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1.
Biomicrofluidics ; 12(5): 054105, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30310526

ABSTRACT

Flow lithography (FL) is a microfluidic technique distinguished for its ability to produce hydrogel microparticles of various geometrical and chemical designs. While FL is typically performed in room temperature, this paper reports a new technique called low temperature flow lithography that uses low synthesis temperature to increase the degree of polymerization of microparticles without compromising other aspects of flow lithography. We suggest that decreased oxygen diffusivity in low temperature is responsible for the increase in polymerization. Microparticles that exhibit a higher degree of polymerization display a more developed polymer network, ultimately resulting in a more defined morphology, higher incorporation of materials of interest, and improved functional performance. This work demonstrates the increase in the degree of polymerization by examining the temperature effect on both the physical and chemical structures of particles. We show applications of this technique in synthesizing thin microparticles and enhancing microparticle-based detection of microRNA. Low temperature FL offers a simple and easy method of improving the degree of polymerization, which can be implemented in a wide range of FL applications.

2.
Biomicrofluidics ; 12(6): 069901, 2018 11.
Article in English | MEDLINE | ID: mdl-30867869

ABSTRACT

[This corrects the article DOI: 10.1063/1.5047016.].

5.
Plant Cell Rep ; 22(4): 268-73, 2003 Nov.
Article in English | MEDLINE | ID: mdl-12920565

ABSTRACT

The anther (tapetum)-specific gene BcA9 was isolated from Chinese cabbage, Brassica campestris L. ssp. pekinensis cv. Jangwon, using the Arabidopsis tapetum-specific A9 gene as a probe. The DNA and amino acid sequences of the coding region of the BcA9 gene showed high homology with A9 genes from Arabidopsis and B. napus. However, the DNA sequences of the 5' noncoding (promoter) region were different, except for the sequence from -281 to -89. To test the specific activity of this promoter, a plant expression vector, pGR011, was constructed by fusing the BcA9 promoter and the cytotoxic diphtheria toxin A-chain (DTx-A) gene. Several transgenic plants from cabbage, B. oleracea ssp. capitata, were obtained by way of Agrobacterium-mediated transformation. Southern blot analysis indicated that the tapetum-specific BcA9 promoter and DTx-A gene were successfully integrated into the genome of the transgenic cabbage. Under the control of the BcA9 promoter, expression of the cytotoxic DTx-A gene in the tapetal cells of the transgenic plants resulted in male sterile cabbages. Microscopic examination revealed that pollen grains in anthers of the male sterile cabbages had not developed normally, but the vegetative growth and phenotype showed no difference compared to wild-type plants.


Subject(s)
Brassica/genetics , Promoter Regions, Genetic , Base Sequence , Brassica/physiology , Cloning, Molecular , DNA, Plant , Molecular Sequence Data , Plants, Genetically Modified , Sequence Homology, Nucleic Acid
6.
Laryngoscope ; 111(9): 1599-602, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11568612

ABSTRACT

OBJECTIVES: This study was undertaken to measure the distance and the angle between the anterior part of nasal cavity and the natural ostium of the sphenoid sinus. The anatomical location of the natural ostium according to the direction of surgeon's operating view toward the anterior wall of the sphenoid sinus was also analyzed. STUDY DESIGN: This study used careful cadaver dissection under a surgical microscope. METHODS: One hundred sagittally sectioned adult cadaveric heads were used. We measured the distances and angles for identifying the natural ostium of the sphenoid sinus using several reference points such as the limen nasi, the sill, and the posteroinferior end of the superior turbinate. In addition, we tried to identify whether the location of the natural ostium is medial or lateral to the posterior end of the superior turbinate. RESULTS: The natural ostium of the sphenoid sinus was located at an angle of 35.9 degrees with a distance of 56.5 mm from limen nasi and at an angle of 34.3 degrees with a distance of 62.7 mm from nasal sill. It was located approximately 1 cm above the posteroinferior end of the superior turbinate and at a medial aspect to the posterior end of the superior turbinate in 83% of specimens. CONCLUSIONS: We speculate that the posteroinferior end of the superior turbinate is the best landmark for identifying the natural ostium of the sphenoid sinus. Furthermore, the natural ostium should ideally be searched from a superior and medial aspect in relation to the posteroinferior end of the superior turbinate.


