Biomedical subjects

S J Hong

Publications and source records attributed to S J Hong.

At least 145 records · Page 8Linked to original sources

PubMed1993

Clonorchis sinensis tropomyosin: cloning and sequence of partial cDNA amplified by PCR.

C. sinensis total RNA was containing large amount of 18S rRNA but little 28S rRNA. The size of the double-stranded cDNA synthesized from poly (A)+ mRNA was 0.4-4.2 kb long with tapering upto 9.5 kb. Degenerated oligonucleotides (as 2 sense and 3 antisense primers) were designed on the conserved regions of the known tropomyosin amino acid sequences. From one out of the PCR amplifications using total cDNA and matrix of primers, a specific gene product, 580 bp in size, was produced. Upon Southern hybridization of the PCR products with Schistosoma mansoni tropomyosin (SMTM) cDNA, only one signal appeared at the band of 580 bp product. This 580 bp product was considered to encode C. sinensis tropomyosin (CSTM) and cloned in pGEM-3Zf(-) for DNA sequencing. CSTM cDNA was 575 bp containing one open reading frame of 191 predicted amino acids, which revealed 86.3% homology with SMTM and 51.1% with Trichostrongylus colubriformis tropomyosin. CSTM cDNA obtained will serve as a probe in the studies of molecular cloning of CSTM.

Amino Acid Sequence↗

PubMed1992

Inhibition by neosurugatoxin and omega-conotoxin of acetylcholine release and muscle and neuronal nicotinic receptors in mouse neuromuscular junction.

Neosurugatoxin and omega-conotoxin, known to be specific ligands for the neuronal nicotinic receptor and Ca2+ channel, respectively, were previously claimed to exert no depressant action on the mouse neuromuscular junction. It was found that in preparations partially blocked with tubocurarine or with low Ca(2+)-high Mg2+ Tyrode's, both toxins, at 3-10 microM, depressed indirect twitches and either produced wanings (neosurugatoxin) or waxings (omega-conotoxin) of indirectly elicited tetanic contractions whilst in normal Tyrode's the contractile forces were not changed. In normal Tyrode's, neosurugatoxin decreased the amplitudes of spontaneous and evoked endplate potentials and enhanced the run-down of endplate potentials as did tubocurarine though with lesser potency. By contrast, omega-conotoxin (10 microM) decreased the amplitude of the evoked but not of the spontaneous endplate potential in low Ca(2+)-high Mg2+ Tyrode's, and produced facilitation of endplate potentials, instead of run-down, on repetitive stimulations. Higher concentrations of omega-conotoxin appeared to depress quantal release in normal Tyrode's. The effects were all reversible. The prolonged endplate depolarization found in preparations treated with neostigmine or 3,4-diaminopyridine, was partially depressed by both toxins. The results suggest that neosurugatoxin blocks the neuron and muscle nicotinic receptors in the neuromuscular junction with comparable potency. The pharmacology of the nicotinic receptor on motor nerve terminal seems more similar to the muscle nicotinic receptor than to that on autonomic ganglia or brain. On the other hand, omega-conotoxin seems to block a small fraction of Ca2+ channels on the motor nerve and decreases the quantal release of evoked endplate potentials.

Acetylcholine↗

PubMed1992

[Comparative study on the effectiveness of modified Kato's cellophane thick smear and Stoll's dilution egg counting technique for quantitative fecal examination of helminth eggs].

A total of 197 fecal specimens was prepared for quantitative examination of helminth eggs by modified Kato's cellophane thick smear (M.C.T.S.) and Stoll's dilution egg counting technique (D.E.C.T.). The comparative effectiveness of two techniques was evaluated and conversion function was deduced. The average time required for the microscopic examination on one slide by M.C.T.S. was 12.6 minutes and that of D.E.C.T. was 14.6 minutes. M.C.T.S. showed lower false negative rate than D.E.C.T. in light worm burden cases. Functions to convert the counts obtained by M.C.T.S. to E.P.G. by Stoll's dilution egg counting technique were 47.86 x 10(0.87) logM.C.T.S. in A. lumbricoides, 41.69 x 10(0.82) logM.C.T.S. in T. trichiura and 63.10 x 10(0.85) logM.C.T.S. in C. sinensis. It was suggested M.C.T.S. be better than D.E.C.T. for the quantitative examination of intestinal helminthiases such as A. lumbricoides, T. trichiura, and C. sinensis infections even in the cases with low worm burden.

