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H H Lin

Publications and source records attributed to H H Lin.

At least 145 records · Page 8Linked to original sources

The helix-loop-helix proteins (salivary-specific cAMP response element-binding proteins) can modulate cAMP-inducible RP4 gene expression in salivary cells.

Salivary-specific and cAMP-inducible expression of the rat proline-rich protein gene RP4 is dependent on a 28-base pair sequence of a salivary-specific cAMP response element (SCRE) (Lin, H. H., and Ann, D. K. (1992) Gene Expression 2, 365-377). To unravel its trans-acting factor(s), we used double-stranded oligoprobes corresponding to the SCRE to screen a randomly primed lambda gt11 cDNA expression library made from RNA of rat salivary cells. In this report, we describe the cDNA cloning of these helix-loop-helix SCRE-binding proteins (SCBPs) and demonstrate that there are at least three isoforms in salivary cells, namely SCBP alpha, SCBP beta, and SCBP gamma. RNA polymerase chain reaction and sequence analyses further confirmed the existence of these three different SCBP isoforms, which code for putative proteins of 707, 706, and 682 amino acids, respectively. Expression of the cloned SCBP cDNAs in salivary cells stimulates the expression of a cotransfected reporter construct containing multicopies of the SCRE cloned upstream of the thymidine kinase promoter and the chloramphenicol acetyltransferase structural gene. This stimulation is much more pronounced in transfections in which SCBP alpha and SCBP beta are cotransfected than when they are transfected individually. Furthermore, when low concentrations of SCBP alpha and SCBP beta are cotransfected with the SCRE reporter gene, coexpression of the catalytic subunit of protein kinase A is required to efficiently activate the expression of the reporter gene. These results strongly suggest that the observed stimulation of the SCRE is achieved through the coordinated expression of the SCBP alpha, SCBP beta, and protein kinase A activities, perhaps via a direct association of the two SCBPs and their phosphorylation by protein kinase A. We conclude that the isolated SCBP alpha and SCBP beta cDNAs encode transcription activators that participate in the control of the inducible RP4 gene expression in salivary cells.

Amino Acid Sequence↗

High incidence of hepatitis C virus infection in hemodialysis patients in Taiwan.

A longitudinal follow up of 202 hemodialytic patients were conducted to evaluate the incidence of hepatitis C virus (HCV) infection in this high-risk group. A total of 113 patients were found to be seronegative for anti-HCV at the start of this study period. During the average follow-up period of 39 months, 51 patients developed anti-HCV later (group I), while the remaining 62 patients (group II) were seronegative throughout the study period. The results showed that the incidence of HCV seropositivity is 14.6% per year. Longer periods of hemodialysis and younger age of the patient, but not reuse of dialyzer or sex, were correlated with a higher positive rate of anti-HCV. Clinical hepatitis episodes occurred more frequently in group I (56.9%), while persistently normal alanine aminotransferase (ALT) was observed more often in group II (54.8%). There was no significant changes in hepatitis B surface antigen (HBsAg). A total of 41 patients developed hepatitis among the 59 patients who received transfusions, but there was no significant difference between the two groups. We conclude that HCV infection is the main cause of hepatitis in hemodialysis. The longer the patient underwent hemodialysis, the higher the anti-HCV positive rate became, which did not seem to be related to transfusions. Once infected, there is a low disappearance rate of anti-HCV. The exact route of transmission awaits further investigation.

Adolescent↗

Hepatitis B virus in the colostra of HBeAg-positive carrier mothers.

To investigate the amount of hepatitis B virus (HBV) in colostra of hepatitis B e antigen (HBeAg)-positive carrier mothers and the relationship of HBV amount between colostrum and maternal blood, 50 HBeAg-positive carrier mothers were recruited and studied for hepatitis B surface antigen (HBsAg) titer, HBeAg titer, and HBV-DNA concentration in their sera and colostra. According to the presence or absence of seral HBV-DNA determined by dot hybridization, these 50 HBeAg-positive carrier mothers could be divided into two groups: group 1 (n = 28, HBV-DNA < 0.04 ng/ml), and group 2 (n = 22, HBV-DNA > or = 0.04 ng/ml). The colostral HBsAg and HBeAg titers were both significantly higher in group 2 than in group 1. In addition, both colostral HBsAg and HBeAg titers had positive correlation with each corresponding maternal blood. Although the colostral HBV-DNA was undetectable by dot hybridization, all were positive by polymerase chain reaction with Southern blot hybridization. Because HBV-DNA can be detected in all HBeAg-positive carrier mother's milk, it reinforces the necessity of hepatitis B vaccination for the neonates born to these carrier mothers, particularly in countries with a high carrier rate.