Subject(s)
Anthropometry , Sphenoid Sinus/anatomy & histology , Sphenoid Sinus/surgery , Adult , Anthropometry/methods , Cadaver , Dissection , Endoscopy , Humans , Nasal Cavity/anatomy & histology , Reference Values , Sphenoid Sinus/ultrastructure , Turbinates/anatomy & histology
7.
Laryngoscope ; 111(4 Pt 1): 603-8, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11359127

ABSTRACT

OBJECTIVES: Although complete anatomical knowledge of the nasofrontal duct has been of great importance, little is known about it. The aim of this study is to examine the drainage site of the nasofrontal duct and to investigate the anatomical boundaries of the nasofrontal duct according to the drainage site. STUDY DESIGN: One hundred sagittally divided adult head specimens were analyzed by computed tomography and dissection under the surgical microscope. METHODS: Computed tomography scans of 50 adult cadaver heads were taken sagittally at 1-mm intervals and coronally at 3-mm intervals to find the nasofrontal duct. One hundred specimens, made up of sagittally divided adult cadaver heads, were dissected under the microscope to study the structure of the nasofrontal duct. RESULTS: We identified the anterior, posterior, medial, and lateral boundaries of the nasofrontal duct. In the most common type, the superior portion of the uncinate process formed the anterior border and the superior portion of the bulla ethmoidalis formed the posterior border of the nasofrontal duct. The conchal plate formed the medial border and the suprainfundibular plate formed the lateral border of the nasofrontal duct. Other variations are described in detail. CONCLUSIONS: To widen the nasofrontal communication, removing the upper portion of the ground lamella of the ethmoid bulla, which is the posterior boundary of the nasofrontal duct, with cutting forceps seems to be a safe and easy method.


Subject(s)
Frontal Sinus/anatomy & histology , Adult , Cadaver , Dissection , Frontal Sinus/diagnostic imaging , Humans , Nasal Cavity/anatomy & histology , Tomography, X-Ray Computed
8.
Laryngoscope ; 111(5): 900-4, 2001 May.
Article in English | MEDLINE | ID: mdl-11359174

ABSTRACT

OBJECTIVES/HYPOTHESIS: This study was undertaken to examine three main relationships. First, the distance and angle from the anterior ethmoidal canal to the limen nasi and the sill were measured. Second, the location of the anterior ethmoidal canal was examined in relation to the lamellas and the skull base. Third, the existence of bony defects in the canal and the course of the canal through the anterior cranial fossa were studied. STUDY DESIGN: This study employed both sagittal computed tomography and cadaver dissection. METHODS: Seventy sagittally divided heads from randomly chosen Korean adult cadavers were used. Sagittal computed tomography was performed on all specimens. Then they were meticulously dissected under a surgical microscope. RESULTS: The mean distance and angle between the limen nasi and the anterior ethmoidal canal were 49.0 mm and 54.5 degrees, respectively. The anterior ethmoidal canal was located between the second and third lamella in 61 of 70 cases. In 60 of 70 cases it was attached to the base of the skull, and in the remaining 10 cases it ran 2 to 3 mm below the skull base. When viewed from the superior side, the course of the anterior ethmoidal canal formed a diagonal line from the lateral to the medial side. Partial bony defects of the anterior ethmoidal canal were observed in eight cases, and complete bony defects in none. CONCLUSION: This study provides surgeons with a better understanding of the anatomy of the anterior ethmoidal canal.


