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J S Tang

Publications and source records attributed to J S Tang.

At least 37 records · Page 2Linked to original sources
PubMed1995

Isolated resection of proper caudate lobe for hepatocellular carcinoma in cirrhotic liver: a case report.

The caudate lobe of the liver is located between the hepatic hilum and the inferior vena cava. Resection of the caudate lobe alone, without sacrificing other parts of the liver, is a surgical challenge. An isolated resection of proper caudate lobe was accomplished here in a 64-year-old man with hepatocellular carcinoma complicated by liver cirrhosis. The post-operative course was uneventful. The patient remains free of disease two years after operation. The technique used is described to advocate isolated caudate lobectomy for a patient with cirrhosis with a caudate lobe hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1995

[The roles of thalamic nucleus submedius in nociception and pain modulation].

Recent studies on the roles of thalamic nucleus submedius (Sm) in nociception and pain modulation were reviewed in this article in combination with own our works. Results of these studies showed that Sm may be involved in effective-motivational aspects of pain, and that Sm-VLO-PAG may constitute a pathway of nociceptive modulation which may depress the nociceptive inputs at the spinal cord level via the brain-stem descending inhibitory system, thereby mediate a negative feedback regulation of pain.

Animals↗
PubMed1994

A newly developed serum-free culture system: clonal growth of human acute myelogeneous leukemia (AML) progenitors--a report of 14 AML cases.

A new serum-free culture (SFC) system for human AML-CFU was established and the colony-promoting activity of four recombinant human hematopoietic growth factors (rhHGFs) including granulocyte-macrophage colony-stimulating factor (rhGM-CSF), interleukin-3 (rhIL-3), erythropoietin (rhEPO) and newly developed stem cell factor (rhSCF) were investigated in this SFC system. Under the orthogonal design condition, it was found that human AML-CFU presented optimal clonal growth in an environment of bovine serum albumin (0.6%), saturated human transferrin (2 x 10(-6) mol/L), cholesterol (2.8 micrograms/ml), bovine insulin (15 micrograms/ml), bovine hemin (0.05 mmol/L), linoleic acid (2.8 micrograms/ml), and IMDM. Spontaneously growing colonies were observed in 11 out of 14 cases studied. The plating efficiencies obtained by culturing with rhGM-CSF, rhIL-3, and rhSCF were 0.776 +/- 0.621%, 0.574 +/- 0.510%, and 0.647 +/- 0.543% (mean +/- s), respectively. There was one case (M3b) showing no response to all HGFs in both SFC ad SCC. The clonal growth of AML-CFU obtained from peripheral blood of the patient with M6 was unexpectedly marked. As a whole, the newly designed SFC system has been demonstrated to be useful for culture of human AML-CFU from both bone marrow and peripheral blood.

Culture Media, Serum-Free↗
PubMed1994

An effective method for depleting mature T lymphocytes from bone marrow cells--two-step Percoll centrifugation.

In the present paper we have observed the effect of discontinuous gradient two-step Percoll centrifugation on depleting mature T lymphocytes from normal bone marrow. The pre-/post-Percoll percentage of CD34+, and Leu4+ cells in MNC was counted by using APAAP technique. As the two-step Percoll centrifugation is simple, and time saving, and decreases the incidence of contamination of cultured cells as well, This technique may be of value in serum-free culture of hematopoietic cells and immunological studies.

Antigens, CD↗
PubMed1994

[Effect of recombinant human stem cell factor (rhSCF) on self-renewal of stem/progenitor cells of human acute myelogenous leukemia].

Using serum-free culture system and liquid/semi-solid dual culture technique, we examined the effect of rhSCF on self-renewal of the stem/progenitor cells of human acute myelogenous leukemia (AML-CFU). The results revealed that the rhSCF as a hematopoietic growth factor (HGF) exerted its effect hierarchically earlier than interleukin-3 and granulocyte/macrophage colony-stimulating factor on AML-CFU. rhSCF, whether used alone or in combination with other HGFs, showed potential maintenance of self-renewal of AML-CFU in most AML patients studied. However, considerable discrepancy existed in maintenance among various FAB types of patients or even in patients with the same FAB type. It is suggested that SCF may play an important role in the pathological development of AML.