Base Sequence↗

Comparison of three different immunoassays and PCR for the detection of hepatitis C virus infection in pregnant women in Taiwan.

To compare different hepatitis C virus (HCV) immunoassays and HCV-RNA in pregnant women, we investigated two independent groups: 1,687 cases without screening for serum alanine aminotransferase (ALT) (group A) and 333 cases with elevated ALT (> 45 IU/l) (group B), after screening 21,459 pregnant women. In group A, 11 (0.65%) and 21 (1.24%) were anti-HCV-positive by first- and second-generation tests, respectively, while in group B 8 (2.40%) and 19 (5.71%) were positive, respectively. The results revealed by second-generation assays based on either recombinant protein or synthetic peptides were identical, as were the anti-HCV titers in group B. Among 40 second-generation anti-HCV-positive cases, 18 (86%) of 21 in group A and 17 (89%) of the 19 in group B contained serum HCV-RNA by RT-PCR. Thus the prevalence of anti-HCV in Taiwanese pregnant women is 1.24% versus 5.71% in those with elevated ALT level.

Female↗

Macaque salivary proline-rich protein: structure, evolution, and expression.

Proline-rich proteins are a family of proteins that exhibit unique features including an unusual high proline content and salivary-specificity. As a major constituent in the salivary secretion of higher primates, proline-rich proteins may have biological roles in oral lubrication and protection. In this article, the genomic structure and regulation by cAMP of one of the macaque salivary proline-rich protein genes, MnP4, is reviewed. The evolution of this multigene family of proteins is also discussed.

Amino Acid Sequence↗

Vulvar neoplasia associated with other primary malignancies.

It is recognized that a significant number of patients with vulvar neoplasia have had previous, concurrent, or subsequent genital tract neoplasia. This has resulted in speculation that there may be a common etiology and, in particular, of the possibility of an infection element. Among 59 cases of vulvar cancer diagnosed at the National Taiwan University Hospital from 1976 to 1991, there were seven cases (12%) associated with other primary malignancies. Carcinoma of the cervix was the most frequent other primary cancer (6/7, 86%). The possible role of human papilloma virus infection in genital neoplasia is discussed.

Adult↗

Isoproterenol/tannin-dependent R15 expression in transgenic mice is mediated by an upstream parotid control region.

Transgenic mice were used to locate the cis-acting DNA elements that are essential for tissue-specific and inducible expression of the rat proline-rich protein gene, R15. Chimeric genes with up to 10 kb of R15 5'-flanking region fused to chloramphenicol acetyltransferase (CAT) or polyomaviral large T-antigen (PyLT) reporter genes were tested. Our results demonstrate that (1) the isoproterenol/tannin-inducible, parotid-specific transgene expression requires an upstream cis-regulatory domain, namely the parotid control region, which extends from -6 to -1.7 kb of the R15 gene; (2) this parotid control region functions with a heterologous promoter and is indispensable for achieving a reproducible chromosomal position-independent transgene expression; (3) deletion of the R15 5'-flanking region up to -1.7 kb results in a pleiotropic effect on the transgene expression, which includes ectopic (nonsalivary) reporter expression and lack of inducibility by either the beta-agonist isoproterenol or dietary tannin stimulation; (4) when the -10 to -6 kb region from the R15 gene is deleted in the construct, the inducible expression in the parotid glands of the transgenic mice decreases by over 30-fold, but position-independent and tissue-specific transgene expression is retained. Moreover, the mechanism of induction by either catecholamine isoproterenol or dietary tannin appears to be through a beta 1-adrenergic receptor-mediated pathway for both normal (non-transgenic) and transgenic animals.

Animals↗

Clinical study of 381 postmenopausal bleeding patients.