Subject(s)
Ethmoid Bone/anatomy & histology , Adult , Ethmoid Bone/surgery , Humans , Skull Base/anatomy & histology
9.
Plant Physiol ; 126(1): 330-41, 2001 May.
Article in English | MEDLINE | ID: mdl-11351096

ABSTRACT

Plastid lipid-associated protein (PAP), a predominant structural protein associated with carotenoids and other non-green neutral lipids in plastids, was shown to be encoded by a single nuclear gene in several species. Here we report three PAP genes in the diploid Brassica rapa; the three PAPs are associated with different lipids in specific tissues. Pap1 and Pap2 are more similar to each other (84% amino acid sequence identity) than to Pap3 (46% and 44%, respectively) in the encoded mature proteins. Pap1 transcript was most abundant in the maturing anthers (tapetum) and in lesser amounts in leaves, fruit coats, seeds, and sepals; Pap2 transcript was abundant only in the petals; and Pap3 transcript had a wide distribution, but at minimal levels in numerous organs. Immunoblotting after sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that most organs had several nanograms of PAP1 or PAP2 per milligram of total protein, the highest amounts being in the anthers (10.9 microg x mg(-1) PAP1) and petals (6.6 microg x mg(-1) PAP2), and that they had much less PAP3 (<0.02 microg x mg(-1)). In these organs PAP was localized in isolated plastid fractions. Plants were subjected to abiotic stresses; drought and ozone reduced the levels of the three Pap transcripts, whereas mechanical wounding and altering the light intensity enhanced their levels. We conclude that the PAP gene family consists of several members whose proteins are associated with different lipids and whose expressions are controlled by distinct mechanisms. Earlier reports of the expression of one Pap gene in various organs in a species need to be re-examined.


Subject(s)
Brassica/genetics , Genes, Plant , Lipid Metabolism , Plastids/metabolism , Amino Acid Sequence , Base Sequence , Brassica/growth & development , DNA Primers , Diploidy , Introns , Molecular Sequence Data , Pancreatitis-Associated Proteins , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Homology, Amino Acid
10.
Laryngoscope ; 111(3): 424-9, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11224770

ABSTRACT

OBJECTIVES: To investigate the exact anatomical structure of the lamellas in the ethmoid sinus by computed tomography (CT) and anatomical analysis. STUDY DESIGN: Cadaver dissections and CT scans were used to compare lamellar structures and their radiological images. METHODS: Anatomical microdissection of 100 midsagittal sections from adult cadaver head specimens were examined and compared with those of sagittal CT scans at 1-mm intervals. RESULTS: The posteroinferior end of the uncinate process attaching to the inferior turbinate divided the fontanelle into the anterior and posterior portions in the majority of cases. The basal lamellas of the bulla ethmoidalis were subdivided into three major types. The posteroinferior portion of its basal lamella was connected to the lower horizontal portion of the third basal lamella in all cases. The anterior indentation of the third lamella was identified in nine cases, but there was no indentation in the posterior direction. The basal lamella of the superior turbinate was attached to the skull base superiorly either separately or fused to the third lamella, and its posteroinferior portion was attached to the lowest portion of the anterior wall of the sphenoid sinus. The supreme turbinate existed in 50 cases; however, its basal lamella was identified in only 15 cases. CONCLUSIONS: Our results indicate that the lamellas of the ethmoid sinus have relatively uniform patterns, although there is variability in shape. It is hoped that this study will provide surgeons with a more detailed structure of the basal lamellas for better surgical results and lower complication rates.


