Single-tooth anterior implant: a world of caution. Part I.
Explore the source record for details and available documents.
Aftercare↗
Biomedical subjects
J Lu
Publications and source records attributed to J Lu.
Single-tooth anterior implant: a word of caution. Part II.
Explore the source record for details and available documents.
Alveolar Ridge Augmentation↗
The MEF2A 3' untranslated region functions as a cis-acting translational repressor.
Myocyte enhancer factor 2 (MEF2) proteins serve as important muscle transcription factors. In addition, MEF2 proteins have been shown to potentiate the activity of other cell-type-specific transcription factors found in muscle and brain tissue. While transcripts for MEF2 factors are widely expressed in a variety of cells and tissues, MEF2 proteins and binding activity are largely restricted to skeletal, smooth, and cardiac muscle and to brain. This disparity between MEF2 protein and mRNA expression suggests that translational control may play an important role in regulating MEF2 expression. In an effort to identify sequences within the MEF2A message which control translation, we isolated the mouse MEF2A 3' untranslated region (UTR) and fused it to the chloramphenicol acetyltransferase (CAT) reporter gene. Here, we show by CAT assay that the MEF2A 3' UTR dramatically inhibits CAT gene expression in vivo and that this inhibition is due to an internal region within the highly conserved 3' UTR. RNase protection analyses demonstrated that the steady-state level of CAT mRNA produced in vivo was not affected by fusion of the MEF2A 3' UTR, indicating that the inhibition of CAT activity resulted from translational repression. Furthermore, fusion of the MEF2A 3' UTR to CAT inhibited translation in vitro in rabbit reticulocyte lysates. We also show that the translational repression mediated by the 3' UTR of MEF2A is regulated during muscle cell differentiation. As muscle cells in culture differentiate, the translational inhibition caused by the MEF2A 3' UTR is relaxed. These results demonstrate that the MEF2A 3' UTR functions as a cis-acting translational repressor both in vitro and in vivo and suggest that this repression may contribute to the tissue-restricted expression and binding activity of MEF2A.
Animals↗
A novel transcript encoding an N-terminally truncated AML1/PEBP2 alphaB protein interferes with transactivation and blocks granulocytic differentiation of 32Dcl3 myeloid cells.
The gene AML1/PEBP2 alphaB encodes the alpha subunit of transcription factor PEBP2/CBF and is essential for the establishment of fetal liver hematopoiesis. Rearrangements of AML1 are frequently associated with several types of human leukemia. Three types of AML1 cDNA isoforms have been described to date; they have been designated AML1a, AML1b, and AML1c. All of these isoforms encode the conserved-Runt domain, which harbors the DNA binding and heterodimerization activities. We have identified a new isoform of the AML1 transcript, termed AML1 deltaN, in which exon 1 is directly connected to exon 4 by alternative splicing. The AML1 deltaN transcript was detected in various hematopoietic cell lines of lymphoid to myeloid cell origin, as revealed by RNase protection and reverse transcriptase PCR analyses. The protein product of AML1 deltaN lacks the N-terminal region of AML1, including half of the Runt domain, and neither binds to DNA nor heterodimerizes with the beta subunit. However, AML1 deltaN was found to interfere with the transactivation activity of PEBP2, and the molecular region responsible for this activity was identified. Stable expression of AML1 deltaN in 32Dcl3 myeloid cells blocked granulocytic differentiation in response to granulocyte colony-stimulating factor. These results suggest that AML1 deltaN acts as a modulator of AML1 function and serves as a useful tool to dissect the functional domains in the C-terminal region of AML1.
Amino Acid Sequence↗
Functional role of Ca2+ currents in graded and spike-mediated synaptic transmission between leech heart interneurons.