In order to evaluate the etiology, incidence of malignancy, clinical risk factors and the interval between menopause and the onset of abnormal vaginal bleeding in postmenopausal women, 381 cases with a complete medical history and available histologic findings were enrolled in this study at the National Taiwan University Hospital from 1989 to 1991. The results showed that 212 (55.6%) of these women had normal histologic findings and 83 (21.9%) had benign pathologic findings, whereas 14 (3.6%) had cervical intraepithelial neoplasia (CIN), 42 (11%) had endometrial hyperplasia, 19 (5%) had cervical cancer and 11 (2.9%) had endometrial cancer. Twenty-nine (7.6%) of the cases suffered from either CIN III or cervical cancer; this number was twice as high as those with endometrial atypical hyperplasia and endometrial cancer (n = 13, 3.4%). In addition, various risk factors, especially obesity, were found to be significantly correlated with malignancy. Fractional curettage should be performed for postmenopausal bleeding patients to ensure accurate diagnosis and correct management.

Endometrial Hyperplasia↗

A 77-year-old man with right anterior knee pain. Intraosseous gout of the patella.

The following case is presented to illustrate the roentgenographic and clinical findings of a condition of interest to the orthopaedic surgeon. Initial history, physical findings, and roentgenographic examinations are found on the first two pages. The final clinical and roentgenographic differential diagnoses are presented on the following pages.

Aged↗

[Acute upper gastrointestinal bleeding in Chang Gung Memorial Hospital: comparison between 1980 and 1989].

Upper gastrointestinal (UGI) bleeding remains a great medical problem despite the improvement in both diagnostic and therapeutic management. We retrospectively analyzed 560 cases (male 429 cases, female 131 cases, mean age 45.8 +/- 23.1 years) of acute UGI bleeding within one year from January to December 1980, and 1872 cases (male 1395 cases, female 477 cases, mean age 48.7 +/- 27.5 years) within one year from January to December 1989, in order to define the changing pattern of etiology in the past 10 years. The major cause of bleeding was duodenal ulcer bleeding, which occurred at the age of 20-40 years. The incidence significantly decreased (57.8% in 1980 VS. 46.3% in 1989, P < 0.001). The second common cause was gastric ulcer (11.1% VS. 13.5%), which occurred mainly at the age of 50-70 years. The third was esophageal varices bleeding with a significantly increased incidence (6.6% VS. 11.4%, P < 0.001), which occurred mainly at the age of 40-60 years. The other less common causes included gastric cancer (5.9% VS. 5.8%), which occurred mainly at the age of 50-70 years, gastric erosion (5.2% VS. 6.1%), Mallory Weiss tear (2.1% VS. 3.1%), esophagitis (1.9% VS. 2.9%), Dieulafoy's ulcer (1.6% VS. 2.7%), vascular lesion (1.6% VS. 2.6%), and non-diagnostic cases (6.2% VS. 5.6%). The ratio of male to female for each etiology of UGI bleeding was about 3 to 1 in both 1980 and 1989.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Open femur fracture secondary to hippopotamus bite.

The surgical treatment of a patient who sustained a grade IIIC open femur fracture as a result of a hippopotamus bite is described. We review the available literature on large wild animal attacks to humans. A standard protocol for management of open fractures was followed in this patient, and eventually led to a good result.

Accidents, Occupational↗

Five-year experience of human immunodeficiency virus type 1 national screening program implemented at Veterans General Hospital-Taipei.

From July 1986 through June 1990, 33,199 sera from various risk groups were collected in Veterans General Hospital-Taipei for detection of antibody against human immunodeficiency virus, type 1 (HIV-1). Sixty-five samples were proved positive by Western blot analysis. Among individual high risk groups, hemophiliacs had the highest positive rate of 20/60 (29.41%), followed by homosexual/bisexual males (41/1,264, 3.24%). The overall positive rate was 65/33,199 (0.19%). Ten cases were recognized as acquired immunodeficiency syndrome (AIDS), 1 case had AIDS-related complex (ARC) and 4 case had other apparently symptomatic infections. Among these 15 cases, 7 expired, 1 lost of follow-up and 7 surviving cases are being treated with zidovudine (AZT). Most of symptomatic HIV-1 antibody positive cases had abnormal T4/T8 ratio of 0.39 +/- 0.54 as compared with the asymptomatic HIV-1 carriers at a ratio of 0.81 +/- 0.69. The opportunistic infections included Pneumocystis carinii pneumonia (PCP) in 6 case, disseminated cytomegalovirus infection in 6 cases, herpes zoster virus infection in 3 case, candidiasis in 4 cases, syphilis in 3 cases, pulmonary tuberculosis in 2 cases, and others with cryptococcosis, salmonellosis, Mycobacterium avium-intracellulare infection, gonorrhea, Staphylococcus aureus endocarditis and bacterial sepsis, etc. The natural history of HIV-1 infection to AIDS involved acute and persistent multiple infections. Although prevalence of HIV-1 infection was low in Taiwan, nationwide surveillance of HIV-1 infection in various risk groups is still needed.

