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OBJECTIVES: To assess the performance of interferon-gamma release assays (IGRAs) in the differential diagnosis between Mycobacterium avium complex (MAC) and tuberculosis (TB) in children affected with subacute/chronic submandibular/cervical lymphadenitis. STUDY DESIGN: Multicenter observational study comparing children with microbiologically confirmed MAC lymphadenitis from the European NontuberculouS MycoBacterial Lymphadenitis in childrEn study with children with TB lymphadenitis from the Spanish Network for the Study of Pediatric TB database. RESULTS: Overall, 78 patients with MAC and 34 with TB lymphadenitis were included. Among MAC cases, 44 out of 74 (59.5%) had positive tuberculin skin test (TST) results at the 5-mm cut-off, compared with 32 out of 33 (97%) TB cases (P

Familial defective apolipoprotein B-100 (FDB) is a genetic disorder resulting from a mutation in the apolipoprotein B-100 (apo B-100) gene, most frequently at position 3500, in which arginine is substituted for glutamine in the mature protein. This mutation drastically decreases the affinity of the mutant apo B-100 particle for the low-density lipoprotein (LDL) receptor, and hence decreases the clearance of cholesterol from the circulation. Familial hypercholesterolemia (FH), also a disorder of lipid metabolism, results from mutations in the gene for the LDL receptor. Both FDB and heterozygous FH occur at approximately the same frequency (1 in 500) among Caucasians and both produce clinical symptoms and signs that can be indistinguishable. Polymerase chain reaction (PCR) amplification and subsequent restriction analysis have been used to detect the substitution at codon 3500 in the apo B-100 gene using mutagenic PCR primers. At least one proband from 10 unrelated families with a history of hypercholesterolemia was screened by mutagenic PCR for FDB. Only one of 10 patients demonstrated the mutation for FDB. The mutant apo B-100 allele was shown to segregate with other clinically affected family members. These results demonstrate that molecular analysis is essential to distinguish between FDB and heterozygous FH in hypercholesterolemic families.

The DANTE pulse sequence was modified to produce selective resonance saturation similar to that produced by the continuous wave (CW) technique. A combined DANTE and CW saturation technique can be used to perform multisite saturation transfer experiments because of the similar saturation produced by the two techniques. © 1991 Academic Press, Inc.

Objective: Apolipoprotein E (APOE) E4, apolipoprotein B-100 (APOB) Q3611 allele, the angiotensin converting enzyme (ACE) deletion (D) allele and glycoprotein IIIa (GP3A) P33 mutant allele are reported to predispose to early-onset coronary heart disease (CHD). These associations were not all confirmed in more recent studies. To determine the impact of these alleles on CHD, we examined the prevalence of these mutations in patients presenting with early-onset CHD and compared them to those manifesting CHD later in life. The delayed-onset was considered a sign of longevity and would serve as a comparative group to assess prevalence of the biochemical and genetic risk factors. Methods: 300 patients with a history of myocardial infarction or angina pectoris and angiographically documented CHD were studied. Patients were divided into two groups: group 1 (G1 = 150 patients) presenting with these findings under the age of 50 years; while group 2 (G2 = 150 patients) were patients presenting for the first time over the age of 65 years. Prevalence of the alleles of APOE, APOB, ACE and GP3A was assessed by molecular analysis. An association of any of these genotypes with early onset CHD could lead to a higher prevalence in the younger age group. Results and Conclusions: None of the suspected alleles namely APOB Q3611 [G1: 10.7% vs. G2: 9.0%, p = 0.57], ACE D (G1: 52.0% vs. G2: 49.7%, p = 0.57), or the GP3A P33 (G1: 17.3% vs. G2: 15.7%; p = 0.58) showed any significant difference between the two groups. Subjects with APOE E4 were more frequent in the younger age group (G1: 18.3% vs. G2: 13.7%; p = 0.047), while APOE E2 was more frequent in G2 (G2: 10.0% vs. G1: 2.7%; p = 0.0002). Multivariate analysis showed an odds ratio of APOE E2 allele in G1 of 0.27 with a confidence interval of 0.10–0.73.