Subject(s)
Basement Membrane/diagnostic imaging , Ethmoid Sinus/diagnostic imaging , Tomography, X-Ray Computed , Adult , Basement Membrane/anatomy & histology , Ethmoid Sinus/anatomy & histology , Humans , Reference Values , Turbinates/anatomy & histology , Turbinates/diagnostic imaging
11.
Laryngoscope ; 110(12): 2110-3, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11129031

ABSTRACT

OBJECTIVES/HYPOTHESIS: Mucus hypersecretion is a common feature in chronic sinusitis with polyps. Because mucus hypersecretion is commonly accompanied by goblet cell hyperplasia, it is important to identify which mucin gene mRNAs are expressed in the goblet cells of the surface epithelium in the human airway. This study aims to investigate the pattern of expression of MUC5AC messenger RNA (mRNA) in the goblet cells of human nasal mucosa. METHODS: Six nasal polyps, five inferior turbinate mucosa specimens, and three normal-appearing mucosa specimens of the posterior ethmoid sinus were obtained. Each of the specimens was cut into 10-microm-thick serial frozen sections, and in situ hybridization of MUC5AC mRNA was performed with an oligonucleotide probe. Alcian blue (pH 2.5)-periodic acid-Schiff (AB-PAS) staining was performed on the serial sections. RESULTS: In human nasal polyps, MUC5AC mRNA was expressed in the cytoplasm of most of the goblet cells. However, in the inferior turbinate, MUC5AC mRNA was expressed in only some of the goblet cells. On the contrary, in the normal-appearing mucosa of the posterior ethmoid sinus, MUC5AC mRNA was barely expressed in the goblet cells. Furthermore, MUC5AC mRNA was mainly expressed in some of the PAS-positive goblet cells. CONCLUSIONS: Only a portion of the goblet cells in the human nasal mucosa expressed MUC5AC mRNA. This result suggests that surface goblet cells might have other mucin genes, in addition to MUC2 and MUC5AC.


Subject(s)
Goblet Cells/metabolism , Mucins/metabolism , Nasal Mucosa/cytology , Nasal Polyps/metabolism , RNA, Messenger/metabolism , Humans , In Situ Hybridization , Mucin 5AC , Nasal Mucosa/metabolism , Nasal Polyps/pathology , Sinusitis/metabolism , Sinusitis/pathology
12.
Mol Cells ; 10(4): 399-404, 2000 Aug 31.
Article in English | MEDLINE | ID: mdl-10987136

ABSTRACT

Non-redundant expressed sequence tags (ESTs) were generated from six different organs at various developmental stages of Chinese cabbage, Brassica rapa L. ssp. pekinensis. Of the 1,295 ESTs, 915 (71%) showed significantly high homology in nucleotide or deduced amino acid sequences with other sequences deposited in databases, while 380 did not show similarity to any sequences. Briefly, 598 ESTs matched with proteins of identified biological function, 177 with hypothetical proteins or non-annotated Arabidopsis genome sequences, and 140 with other ESTs. About 82% of the top-scored matching sequences were from Arabidopsis or Brassica, but overall 558 (43%) ESTs matched with Arabidopsis ESTs at the nucleotide sequence level. This observation strongly supports the idea that gene-expression profiles of Chinese cabbage differ from that of Arabidopsis, despite their genome structures being similar to each other. Moreover, sequence analyses of 21 Brassica ESTs revealed that their primary structure is different from those of corresponding annotated sequences of Arabidopsis genes. Our data suggest that direct prediction of Brassica gene expression pattern based on the information from Arabidopsis genome research has some limitations. Thus, information obtained from the Brassica EST study is useful not only for understanding of unique developmental processes of the plant, but also for the study of Arabidopsis genome structure.


Subject(s)
Brassica/genetics , Expressed Sequence Tags , Gene Expression Profiling , Genome, Plant , Arabidopsis/genetics , Databases as Topic , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
13.
Dermatol Surg ; 26(7): 702-4, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10886287

ABSTRACT

BACKGROUND: Suction devices for epidermal grafting need a suction pump to provide a negative pressure. The authors have developed a suction device in which a syringe and a manometer are employed to provide a negative pressure. OBJECTIVE: The purpose of this study was to evaluate the efficacy of our suction device in vitiligo patients. METHODS: The suction device was used to obtain epidermal blisters from the donor site. A CO2 laser was employed to remove the depigmented epidermis. The blister roofs of the donor site were harvested and were placed onto the recipient area. Ten patients with stable vitiligo were treated by epidermal grafting. RESULTS: Epidermal blisters were produced by suction in all patients. Also, all 10 patients regained repigmentation. CONCLUSION: Our suction blister device is simple and inexpensive to make, and it may become an alternative to the other suction devices.