AIDS-Related Opportunistic Infections↗

"Salvage" procedures in the treatment of Kienböck's disease. Proximal row carpectomy and total wrist arthrodesis.

In symptomatic stage III Kienböck's disease, proximal row carpectomy may be considered not only as a secondary "salvage," but also a primary reconstructive procedure. The need for concomitant radial styloidectomy is assessed intraoperatively after removal of the proximal row. Distraction resection arthroplasty is an alternative for patients with full-thickness cartilage loss on the capitate head or in the lunate fossa surpassing 3 mm in diameter. For patients with generalized carpal arthrosis (stage IV Kienböck's disease) or unsuccessful previous reconstructive surgeries, total wrist arthrodesis is the most reliable procedure for pain relief. PRC is an acceptable alternative to TWA for stage IV disease if the patient is willing to risk having some residual pain to preserve wrist motion. Transection of the articular branch of the posterior interosseous nerve may be a useful adjunct to these procedures.

Arthrodesis↗

Characterization of the statin-like S1 and rat elongation factor 1 alpha as two distinctly expressed messages in rat.

Previously, we reported a rat S1 protein that is antigenically related to statin, a nonproliferating cell-specific marker; however, it shares high homology with the known human elongation factor-1 alpha (EF-1 alpha). To differentiate S1 from rat EF-1 alpha and to study their respective regulation for expression, a rat EF-1 alpha cDNA clone was isolated and characterized. The nucleotide and deduced amino acid sequences of this partial rat EF-1 alpha cDNA are compared with that of human and mouse as well as with rat S1. Both their messages were detected in rat brain by EF-1 alpha- or S1-specific probes. However, the mRNA encoding EF-1 alpha is more abundant than that encoding S1. S1 and EF-1 alpha expression were investigated in the parotid and submandibular glands of untreated rats and those treated with isoproterenol, a proliferation-inducing catecholamine. Quantitative solution hybridization demonstrated a dramatic reduction (approximately 68%) in the S1 mRNA following isoproterenol injection in proliferation-responsive parotid glands and a mild reduction (approximately 20%) of S1 steady-state messages in the proliferation-refractile submandibular glands. A slight increase or no changes of EF-1 alpha levels in both parotid and submandibular glands following isoproterenol treatment are also observed. Therefore, the EF-1 alpha and S1 genes are different genes, both expressed and regulated in vivo, but in differential quantitative and qualitative patterns.

Amino Acid Sequence↗

Cellular immune response to HBcAg in mother-to-infant transmission of hepatitis B virus.

Cellular immunity to HBcAg was studied in hepatitis B virus carrier children and neonates born to hepatitis B virus carrier mothers. A significant proliferative response of peripheral blood mononuclear cells to HBcAg was found in 5 of 10 children with elevated ALT levels but in none of the nine HBeAg-positive children with normal ALT levels. HBeAg but not HBsAg was detected in cord blood of 9 of 10 neonates born to HBeAg-positive carrier mothers, suggesting exposure of these neonates to HBeAg in utero. However, cord mononuclear cells from neonates born to HBeAg-positive carrier mothers did not show a significant change in the proportion of suppressor and helper T-cell subsets or proliferative response to HBcAg. Nor did they produce interleukin-2 receptor after being cocultured with HBcAg. The unresponsiveness of peripheral-blood mononuclear cells or cord mononuclear cells to HBcAg was not reversed by CD8+ cell depletion. Although cord blood mononuclear cells from neonates born to carrier mothers positive for antibody to HBeAg also did not respond to HBcAg, we encountered an infant, born to a carrier mother positive for antibody to HBeAg, who contracted acute hepatitis B at 2.5 mo of age. The baby's peripheral-blood mononuclear cells showed a significant proliferative response to HBcAg. These results support the view that transplacental maternal HBeAg probably induces a specific unresponsiveness of helper T cells to HBcAg and HBeAg in the neonates born to HBeAg-positive carrier mothers. This specific helper T cell tolerance could be maintained throughout the early replicative phase of carrier state but might break someday with the appearance of raised ALT level.