Cellophane↗

PubMed1992

Surface ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae).

The surface ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae) was studied by scanning electron microscopy(SEM). The adult worms were recovered from experimentally infected cats and from a naturally infected patient. They were leaf-like, ventrally concave, and ovoid or pyriform in shape. Ciliated knob-like sensory papillae (type I) were observed in single or grouped forms on and around the oral sucker, whereas non-ciliated round swellings (type II papillae) were seen on the lip of the ventral sucker. The tegumental spines around the oral sucker were 5-9 pointed, whereas those between the two suckers were 12-17 pointed. Ventrolaterally, three groups of 5-6 type I papillae were located between the oral and ventral suckers, with single ones alternating between them. The genital sucker was protruded or depressed, depending on the contraction state of the flukes, and the gonotyl spine number ranged 50-60. The number of tip points of tegumental spines was decreased posteriorly; finally they became 1-3 pointed. On the dorsal surface, 4 groups of 4-5 type I papillae were symmetrically located on both lateral sides, and the shape and distribution of tegumental spines were similar to those of the ventral surface. Although the tegumental ultrastructure of H. nocens was generally similar to those of other heterophyids, the genital sucker morphology including the number of gonotyl spines and/or the distribution pattern of tegumental spines and sensory papillae were suggested to be the characteristic features of H. nocens.

Animals↗

PubMed1991

Somatostatin inhibits pepsinogen secretion via a cyclic AMP-independent pathway.

Frog esophageal mucosa contains peptide glands which release pepsinogen in response to a variety of secretagogues and serves as a model to examine the inhibitory action of somatostatin. The pepsinogen secretion in response to bethanechol was inhibited by somatostatin in a noncompetitive fashion. The maximal response induced by bethanechol was reduced and the EC50 for bethanechol was increased in the presence of somatostatin. On the other hand, somatostatin showed essentially no effect on pepsinogen release evoked by ionophore A23187, dibutyryl cAMP or by forskolin in the presence of atropine. Atropine was included in the incubation mixture to eliminate the effect of acetylcholine released by forskolin from the intrinsic cholinergic neurons also present in the mucosa. Somatostatin did not exert any significant effect on the basal or the forskolin-stimulated cAMP accumulation in the mucosa, nor the basal or the forskolin-stimulated adenylate cyclase activity in the membranes of the peptic cells isolated from the mucosa. Thus, these results seem to suggest that somatostatin inhibits pepsinogen secretion from frog esophageal mucosa by a cAMP-independent pathway.

Adenylyl Cyclases↗

PubMed1991

Run-down of neuromuscular transmission during repetitive nerve activity by nicotinic antagonists is not due to desensitization of the postsynaptic receptor.

1. Whether the function of the postsynaptic acetylcholine receptor is use-dependently affected by repetitive nerve stimulation in the presence of competitive antagonists was studied in the mouse phrenic nerve-hemidiaphragm preparation. 2. For electrophysiological experiments, the preparation was immobilized by synthetic mu-conotoxin, which preferentially blocks muscular Na-channels causing neither depolarization of the membrane potential, inhibition of quantal transmitter release, nor depression of nicotinic receptor function. 3. High concentrations of cobratoxin depressed indirect twitches and endplate potentials (e.p.ps) without inducing waning of contractilities or run-down of trains of e.p.ps evoked at 10-100 Hz. However, waning and run-down were accelerated after washout of the toxin despite diminished postsynaptic receptor blockade. Once the run-down of e.p.ps was produced by washout or low concentrations of cobratoxin, further depression of e.p.p. amplitude with high concentrations of cobratoxin did not attenuate the e.p.p. run-down. 4. The degrees of waning of tetanus and trains of e.p.ps produced by a very high concentration of tubocurarine (20 microM) were also less than that caused at a 100 fold lower concentration, albeit the amplitudes of twitches and the first e.p.p. were depressed more rapidly and markedly. 5. Tubocurarine, like cobratoxin, depressed the amplitude of miniature endplate potentials (m.e.p.ps) more than e.p.ps. 6. In contrast to the steepened run-down of successive e.p.ps in the presence of low concentrations of either nicotinic antagonists, the amplitude of m.e.p.ps observed during repetitive stimulation was uniform and was not different from that before stimulation. 7. The results suggest that the e.p.p. run-down and tetanic fade induced by nicotinic antagonists are due to a slow kinetic blockade of presynaptic receptors and confirm that the e.p.p. run-down is not produced by a use-dependent failure of postsynaptic nicotinic receptors. The roles of the presynaptic nicotinic receptor in positive or negative feedback modulations of transmitter release are discussed.