Subject(s)
Epidermis/transplantation , Manometry/instrumentation , Syringes , Vitiligo/surgery , Adolescent , Adult , Blister , Female , Humans , Male , Middle Aged , Suction/instrumentation , Transplantation, Autologous
15.
Acta Otolaryngol ; 119(8): 905-10, 1999.
Article in English | MEDLINE | ID: mdl-10728932

ABSTRACT

Little is known about the regulatory effects of cytokines on various nasal secretions in normal human nasal epithelial cells. The aim of this study was to examine whether TNF-alpha, IL-1beta or their combination can increase the secretion of mucin as an indicator of mucous secretion, the secretion of lysozyme as an indicator of serous secretion and the secretion of IL-6 and IL-8 as important cytokines. In addition, we wanted to examine their message levels in normal human nasal epithelium. On day 12 of culture, passage-2 normal human nasal epithelial cells were treated with 10 ng/ml TNF-alpha, 10 ng/ml IL-1beta and combinations of both. Twenty-four hours later, the apical secretions were collected. A mixture of TNF-alpha and IL-1beta synergistically increased secretion of mucin, IL-6 and IL-8, but did not increase secretion of lysozyme. A combination of TNF-alpha and IL-1beta showed a questionable increase of MUC2 mRNA levels. TNF-alpha, IL-1beta and a combination of both all significantly increased MUC8 mRNA levels. Neither TNF-alpha, IL-1beta nor a combination of both increased MUC5AC, MUC5B and lysozyme mRNA levels. IL-1beta alone or a combination of TNF-alpha and IL-1beta comparably increased IL-6 and IL-8 mRNA levels slightly. In conclusion, a mixture of inflammatory mediators can synergistically increase secretion of mucin, IL-6 and IL-8 in human nasal epithelium. Accordingly, nasal secretions may be under the control of an inflammatory mediator network.


Subject(s)
Interleukin-1/pharmacology , Interleukin-6/metabolism , Interleukin-8/metabolism , Mucins/metabolism , Muramidase/metabolism , Nasal Mucosa/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Cells, Cultured , Epithelium/metabolism , Humans , Immunologic Techniques , Interleukin-6/genetics , Interleukin-8/genetics , Mucins/genetics , Muramidase/genetics , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction
16.
Br J Dermatol ; 138(2): 351-3, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9602890

ABSTRACT

We report a case of subcutaneous phaeohyphomycosis due to Exophiala jeanselmei in an 84-year-old Korean farmer suffering from pulmonary tuberculosis. He presented with six subcutaneous, fluctuant abscesses on the left distal forearm and wrist. Subcutaneous infections by E. jeanselmei mostly present as a solitary cyst or abscess on an extremity. The present case showed localized multiple abscesses suggesting metastatic tuberculous abscesses or other pyogenic bacterial infections.


Subject(s)
Dermatomycoses/microbiology , Exophiala/isolation & purification , Tuberculosis, Pulmonary/complications , Aged , Aged, 80 and over , Humans , Male , Recurrence
17.
Mol Cells ; 7(1): 21-7, 1997 Feb 28.
Article in English | MEDLINE | ID: mdl-9085260