Adolescent↗
PubMed1994

Growth and metabolism of cultured bone cells using microcarrier and monolayer techniques.

The traditional in vitro cell culture methods provide bone cells on matrix-coated Petri dishes to grow the cells in a monolayer. This limits the usefulness in situations where there is a need to suspend anchorage dependent cells. To promote the massive production of the cultured cells and to enable the suspension of the cells in a medium, microcarrier cell culture was developed and evaluated. Isolated bone cells from rat calvaria were incubated in a microcarrier culture flask with Cytodex 1. The microcarrier cell morphology was examined by a phase contrast microscope, a scanning electron microscope, and a transmission electron microscope. Cell growth, enzyme markers, and biosynthetic characteristics were examined and compared for microcarrier and monolayer methods. The results indicate that all the characteristics of the bone cells, whether cultured in the Petri dish or microcarrier, were the same. Therefore, the studies of the function and behavior of bone cells still remain useful using the microcarrier system culture.

Alkaline Phosphatase↗
PubMed1993

Responses of neurons in the rat thalamic nucleus submedius to cutaneous, muscle and visceral nociceptive stimuli.

The findings of recent studies have suggested that nucleus submedius (Sm) may be an important thalamic relay for nociceptive information. The aim of the present electrophysiological study was to examine in greater detail the activity and response properties of neurons in the rat Sm in order to further evaluate this hypothesis. Single unit extracellular recordings from neurons histologically verified to be in Sm were obtained in urethane/chloralose-anesthetized rats. Noxious but not innocuous mechanical stimulation elicited responses in 75% of the 204 neurons studied. Most (85%) of these neurons were excited, 10% were inhibited and a few neurons (5%) were excited by stimulation at some sites on the body and inhibited from other sites. The receptive fields were usually very large and bilateral. No marked differences were observed in the incidence, response type, or spontaneous activity of neurons located in dorsal, ventral, rostral or caudal parts of Sm. Most of these neurons (99 of 108, 92%) also responded to noxious heating and had a mean threshold of 47 degrees C. The majority of the neurons (19 of 21, 90%) also responded to subcutaneous, intramuscular or intraperitoneal injections of noxious chemicals (formalin or hypertonic saline). The responses elicited by pinching skin or squeezing muscle were frequently facilitated by the subcutaneous or intramuscular injections of formalin. Single electrical stimuli delivered to the cutaneous receptive field rarely produced responses. However, short trains (15-25 msec trains of 200 Hz, 3 msec pulses at 5-10 mA) delivered repetitively elicited responses in 90% (n = 73) of the neurons. These responses appearing after repetitive stimulation frequently resembled the 'wind-up' pattern observed in spinal cord dorsal horn. The conduction velocities of the primary afferents which elicited the Sm neuronal responses as estimated from the latency differences of responses elicited by stimulation at two points along the tail, were indicative of recruitment of A delta and C fibers. These findings provide further support for the proposed role of Sm in thalamic nociceptive mechanisms.

Animals↗
PubMed1993

Effect of systemic morphine on neurons in the lateral reticular nucleus area of the rat.

The present study is undertaken to investigate the effect of systemic morphine on neurons in the lateral reticular nucleus (LRN) using extracellular recording techniques. The spontaneous activities of 64 neurons in the LRN area were tested with morphine (3-5 mg/kg, IV). Morphine excited 23 and inhibited 28 neurons tested, and 13 neurons were not affected. Of the 28 neurons inhibited, 20 were identified as nociceptive and the remaining 6 were nonnociceptive. Of the 23 neurons excited by morphine, 18 were nociceptive and 5 were nonociceptive. Systemic naloxone (0.3-0.5 mg/kg) significantly reversed the morphine effect in 15 out of 19 neurons excited and 19 out of 20 neurons inhibited by morphine. Thirteen out of 64 neurons were further identified as reticulospinal neurons, of which four were excited and four were inhibited by morphine. The remaining five were not affected. The results demonstrate that a similar proportion of neurons in the LRN area were either excited or inhibited by systemic morphine, and the majority of them are nociceptive neurons. It is suggested that different types of neurons in the LRN area may have different functions in morphine analgesia.