We used intracellular recording and single electrode voltage-clamp techniques to explore Ca2+ currents and their relation to graded and spike-mediated synaptic transmissions in leech heart interneurons. Low-threshold Ca2+ currents (activation begins below -50 mV) consist of a rapidly inactivating component (I(CaF)) and a slowly inactivating component (I(CaS)). The apparent inactivation kinetics of I(CaF) appears to be influenced by Ca2+; both the substitution of Ca2+ (5 mM) with Ba2+ (5 mM) in the saline and the intracellular injection of the rapid Ca2+ chelator, bis-(o-aminophenoxy)-N,N,N',N'-tetraacetic acid (BAPTA), from the recording microelectrode, significantly increase its apparent inactivation time constant. The use of saline with a high concentration of Ba2+ (37.5 mM) permitted exploration of divalent ion currents over a broader activation range, by acting as an effective charge carrier and significantly blocking outward currents. Ramp and pulse voltage-clamp protocols both reveal a rapidly activating and inactivating Ba2+ current (I(BaF)) and a less rapidly activating and slowly inactivating Ba2+ current with a broad activation range (I(BaS)). Low concentrations of Cd2+ (100-150 microM) selectively block I(BaS), without significantly diminishing I(BaF). The current that remains in Cd2+ lacks the characteristic delayed activation peak of I(BaS) and inactivates with two distinct time constants. I(BaF) appears to correspond to a combination of I(CaF) and I(CaS), i.e., to low-threshold Ca2+ currents, that can be described as T-like. I(BaS) appears to correspond to a Ca2+ current with a broad activation range, which can be described as L-like. Cd2+ (100 microM) selectively blocks spike-mediated synaptic transmission between heart interneurons without significantly interfering with low-threshold Ca2+ currents and plateau formation in or graded synaptic transmission between heart interneurons. Blockade of spike-mediated synaptic transmission between reciprocally inhibitory heart interneurons with Cd2+ (150 microM), in otherwise normal saline, prevents the expression of normal oscillations (during which activity in the two neurons consists of alternating bursts), so that the neurons fire tonically. We conclude that graded and spike-mediated synaptic transmission may be relatively independent processes in heart interneurons that are controlled predominantly by different Ca2+ currents. Moreover, spike-mediated synaptic inhibition appears to be required for normal oscillation in these neurons.
Action Potentials↗
Lumbosacral plexus: a histological study.
Two hundred and forty histological paraffin sections were obtained from the midportion of the spinal nerve roots of 20 lumbosacral plexus (from L4 to S3) bilaterally. All microscopic images were digitized using the NIH image software with a Nikon microscope and Sony videocamera. The total, fascicular as well as epineurial cross-sectional areas of the nerve roots in the lumbosacral plexus were determined. The total cross-sectional area of the lumbosacral trunk (LST) was the largest (28.56 +/- 12.28 mm2) followed by the S1 (21.97 +/- 11.22 mm2) and L5 (21.00 +/- 8.79 mm2) nerve roots. The total cross-sectional areas of the L4 (6.93 +/- 3.32 mm2), S2 (13.93 +/- 5.86 mm2) and S3 (6.03 +/- 3.74 mm2) were significantly lower. Statistical differences were found among all absolute values at different levels (p < 0.0001) with the exception of the levels between L4 and S3, L5 and S1, and LST and S1 (p > 0.05). The total areas occupied by the fascicles in L5 (7.78 +/- 3.26 mm2), LST (9.97 +/- 4.01 mm2) and S1 (8.55 +/- 3.27 mm2) nerve roots were greater than those in L4 (2.96 +/- 1.50 mm2), S2 (5.56 +/- 2.34 mm2) and S3 (2.28 +/- 1.14 mm2). However, the percentages of the total cross-sectional areas occupied by the fascicles in the L5 nerve root (38%) and LST (36.4%) were smaller compared to other nerve roots (44.9% at L4, 40.5% at S1, 40.8% at S2 and 41.6% at S3). The cross-sectional areas and percentages of the epineurium were greater in L5 (13.22 +/- 6.48 mm2, 62.0%), LST (18.58 +/- 9.31 mm2, 63.6%) and S1 (13.42 +/- 8.88 mm2, 59.5%) roots. The L5 (12.1 +/- 5.0), LST (27.5 +/- 11.4) and S1 (15.0 +/- 7.3) roots contained more fascicles than L4 (6.3 +/- 3.3), S2 (9.5 +/- 4.1) and S3 (7.1 +/- 2.7). Statistical differences were found among all absolute values at different levels (p < 0.0001) with the exception of the levels between L4 and S3, L5 and S1 and LST and S1 (p > 0.05). No statistical differences were found for percentages among different levels (p > 0.05) with the exception of the levels between L4 and L5, L4 and LST, LST and S1, LST and S2, and LST and S3 (p < or = 0.05). The histological structure of nerve roots of the lumbosacral plexus is identical to that of the peripheral nerve. The midportions of L5 and S1 roots and the LST have a relatively higher epineurial content. These nerve roots also have a greater number of the fasicles, but the total cross-sectional area occupied by the fascicles is less than in L4, S2 and S3 nerve roots.
Adult↗
Cartilage and synovium of the human atlanto-odontoid joint. An anatomic and histological study.
The surface area, thickness and composition of articular cartilage of the atlanto-odontoid joints were investigated in twenty human cadaveric cervical spine specimens. The specimens were also examined grossly and by light microscopy to determine the location of the synovium. The anterior arch of the atlas and ventral and dorsal articular surfaces of the dens were covered with hyaline cartilage. The mean values of the articular surface areas on the ventral surface of the dens and anterior arch of the atlas were 55.10 and 58.24 mm2, respectively. The mean thickness of the articular cartilage of the anterior arch of the atlas, ventral and dorsal surfaces of the dens was 0.80, 0.81 and 0.82 mm, respectively. Synovial membranes were associated with the joint capsules and surrounding tissues of both anterior and posterior atlanto-odontoid joint spaces, where the synovial membranes were attached to the margins of the articular surfaces of the dens and anterior arch of the atlas anteriorly and the region of the cruciate ligament immediately peripheral to the cartilage region apposed to the dens and dens cartilage itself, posteriorly.
