J chain-positive cells in bursectomized chicks

Using embryonic chickens treated with testosterone propionate, the effects of congenital absence of the bursa of Fabricius determined by the frequency of J chain-positive cells was examined in the spleen, thymus and bone marrow at the embryonic and newly hatched stages. J chain-positive cells in the chicks without bursa were reduced in the spleen. No differences in the numbers of the cells were detected in the thymus and bone marrow. These results imply that removal of the bursa of Fabricius cannot entirely prevent the generation of J chain-positive B cells. Furthermore, these results partly suggest the important role of the bone marrow in the proliferation of some J chain-positive cells in chicks without bursa.     

Continuous estimation of systolic blood pressure using the pulse arrival time and intermittent calibration

A continuous noninvasive method of systolic blood pressure estimation is described. Systolic blood pressure is estimated by combining two separately obtained components: a higher frequency component obtained by extracting a specific frequency band of pulse arrival time and a lower frequency component obtained from the intermittently acquired systolic blood pressure measurements with an auscultatory or oscillometric system. The pulse arrival time was determined by the time interval from QRS apex in electrocardiogram to the onset of photoplethysmogram in a fingertip beat-by-beat via an oximetric sensor. The method was examined in 20 patients during cardiovascular surgery. The estimated values of systolic blood pressure were compared with those measured invasively using a radial arterial catheter. The results showed that the correlation coefficients between estimated values and invasively obtained systolic blood pressure reached 0.97±0.02 (mean±SD), and the error remained within ±10% in 97.8% of the monitoring period. By using a system with automatic cuff inflation and deflation to acquire intermittent systolic blood pressure values, this method can be applicable for the continuous noninvasive monitoring of systolic blood pressure.     

Balanced complex rearrangement involving chromosomes 8, 9, and 12 in a normal mother,derivative chromosome 9 with recombinant chromosome 12 in her daughter with minor anomalies

We report on a 19-month-old girl with a derivative chromosome 9 and a recombinant chromosome 12 resulting from a maternal balanced complex rearrangement involving chromosomes 8, 9, and 12. The karyotype of the phenotypically normal mother was 46,XX,t(8;12) (9;12) (8qter→8p23::12q12→12q15::9q32→9qter;9pter→9q32::12q15→12qter;12pter→12q12::8p23→8pter). The child's karyotype was 46,XX,?9,?12, +der(9) (9pter→9q32::12q15→12qter),+rec(12) (12pter→12q15::9q32→9qter) mat. The child had severe growth retardation, minor anomalies including trigonocephaly, hypertelorism, broad nasal root, apparently low-set and posteriorly angulated ears, triangular face, pectus carinatum, clinodactyly of fifth fingers, and almost normal psychomotor development. To the best of our knowledge, there have been only 3 previous reports of recombination derived from parental complex chromosome rearrangements. In the recombination products, the chromosomes were apparently balanced and the offspring had no clinical abnormalities. The present case exhibited abnormalities and may have a submicroscopic aberration of 12q arising from crossing over during maternal meiotic pairing, although her chromosomes appeared to be balanced. © 1993 Wiley-Liss, Inc.     

Blood coagulation and fibrinolysis in patients with Beh?et's disease

In patients with Beh?et's disease, venous thrombosis has often been described as a complication. The pathogenesis of this complication, however, has not been fully understood. In this work, various parameters of blood coagulation and fibrinolysis were studied in 20 patients with Beh?et's disease and 13 sex-matched healthy volunteers. Patients were classified into three subgroups according to the number of clinical signs involved; group I (no sign): 4 patients; group II (one or two signs): 11 patients; group III (more than three signs): 5 patients. Patients with Beh?et's disease, showed an activation of blood coagulation, such as the shortening of prothrombin time (p less than 0.001), decreases in concentrations and activities of plasma antithrombin III (AT-III) (p less than 0.01) and elevated levels of plasma thrombin-antithrombin-III complex (TAT) (p less than 0.01), compared to the control group. Plasma levels (p less than 0.01) and activities (p less than 0.01) of protein C (PC) and total protein S (PS) levels (p less than 0.05) were increased in the patients. Decreased levels of alpha 2-plasmin inhibitor (p less than 0.001) also indicated an activation of fibrinolysis in the patients. When analyzed among the subgroups, patients belong to group II and III showed higher levels of plasma FDP D-dimer (p less than 0.05) and lower levels of plasminogen (p less than 0.05), as compared with patients in group I or control group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Continuous measurements of Na, Li, and Cl in the perfused salivary gland by use of NMR