Animals↗
PubMed1993

Spontaneous rupture of splenic hemangioma: a case report.

Splenic hemangioma is rare. The major problem concerning splenic hemangioma is the difficulty of preoperative diagnosis. No characteristic signs allow the specific diagnosis of this tumor. Spontaneous rupture is the main complication, occurring in up to 25% of cases reported. In cases of rupture of the tumor, splenectomy is a life-saving and mandatory procedure. A case of spontaneous rupture of splenic cavernous hemangioma is presented and the literature is reviewed.

Adult↗
PubMed1990

Responses of reticulospinal neurons in the lateral reticular nucleus area of the rat to cutaneous noxious and non-noxious stimulation.

Response properties of reticulospinal neurons in the lateral reticular nucleus (LRN) area to natural cutaneous stimulation were investigated systematically in 45 urethane-anesthetized rats by using extracellular recording techniques. A total of 64 neurons were tested with peripheral stimuli, of which 19 were responsive only to noxious stimuli; 7 responsive to both noxious and non-noxious stimuli; 4 responsive only to non-noxious stimuli; and 34 not responsive to any cutaneous stimuli. Both the noxious and non-noxious receptive fields were large and bilateral. Among the neurons responding to noxious stimuli, the majority (72%) was excited. This study provides evidence that some reticulospinal neurons in the rat LRN area are involved in the mechanisms of nociception.

Action Potentials↗
PubMed1989

Electrophysiological identification of spinally projecting neurons in the lateral reticular nucleus of the rat.

Eighty-four neurons in the caudal ventrolateral medullary reticular formation were antidromically activated by the stimulation of the dorsolateral funiculus in 49 urethane-anesthetized rats. Of 76 neurons, 37 had no spontaneous discharge. Of the neurons that had spontaneous discharges, 80% had firing rates between 0.1 and 15 Hz. The average conduction velocity, determined among 70 neurons, was 15.20 +/- 1.23 m/s, and 87% had conduction velocities within the range of 2-30 m/s. This study further confirms the existence of spinally-projecting neurons in the lateral reticular nucleus (LRN) of the caudal medulla, and some of them are probably responsible for the descending controls of nociception from the LRN.

Action Potentials↗
PubMed1989

Functional evaluation of cultured rabbit osteoblast-like cells.

For the improvement of the adult osteoblast culture, the osteoblasts of young adult rabbit endosteal from long bones were isolated by collagenase digesting separation. 0.1% of type-I collagen precoated culture flasks were used as substrate for isolated bone cell growth. Morphological examination of cultured cells under a phase-contrast microscope, SEM and TEM observations showed a structure similar to osteoblast in vivo. Histochemical examination of alkaline phosphatase demonstrated 97% purity of cultured osteoblasts. The presence of calcium deposit activity in cultured cells was demonstrated by Van Kossa stain. High activity of alkaline phosphatase and inorganic pyrophosphatase in cultured osteoblasts as determined by biochemical analysis. High calcium uptake in cultured osteoblasts was demonstrated by radioisotope labelled 45CaCl12. According to these methods, it was indicated that the cells isolated from young rabbit long bone endosteal were osteoblast-like and still maintained their biological function. Our system for culturing osteoblast-like cells is a successful attempt in growing bone tissue in vitro starting from isolated bone cells. Therefore, this modified method for bone cell culture on collagen precoated culture flasks could be used as the experimental model in studies concerning the osteoblasts in vitro.

Alkaline Phosphatase↗
PubMed1988

Hemangiopericytoma of bone.

Primary hemangiopericytoma of bone is a rare malignant tumor. Forty-one cases from the literature were reviewed, and four additional cases are reported. The peak incidence is in fourth and fifth decades. The pelvis and lower extremities are the most common locations. The radiographic features are nonspecific, although angiography may aid in the diagnosis. Based on a limited number of evaluable cases, the prognosis seems to correlate with the histologic grade of the tumor. Late recurrence and distant metastases are common.

Adult↗
PubMed1988

Formate-nitrate respiration in Salmonella typhimurium: studies of two rha-linked fdn genes.