Adult↗
Radiographic and computed tomographic evaluation of Lisfranc dislocation: a cadaver study.
Six cadaver feet were used for radiological and computed tomographic (CT) evaluation. The tarsometatarsal joints of each specimen were displaced dorsolaterally in successive 1-mm increments. None of the 1-mm and two thirds of the 2-mm dorsolateral Lisfranc dislocations could be visualized on routine radiographs; they could all be noted on CT scans. There was good assessment on CT scan for the extent of the minor lesions that are normally obscured by overlapping projection in routine radiographs. A Lisfranc injury that appears undisplaced on radiographs or acceptable after closed reduction may still have an unpredictable outcome because of the presence of an occult joint subluxation. CT scanning is more sensitive than radiography for detecting the minor amounts of Lisfranc displacement. If there is any doubt on the radiographs, a CT scan should be performed. The early diagnosis and treatment of Lisfranc injuries may minimize development of post-traumatic degenerative arthritis.
Adult↗
Radiographic and CT evaluation of tibiofibular syndesmotic diastasis: a cadaver study.
Twelve cadaver lower limbs were used for radiographic and CT assessment of the tibiofibular syndesmosis. Plastic spacers were placed in the distal tibiofibular intervals of each specimen in successive 1-mm increments until diastasis could be appreciated on the plain radiographs. All 2- and 3-mm diastases could be noted and clearly identified on CT scans, while the 1-, 2-mm, and half of the 3-mm syndesmotic diastases could not be appreciated with routine radiographs. CT scanning is more sensitive than radiography for detecting the minor degrees of syndesmotic injuries. Therefore, a CT scan can be performed in cases of syndesmotic instability after ankle injuries and for preoperative or postoperative evaluation of the integrity of the distal tibiofibular syndesmosis in cases of doubtful condition of the syndesmosis.
Cadaver↗
Simultaneous shotgun sequencing of multiple cDNA clones.
This study describes an efficient method for the rapid sequencing of DNA fragments in the size range 1-5 kb. Individual fragments, here cDNA inserts, are purified by restriction enzyme digestion and gel purification, pooled and concatenated by ligation. The concatamers are sheared and cloned randomly into M13, followed by random sequencing. The sequences of the individual cDNA inserts are obtained at the assembly stage using restriction enzyme sites as "tags' for the ends of each fragment. In this study the sequencing of two libraries containing 7 and 16 cDNA inserts with an average length of 2.5 kb is described. The results show that of the shotgun sequencing of large fragments, and that the method compares favorably to alternative strategies, such as primer walking.
Animals↗
[24 hours ambulatory blood pressure in impaired glucose tolerance patients].
We investigated the change of 24 hours ambulatory blood pressure (ABPM) in impaired glucose tolerance (IGT) patients. 40 IGT patients were divided into two group: normotension and hypertension groups. Each group was matched with normal glucose tolerance (NGT) and non-insulin-dependent diabetes mellitus (NIDDM) group. All the patients were subjected to ABPM and biochemical index examination. The profile of ABPM in IGT patients with or without hypertension was investigated. The change of the 24 hours blood pressure in both normotensive and hypertensive IGT patients was similar with NGT, but there was a tendency that night blood pressure was increased and nocturnal blood pressure was decreased in IGT. The change of ABPM in those with abnormal circadian rhythm was elevated night blood pressure.
Adult↗
Treatment of acute pancreatitis with liyi tang--a report of 50 cases.
Fifty cases of acute pancreatitis (AP) were treated with LIYI TANG (Decoction for AP) as the treatment group, and the other 50 cases of the disease with Western drugs as the control group. The results of one-week clinical observation showed that, in the treatment group, 43 cases were cured, 3 markedly effective, 2 improved and 2 ineffective; while in the control group, 32 cases were cured, 5 markedly effective, 4 improved, and 9 ineffective, showing a statistically significant difference in therapeutic effects between the two groups (P < 0.05).
Acute Disease↗
[Study on small hepatocellular carcinoma: a review of 20 years experience].
Explore the source record for details and available documents.
Carcinoma, Hepatocellular↗
[Experimental and clinical study on gastroesophagostomy after cardiectomy of gastric stump].
