-3 messenger (m)RNA within the nasal mucosa of patients with allergic rhinitis.

METHODS

Inferior turbinate biopsy specimens were obtained from patients with allergic rhinitis and nonatopic control subjects before and after local allergen provocation in vivo. To assess the contribution of resident cells expressing GATA-3 mRNA, we also performed isolated explant studies in which nasal mucosal tissue from subjects with allergic rhinitis and nonatopic control subjects was cultured in allergen-treated medium. The presence of mRNA coding for GATA-3, IL-5, IL-4, IL-13, and GM-CSF was assessed by using in situ hybridization.

RESULTS

The number of GATA-3 mRNA(+) cells was increased after local allergen provocation in vivo (increase in GATA-3 mRNA(+) cells [mean +/- SEM]: subjects with allergic rhinitis, 11.3 +/- 8.7; control subjects, 1.2 +/- 4.1; P <.05) and in explanted nasal mucosa in vitro (subjects with allergic rhinitis, 10. 2 +/- 3.8; control subjects, 2.7 +/- 4.4; P <.05). The gene expression of GATA-3 was significantly correlated to the numbers of IL-5 (r = 0.87) and GM-CSF (r = 0.79) mRNA(+) cells but not with IL-4 or IL-13 mRNA(+) cells.

CONCLUSION

In summary, the expression of the transcription factor GATA-3 was increased after allergen challenge, and this was evident in the absence of de novo inflammatory cell recruitment. GATA-3 may be a potential target in the treatment of allergic diseases, such as rhinitis.

Evidence for increased expression of eotaxin and monocyte chemotactic protein-4 in atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with tissue eosinophilia and the activation of T lymphocytes. The novel eosinophil chemoattractants, eotaxin and monocyte chemotactic protein (MCP)-4, are up-regulated at sites of allergic inflammation, yet their contribution to the pathophysiologic mechanisms of AD remains to be determined.

OBJECTIVE

We sought to investigate the expression of eotaxin and MCP-4 in acute and chronic lesions from patients with AD and to determine their relationship to the numbers of resident inflammatory cells.

METHODS

With use of in situ hybridization, the expression of eotaxin and MCP-4 messenger RNA (mRNA) in skin biopsy specimens from patients with acute and chronic AD skin lesions was compared with that of uninvolved skin from these patients and skin from healthy volunteers.

RESULTS

There was a constitutive expression of eotaxin and MCP-4 mRNA in skin biopsy specimens from healthy subjects. Positive signal for chemokine mRNA was observed both within the epidermis and inflammatory cells (macrophages, eosinophils, and T cells) of the subepidermis in AD skin lesions. Within the subepithelium acute and chronic skin lesions exhibited a significant increase in the numbers of eotaxin and MCP-4 mRNA-positive cells compared with uninvolved skin (P <.01), whereas the numbers of eotaxin and MCP-4 mRNA-positive cells were significantly higher in chronic AD compared with acute AD skin lesions (P <.005, P <.001, respectively). Correlations were observed between the expression of eotaxin and MCP-4 mRNA and the presence of eosinophils and macrophages, respectively, in AD lesions (r(2) = 0.84, r(2) = 0.94).

CONCLUSION

There is an increased expression of eotaxin and MCP-4 in acute and chronic lesions, suggesting that these chemotactic factors play a major role in the pathophysiologic mechanisms of AD.

Seasonal changes in calcium homeostasis affect the incidence of postoperative tetany in patients with Graves' disease

BACKGROUND

We have found that postoperative tetany occurs in patients with Graves' disease who have secondary hyperparathyroidism caused by a deficiency in calcium and vitamin D concomitant with transient hypoparathyroidism after surgery. There are seasonal variations in serum 25-hydroxyvitamin D (25[OH]D) concentrations. The purpose of this study was to investigate the effects of seasonal changes in calcium homeostasis on the incidence of postoperative tetany in patients with Graves' disease who undergo subtotal thyroidectomy.

