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Biomedical subjects

S Hou

Publications and source records attributed to S Hou.

At least 91 records · Page 5Linked to original sources
PubMed1999

Constitutive expression of interleukin 4 in vivo does not lead to the development of T helper 2 type CD8+ T cells secreting interleukin 4 or interleukin 5.

Interleukin 4 (IL-4) has been shown to commit CD8+ T cells to a T helper (Th) 2 functional phenotype in vitro. To study the effects of IL-4 on CD8+ T cell development in vivo we analysed the CD8+ T cell phenotype in mice constitutively expressing IL-4. Purified CD8+ T cells from uninfected or flu infected IL-4 transgenic (tg) animals produced no detectable IL-4 or IL-5 after in vitro stimulation on anti-CD3 coated plates. However, CD8+ T cells from IL-4 tg mice could be converted into IL-4 and IL-5 producers in vitro in the presence of exogenous added IL-4, showing that these cells were still responsive to IL-4. IL-4 tg mice also showed a delay in influenza virus clearance from the lung, which was probably due to the observed reduction of total CD8+ T cell numbers in the IL-4 tg animals since IL-4 tg CD8+ T cells showed normal levels of influenza-specific cytotoxicity in comparison to controls. Taken together these results suggest that CD8+ T cells are not necessarily switched to a Th2 phenotype by the presence of IL-4 and that some other factor(s) may be important in the switch process of CD8+ T cells in vivo, since the addition of IL-4 during CD8+ T cell activation in vitro leads to Th2 type CD8+ T cells secreting IL-4 and IL-5.

Animals↗
PubMed1999

Pregnancy in chronic renal insufficiency and end-stage renal disease.

Childbearing is important to women with renal disease, but pregnancy has generally been regarded as very high risk in these women. In this review, an attempt is made to clarify the nature and severity of those risks in the settings of chronic renal insufficiency and end-stage renal disease, including dialysis patients and transplant recipients. Hypertension is the most common life-threatening problem in all three groups. A wide range of antihypertensive medications have been used, with angiotensin-converting enzyme inhibitors the only drugs absolutely contraindicated because of their association with neonatal anuria, pulmonary hypoplasia, and neonatal death. Women with serum creatinine levels of 1.4 mg/dL or greater are at risk for accelerated loss of renal function compared with women who don't become pregnant. Transplant recipients have a risk for loss of renal function similar to controls as long as renal function is well preserved. The frequency of conception is decreased in women with renal insufficiency and markedly decreased in dialysis patients (0.5% per year). Return of fertility is the rule in transplant recipients. Exposure to immunosuppressive drugs, including prednisone, azathioprine, cyclosporine, and tacrolimus, has not been associated with an increase in congenital anomalies. These drugs, particularly cyclosporine, have been associated with small-for-gestational-age babies. Transplant recipients are at risk for infections that have implications for the fetus, including cytomegalovirus, herpes simplex, and toxoplasmosis. All groups have an increased risk for prematurity and intrauterine growth restriction. The percentage of pregnancies resulting in surviving infants in women with renal insufficiency and transplant recipients ranges from 70% to 100%. For women who conceive after starting dialysis, the likelihood of a surviving infant is approximately 50%.

Delivery, Obstetric↗
PubMed1999

Spectroscopic characterization of two soluble transducers from the Archaeon Halobacterium salinarum.