Acetylcholine↗

PubMed1991

Reciprocal mesenchymal-epithelial interaction affecting prostate tumour growth and hormonal responsiveness.

A novel cell-cell recombination model was established to test the reciprocal mesenchymal (fibroblast)-epithelial interaction in the prostate gland. Both growth factors and ECM pathways were found to be actively engaged during cellular communications. The application of this cell-cell recombination concept to prostate cancer established a new human prostate cancer animal model in which the tumours actively secrete prostate specific antigen, a known human prostate cancer marker. This review explores the significance of mesenchymal-epithelial interaction in determining prostate hormonal responsiveness and prostate cell transformation and speculates on the potential roles of mesenchymal-epithelial interaction in prostate cancer growth and progression.

Adenocarcinoma↗

PubMed1991

Surface ultrastructure of the developmental stages of Heterophyopsis continua (Trematoda: Heterophyidae).

Ultrastructural observations were made on the tegument of juvenile and adult stages of Heterophyopsis continua using scanning electron microscopy. On the surface posterior to the ventral sucker, the tegumental processes were bandlike in the metacercariae, cobblestonelike in the flukes 2 days postinfection (PI), and velvety at 3 days PI. The anterior surface between the oral and ventral suckers of the metacercariae was packed densely with tegumental spines having a 10- to 14-pointed tip. In flukes 6 days PI, the number of points increased to 15-17. The tegumental spines immediately behind the ventral sucker on the metacercariae surface possessed 5-7 points; posteriorly the points were reduced in size and in number. Ciliate sensory papillae (type I), as single or clumped forms of 2 or 3, were abundant around the oral and ventral suckers of metacercaria and adult worms. The clumped papillae appeared bilaterally symmetrical on the dorsal and ventral surfaces. The ciliate papillae may function in tango-, rheo-, and/or chemoreception. On the lip of the ventral sucker, 6-7 aciliate domed papillae (type II) were arranged in an equidistant manner. At 2 days PI each type II papilla became a clumped form having 2 or 3 papillae. Type II papillae may function as tango- and/or pressure-receptors. The structure and distribution of papillae suggest that the ventral sucker likely functions as a holdfast organ and the oral sucker as a probing organ involved in feeding.

Animals↗

PubMed1991

Hyperpolarization of denervated skeletal muscle by lemakalim and its antagonism by glybenclamide and tolbutamide.

Innervated skeletal muscles are endowed with K+ channels activatable by K+ channel openers. It is of interest to know whether the denervation-induced depolarization is due to a deficiency of such a K+ channel. In denervated mouse diaphragm, lemakalim, a K+ channel opener, effectively hyperpolarizes membrane and reduces membrane resistance, spontaneous activity as well as twitch force reversibly. Reductions of transmembrane K+ gradient diminish the lemakalim-induced hyperpolarization. In voltage-clamped fiber, lemakalim induces a long-lasting outward current. A current clamp experiment suggests a reversal potential of around -90 mV. On innervated diaphragm, lemakalim hyperpolarizes membrane and increases conductance if the muscle is predepolarized by anodal current. Lemakalim, however, is much less effective in overcoming the depolarization caused by crotamine, which activates Na+ channel. The effects of lemakalim are not attenuated by blockades of membrane Na+, Ca++ and Cl- permeabilities. Glybenclamide and tolbutamide, blockers of ATP-regulated K+ channel, antagonize the effects of lemakalim at low concentrations and produce slight membrane hyperpolarizations in denervated muscle, but marked membrane depolarizations in innervated muscle at higher concentrations. Cs+ depolarizes both innervated and denervated diaphragms and reduces the hyperpolarizing effect of lemakalim. The results suggest that lemakalim hyperpolarizes denervated muscle via glybenclamide sensitive K+ channels. It is inferred that a reduction of membrane K+ conductance rather than an increase of Na+ or Ca++ conductance contributes to the denervation-induced depolarization.

Animals↗

PubMed1991

Activity-dependent development of synaptic varicosities at crayfish motor terminals.