PATIENTS AND METHODS

A prospective study was carried out to investigate sequential changes in serum levels of intact parathyroid hormone (iPTH), calcium and other electrolytes, 25(OH)D, and 1,25-dihydroxyvitamin D (1,25[OH]2D) in female patients with Graves' disease who underwent subtotal thyroidectomy during the summer (n = 89) and during the winter (n = 89).

RESULTS

The serum levels of calcium, magnesium, and 25(OH)D were significantly higher, but iPTH levels and 1,25(OH)2D levels were lower in summer than in winter. The percentage of vitamin D deficiency (25(OH)D < 25 nmol/L) was 23% in summer and 62% in winter (P < .001). iPTH was below the detection limit on the first postoperative day in 15 patients (13.8%) in summer and in 13 patients (11.4%) in winter. In summery, tetany developed in only 4 of 15 patients and in one patient whose iPTH level was below normal (incidence of tetany, 5.6%). In winter, however, tetany developed in 6 of 13 patients and in 4 patients whose iPTH level was below normal (incidence of tetany, 11.2%).

CONCLUSIONS

Patients with Graves' disease are more susceptible to calcium and vitamin D deficiency during the winter than during the summer, resulting in the tendency toward a higher incidence of postoperative tetany in winter.

Survival-promoting activity of IL-7 on IL-2-dependent cytotoxic T lymphocyte clones: resultant induction of G1 arrest

Interleukin-7 (IL-7) is essential for both T cell and B cell development. Recent studies have suggested that IL-7 also functions as a survival-promoting factor for resting and activated T cells. In this study we examined the effects of IL-7 on survival and cytotoxicity of tumor-specific CD8(+) cytotoxic T lymphocyte (CTL) clones established and maintained either with IL-2 alone or with a combination of IL-2 and IL-7. While the CTL clones cultured in IL-2 alone died around day 10, the CTL clones cultured in the presence of IL-2 and IL-7 survived for more than 4 weeks after seeding. The long-term survival of the latter was correlated with the presence of IL-7 in the medium. In addition, IL-7 alone prolonged survival of other IL-2-dependent CTL clones after the removal of IL-2. IL-7 maintained the CTLs in G1 arrest after a slight proliferation during the initial phase during which low-level but sustained DNA synthesis was observed. However, there was no direct correlation between DNA synthesis and enhancement of long-term survival by IL-7 as demonstrated by the inhibiting proliferation of the CTL clones with the protein kinase inhibitor genistein. During long-term survival in the presence of IL-7, the cytotoxic activities of the CTL clones decreased gradually to background levels although they were restored soon after the next passage. These results suggested that IL-7 had the ability to set machinery in motion against apoptosis in the IL-2-dependent CTL clones. Such an effect of IL-7 might play a role in vivo in the process leading activated T cells to the resting, that is, memory state.

Comparison of Fas- versus perforin-mediated pathways of cytotoxicity in TCR- and Thy-1-activated murine T cells

T cell-mediated cytotoxicity can be triggered by cross-linking of TCR or Thy-1 surface proteins. While the TCR-triggered signaling initiates both perforin- and Fas ligand (FasL)-Fas-mediated mechanisms of cytotoxicity, it was not clear which mechanism was utilized by Thy-1-triggered signals and which pathway of cytotoxicity was triggered at low levels of antigen expression. It is shown that glycophosphatidylinositol-linked surface glycoprotein Thy-1 preferentially activates FasL-Fas- but not perforin-mediated cytotoxicity. This is explained by the lesser intensity of Thy-1-mediated signaling in T cells. The data suggest that Thy-1-triggered Fas-mediated cytotoxicity is completely dependent on cross-talk between Thy-1 and TCR signals since mutations in TCR-CD3 complex molecules or inhibition of tyrosine kinases or calcineurin abolished or strongly inhibited Thy-1-triggered FasL-Fas-mediated cytotoxicity. Lower concentrations of antigenic peptide or levels of cross-linking with anti-TCR-CD3 mAb are required to trigger Fas-mediated than perforin-mediated cytotoxicity by different cytotoxic T lymphocyte (CTL) lines and clones, and it is shown that cross-linking of Thy-1 is much less efficient in triggering accumulation of second messengers (intracellular Ca(2+)) than cross-linking of TCR on CTL. Taken together, these data reflect the possibility of differential activation of FasL and/or perforin pathways of cytotoxicity depending on the nature of activating stimuli and surface receptor.

