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Y T Lin

Publications and source records attributed to Y T Lin.

At least 145 records · Page 8Linked to original sources
PubMed1983

[Immunoperoxidase staining studies on C-cells in fresh human thyroid].

It has been well demonstrated that C-cells are the source of the hypocalcemic polypeptide hormone calcitonin (CT), and that they are the origin of medullary thyroid carcinoma. However, our knowledge of the morphology of normal human C-cells is still primitive. The purpose of this study is to present a detailed report concerning the morphology, distribution and population of C-cells in fresh normal thyroid glands using the high specificity immunoperoxidase staining method. In addition, the carcinoembryonic antigen (CEA) activity in the C-cells and the solid cell nest are studied. Fifteen fresh thyroid glands with no abnormal histological or laboratory findings were examined for C-cells by Sternberger's PAP method, and five thyroid glands obtained at autopsy 6 approximately 8 hours after death with no evidence of thyroid or parathyroid disease were examined as the control group. The CEA activity in the C-cells was examined by the anti-CEA and anti-CT double staining method. The C-cells were detected in all 15 fresh glands examined. They were oval, spindle or polygonal in shape, and at the interfollicular or parafollicular position. Except for one gland which contained very rare C-cells, no C-cells were detected in the control autopsy glands. C-cells were most numerous at the junction of the upper and middle third of the lateral lobe, and in these areas the C-cell population ranged from 47 to 111 per section. Morphologically, the C-cells appeared not only singly but in groups in a parafollicular position as clusters or enclosing the follicular epithelium in the form of lamina. Solid cell nests were easily distinguished from follicular epithelium by a routine H-E staining examination. None of these areas revealed a positive reaction with anti-CT, although scattered C-cells were seen occasionally in the neighboring area. CEA activity in the C-cells was evident from the brown color by a DAB reaction product, while the CT was indicated by the violet color using a 4-chloro-naphthol reaction product. These two colors were identified in the same cells simultaneously. From these results, it is concluded: The autopsy thyroids obtained a few hours after death were not suitable for C-cell examination by the immunoperoxidase staining method. The most numerous C-cells were distributed at the junction of the upper and middle third rather than the middle third of the lateral lobe, and the population in these areas averaged from 47 to 111 per section, or about 3 times as many as reported before.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1982

Direct communication of the right pulmonary artery with the left atrium in an infant.

An 8-month-old Japanese girl with cyanosis and evidence of a round shadow connected with the right cardiac border on the chest X-ray film was diagnosed as a case of direct communication of the right pulmonary artery with the left atrium (RPA-LA communication) following cardiac catheterization and angiocardiography. She had a history of transient congestive heart failure in the early neonatal period. A secundum atrial septal defect and a two-lobed right lung were also present. The patient became asymptomatic after a successful ligation of the anomalous connecting vessel.

Adolescent↗
PubMed1980

Hemodynamic performance of the Ionescu-Shiley valve prosthesis.

The hemodynamic performance of the Ionescu-Shiley bovine heterograft valve has been evaluated by intraoperative measurement of transvalvular gradients and cardiac outputs. Effective orifice areas (EOAs) were calculated and the data compared to those obtained by other investigators for other prostheses. In the aortic position, each valve, from 19 to 31 mm external diameter, produced a pressure gradient; mean EOA increased with increasing valve size, so that small (19 to 23 mm) valves were moderately stenotic and larger valves were only mildly stenotic. The presence of a mitral prosthesis produced larger transaortic valve gradients, probably as a result of aortic outflow obstruction by the mitral prosthesis. The Ionescu valve appears to be hemodynamically superior to other biological valves in the aortic position and comparable to most mechanical prostheses, although the data for comparison are scant. Each mitral valve produced a pressure gradient and, on the average, larger (29 mm) valves performed no better than smaller (25 mm). Mean EOAs for each valve size (25 to 29 mm) were adequate to provide satisfactory hemodynamics comparable to other available prosthetic valves. Mild obstruction of the left ventricular outflow by the prosthetic struts was seen to be related to the distance between ventricular septum and the struts. Most currently available prostheses seem to provide similar hemodynamics in the mitral position, and considerations such as thrombogenicity and durability may be relatively more important in the choice of a mitral valve substitute than in the choice of an aortic valve substitute.

Aortic Valve↗
PubMed1979

beta-Blockade therapy for supraventricular tachyarrhythmias after coronary surgery: a propranolol withdrawal syndrome?

A high incidence of cardiac arrhythmias and hypertension has been noted after coronary artery bypass surgery in patients previously treated with oral propranolol. Forty-two patients undergoing coronary bypass surgery had propranolol withdrawal 10 hours before surgery and were randomized into a group treated with propranolol immediately postoperatively, and a nontreatment group. Patients treated with prophylactic propranolol had a significantly lower incidence of postoperative supraventricular arrhythmias compared to patints who received no prophylaxis. All the arrhythmias responded rapidly to 1 mg of intravenous propranolol therapy, whether it was used as a primary treatment or as a supplement to prophylactic propranolol. The findings suggest that (1) there is a high incidence of supraventricular arrhythmias and sinus tachycardia after coronary artery bypass which might reflect an abrupt propranolol withdrawal, and (2) that perioperative prophylactic or supplementary propranolol therapy will successfully prevent or treat most of these arrhythmias.

Coronary Artery Bypass↗
PubMed1979

Arterial hypoxemia in patients with anterior and posterior nasal packings.

Previous clinical reports indicate that nasal packing is frequently associated with arterial hypoxemia. Anesthesia and surgery in hypoxemic patients can be hazardous, especially when it is associated with acute blood loss. Nine patients with severe epistaxis, who failed to respond to anterior and posterior nasal packing, were anesthetized for emergency internal maxillary artery ligation. Arterial blood-gas and pH changes during the procedure were evaluated. The results indicate some degree of arterial hypoxemia and high alveolar/arterial PO2 difference without significant change in PaCO2 and pH in most of the patients observed. Arterial PO2 was within normal range 24 hours after operation. The anesthetic management is described and the various causes of such arterial hypoxemia are reviewed. It is important to recognize the presence of arterial hypoxemia and treat accordingly during surgery for such patients.

Adult↗
PubMed1976

Xf phage invading the host cells with their protein coats.

The Xf phage coat protein associated with infected cells could not be removed by washing with antiserum and tris-EDTA buffer. Although the infected cells were consecutively washed 6 times with tris-EDTA buffer, the ratios of parental phage 6H-DNA to 14C-protein were not changed. A considerable amount of the parental 14C-protein and 3H-DNA in the original ratio were detected in the membrane and the soluble cytoplasmic fractions of infected cells. The studies of the change in Xf 14C-protein and 3H-DNA incorporation into the host cells and their release showed that DNA and protein penetrate together into the host cells during the first 60 min after infection (p.i.). While virtually all parental DNA was conserved, re-utilized and released from the infected cell 60 min p.i., no apparent release of parental protein was observed. Approx. 40% of the parental protein became degraded and could be washed from the infected cell after 90 min; the rest of the parental protein remained and probably was re-utilized by the host.

Bacteriophages↗