Tonically and phasically active crayfish motor terminals have well-characterized differences in synaptic physiology. During repetitive activation, the tonic terminals show facilitation and no depression, while the phasic terminals show dramatic synaptic fatigue. It has been proposed that this greater capacity for transmitter release from tonic terminals may be largely due to the presence of large synaptic varicosities along tonic terminals that contain large mitochondria, synapses, and numerous synaptic vesicles. In addition, a recent study indicates that in vivo tonic stimulation of a phasic terminal in young animals increases the fatigue resistance of the neuromuscular synapses and increases the number of synaptic varicosities, as well as the size of mitochondria and synapses. Because these previous morphological studies of crustacean motor terminals were performed using transmission electron microscopy, only short lengths of terminal were observed, and changes in synaptic varicosity frequency and size could not be thoroughly examined. In order to examine the synaptic varicosities along the terminal, motor terminals were injected with HRP, and the morphology of contrast-enhanced light microscopic images was examined. We report here that tonic terminals have much larger and more numerous synaptic varicosities than phasic terminals. In vivo stimulation of a phasic motoneuron results in an increase in the frequency of synaptic varicosities. This represents an increase in the total number of varicosities because terminal length appears to remain constant. These synaptic varicosities appear to form along preexisting terminals and persist for days after the final in vivo stimulation. The results indicate that the greater transmitter-releasing capabilities of tonic terminals compared to phasic terminals are due to their larger and more frequent synaptic varicosities. In addition, the development of these synaptic varicosities is activity dependent.

Animals↗

PubMed1990

Nicotinic actions of oxotremorine on murine skeletal muscle. Evidence against muscarinic modulation of acetylcholine release.

The effects of oxotremorine, arecoline and muscarine on neuromuscular transmission of mouse or rat phrenic nerve-diaphragm were investigated. For some studies of endplate potentials (e.p.p.s) the preparation was immobilized by cutting muscle fibers. Oxotremorine (0.3-10 microM) depolarized endplate membranes, reduced miniature e.p.p. amplitudes but increased frequency, induced spontaneous neural discharges and muscle fasciculations, and produced contracture of denervated mouse diaphragm. In mouse and young rat preparations pretreated with Mn2+, Co2+, Ni2+, Cd2+ or low Ca2+ Tyrode to depress evoked acetylcholine release, oxotremorine 0.3-1 microM increased indirect twitches as well as amplitudes and quantal contents of e.p.p.s. These increases were not observed when the synaptic transmission was not depressed, nor in adult rat preparations. The augmentation by oxotremorine of evoked acetylcholine release persisted in preparations pretreated with neostigmine (1 microM) and tetrodotoxin (20 nM), which inhibited acetylcholinesterase and oxotremorine-induced spontaneous neural discharges. These effects of oxotremorine were mimicked by arecoline but not by muscarine and were antagonized by tubocurarine (0.3 microM) but not by atropine (0.1-10 microM). Atropine alone did not affect indirect twitches, synaptic transmission, tetanic responses evoked by direct stimulation of diaphragms, nor the durations of muscle action potential. The direct twitch responses were only slightly increased by oxotremorine at 2-3 microM. Oxotremorine at high concentrations (greater than 2 microM), depressed indirect twitches and e.p.p. amplitude, and accelerated the run-down of trains of e.p.p.s. The IC50 on indirect twitches was reduced by pretreatment with diltiazem or proadifen, which are known to promote receptor desensitization.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗

PubMed1990

Organic calcium channel antagonists provoke acetylcholine receptor autodesensitization on train stimulation of motor nerve.

The effects of nicardipine and other organic Ca2(+)-channel antagonists on the responses induced by indirect train stimulation (3 s, 50-100 Hz) were studied in mouse phrenic nerve diaphragm preparations. Nicardipine at 1-10 microM, which alone did not affect single or tetanic contractions or the amplitude of evoked endplate potentials and spontaneous miniature endplate potentials, caused tetanic contraction to fade completely in the presence of 0.3 microM neostigmine or 50 microM diisopropylfluorophosphate. In combination with these anticholinesterases, nicardipine caused a severe run-down and shortening of endplate potentials in 1-2 s. This effect on endplate potentials was dependent on stimulus frequency and on extracellular Ca2+. The effect was accelerated by intracellular injection of Ca2+, but retarded by injection of EGTA. The amplitudes of miniature endplate potentials and the evoked endplate depolarization were also depressed during repetitive stimulation. On termination of repetitive stimulation, all postsynaptic responses, including evoked endplate potentials, miniature endplate potentials and single twitches, recovered to pre-train level in 3-10 s. These results suggest that the postsynaptic nicotinic receptors had lost the functional activity during repetitive stimulation. The time-courses of the aforementioned changes initiated by repetitive stimulation were similar to the fast phase of desensitization induced by acetylcholine. The irreversible action of alpha-bungarotoxin on acetylcholine receptor was attenuated in the presence of nicardipine and neostigmine if repetitive stimulation was applied. The same effects were observed with other organic Ca2(+)-channel antagonists (diltiazem, verapamil and nifedipine) as well as agonist (methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)-pyr idine- 5-carboxylate, BAY K8644), but not with Mn2+, theophylline or caffeine. It is inferred that organic Ca2(+)-channel antagonists interact directly with acetylcholine receptor ion channel, enhance its autodesensitization liability and thus cause extinction of endplate potentials on repetitive stimulation.