Inhibition of immunoglobulin E response to Japanese cedar pollen allergen (Cry j 1) in mice by DNA immunization: different outcomes dependent on the plasmid DNA inoculation method

To develop a new immunotherapy for Japanese cedar (Cryptomeria japonica; CJ) pollinosis, we evaluated the use of DNA immunization by inoculating mice with plasmid DNA encoding Cry j 1 as a CJ pollen major allergen (pCACJ1). Repeated intramuscular (i.m.) inoculation of BALB/c mice with pCACJ1 produced anti-Cry j 1 antibody responses, which were predominately of the immunoglobulin G2a (IgG2a) type. Furthermore, this inoculation suppressed immunoglobulin E (IgE) and IgG1 antibody responses to subsequent alum-precipitated Cry j 1 injections. Splenic T cells isolated from mice inoculated with pCACJ1 i.m. secreted interferon-gamma (IFN-gamma), but not interleukin (IL)-4, in vitro upon stimulation with Cry j 1 as well as with p277-288, a peptide corresponding to the T-cell epitope of Cry j 1. In contrast, inoculation of BALB/c mice with pCACJ1 by gene gun injection caused response predominantly of the IgG1 type, and enhanced production of anti-Cry j 1 IgE antibodies to subsequent alum-precipitated Cry j 1 injections. Splenic T cells isolated from pCACJ1-innoculated mice by gene gun injection secreted both IFN-gamma and IL-4 in vitro, upon stimulation with Cry j 1 as well as with p277-288. These findings suggest that i.m. inoculation with pCACJ1 effectively elicits Cry j 1-specific T helper 1 (Th1)-type immune responses, resulting in inhibition of the IgE response to Cry j 1.

Down-regulation of antigen-specific antibody production by TCR antagonist peptides in vivo

The efficacy of TCR antagonist peptides in inhibition of antigen-specific antibody production and T cell responses in vivo was evaluated. Among amino acid-substituted analogs of a peptide corresponding to residues 119 - 133 of bovine beta-lactoglobulin (p119 - 133), pR124Q and pD129S, prepared by substitution of Gln and Ser for Arg(124) and Asp(129), respectively, have been shown to display TCR antagonist activity for three out of four distinct p119 - 133-specific T cell clones and for polyclonal T cells derived from p119 - 133-immunized C57BL / 6 mice. Both pD129S and pR124Q inhibited in vivo priming and subsequent activation of T cells by p119 - 133 when co-injected with p119 - 133 into mice, as shown by the decreased proliferation of T cells in response to p119-133 in vitro. pD129S significantly inhibited production of anti-p119 - 113 antibodies of IgG1, IgG2b and IgE isotype in vivo when co-injected into mice together with p119 - 133 at the time of the first immunization. However, pR124Q was totally ineffective in inhibition of the antibody responses. Anti-p119 - 133 antibodies from p119 - 133-immunized mice could bind to pR124Q but not to pD129S, suggesting that the difference in cross-reactivity is responsible for the different effect of these two peptides on specific antibody production. Our findings demonstrate that a single TCR antagonist peptide can inhibit antigen-specific polyclonal antibody production when this antagonist peptide does not cross-react with the antibody elicited in response to an antigenic peptide.

Alpha-glucosidase inhibitors from clove (Syzgium aromaticum)

The ellagitannins, casuarictin and eugeniin, were isolated as rat intestinal maltase inhibitors from methanol extracts of clove (Syzgium aromaticum). Eugeniin showed inhibitory activity with an IC50 value of 10(-3) M. A structure-activity relationship study among the isolates and their related compound, penta-O-galloyl-beta-D-glucose, indicates that an increasing number of galloyl units in the molecule might lead to an increase in the inhibitory activity. Eugeniin also inhibited maltase activity toward the human intestinal epithelial cell line, Caco-2.

