Comparison of Fourier and wavelet transform procedures for examining mechanomyographic and electromyographic frequency versus isokinetic torque relationships

The purpose of this study was to compare the isokinetic torque-related patterns for mechanomyographic (MMG) and electromyographic (EMG) center frequency [wavelet center frequency (CF), mean power frequency (MPF), and median frequency (MDF)] determined by the fast Fourier transform (FFT) and discrete wavelet transform (DWT). Ten adults [mean +/- SD age = 22.0 +/- 3.4 yrs] performed submaximal to maximal, isokinetic muscle actions of the biceps brachii on a Cybex II dynamometer. For both MMG and EMG, the CF, MPF, and MDF values were intercorrelated at (r = 0.91-0.98). Quadratic models provided the best fit for the absolute and normalized CF, MPF, and MDF versus isokinetic torque relationships for MMG (R2 = 0.67-0.83) and EMG (R2 = 0.72-0.90). The similarities among the CF, MPF, and MDF patterns suggested that Fourier or wavelet transform procedures can be used to examine the patterns of MMG and EMG responses during dynamic muscle actions.     

Idiotypic and fine specificity analysis of a (4-hydroxy-3-nitrophenyl)acetyl (NP)-specific suppressor T cell hybridoma at the level of cell surface structures, isolated receptor material and functional suppressor factor

The (4-hydroxy-3-nitrophenyl)acetyl (NP)-specific T suppressor cell hybridoma 7C3-13 was established by fusing splenic B10.BR T cells enriched on NP-coated petri dishes with the AKR thymoma BW5147. 7C3-13 was selected by anti-NPb idiotypic and anti-I-Jk antibodies in microcytotoxicity tests. The hybridoma expressed H-2k, I-Jk, Qa-1, Thy-1.1 as well as idiotypic (binding site-related) and framework Ig VH determinants, while it was negative for I-A, I-E/C, Thy-1.2, Lyt-1, Lyt-2 and Ig constant region determinants. Hapten-binding receptor material could be isolated from 7C3-13 cells on NP-coupled nylon nets and functionally active T suppressor factor (TsF) could be extracted from the hybridoma. Both types of soluble molecules express NPb idiotype, but the TsF carries I-J determinants in addition while the isolated receptors do not. The molecular weight of the isolated receptor material is 80 000, that of the TsF activity is 27 000 and 57 000-64 000, respectively. We thus were able to show that NP-binding molecules can be obtained in the form of cellular surface receptors, isolated receptor material and extracted TsF from one and the same, monoclonal, cell source.     

Leydig-cell function in children after direct testicular irradiation for acute lymphoblastic leukemia

To assess the effect of testicular irradiation on testicular endocrine function, we studied 12 boys with acute lymphoblastic leukemia who had been treated with direct testicular irradiation 10 months to 8 1/2 years earlier. Insufficient Leydig-cell function, manifested by a low response of plasma testosterone to chorionic gonadotropin or an increased basal level of plasma luteinizing hormone (or both), was observed in 10 patients, 7 of whom were pubertal. Two of these patients had a compensated testicular endocrine insufficiency with only high plasma concentrations of luteinizing hormone. Testosterone secretion was severely impaired in three pubertal boys studied more than four years after testicular irradiation. A diminished testicular volume indicating tubular atrophy was found in all pubertal patients, including three who had not received cyclophosphamide or cytarabine. These data indicate that testosterone insufficiency is a frequent complication of testicular irradiation, although some patients continue to have Leydig-cell activity for several years after therapy.     

Isolated hapten-binding receptors of sensitized lymphocytes. V. Cellular origin of receptor molecules

Chimeric mice were constructed by injection of thymus cells into nu/nu mice. The thymus cells carried a different immunoglobulin (Ig) heavy chain linkage group than the cells of the recipients. The chimeric animals were then immunized with the hapten (4-hydroxy-3-nitro-phenyl)acetyl (NP) on an appropriate carrier, and NP-binding receptor molecules were isolated from the spleen cells of the animals. Receptor molecules and antibodies were analyzed for the presence of two Ig heavy chain variable region (V_H) markers which are specific for the anti-NP response of mice carrying the Ig^b allogroup, namely the NP^b idiotpye and the heteroclitic fine specificity of hapten binding. Two types of receptor molecules are obtained by our method, those carrying determinants of Ig constant domains (anti-Ig⁺ receptors) and others lacking such determinants (anti-Ig^? receptors). The two V_H region markers were found on anti-Ig^? receptors but not on anti-Ig⁺ receptors and humoral antibodies when the T cells in the chimeric mice carried the Ig^b allogroup, whereas the B cells were Ig^a/a. Conversely, anti-Ig⁺ receptors and humoral antibodies but not anti-Ig^?receptors, expressed the two markers when the B cells of the chimeras carried the Ig^band the T cells the Ig^a allogroup. From these results and previous data showing that anti-Ig^? receptors are enriched together with T lymphocytes and anti-Ig⁺ receptors together with B cells, we conclude that the V_H-bearing anti-Ig^? receptors are not only present on T cells, but are indeed synthesized by these cells.     

Hidradenoma of the skin. Synoptic reveiw of syringeal hidradenoma, eccrine epithelioma and eccrine basalioma (author's transl)]

An ulcerating and sclerosing skin tumour on the temporal forehead region is described. Histologically the tumour is composed of different structures as cystic hidradenoma, syringoma, ductal hidradenoma and sclerres as cystic hidradenoma, syringoma, ductal hidradenoma and sclerosing basalioma arranged in layers. The tumour appears to be a distinct and diagnosable entity. It exists a major similarity to such tumours reported as syringeal hidradenoma, eccrine epithelioma or eccrine basalioma.     