The present study was undertaken to measure tissue contents of Na, Li, and Cl non-invasively in the isolated perfused organ by nuclear magnetic resonance (NMR) using a broadband tunable probe. The NMR signals of 23Na, 7Li, and 35Cl from the isolated perfused rat mandibular gland were collected continuously and each spectrum was obtained for every 15 or 20 s. The Na concentration in the perfusate was varied by replacement with Li, and the resulting changes were monitored by measuring the signal intensities of the electrolytes. The time constant for Na exchange was slower following complete removal of extracellular Na than following its half replacement, suggesting that the Na extrusion by Na+/K+ ATPase was reduced by lowering the extracellular Na level. The time constant for Li exchange was slower than that for Na exchange. The level of Cl was nearly constant during experiment, except for a very slow increase in Cl, possibly resulting from increasing edema and/or intracellular Li storage.     

Mixed Medullary-Follicular Carcinoma of the Thyroid Immunohistochemical and Electron Microscopic Studies

A case of mixed medullary follicular carcinoma of the thyroid is reported. Grossly, the tumor was a solid, grayish white, well circumscribed mass without lymph node metastasis. Microscopically, the tumor showed both medullary and follicular areas. The follicular areas occupied discrete portions of the tumor, and were considered to be neoplastic. Tumor cells in the medullary area were polyhedral or spindle-shaped. There was no amyloid deposition within the tumor. Immunohistochemically, tumor cells in the medullary area were positive for calcitonin and negative for thyroglobulin. Some cells lining the follicles were positive for thyroglobulin. By electron microscopy, two types of tumor cell were observed. One type contained numerous cytoplasmic secretory granules, whereas the other type had few granules and showed a prominent rough endoplasmic reticulum. These findings suggested that this mixed medullary follicular carcinoma of the thyroid presented neoplastic changes within a common cell lineage.     

Three-dimensional observations of spatial arrangement of hepatic zonation and vein system in mice and house musk shrews

The three-dimensional (3D) relationship among the hepatic domains and the efferent central and afferent portal veins was investigated by macroscopy, microscopy, and computer-aided 3D reconstruction methods. To clearly distinguish the pericentral domain from the periportal, we used CCl(4)-treated mice and diabetic house musk shrews, which show typical pericentral necrosis and deposition of fat, respectively. The 3D findings obtained were verified against normal control animals using advantages of our unique observations by light and fluorescent microscopy, which made it possible to differentiate the two domains well. The pericentral domains in the mice and shrews appeared three-dimensionally as continuous branched columns, and the periportal domains exist in a sponge-like network that fills the parenchymal space among the columnar pericentral domains. The efferent central veins were concentrically surrounded by the pericentral domain, and segments of the central veins flowed into large sublobular and lobar veins. The walls of these large veins faced the pericentral domain at the confluence with the central veins; the remaining portions of the walls faced the periportal domain. The afferent portal veins were placed at the two-dimensional center of the network of the periportal domain and gave off smaller portal branches radially at the intersections of the network. Three types of liver lobules-classic, portal, and acinar-have been discussed repeatedly at the (2D) level. At the 3D level, it is reasonable to consider that the liver parenchyma consists of the two continuous domains corresponding to the distribution of the vessels that we found.     

Properties and localization of the anterior semicircular canal-activated vestibulocollic neurons in the cat

Summary Unit activites of secondary vestibular neurons that selectively responded to stimulation of the anterior semicircular canal nerve (ACN) were recorded extracellularly in the anesthetized cat. Axonal pathways and projections in the spinal cord of the ACN-activated neurons were examined by recording their antidromic responses to stimulation of the lateral and medial vestibulospinal tracts (LVST and MVST), and the bilateral neck extensor motoneuron pools in the C₁segment (C₁dorsal rami [DR] motoneuron pools). In order to determine whether the neurons had ascending axon collaterals to the extraocular motoneurons, the contralateral (c-) inferior oblique (IO) motoneuron pool was also stimulated. Twenty-seven neurons sent their axons to the ipsilateral (i-) C₁DR motoneuron pool via the LVST without any projection to the extraocular motoneuron pool. All the cells except one were located in the ventral part of the lateral vestibular nucleus. This pathway produced monosynaptic EPSPs with short time-to-peak and short half-width in C₁DR motoneurons (16/16 motoneurons). Eight neurons sent axons to the i-C₁DR motoneuron pool via the MVST without any to the extraocular motoneuron pool. Cell somata were located in the descending nucleus or in the ventral part of the lateral nucleus. These neurons did not produce postsynaptic potentials (PSPs) in any C₁DR motoneurons. All thirty-five neurons sending axons to the c-C₁DR motoneuron pool have ascending axon collaterals to the c-IO motoneuron pool.