ABSTRACT

The promoter regions of two genomic clones, GBAN215-6 and GBAN215-12 from Chinese cabbage (Brassica campestris L. ssp. pekinensis), were sequenced. The nucleotide sequences of their promoter regions were compared with that of the Bp19 pollen-specific gene of Brassca napus. High nucleotide sequence homologies were observed among these three genes in the region between 210 bp upstream and the putative transcription start site. A sequence motif TGTGGTG, which is similar to that of the PB core motif (TGTGGTT) of two tomato pollen-specific genes, LAT52 and LAT56, was present in these two cloned genes. To determine regulatory sequences responsible for the anther-specific expression of the gene BAN215-6, two recombinant plasmids, pBPE3 (-274- + 109) and pBPE4 (-816- + 109) containing different lengths of the promoter fused with the GUS gene, were constructed and introduced into tobacco plants by Agrobacterium-mediated transformation. The result showed that the 383 bp (-274- + 109) of the BAN215-6 promoter region was sufficient for the anther-specific expression of the GUS gene. The GUS expression in a tobacco plants transformed with these constructs was first detected in uninucleate microspores and persisted at in vitro germinated pollen tubes. The expression level was increased during anther development, reaching the highest level in mature pollens.


Subject(s)
Carboxylic Ester Hydrolases/genetics , Genes, Plant , Promoter Regions, Genetic , Brassica/enzymology , Brassica/genetics , Cloning, Molecular , DNA, Plant/genetics , Glucuronidase/genetics , Molecular Sequence Data , Plants, Genetically Modified , Plants, Toxic , Pollen/enzymology , Pollen/genetics , Sequence Homology, Nucleic Acid , Nicotiana/enzymology , Nicotiana/genetics , Transformation, Genetic
18.
Plant Mol Biol ; 33(1): 193-8, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9037172

ABSTRACT

Two cDNA libraries were constructed from poly(A)+ RNAs isolated from each of immature flowers (less than 2.0 mm long buds) and anthers (2.0-5.0 mm long buds) of Chinese cabbage (Brassica campestris L. ssp. pekinensis). Using dot-differential hybridization, three cDNA clones, designated BIF38, BAN54, and BAN237, have been isolated from the constructed cDNA libraries and sequenced completely in both directions. Northern blot analyses indicate that all three cDNA clones are abundantly expressed in anther, but not in leaf or other floral organs. The deduced amino acid sequences of BIF38, BAN54, and BAN237 showed high identity with those of known anther-specific genes. Especially the deduced amino acid sequence of BIF38 has 98% identity with that of a phospholipid protein gene (E2) from Brassica napus. Also, the deduced amino acid sequences of BAN54 and BAN237 are similar to the sequences of microspore-specific genes (Bp4A and Bp4C) and pollen oleosins (13, pol3 and C98), respectively. Southern blot analyses revealed that all three genes belong to multiple gene families in the Chinese cabbage genome.


Subject(s)
Brassica/genetics , Genes, Plant , Amino Acid Sequence , Base Sequence , DNA, Complementary , Gene Library , Molecular Sequence Data , Plant Proteins/biosynthesis , Plant Proteins/chemistry , Plant Proteins/genetics , Sequence Homology, Amino Acid
19.
J Dairy Sci ; 78(10): 2108-12, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8598396

ABSTRACT

A selective medium, blood-glucose-liver agar containing oxgall (.2 mg/ml) and gentamicin (30 micrograms/ml), was formulated for the selective enumeration of bifidobacteria in fermented dairy products containing both lactobacilli and streptococci. Recovery rates of bifidobacteria on this selective medium were around 90% of recovery on blood-glucose-liver agar. Strains of lactobacilli and streptococci were mostly inhibited with higher dilutions on this selective medium.


Subject(s)
Bifidobacterium/isolation & purification , Culture Media , Dairy Products/microbiology , Anti-Bacterial Agents , Bifidobacterium/drug effects , Bile Acids and Salts , Colony Count, Microbial , Fermentation , Gentamicins , Lactobacillus/drug effects , Microbial Sensitivity Tests , Streptococcus/drug effects , Yogurt/microbiology
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