[Comparison between repeated antigen and acetylcholine-induced bronchoconstriction in development of airway wall thickness in a chronic guinea pig model of asthma]

Asthma is associated with a chronic remodeling of the airways, but it remains to be elucidated whether repeated bronchoconstriction (BC) influences any structural attributes of the lungs. To investigate the role of repeated BC on the morphology of the airways, we chronically exposed guinea pigs to an aerosol of acetylcholine (ACH) over a period of 6 months. The guinea pigs were challenged with either ACH or saline daily for 10 days and thereafter were challenged once a week. To compare repeated BC with a chronic model of allergic inflammation, an additional group of animals were sensitized to aerosolized ovalbumin (OA) and subsequently exposed with OA. The airway wall area and basement membrane (BM) thickness were measured by standard morphometric techniques. Both airway wall area and BM thickness were significantly increased in OA exposed guinea pigs compared with both saline control and AHC-exposed guinea pigs. Our results suggest that persistent bronchoconstriction and/or allergic airway inflammation in asthmatics may contribute to the thickness of the airway wall observed in this disorder. However, repeated acute bronchoconstriction events may not contribute to the increase in the airway wall or BM thickness.

[Effects of Ramadan fasting on the health of Muslims]

The fasting month of Ramadan is the ninth lunar month of the Islamic calendar. It is the most important month for Muslims because in which the Qur'an was revealed, and they abstain from food and drink from dawn to sunset to express their gratitude to God. Eating and drinking is permitted only at night, and Muslims typically eat two meals each day, after sunset and just before dawn. People tend to stay up late watching TV with the family, praying or reading the Qur'an. Ramadan teaches Muslims self-restraint and reminds them of the feelings of the impoverished. On the other hand, the biological effects of changes in lifestyle during Ramadan may also be expected. Some studies have reported substantial weight loss, signs of dehydration, raised serum concentrations of uric acid and cholesterol, etc. during Ramadan. However, these changes are unlikely to have much effect on healthy individuals, because generations of Muslims have undertaken fasting year after year. In conclusion, the observance of the Ramadan fast may produce some ill-effects in patients with some disease, e.g. hypertension, hypercholesterolaemia, hyperuricaemia, hyperglycaemia, and heart, liver and kidney disease.

Theory of curved, clamped, piezoelectric film, air-borne transducers

Differential equations in the cylindrical coordinate system have been solved to calculate vibration mode of a curved, clamped, piezoelectric multilayer film. Type I has two clamps at straight ends with uniform film curvature, and Type II has the same two clamps with nonuniform curvature in which the radii are different for the central region and for side regions. The solutions include a uniform displacement term, flexural waves with sinusoidal terms, and a hyperbolic cosine term. By numerical computations, the vibration modes and frequency response of displacement are shown, as are various transducer performances. Mechanical losses of the layer materials were taken as complex Young's moduli with Q values assumed to be constant with frequency. Numerical calculations for 28-/spl mu/m PVDF with 25-/spl mu/m polyester enforcement have shown that (1) the resonance frequency is not necessarily proportional to the inverse of curvature radius as classical theory describes, and, furthermore, resonance diminishes for a certain range of radii, forming a stop band; (2) a back air cavity thinner than 150 /spl mu/m significantly increases the resonance frequency; (3) Type II generates much higher output pressure than Type I; (4) receiver sensitivities for Type I and Type II are not much different; and (5) the effect of radiation impedance is small leading to /spl sim/7% output reduction.