Animals↗

PubMed1990

A new 180 kDa. urine protein marker associated with bladder cancer.

We surveyed the tumor-related proteins present in the urine specimens of 118 bladder cancer patients to seek a possible marker enabling future diagnosis and prognosis of this disease. We identified a protein of 180 kDa. by sodium dodecyl sulfate polyacrylamide gel electrophoresis in urine samples subjected to prior adsorption by protein-A conjugated to a sepharose bead. This protein appears to be a glycoprotein because it binds to concanavalin A-conjugated sepharose and can be eluted by alpha-methyl D-mannoside. It does not react immunochemically with antibodies prepared against either carcinoembryonic antigen or epidermal growth factor receptor, both of which have an apparent molecular weight close to 180 kDa. We found this protein in the urine of 74.3% of the patients with transitional cell carcinoma. It was not present in age-matched controls, patients with benign prostatic hyperplasia or patients with 10 other cancers. There was 1 false positive result in a patient with prostate cancer. It does not appear to be associated with urinary tract infection, blood contamination, premedication or anesthesia.

Adult↗

PubMed1990

Fibroblast-mediated acceleration of human epithelial tumor growth in vivo.

Transformed fibroblasts coinoculated with epithelial cells accelerated the growth and shortened the latency period of human epithelial tumors in athymic mice. Addition of NbF-1 fibroblasts caused epithelial tumors to grow from five marginally tumorigenic or "nontumorigenic" (nontumor-forming) human tumor cell lines or strains: PC-3 (prostate), WH (bladder), MDA-436 (breast), and cells derived from the ascites fluids of patients with metastatic renal pelvic or prostate cancers. Evidence for the human and epithelial nature of these experimental tumors was provided by histologic, immunohistochemical, Southern and dot-blot hybridization, and cytogenetic analyses. Transformed fibroblasts induced predominantly carcinosarcomas, whereas nontumorigenic fibroblasts (NIH 3T3) and lethally irradiated transformed fibroblasts induced exclusively carcinomas. The fibroblast-epithelial interaction appears to occur bidirectionally and does not result from cell fusion. Because coculture experiments in vitro did not demonstrate an increased cell proliferation, it appears that undefined host factors can influence tumor growth. This tumor model may be useful in drug-screening programs and in mechanistic studies of factors regulating human tumor growth and progression.

Animals↗

PubMed1990

Facilitation by 3,4-diaminopyridine of regenerative acetylcholine release from mouse motor nerve.