In the present study, structural aspects of the two soluble transducers, HtrX and HtrXI, from the archaeon H. salinarum have been examined using UV circular dichroism and steady-state fluorescence spectroscopies. Circular dichroism (CD) data indicate that both HtrX and HtrXI exhibit salt-dependent protein folding. Under low-ionic-strength conditions (0.2 M NaCl or KCl) the CD spectra of HtrXI is similar to that of the Gdn-HCl- or urea-denatured forms and is indicative of random coil structure. In contrast, the CD spectrum of HtrX under low-ionic-strength conditions contains roughly 85% alpha-helical character, indicating a significant degree of folding. Addition of NaCl or KCl to solutions of HtrX or HtrXI results in CD features consistent with predominately alpha-helical character (>95%) for both proteins. In addition, the transition points (i.e., ionic strengths at which the protein converts from random coil to alpha-helical character) are quite distinct and dependent upon the type of salt present (i.e., either NaCl or KCl). Accessibility of tryptophan residues to the solvent was also examined for both HtrX and HtrXI in both folded and unfolded states using KI quenching. The Stem-Volmer constants obtained suggest that the tryptophans (Trp35 in HtrX and both Trp47 and Trp74 in HtrXI) are partially exposed to the solvent, indicating that they are located near the surface of the protein in all three cases. Furthermore, fluorescence quenching with the single Trp mutants Trp74AIa and Trp47AIa of HtrXI indicates different environments for these two residues.

Archaeal Proteins↗
PubMed1999

Gene polymorphisms of the renin-angiotensin system in essential hypertension.

OBJECTIVE: To determine whether angiotensin-converting enzyme (ACE) gene, angiotensinogen (AGT) gene and angiotensin II receptor 1 (AT1R) gene are implicated in Chinese essential hypertension (EH). METHODS: The case-control and haplotype-based haplotype relative risk (HHRR) study consisted of 169 essential hypertensive subjects (HT), 152 normotensive controls (NT) and 62 families. The polymorphisms of insertion/deletion (I/D) allele of ACE gene and the microsatellite allele of AT1R gene were determined in DNA extracted from peripheral blood leukocytes by polymerase chain reaction (PCR). The variants of AGT gene were screened by PCR-single strand conformation polymorphism (PCR-SSCP) analysis and further identified by cloning and sequencing. RESULTS: The significant association between EH and D allele of ACE gene was found (P < 0.05). The difference of the microsatellite allele distribution of AT1R gene between HT and NT groups was statistically significant (P < 0.005). By contrast, the distribution of A-20C genotype of AGT gene was almost identical in HT and NT groups. No significant linkage disequilibrium was observed between A-20C and M235T in AGT gene. CONCLUSIONS: D allele of ACE gene might correlate with a predisposing factor for EH. The microsatellite allele of AT1R gene might be linkage disequilibrium with an unidentified variant that contributes to the development of EH. A-20C of AGT gene is not a major genetic determinant of EH.

Adult↗
PubMed1999

[The characteristics and management of shotgun wounds of the extremities].

OBJECTIVE: To discuss the characteristics, classification and the problem of management for shotgun wounds of the extremities. METHODS: 82 shotgun wounds of the extremities, classified according to the modified rule form Sherman and Ordog's, were treated by "incision and drainage" initially, and were closed in primary, delay and later phase. The fractures were fixed by plaster, external fixator, simple internal fixator or plate fixation. Vascular injury was repaired by suture end-to-end or autograft. The injured nerves were treated in the primary or later period. RESULTS: The rate of infection was the highest in the primary closed wound, and the healing time was the longest in the later closed wound. The rate of infection was much higher in the fracture fixed by plate than the others. The results of nerve recovery in primary repair were not significantly different (except 2 case infection) from those in the later repair. CONCLUSIONS: A significant difference was noted between shotgun wound and other wound. Removal of wadding, prevention of fascial compartment syndrome, repeat planned exploration of wound, proper wound closing, external fixation of fracture, vascular debridement before anastomosis and delayed nerves repair contribute to a successful outcome in patients with extremity shotgun wounds.

Adolescent↗
PubMed1999

[The application of BTA stat in the diagnosis of bladder tumor and hematuria].