Presymptomatic detection and treatment of Japanese carriers of the multiple endocrine neoplasia type 2A gene

DNA extracted from the peripheral blood leukocytes of 36 members of five families with multiple endocrine neoplasia (MEN) type 2A was analyzed for mutations of exons 10, 11, 13, 14, and 16 of the RET proto-oncogene by nonisotopic polymerase chain reaction-single-strand conformation polymorphism analysis and automated DNA sequencing. Germline mutations were found in all 9 of the affected individuals and in 6 of the 27 individuals of unknown status. A 70-year-old man who had been completely asymptomatic before genetic diagnosis underwent left adrenalectomy and total thyroidectomy, and was found to have pheochromocytoma and multifocal micromedullary thyroid carcinoma (MTC). A 32-year-old man and a 15-year-old boy, with elevated calcitonin levels detected by the C-cell-stimulation test, but no evident thyroid tumor, underwent total thyroidectomy. Histopathological diagnosis revealed multiple micro MTCs. A 7-year-old girl without evidence of a thyroid tumor or an elevated calcitonin level is being followed up. The remaining two subjects with an evident thyroid tumor and elevated calcitonin levels refused surgery. These results suggest that genetic screening for MEN type 2 afflicted family members can facilitate the presymptomatic detection of gene carriers. Thus, we must carefully evaluate whether immediate prophylactic total thyroidectomy is indicated for gene carriers of MEN 2A without an evident thyroid tumor or elevated calcitonin levels.

Extracapsular invasion of lymph node metastasis. A good indicator of disease recurrence and poor prognosis in patients with thyroid microcarcinoma

BACKGROUND

The majority of patients with thyroid microcarcinoma have a favorable prognosis. However, some patients may die from this tumor. Although the incidence of microcarcinoma is high, to the authors' knowledge no histologic risk factors have been identified. The objective of this study was to establish risk factors for patients with thyroid microcarcinoma.

METHODS

The histologic findings for 1743 surgically excised thyroid microcarcinomas (</=10 mm in greatest dimension) and simultaneously obtained lymph nodes from 324 microcancer patients were reexamined to determine risk factors. Follow-up for the patients was 11.2 +/- 6.3 years (mean +/- standard deviation). These thyroid carcinomas were classified according to the World Health Organization Histological Classification system, and lymph node involvement was classified into two groups: those patients with extracapsular invasion of the lymph node metastasis (ECI) (62 patients) and those patients without (1681 patients). A Fisher exact test, an F test, univariate and multivariate proportional hazards regression analyses, and a Kendall correlation measurement were performed.

RESULTS

No undifferentiated tumors were found among the microcarcinomas. During the follow-up period, 1643 of 1743 patients were alive without recurrence, 25 were alive with recurrence, 71 had died of thyroid-unrelated diseases including 2 patients with recurrence, and 4 had died of recurrent thyroid carcinoma. In total, recurrence was noted in 31 patients. Multivariate proportional hazards regression analysis revealed that the absence of Graves disease (risk ratio = 5) and the presence of ECI (risk ratio = 7) were significant risk factors for disease recurrence. Univariate analysis revealed that patient age and the presence of ECI were significant risk factors for thyroid carcinoma-related deaths.

CONCLUSIONS

The presence of ECI of lymph node metastasis in patients with thyroid microcarcinoma was found to be a significant indicator of disease recurrence and a poorer prognosis.

IgE reactivity to alpha1 and alpha2 chains of bovine type 1 collagen in children with bovine gelatin allergy

BACKGROUND

Anaphylactic reactions to measles, mumps, and rubella vaccines, including gelatin as a stabilizer, have been reported. It had been found that most of these reactions to live vaccines are caused by the bovine gelatin included in these vaccines. Gelatin mainly includes denatured type I collagen, which consists of alpha1 and alpha2 chains.

OBJECTIVE

The current study was designed to investigate the IgE reactivity to alpha1 and alpha2 chains of bovine type I collagen in gelatin-sensitive children.

METHODS

Serum samples were taken from 10 children who had anaphylaxis to the vaccines and high levels of specific IgE to bovine gelatin. Bovine type I collagen was isolated from bovine skin and then separated to alpha1 and alpha2 chains by column chromatography. IgE reactivity to denatured type I collagen and its alpha1 and alpha2 chains was analyzed by immunoblotting, ELISA, and histamine release from the mast cells passive sensitized with IgE antibodies in pooled serum of the children.