1. Effects of 3,4-diaminopyridine (DAP) on endplate potentials (e.p.ps) were studied in mouse phrenic nerve-hemidiaphragms. 2. In cut muscle preparations, low concentrations of DAP (2-20 microns) increased the amplitude of e.p.ps and shifted the curve relating Ca2+ concentration to e.p.p. amplitude leftward. 3. High concentration of DAP (40-4000 microns) prolonged the duration of e.p.ps dose-dependently up to one hundred fold (ca. 200 ms), yielding, in addition to the normal phasic e.p.p., a prolonged plateau depolarization component which was often preceded by an upstroke depolarization. During the plateau depolarization, nerve stimulations did not evoke any e.p.p. 4. The plateau component of prolonged e.p.ps was suppressed by tubocurarine, verapamil, nifedipine, Mn2+ and Cd2+ (but not by atropine) at low concentrations that had negligible effect on the amplitude of miniature e.p.ps or the phasic component of e.p.ps. Abolition of the plateau component by these agents restored the capability of the nerve terminal to evoke e.p.ps on nerve stimulation. 5. Low concentrations of neostigmine (0.01-0.02 microns) markedly lengthened DAP-prolonged e.p.ps. However, the regenerative endplate depolarization evoked in the presence of high concentrations of neostigmine (0.3-0.5 microns) was not prolonged by DAP. 6. Tetraethylammonium (1 mM) did not provoke prolonged e.p.ps but acted cooperatively with DAP to prolong the duration of plateau depolarization. At a high concentration (3 mM), tetraethylammonium depressed the amplitude of miniature e.p.ps and abolished DAP-prolonged e.p.ps. 7. In uncut muscle preparations, DAP apparently did not modify the time course and amplitude of miniature e.p.ps. Upon direct stimulation by current injection at endplate, DAP increased the muscle action potentials by only about 30%, but induced no prolonged depolarization. 8. These results suggest that the prolonged e.p.ps induced in the presence of DAP are due to a regenerative release of acetylcholine from motor nerve and the induction probably involves a presynaptic Ca2+ channel different from that for normal e.p.ps. It may be inferred that the regenerative acetylcholine release is recruited by Ca2 + channels modulated by nicotinic receptors and K+ channels.

4-Aminopyridine↗

PubMed1990

Recovery rate, growth and development of Heterophyopsis continua in experimental chicks.

The growth and developmental pattern of H. continua was observed after experimental infection of their metacercariae to chicks. The recovery rate of worms from the chicks at 1 to 28 days post-infection (PI) was 12.8% in average. The rate remained fairly high for early 4 days of infection but decreased thereafter rapidly till 28 days PI. Most of the flukes, 91.9%, were recovered from the ileum of the chicks. In metacercariae, genital organs such as the ovary, testes, seminal vesicle, seminal receptacle and genital sucker were recognizable. At one day PI Mehlis' gland appeared, and at 2 days follicular vitellaria were observed. At 3 days PI, eggs were formed in the uterine tubule and increased in number as the worm grew old. The worms reached 2,990 microns in length and 525 microns in width at 28 days PI. Genital organs developed rapidly in early stages of infection but slowly thereafter to 28 days PI, whereas non-genital organs developed steadily through the infection period. It was proved by this experiment that chicks should be a moderately suitable final host of H. continua.

Animals↗

PubMed1990

[Intestinal parasite infections among inhabitants in two islands of Tongyeong-gun, Kyeongsangnam-do].

This study was performed to evaluate the status of intestinal parasitic infections among the inhabitants in two islands (Chu-do and Doomi-do) of Tongyeong-gun, Kyeongsangnam-do (Province), from August to September, 1989. A total of 189 stool specimens was collected from the inhabitants of 3 villages and examined by Kato's cellophane thick smear and formalin-ether sedimentation techniques. Stoll's dilution egg counting technique was done for the quantitative examination of helminth eggs. The overall positive rate of intestinal parasites was 30.2%. The egg positive rate of Ascaris lumbricoides was 2.1%, that of Trichuris trichiura 24.3%, hookworm 2.1%, Trichostrongylus orientalis 0.5%, Clonorchis sinensis 1.1%, heterophyid 1.6%, and Taenia species 2.6%. The cyst positive rate of Giardia lamblia was 1.6% and that of Entamoeba coli 0.5%. In T. trichiura infection, the egg positive rate of females (29.9%) was much higher than that of males (17.2%). Among the age groups, 10-19 year group showed the highest infection rate, 32.4%. It was revealed that the prevalence of intestinal parasitic infections among the inhibitants of remote islands should be still high in comparison with ever-reported ones in urban or rural areas.

Adolescent↗

PubMed1990

The role of mammography on breast cancer patients in a hospital setting.

From Oct. 1, 1983 to May 31, 1988, 6198 mammograms were taken and 443 mastectomies were performed at the Yonsei University Hospital, Seoul, Korea. Of these, 191 cases had preoperative mammography performed prior to surgery (study group) and 252 cases underwent mastectomies without preoperative mammography (control group). There were no significant differences between the two groups in pathological stages, axillary lymph node metastasis and size of the tumor, suggesting that little benefit is derived from the preoperative mammography in the hospital setting. However, there were a number of other findings, including a 14% incidence of multiple foci and localization of non-palpable cancer in 3% of cases, that could help us to make therapeutic plans and strategies for these patients.

Breast Neoplasms↗