Localized mutagenesis was used to obtain rha-linked mutations in Salmonella typhimurium, resulting in defects in the nitrate reductase-linked formate dehydrogenase (FDHN). The fdn mutants obtained fell into two groups which differed in several respects. Group I isolates lacked FDHN activity under all conditions examined and exhibited wild-type levels of the hydrogenase-linked formate dehydrogenase (FDHH). Group II isolates appeared defective in FDHN only when freshly prepared extracts were assayed; restoration of both FDHN and formate-nitrate reduction activity occurred on incubation of extracts for 2 to 3 h. Protease inhibitors prevented restoration. Group II isolates were also characterized by a conditional FDHH activity; this activity was absent unless the growth medium designed to optimize wild-type FDHH was altered either by lowering glucose concentration or by adding thiosulfate. Cotransduction of fdn with rha ranged from 4 to 22% for the group I isolates and from 20 to 40% for the group II isolates. Temperature-sensitive isolates from both groups synthesized FDHN activity with altered thermostability. In vitro complementation occurred in mixed extracts of amber mutants of the two respective classes. The results are consistent with two distinct rha-linked fdn genes, for which we suggest using the designations fdnB (group I) and fdnC (group II).

Anaerobiosis↗
PubMed1988

Musculoskeletal infection of the extremities: evaluation with MR imaging.

Magnetic resonance (MR) imaging was performed in 17 patients, 11-84 years of age, referred for evaluation of possible osteomyelitis involving the appendicular skeleton. MR imaging permitted successful identification of osteomyelitis in ten patients (four acute, two subacute with Brodie abscess, two chronic, and two acute with septic arthritis) and of cellulitis in the absence of osteomyelitis in four patients, including one with a soft-tissue abscess. Active osteomyelitis was excluded in three patients. Both T1- and T2-weighted spin-echo sequences were needed to evaluate osteomyelitis. T2-weighted images were needed to identify foci of active infection. MR images provided more accurate and detailed information regarding the extent of involvement than did radionuclide bone scans, computed tomographic scans, or standard radiographs. It permitted the differentiation of septic arthritis or cellulitis from osteomyelitis. In this limited series, MR imaging was particularly useful for seeking foci of active infection in areas of chronic osteomyelitis complicated by surgical intervention or fracture.

Abscess↗
PubMed1986

Pseudomonas fluorescens biovar V: its resolution into distinct component groups and the relationship of these groups to other P. fluorescens biovars, to P. putida, and to psychrotrophic pseudomonads associated with food spoilage.

A numerical taxonomic analysis was performed to evaluate the appropriateness of a single biovar designation (biovar V) for all Pseudomonas fluorescens isolates negative for denitrification, levan production and phenazine pigmentation and to determine the relationship of biovar V strains to other taxa within the same Pseudomonas RNA homology group. Seventy-two strains assigned to P. fluorescens biovar V and four strains of P. fragi were characterized and the data subjected to a numerical taxonomic analysis along with comparable data for 17 previously characterized strains of this biovar and 89 P. putida strains. Seven distinct biovar V clusters containing three or more strains were revealed, and the carbon sources useful for their differentiation were identified. Cluster 1 (38 strains) closely resembled two atypical P. fluorescens I strains. It was also related to P. fluorescens biovar IV and to P. fragi. Cluster 2 (5 strains) was related to cluster 1. Cluster 3 (7 strains) was identical to a major group of meat spoilage psychrotrophic pseudomonads (P. lundensis). Cluster 4 (3 strains) was not related to any other group examined. Cluster 5 consisted of six isolates initially designated P. putida A along with four P. fluorescens biovar V strains all of which resembled P. putida more than they resembled the other P. fluorescens groups. Cluster 6 (16 strains) was distinct from the other biovar V clusters, but was closely related to P. fluorescens biovars I and II. Cluster 7 (3 strains) shared many characteristics with cluster 5. Separate P. fluorescens biovar designations are proposed for cluster 6 and for the combined clusters 1 and 2. A new P. putida biovar is proposed for the combined clusters 5 and 7.

Food Contamination↗