OBJECTIVE: To analyze the value of the Bard BTA Stat for the diagnosis of bladder tumor and hematuria in order to find a new, noninvasive examination method. METHODS: BTA Stat, an one step monoclonal antibody immunofluorescence analysis that qualitatively detects the presence of bladder tumor associated antigen (hCFHrp), was used. 65 patients with hematuria, 71 patients with bladder transitional cell carcinoma, and 10 normal people underwent voided urine BTA Stat analysis. RESULTS: The specificity of the technique for patients with bladder transitional cell carcinoma and hematuria was 84.6% and 31.1% respectively, with a sensitivity of 73.7% and 90.0% respectively. CONCLUSIONS: BTA Stat was considered a convenient, rapid and noninvasive method in the diagnosis of bladder tumor. However, the results were interfered by the presence of erythrocyte in urine, infection, urinary lithiasis. This method is proved to be useful in the surveillance of bladder tumor.

Adult↗
PubMed1999

[Primary shortening followed by bone lengthening in situ for the treatment of gunshot bone defect].

OBJECTIVE: To study the treatment of gunshot bone defect and the biological basis of primary shortening followed by callus distraction in situ. METHODS: The canine with gunshot bone defect were treated by two methods, primary shortening followed by callus distraction or delayed bone graft. The local blood flow and pathomorphological change were observed and compared with each other. RESULTS: In the experiment, the bone lengthening was stopped at the 56th day with (2.82 +/-e 0.94) cm (19.3%) gain in the group of bone lengthening, and the time of bone healing was much shorter in the group of bone lengthening than in the group of delayed graft. There was no significant difference between the groups in the time of soft tissue healing and local blood flow. CONCLUSIONS: The technique of primary bone lengthening is simple and has no side effect on tissue healing and local blood flow.

Animals↗
PubMed1998

Registry of pregnancy in dialysis patients.

A total of 2,299 dialysis units listed by the Health Care Finance Administration were surveyed to determine the frequency and course of pregnancies in dialysis patients. The responses included 930 units caring for 6,230 females aged 14 to 44 years (1,699 receiving peritoneal dialysis and 4,531 receiving hemodialysis). Two percent of the female patients of childbearing age became pregnant over a 4-year period (2.4% of the hemodialysis patients and 1.1% of the peritoneal dialysis patients). The infant survival rate was 40.2% in the 184 pregnancies in women who conceived after starting dialysis and 73.6% in the 57 pregnancies in women who started dialysis after conception. In the subset of women in whom dialysis modality was known, infant survival was not significantly different between the hemodialysis and peritoneal dialysis patients (39.5% v 37%). There was a trend toward better infant survival in women who received dialysis > or = 20 hours per week and a weak correlation between number of hours of dialysis and gestational age (P = 0.05). Maternal complications included two maternal deaths and five intensive care unit admissions for hypertensive crisis. Seventy-nine percent of women had some degree of hypertension, and 32 had blood pressure higher than 170/110 mm Hg. Only 5.9% of women had a hematocrit greater than 30% throughout pregnancy. Twenty-six percent of women treated with erythropoietin (EPO) and 77% of women not receiving EPO required transfusions. Eleven infants had congenital anomalies and 11 had long-term medical problems. Eighty-four percent of infants born to women who conceived after starting dialysis were premature. The likelihood of a surviving infant resulting from pregnancy in dialysis patients is higher than previously observed. There is no preferred dialysis modality. There is a suggestion that increased dialysis time may improve outcome. Prematurity remains a major cause of morbidity and likely contributes to a high frequency of long-term medical problems in surviving infants.

Adolescent↗
PubMed1998

Management of the pregnant dialysis patient.

In this report, the outcome, diagnosis, management, and complications of pregnancy in dialysis patients are discussed. The advantages and disadvantages to the use of peritoneal dialysis and hemodialysis and the changes in dialysis regimen used in pregnant women are addressed. Maternal complications, particularly hypertension and anemia, are reviewed. This report looks at the approach to the management of anemia and calcium/phosphorus metabolism in the setting of limited information. The report also discusses pregnancy outcome for the mother and fetus, including the problem of prematurity and fetal loss. Special considerations in women with lupus and diabetes are noted. Pregnancy in dialysis patients remains a high-risk undertaking for both the patient and the infant. There are large gaps in our knowledge base regarding the effect of the abnormalities associated with renal failure on pregnancy. The survival of the infant and the safety of the mother depend on close cooperation among all the specialities involved, including nurses, doctors, nutritionists, and social workers from nephrology, perinatology, and neonatology.