Objective: In the presence of low serum folate, mutant 5,10-methylenetetrahydrofolate reductase (MTHFR+ [A223V/C677T]) in the homozygous state (+/+), may predispose to higher plasma homocysteine (tHct) levels and coronary artery disease (CAD). To determine the impact of this relationship on predisposition to early-onset CAD, we examined the prevalence of the mutation and plasma tHct in patients with early-onset CAD and compared them to patients manifesting CAD later in life. Methods: Three hundred patients with history of acute myocardial infarction or angina pectoris and angiographically documented CAD were studied. Patients consisted of two groups: group 1 (G1 = 150 patients) presenting with these findings under age 50; while group 2 (G2 = 150) presented for the first time over age 65 years. Prevalence of the MTHFR+ mutation was assessed by molecular analysis, and plasma tHct and folate were measured. An association of the +/+ genotype with early onset CAD could lead to its higher prevalence in the younger age group. Results: There was no significant difference in the frequency of the (+/+) genotype between the two groups (G1: 11.3% vs. G2: 11.3%). However, patients with the (+/+) genotype in both groups had higher tHct when plasma folate was below the mean value (G1: p < 0.0001 while G2: p < 0.01). Conclusion: The mutant MTHFR genotype was not found to be a determining factor in early-onset CAD. Higher tHct values were obtained in the older age group, which is expected because other studies have shown that tHct levels increase with age. A significant relation was shown between MTHFR genotype and low folate status yielding high tHct levels in those with the (+/+) genotype. As this relation was seen in both groups, although to a lesser extent in the older G2, it does not explain the underlying cause of early-onset CAD.

Objectives: Acute intermittent porphyria (AIP) is caused by mutations in the porphobilinogen deaminase (PBGD) gene that disrupt the function of the enzyme. Many mutations that lead to decreased PBGD activity have been described. An Arg to Trp substitution at codon 173 (CGG→TGG in exon 10) and designated R173W, which leads to a CRIM-negative phenotype, has been reported in Swedish, Finnish, Scottish, and South African kindreds, and in a Nova Scotian proband with fatal AIP. In this work, we investigated the presence of this mutation in a Nova Scotian patient population presenting with AIP. Design and Methods: Single-strand conformation polymorphism analysis and DNA sequencing by TA cloning and Sanger’s dideoxy chain termination method, were used to confirm the maternal transmission of this mutation to the proband. The mutation also eliminates an NciI (also MspI) endonuclease restriction site, which allows for detection of the mutant allele by polymerase chain reaction amplification and restriction enzyme digestion. Results: The family of the Nova Scotian proband and four other AIP kindreds showed the presence of the same mutation. These five families are descendants of German, Swiss, and French immigrants historically known as the “Foreign Protestants,” who were recruited to Nova Scotia in the 1750s. Conclusion: In all these families, descent from one couple that settled in Nova Scotia in 1751 has been identified by genealogy research, consistent with a founder effect within this population. This is the first identified mutation in PBGD causing AIP that has been linked to a founder effect in descendants of an immigrant population to North America, and which could be traced to such a distant background, similar to the South African variegate porphyria mutation.

A high-precision neutron time-of-flight facility has been constructed. The facility couples the advantages of an intense monoenergetic neutron source produced by a pulsed and bunched ion beam with those of a high-energy resolution, high mechanical precision, heavily shielded neutron time-of-flight spectrometer-goniometer. The system provides the necessary incident neutron energy stability and resolution, scattered neutron energy and angular resolution, and unusual freedom from background radiations to achieve measurements of differential scattering cross sections with magnitudes as small as 1 mb/sr to better than 5% absolute accuracy. The measures required to achieve this sensitivity and accuracy include optimization of the mechanical, shielding, and electronic systems, as well as the procedures for obtaining and analyzing the data.

rECENT PROGRESS IN the physics of nuclear structure is marked by a rapid increase in the amount of new data on excited states of low‐to‐medium‐mass nuclei—those nuclei with masses roughly in the range 16⩽A⩽56. Concurrent with this worldwide experimental activity a significant increase in theoretical effort is perceptible. The attraction to this area of nuclear‐structure physics can possibly be related to the impressive array of physical phenomena that these nuclei exhibit. Very recent phenomenological developments include, for example, the frequent observation of unusual mixtures such as that of magnetic‐quadrupole and electric‐dipole multipolarities in radiative transitions between excited states and the discovery of very pure single‐particle isobaric analog states at high excitation energies. In addition, electric‐octupole transitions in direct competition with electric‐dipole and magnetic‐quadrupole transitions are becoming a persistent feature of these nuclei.

The formalism for the analysis of angular-correlation measurements of the radiative decay of aligned nuclei is expressed in a manner such as to simplify computational procedures involved in cases where several continuous parameters (multipolarity mixing ratios and population numbers or statistical tensors) and their error matrix must be determined from the experimental data. Two specific analysis procedures are presented. The discussion is based upon triple-correlation formulas which include the possibility of one or more intermediate unobserved radiations in multiple cascades. Parallel developments are presented in terms of population parameters and statistical tensors of the aligned states. It is shown that a statistical-tensor representation leads to a more elegant and convenient formulation for general multiple cascades.