RESULTS

All children had specific IgE to bovine type I collagen. Furthermore, IgE antibodies in their sera reacted with the alpha;2 chain but not with the alpha1 chain. Similarly, the mast cells sensitized with pooled sera in the children showed alpha2 chain-specific histamine release but not alpha1 chain-specific histamine release.

CONCLUSION

In gelatin allergy denatured bovine type I collagen is a major allergen and IgE-binding sites exist in the alpha2 chain of type I collagen.

Attenuated, replication-competent herpes simplex virus type 1 mutant G207: safety evaluation of intracerebral injection in nonhuman primates

This study examined the safety of intracerebral inoculation of G207, an attenuated, replication-competent herpes simplex virus type 1 (HSV-1) recombinant, in nonhuman primates. Sixteen New World owl monkeys (Aotus nancymae [karyotype 1, formerly believed to be A. trivirgatus]), known for their exquisite susceptibility to HSV-1 infection, were evaluated. Thirteen underwent intracerebral inoculation with G207 at doses of 10(7) or 10(9) PFU, two were vehicle inoculated, and one served as an infected wild-type control and received 10(3) PFU of HSV-1 strain F. HSV-1 strain F caused rapid mortality and symptoms consistent with HSV encephalitis, including fever, hemiparesis, meningitis, and hemorrhage in the basal ganglia. One year after G207 inoculation, seven of the animals were alive and exhibited no evidence of clinical complications. Three deaths resulted from nonneurologic causes unrelated to HSV infection, and three animals were sacrificed for histopathologic examination. Two animals were reinoculated with G207 (10(7) PFU) at the same stereotactic coordinates 1 year after the initial G207 inoculation. These animals were alive and healthy 2 years after the second inoculation. Cerebral magnetic resonance imaging studies performed both before and after G207 inoculation failed to reveal radiographic evidence of HSV-related sequelae. Despite the lack of outwardly observable HSV pathology, measurable increases in serum anti-HSV titers were detected. Histopathological examination of multiple organ tissues found no evidence of HSV-induced histopathology or dissemination. We conclude that intracerebral inoculation of up to 10(9) PFU of G207, well above the efficacious dose in mouse tumor studies, is safe and therefore appropriate for human clinical trials.

[Usefulness of bronchoscopy for the diagnosis of atypical pulmonary mycobacteriosis]

In 14 subjects whose chest radiographs showed abnormal shadows during the two years from January 1995 until December 1996, no definite diagnosis could be obtained because sputum, smears and cultures all gave negative results for mycobacteria. Bronchoscopy was therefore performed, revealing atypical mycobacteria in cultures of the bronchial washing fluid for mycobacteria, and the significance of bronchoscopic examinations in cases diagnosed an atypical pulmonary mycobacteriosis was investigated. Most of the subjects (9) were women. Nine subjects had been informed that they had abnormal chest shadows; five had subjective symptoms; bloody sputum, 3 and cough, 2. The characteristics of the shadows were as follows: in the plain radiographs, the main shadows had a mottled or granular appearance in the majority of the patients (9) and there were infiltrative shadows in 3 patients and nodular shadows in another 3. In computed tomograms, the shadows in the vicinity of the pleura appeared as micronodular conglomerates in 12 patients, in 11 of whom bronchiectasis was also present near the shadows. Alveolar infiltrative shadows were present in four cases, and a cavity was seen in only one. Smears of the bronchial washing fluid for mycobacteria were positive in 7 patients, and cultures of this fluid yielded at least 100 colonies in 8 of the 14 subjects for whom the results were positive. By culture, Mycobacterium avium complex (MAC) was identified in 13 patients, but eleven of these in whom the bronchial washing fluid was concurrently tested for MAC by the polymerase chain reaction, only four were MAC-positive. Transbronchial lung biopsies were performed in 11 cases, in which the histological findings of mycobacterial infections showed granuloma in four, and caseation in three. Bronchoscopy is making possible initial-stage diagnosis, which are normally difficult, among the recently growing number of cases of the bronchial form of atypical pulmonary mycobacteriosis and is also useful for reaching definite diagnosis in the early stage.