Reconstitution of genetically regulated responses against random and ordered synthetic polypeptides by methylated bovine serum albumin as analyzed by isoelectric focusing.

In previous publications it was shown by avidity measurements, cross-reactivity patterns and genetic analyses, that the tetrapeptide T-T-G-G is the immuno-dominant epitope of the synthetic polypeptide (T, G)-A--L. In the present study this close immunological relationship between the random multichain copolymer (T, G)-A--L and the ordered analogue (T-T-G-G)-A--L is extended by two additional criteria. First, the immune response against (T-T-G-G)-A--L in H-2k nonresponder mouse strains can be reconstituted to high antibody levels by complexing this antigen to methylated bovine serum albumin, as was tested earlier for (T,G)-A--L. The antibodies elicited upon reconstitution in both antigenic systems are directed mainly against the same determinant, T-T-G-G. Second, isoelectric focusing analysis of specific antisera developed with radiolabeled antigen revealed restricted 7 S IgG antibody populations in high responder and reconstituted high and low responder mice. The spectra were found to be of similar complexity in the (T,G)-A--L and in the (T-T-G-G)-A--L system. From these data it was concluded that the repertoires of specific B cells to T-T-G-G are very similar in high and low responder strains, and the defect in the H-2k low responder systems should be located at the level of T-B cell cooperation.     

The spectrum of renal disease in Laurence-Moon-Biedl syndrome

To determine the nature, extent, and severity of renal involvement in Laurence-Moon-Biedl syndrome (obesity, mental retardation, polydactyly, hypogonadism, and pigmented retinal dystrophy), we evaluated 20 of 30 patients with the disorder identified from ophthalmologic records in Newfoundland. The mean age was 31 years, and seven were male. All 20 patients had structural or functional abnormalities of the kidneys or both. Three had end-stage renal disease, with two requiring maintenance hemodialysis. The remaining 17 patients had normal serum creatinine values and estimated creatinine clearances. Half the subjects had hypertension. Fourteen of 17 patients could not concentrate urine above 750 mOsm per kilogram of body weight even after vasopressin, whereas all 10 normal controls could. Urinary pH decreased below 5.3 after ammonium chloride administration in all 15 normal controls, but in only 13 of 18 patients. Calyceal clubbing or blunting was evident in 18 of 19 patients studied by intravenous pyelography; 13 patients had calyceal cysts or diverticula. Seventeen of 19 patients had lobulated renal outlines of the fetal type. Four patients had diffuse renal cortical loss, but only two of these had renal insufficiency. We conclude that Laurence-Moon-Biedl syndrome includes the presence of renal abnormalities.     

Molecular size distribution of somatostatin-like immunoreactivity in the cerebroventricular fluid of neurosurgical patients

The molecular size distribution of somatostatin-like immunoreactivity (SLI) in the cerebroventricular fluid of patients with Parkinson's disease, dystonic syndromes, multiple sclerosis, basal and midline tumors, epilepsy and pain syndromes was investigated by separation with a Sephadex G-50f column and subsequent radioimmunoassay of the eluate. Marked heterogeneity of SLI was observed in most of the pools investigated. The most conspicuous feature of the elution profiles was the preponderance of the peak coeluting with synthetic somatostatin-14, whereas the peaks comigrating with synthetic somatostatin-28 and attributable to precursor-like SLI represented only minor or trace amounts of total immunoreactivity. These findings are consistent with the greater biological activity of somatostatin-14 in the human central nervous system, whereas somatostatin-28 appears to represent the more active form in the pituitary and in the intestinal mucosa. Solely in the case of brain tumor patients, some differences could be seen, resulting in an approximately equal distribution of somatostatin-14 and somatostatin-28 in two pools of ventricular fluid and by the detection of a degradation product of somatostatin-14 in another one. These observations could be explained by a lowered barrier function as a consequence of increased intracranial pressure in case of brain tumors, which is well in accordance with a markedly elevated total protein content being a sign of a lowered barrier function.     

Fusion of freehand SPECT and ultrasound: First experience in preoperative localization of sentinel lymph nodes

Purpose

Radioguided sentinel lymph node biopsy (SLNB) is the standard of care in breast cancer and melanoma. Additional preoperative Single-photon emission computed tomography (SPECT/CT) for improved anatomical co-registration of the SLNs causes additional radiation exposure and is time-consuming and expensive. The aim of this prospective study was to evaluate a novel approach involving real-time fusion of freehand SPECT (fhSPECT) and ultrasound (US) for anatomical co-registration of SLNs.

Methods

From February 2015 to February 2016, 153 patients were included in this prospective study. All patients underwent lymphoscintigraphy according to practical guidelines and 151 (118 cases of breast cancer, 30 cutaneous malignancies, and three cases of vulvar cancer) of the 153 patients were additionally investigated with fhSPECT-US. FhSPECT connected to a hand-held gamma detector generates three-dimensional images of the radioactivity distribution in the scanned area. For co-registration and real-time fusion of fhSPECT and subsequently performed US, an infrared stereo tracking system was used.

Results

In all patients an SLN was found on lymphoscintigraphy, and the fhSPECT detected corresponding hotspots in all but one patient. In 72 % of patients and 73 % of lymph node basins, real-time anatomical co-registration with US was feasible. The rate of success in achieving good co-registration increased from 60 to 75 % after training by a radiologist specialized in breast imaging. A higher co-registration rate (78 %) was observed in patients with only one SLN than in those with two SLNs (68 %) or three or more SLNs (0 %).

Conclusions

Real-time fusion of fhSPECT and US for preoperative anatomical co-registration of SLNs is feasible. However, before this approach can completely replace preoperative lymphatic imaging, further technical developments are needed.