$\ensuremath{\gamma}$-ray decay schemes of seven resonances in the ${\mathrm{Si}}^{29}(p, \ensuremath{\gamma}){\mathrm{P}}^{30}$ reaction in the range ${E}_{p}=700\ensuremath{-}1750$ keV have been studied in order to gain additional information on properties of resonant and bound levels of ${\mathrm{P}}^{30}$. The results also provide necessary information for the analysis of $\ensuremath{\gamma}$-ray angular-correlation and polarization measurements, which are in progress. Singles and coincidence spectra were obtained at each of the resonances at ${E}_{p}=730, 917, 1302, 1470, 1505, 1686, \mathrm{and} 1748$ keV (all\ifmmode\pm\else\textpm\fi{}2 keV) using large-volume NaI (Tl) detectors and a Ge(Li) detector. The resonance strengths were measured relative to the strength of the resonance at ${E}_{p}=416$ keV in the same reaction, which is known from previous work. Consistent resonance decay schemes were derived, along with decay schemes of lower-lying bound states which, in many cases, differ considerably from previously available information. New results, or results significantly different from earlier reports, were obtained for the decay properties of the 3.02-, 3.74-, 3.93-, 4.14-, 4.18-, 4.23-, 4.43-, 4.50-, 4.62-, and 4.92-MeV levels of ${\mathrm{P}}^{30}$. The existence of a weak transition from the ${4}^{\ensuremath{-}}$, 4.23-MeV level to the ${1}^{+}$ ground state is shown. Another unusual transition found is one from the ${3}^{\ensuremath{-}}$, 4.92-MeV level to the ${1}^{+}$, 0.709-MeV level. The energies of 17 bound levels of ${\mathrm{P}}^{30}$ were determined from the Ge(Li) data to a greater accuracy than heretofore available. Evidence is found for a previously unreported level at 4.468\ifmmode\pm\else\textpm\fi{}0.003 MeV, which is proposed to be the $J=0$, $T=1$ analog of the 3.79-MeV level of ${\mathrm{Si}}^{30}$. The decay schemes of the ${E}_{p}=730\ensuremath{-}, 917\ensuremath{-}, \mathrm{and} 1302$-keV resonances indicate they are quite pure $T=0$ levels. The new value $Q=5.597\ifmmode\pm\else\textpm\fi{}0.003$ MeV for the ${\mathrm{Si}}^{29}(p, \ensuremath{\gamma}){\mathrm{P}}^{30}$ reaction was derived from the Ge(Li) spectra.

The $\ensuremath{\gamma}$-ray decay properties of the ${J}^{\ensuremath{\pi}}$, $T={\frac{7}{2}}^{\ensuremath{-}},\frac{5}{2}$ analog of the ground state of ${\mathrm{S}}^{37}$, observed previously at ${E}_{p}=1887$ keV in the ${\mathrm{S}}^{36}(p,\ensuremath{\gamma}){\mathrm{Cl}}^{37}$ reaction, have been reexamined. Transitions to previously unobserved levels in ${\mathrm{Cl}}^{37}$ at ${E}_{x}=4.811 \mathrm{and} 5.574$ MeV were found in addition to the known strong $M1$ transition to the ${J}^{\ensuremath{\pi}}$, $T={\frac{7}{2}}^{\ensuremath{-}},\frac{3}{2}$ antianalog state at ${E}_{x}=3.105$ MeV. Other weak transitions suggest the presence of levels at ${E}_{x}=3.911 \mathrm{and} 6.482$ MeV. The data are consistent with a hypothesis that the 4.811- and 5.574-MeV levels, and possibly the other two suggested levels, are members of the group of ${\frac{7}{2}}^{\ensuremath{-}}$, $T=\frac{3}{2}$ configuration states expected from fragmentation of the antianalog state by spin and isospin recoupling of the ${{d}_{\frac{3}{2}}}^{4}$ nucleon group in $A=37$. Detailed analysis of the strengths of the analog $M1$ and Gamow-Teller $\ensuremath{\beta}$ decays to the 3.105-MeV level, and of the $M1\ensuremath{-}E2$ and $M2\ensuremath{-}E3$ mixing ratios, yields information on the wave function of the antianalog state and a prediction of the mean life of this level. A similar analysis of the ${\frac{7}{2}}^{\ensuremath{-}}$ parent, analog, and antianalog system in $A=35$ is performed and the results are presented. In both the $A=35 \mathrm{and} 37$ systems, recoupling in the ${{d}_{\frac{3}{2}}}^{n}$ nucleon group appears necessary to explain the data. Additional information on ${\mathrm{Cl}}^{37}$ levels obtained from measurements at the analog resonance, and at the ${E}_{p}=1147$-keV resonance, include the more accurate value $Q=8384.5\ifmmode\pm\else\textpm\fi{}1.5$ keV for the ${\mathrm{S}}^{36}(p,\ensuremath{\gamma}){\mathrm{Cl}}^{37}$ reaction, the energies 1.723 \ifmmode\pm\else\textpm\fi{} 0.002 and 3.1048 \ifmmode\pm\else\textpm\fi{} 0.0005 MeV for the first and third excited states, and the mean life ${\ensuremath{\tau}}_{m}={0.17}_{\ensuremath{-}0.05}^{+0.09} \mathrm{and} g~1.0$ psec for the 1.723- and 3.105-MeV levels, respectively. The results of angular-correlation measurements at the 1147-keV resonance are consistent with earlier assignments of $J=\frac{1}{2}$ for the 1.723-MeV level. The results are compared with recent shell-model calculations involving ${{d}_{\frac{3}{2}}}^{n}{f}_{\frac{7}{2}}$ and ${{d}_{\frac{3}{2}}}^{n}{p}_{\frac{3}{2}}$ configurations. The observed $M2$ transition rates are successfully explained using bare-nucleon $g$ factors when recoupling of the ${{d}_{\frac{3}{2}}}^{n}$ group is considered.