Adolescent↗

The prognostic factors of severe amebic liver abscess: a retrospective study of 125 cases.

One hundred twenty-five cases of amebic liver abscess were diagnosed at Chang Gung Memorial Hospital in Taiwan from January 1981 to December 1989. An analysis of possible prognostic factors for severe amebic liver abscess was done retrospectively. The majority of the patients came from the southern part of Taiwan. Severe amebic liver abscess was defined as the rupture of an abscess that was resistant to 72 hr of medical treatment, or complicated by secondary bacterial infection. The results showed significant differences between patients with severe liver abscess and those with more moderate forms of amebic liver abscess in indices such as jaundice, hemoglobin and serum bilirubin levels, and dyspnea, as well as in pulmonary changes (right diaphragm elevation, right pleural effusion) seen on chest radiographs. Those patients with diabetes mellitus also had greater evidence of severe liver abscess. Moderate cases that were treated with amebicides showed excellent responses (no mortality). Severe cases required, in addition to amebicide therapy, either percutaneous or surgical drainage of pus, especially in those patients with ruptured abscesses. Those patients with abscesses that ruptured into the thoracic cavity were treated by either thoracostomy or needle aspiration, and all were cured. Three patients died of abscess rupture into the abdominal cavity, associated with secondary bacterial infection. The overall mortality rate was 2.4%. These symptoms and signs of severe liver abscess are indicators of the need for intensive treatment such as aspiration or surgical drainage.

Adult↗

Identification of cis- and trans-acting factors regulating the expression of rat salivary-specific RP4 gene.

The molecular basis of tissue-specific and cyclic AMP (cAMP)-inducible gene expression in salivary glands is not well understood. Previously, we cloned a salivary-specific proline-rich protein gene, RP4. To analyze the cis-regulatory element(s) that mediates the regulation of this rat salivary RP4 gene, chimeric pRP4CAT constructs containing up to 1.7 kb of the 5'-flanking region of RP4 fused to a reporter gene were transiently transfected into salivary cells. Deletion studies suggest that a 159 bp (-147/+12) fragment of the RP4 5'-flanking region is sufficient to confer salivary-specific induction by agents that can raise intracellular cAMP concentration. Further delineation of this essential sequence revealed that a segment from -136 to -109 is necessary and sufficient to confer cAMP responsiveness in a salivary-specific manner when linked to a heterologous promoter. However, this 28 bp fragment (-136/-109) does not contain an identical match to the consensus cAMP response element (CRE). DNA mobility shift binding assays establish that a sequence-specific DNA-protein complex is formed between this DNA fragment and nuclear proteins from salivary cells, but not with nuclear proteins from HeLa cells, which contain canonical CRE binding proteins (CREBs). Taken together, these data demonstrate that we have identified a 28 bp cis-regulatory element in the RP4 gene that mediates salivary-specific cAMP-inducible gene expression. We propose that the novel salivary-specific CRE binding protein (SCBP) is a key regulator for salivary cAMP-inducible gene expression.

Animals↗

Treatment and outcome of unexplained recurrent spontaneous abortions in subclinical autoimmune disorders.

Patients with a history of three or more fetal losses before a gestational age of 20 weeks were examined. Only patients with normal chromosomal, hormonal and anatomic findings were included in this study. These patients were tested for the antinuclear antibody, the C3 and C4 levels, anti-ENA [Ro(SSA), La(SSB), SM, RNP, scl-70], anti-single-stranded DNA and anti-double-stranded DNA, lupus anticoagulant, anticardiolipin and antiphosphotidylserine. All of these patients were free of any symptoms, except for the repeated abortions. The results showed that 10 out of 213 (4.7%) patients with unexplained recurrent spontaneous abortions had abnormal serologic tests, and 28% of the abortions (nine out of 32 abortions) occurred during the second trimester. With treatment of low-dose aspirin alone, or in combination with prednisolone, two out of 11 pregnancies in these 10 patients resulted in repeated abortions (18%), which was significantly lower than their previous abortion rate where 32 out of 33 pregnancies resulted in abortions (97%). Four babies (three term and one premature) were delivered without any abnormalities and the other five pregnancies are beyond the 28th week of gestation and are progressing smoothly. This study revealed that subclinical autoimmune disorders may play a role in recurrent spontaneous abortions and adequate treatment can improve the pregnancy outcome.

Abortion, Habitual↗