Adult↗
PubMed1998

Sensory rhodopsin II transducer HtrII is also responsible for serine chemotaxis in the archaeon Halobacterium salinarum.

Previously, we demonstrated that the methyl-accepting protein HtrII is the transducer for photoreceptor sensory rhodopsin II. Here, we provide experimental evidence that HtrII is also a chemotransducer. Using an agarose-in-plug bridge method, we show that an HtrII overexpression strain has a quicker response to serine than does an HtrII deletion strain. Furthermore, an in vivo flow assay demonstrates that the deletion strain is unable to modulate methylesterase activity after serine addition or photostimulation, while the overexpression strain shows distinct methanol peaks following both types of stimuli.

Archaeal Proteins↗
PubMed1998

[Separation and determination of eight plant hormones by reversed-phase high performance liquid chromatography].

In this paper, reversed-phase high performance liquid chromatographic technique was used for the separation and determination of eight plant hormones. Methanol-water-acetic acid system was chosen as the mobile phase. The effects of different separation conditions, such as the methanol and acetic acid concentrations in mobile phase, on the retention behaviours of eight plant hormones in this system were studied. The general trends in retention behaviours could be correlated to the methanol concentration in mobile phase. The experimental results showed that the optimum separation was achieved with following gradient elution condition: 0-3 minutes, 70% (water percentage in mobile phase), 3-13 minutes, 70%-20%, 13-48 minutes, 20%. Benzene was added to be as the internal standard. Under this experimental condition, the eight plant hormones could be separated completely and detected quantitatively at 260 nm within 16 minutes. The calibration curves for the eight compounds gave linearity over a wide range. The correlation coefficients of each components were r(ZT) = 0.9971, r(GAs) = 0.9999, r(K) = 0.9997, r(BA) = 0.9995, r(IAA) = 0.9998, r(IPA) = 0.9982, r(IBA) = 0.9995 and r(NAA) = 0.9995. The method is rapid, simple and efficient. It is a suitable method for the accurate determination of gibberellic acid (GA) and alpha-naphthaleneacetic acid (alpha-NAA) in products for agricultural use.

Chromatography, High Pressure Liquid↗
PubMed1998

[Compatible leaching effect of Concha Ostreae and some commonly-used Chinese medicinal materials].

OBJECTIVE: Based on a study of Concha Ostreae, to provide some reference for the rational approach to leaching mineral drugs. METHOD: Taking the change rates of compatible leaching and value of A as targets, the compatible leaching effect of Concha Ostreae with Radix et Rhizoma Rhei Praeparata, Radix Scutellariae, Pollen Typhae and Fructus Aurantii lmmaturus was studied. RESULT: If Concha Ostreae and the above cited medicinal herbs are decocted together, the yield of extract may be reduced to a certain extent, but the target composition of Radix et Rhizoma Rhei Praeparata and Fructus Aurantii lmmaturus remains intact, only the content of Radix Scutellariae baicalin may be influenced. CONCLUSION: The relationship of technology with preparation must be taken into consideration when making choice of the proper way to leach Concha Ostreae.

Animals↗
PubMed1998

[Fatal complications in traffic accident injury].