60 hybrid dogs, divided into 2 groups, were subjected to subtotal gastrectomy in B-I and B-II pattern respectively. 20 weeks later, resection of cardia and fundus ventriculi and the gastric remnant esophagus anastomosis was performed. There were more omentum blood vessel embedments about the gastrojejunostomic and gastroduodenostomic stoma and collateral circulation was plentiful. In 1980, there were 25 patients with cardiac cancer of the gastric stump with an average period of 13 years and 3 months following subtotal gastrectomy and a mean age of 59.1 years. 19 patients were subjected to exploratory thoractomy, 17 resection of cardia and fundus of gastric stump and gastroesophagostomy (9 to tunnel gastroesophagostomy and 8 end-to-side esophagogastrostomy). The largest tumor was 5 cm x 4 cm. Except for a death due to intestinal obstruction following operation, the others attained a good recovery. Resection of cardia and fundus of gastric stump and gastroesophagostomy can be carried out for patients with cardiac cancer for gastric stump, which is in line with the principle of conservation surgery.
Adenocarcinoma↗
[The relationship between female infertility and genital inflammation of Chlamydia trachomatis].
To address the relationship between female infertility and genital inflammation of chlamydia trachomatis (CT), we took samples from the cervix and fallopian tube of 147 cases of female infertility and investigated the rate of CT infection by using polymerase chain reaction (PCR) assay. 60 cases of normal pregnant women were chosen as controls. The results showed that in the infertile group the CT positive rates for fallopian tubes and cervices were 15.66% and 22.45% respectively, whereas in the control group the tubal positive rate was 3.33%. There was significant difference between the two groups in tubal positive rate (P < 0.05). Youngsters and workers were the high risk population of genital infection of CT. These results indicate that genital infection of CT is an important factor causing infertility; in that disease, the tubal infection of CT is even more important. Besides the damage to tubal mucosa and smooth muscle, CT infection causes tubal adhesion and obstruction. As a result it impairs the function of the fimbriae and leads to infertility.
Adult↗
[Laboratory study on pharmacology of Chinese medication qizhi weitong powder].
The Chinese medication Qizhi Weitong Powder has been proved very helpful in depressing gastric evacuation and small intestinal propel reducing gastric secretion, lowering acidity of gastric liquid and activity of pepsin as well as enhancing peristalsis of domestic rabbits. Other effects such as distinct protection to ligated ulcer of pylorus and painkilling have also been confirmed.
Animals↗
Study on small hepatocellular carcinoma and its extension.
This paper summarizes the "study on small hepatocellular carcinoma and its extension" in Liver Cancer Institute, Zhongshan Hospital of Shanghai Medical University during the past 25 years. The results indicated that it was an important approach to obtain long-term HCC survivors, of the 239 patients with 5-year survival, small HCC resection accounted for 51.4%. It was an effective approach to improve the prognosis of HCC in the entire series, the 5-year survival of inpatients treated in authors' institution was 4.8% in 1958-1970, 12.2% in 1971-1983, and 46.7% in 1984-1995; which were correlated to the increase proportion of small HCC resection in the series; it was more effective as compared to large HCC resection, the 5 year survival was 61.3% (n = 645) versus 33.6% (n = 950). Extensions of small HCC study included early detection and treatment of small recurrent HCC, of the 147 patients with re-resection, the 5-year survival was 48.9% calculated from the time of first resection. Another extension was conversion of large HCC into small HCC, using multimodality combination treatment, 72 out of the 663 patients with surgically verified unresectable HCCs have been converted to resectable, 5-year survival being 62.1%, which was comparable to that of small HCC resection. Studies on related basic aspect of small HCC such as cell origin of recurrence, and molecular aspect of small HCC, indicated that biological characteristics, particularly the tumor invasiveness, remained the key link for further prolong survival after small HCC resection. Recently, a "patient-like" human HCC metastatic model in nude mice has been established. Experimental interventions have also been tried. Clinical trials for prevention of recurrence after small HCC resection have shown preliminary encouraging results. However, the "cost-effectiveness" of screening, the invasiveness of HCC, the multicentric origin, the coexisted Child C cirrhosis, etc., remained great challenge.
Animals↗
[The design and application of a computer aided system for measuring the electroencephalographic effect].
A new computer system (including hardware and software design) was developed which could be used to record and analyze the electroencephalographic (EEG) signal. The EEG analog signal of four channels was first digitized at a sampling rate of 960 Hz through analog to digital converter and then stored in the Sun-386 computer for off-line analysis. Various EEG effect parameters were then generated from the aperiodic waveform analysis files, i.e., total number of waves/s and total voltage/s in various frequency ranges 1-3, 4-7, 4-11, and 12-30 Hz. From various EEG parameters derived from computer system, the total number or voltage in 12-30 Hz (TNW12-30, TV12-30) was considered as the best descriptor of EEG effect.
Anti-Anxiety Agents↗