Neurogenic vasoconstriction as affected by cholinergic and nitroxidergic nerves in dog ciliary and ophthalmic arteries

PURPOSE

To determine the involvement of noradrenergic and other vasoconstrictor nerves in the contraction of ocular arteries and the modification by cholinergic and nitroxidergic nerves of vasoconstrictor nerve function.

METHODS

Changes in isometric tension were recorded in helical strips of the canine posterior ciliary and external ophthalmic arteries denuded of the endothelium, which were stimulated by transmurally applied electrical pulses (5 Hz). Vasoconstrictor mediators were analyzed by pharmacological antagonists, such as prazosin, alpha,beta-methylene ATP, a P2alpha-purinoceptor antagonist, and BIBP3226, a neuropeptide Y receptor antagonist.

RESULTS

Transmural electrical stimulation produced contractions that were potentiated by N(G)-nitro-L-arginine (L-NA), a nitric oxide (NO) synthase inhibitor. The contraction was partially inhibited by prazosin and abolished by combined treatment with alpha,beta-methylene ATP but was not influenced by BIBP3226. Stimulation-induced contraction was attenuated by physostigmine and potentiated by atropine. Contractions induced by exogenous ATP were reversed to relaxations by alpha,beta-methylene ATP. In the strips treated with L-NA, prazosin, and alpha,beta-methylene ATP, the addition of L-arginine elicited relaxations by nerve stimulation. The ATP-induced relaxation was attenuated by aminophylline, whereas neurogenic relaxation was unaffected.

CONCLUSIONS

Ciliary and ophthalmic arterial contractions by nerve stimulation are mediated by norepinephrine and ATP, which stimulate alpha1-adrenoceptor and P2X purinoceptor, respectively. ATP from the nerve is unlikely involved in vasodilatation. Acetylcholine derived from the nerve impairs the neurogenic contraction, possibly by interfering with the release of vasoconstrictor transmitters, and neurogenic NO also inhibits the contraction postjunctionally by physiological antagonism.

Effects of endothelial impairment by saponin on the responses to vasodilators and nitrergic nerve stimulation in isolated canine corpus cavernosum

1. Responsiveness to EDRF-releasing substances and inhibitory nerve stimulation of canine isolated penile corpus cavernosum with and without saponin treatment were investigated. 2. Histological studies demonstrated that saponin did not detach endothelial cells from underlying tissues, but induced degenerative changes in the endothelial cells selectively. 3. In the cavernous strips contracted with phenylephrine, addition of acetylcholine, sodium nitroprusside, ATP and Ca2+ ionophore A23187 induced relaxations, but substance P and bradykinin did not change the muscle tone. 4. Acetylcholine-induced relaxation was significantly attenuated but not abolished by NG-nitro-L-arginine (L-NOARG). L-arginine restored the response inhibited by L-NOARG. The L-NOARG resistant relaxation was not influenced by 1H[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one (ODQ) but was suppressed in the strips contracted with K+. Treatment with saponin abolished the relaxation elicited by acetylcholine and A23187 but did not influence the response to nitroprusside and ATP. The ATP-induced relaxation was attenuated by aminophylline. 5. Transmural electrical stimulation at 2-20 Hz produced endothelium-independent relaxations which were abolished by tetrodotoxin and L-NOARG but unaffected by treatment with saponin. In saponin-treated cavernous strips, the neurogenic relaxation was not affected by acetylcholine, physostigmine, atropine and vasoactive intestinal peptide (VIP) but was abolished by ODQ. 6. It is concluded that acetylcholine-induced relaxations are endothelium-dependent and mediated partly by NO and also by other substances from the endothelium. The endothelium-independent relaxation to ATP is likely to be mediated by P1 purinoceptors. The function of nitrergic nerve does not seem to be prejunctionally modulated by acetylcholine and VIP.