Basic formulas and tabulations of numerical coefficients are provided for the analysis of data on angular correlations of successive radiative transitions from aligned nuclei. The formulas are extracted from an earlier published development of the angular-correlation formalism. This development is based upon a factored version of the equations which is used to extend the application from the usual two-step cascade to general multiple-step cascades. The resulting flexibility and greater efficiency of the formalism are utilized to provide an extensive tabulation of coefficients for a variety of specific applications. Coefficients are provided for analysis in terms of either the population parameters or the statistical tensors of the aligned state. The coefficients can be used for the analysis of angular distributions, linear polarizations, and triple correlations involving one or more intermediate unobserved radiations. In contrast to previous tabulations of coeeficients for angular-correlation analysis, the range of the present tables has been extended to include multipolarities through octupole. The overall length of the tables, however, remains about the same as previous tables because of the greater efficiency of the factored formalism. The range of spins covered by the tables are J ≤ 11/2 for the initial aligned stae and J ≤ 21/2 formore » the final state of cascade.« less

Angular distributions and triple correlations of gamma rays emitted from several resonances in the range E/sub p/ = 1177 to 1509 kev in the Si/sup 30/(p, gamma )P/sup 31/ reaction were measured using thin, highly enriched Si/sup 30/ targets. The angular distributions and correlations lead to the resonance level assignments 1177(7/2), 1204(5/2), 1324(5/2), 1392(5/2), 1400(3/2), are in kev. The results indicate even parity for all of the resonances if it is assumed that all gamma-ray multipolarity mixings are of the form E(L + 1)/M(L). The mixing ratios are presented for most of the observed primary transitions and of several secondary transitions. The results of this study are consistent with the assignments 3.41-Mev level is identified as 7/2+ by means of angulardistribution and correlation measurements at the 1509-kev resonance. A 7/2+ assignment for the 3.41-Mev level casts doubt upon the existence of a weak transition from that level to the 1/2+ ground state. Results of several measurements designed to determine the origin of the weak gammaray peak of approximately 3.4 Mev in coincidence spectra at the 1509-kev resonance were inconclusive. Angular distributions at the 1204-kev resonance lead to the assignment of 3/2+ to the 4.26-Mev level. Limitations are placed on themore » possible assignments for the 4.43 and 5.01-Mev levels. Both members of the doublet near E/sub p/ = 1481 kev are found to decay mainly to the ground state and each have J = 3/2 on the basis of anguiar distributions. The value of GAMMA /sub p/ GAMMA /sub gamma / GAMMA / sub t/ was determined for each of the resonances. Results of this study are discussed in terms of recent collective model calculations for P/sup 31/. (auth)« less

The gamma -ray yield curve was observed when thin targets of natural silicon were bombarded with monoergic protons in the energy range of 300 to 1840 kev. In order to take small steps in proton energy, a target potential modulation technique was used. Fifty-five resonances were observed, all but fifteen of which were obsemved elsewhere using targets enriched in Si/sup 29/ or Si/sup >0/. The fifteen resonances at 369, Si/sup 28/ + p reaction. (auth)

We have discussed alternative diagnostic strategies in patients with potential or established cerebral metastases prior to the initiation of steroid and radiotherapy. This approach is based upon the potential information content that can be attained from alternative diagnostic techniques in the face of a spectrum of clinical symptoms. There is obvious need for more research on the relative merits of alternative approaches to these patients. These data could perhaps best be attained by developing a research protocol which is designed to measure the information content of alternative diagnostic techniques when different spectra of clinical symptoms are present. We should seek to increase the yield of a diagnostic technique and thus allow for more specific approaches to different constellations of clinical attributes.

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A physiologically acceptable solution of tantalum-178 having an activity of 0.1 to 200 millicuries per milliliter of tantalum-178 solution is provided. The solution is obtained from tungsten-178 bound to a column of an anion exchange resin which forms tantalum-178 in situ by eluting the column with a hydrochloric acid solution containing hydrogen peroxide to form an acidic solution of tantalum-178. The acidic solution of tantalum-178 then is neutralized.