OBJECTIVE: To discuss the relative factor, development tendency and prevention of the fatal complications in traffic accident injury. METHOD: We observed injury severity scale (AIS-ISS), clinical response time, and occurrence in traffic accident injury with fatal complications. Ridit mathematical statistics and Q test were used. RESULT: There were high ISS and long clinical response time in traffic accident injury with fatal complications. A significant relation was found between complications and the progress of time after trauma, thereby the clinical course could be divided into phases of cerebral hernia and shock (or acute), transition, infection and multiple organ dysfunction syndrome (MODS). There was higher head AIS in the cerebral hernia. ISS of shock patients was significantly higher than that of the others. Massive infections occurred in the patients with extremity trauma. There was a significant relation between the occurrence of MODS and infection. CONCLUSION: The occurrence of fatal complications is related to the location and severity of injury in traffic accident injury. A regularity is present in the occurrence of fatal complications with time progress.

Abbreviated Injury Scale↗
PubMed1998

[The relationship of facet orientation to intervertebral disc protrusion and lateral recess stenosis in lower lumbar spine].

OBJECTIVE: To investigate the relationship of facet orientation to intervertebral disc protrusion and lateral recess stenosis in lower lumbar spine. METHOD: The relationship between facet geometry (joint angle and tropism) and disc protrusion, lateral recess stenosis was investigated with computer tomography (CT) at the vertebral levels L(3 - 4), L(4 - 5), and L(5) - S(1). 772 facet joint angles (386 lower lumbar levels of 136 patients) were measured on coronal CT scans by transverse inter-facet angle (TIFA). RESULT: There was no statistically significant relationship between facet joint asymmetry and disc protrusion (P > 0.05). Disc protrusion occurred more frequently on side of sagittally oriented facet joint than coronal side (P < 0.01). The patients whose lumbar transverse inter-facet angle less than 20 degrees easily suffered from degenerative lumbar lateral recess stenosis in the elderly. The TIFA in Asian less evident than in European may be the important cause for high incidence of lumbar lateral recess syndrome in Asia. CONCLUSION: Stress on the lower lumbar spine leads to disc protrusion. No association is found between facet joint asymmetry and lumbar disc protrusion. The asymmetry of facet joint will influence the direction of intervertebral disc protrusion at level from L(4) - S(1). The patient whose lower lumbar spine inter-facet angle may unlikely suffer from degenerative lumbar lateral recess stenosis.

Adolescent↗
PubMed1998

[Subpopulations of TIL in renal cell carcinoma and their clinical significance].

OBJECTIVE: To study the relationship between tumor-infiltrating lymphocytes (TIL) and the prognosis of patients with renal cell carcinoma. METHOD: Immunohistological chemistry method was employed to semiquantitatively assess the expression of TIL and its subpopulations. The prognostic values of various TIL subpopulations were also evaluated. RESULT: T-lymphocyte was the main component of TIL, B-lymphocyte, monocyte, and nature killer (NK) cells were also presented but in relatively small numbers. T-lymphocyte was strongly correlated to the survival probability, but this correlation was not observed between the host survival and TIL or other subpopulations. CONCLUSION: T-lymphocyte can represent the host immunological status and can be used to judge the prognosis of patients with renal cell carcinoma.

Adult↗
PubMed1998

[Clinical study on traumatic anterior instability of shoulder].

OBJECTIVE: To study the clinical diagnosis, conservative and surgical treatment of traumatic anterior instability of the shoulder. METHOD: Based on the experience in diagnosis and treatment of 41 patients, we put forward criteria for diagnosis and treatment of traumatic anterior instability of the shoulder. RESULT: Diagnostic criteria: (1) history of injury to the shoulder; (2) sharp pain in the anterior aspect of the shoulder and weakness and limitation of range of motion of the shoulder; (3) the positive apprehension sign and or anterior drawer test; (4) a Hill-Sachs bony lesion on roentgenogram and abnormal double contrast CT. TREATMENT: (1) rehabilitation program for the patients having symptoms less than 3 months and without anterior capsular rupture; (2) capsular repair and imbrication procedure for the patients having symptoms more than 3 months, or not satisfied to the rehabilitation treatment, or severe anterior capsular rupture on double contrast CT. The results of the treatment were satisfactory with average 16-month follow-up. CONCLUSION: The diagnostic criteria and the treatment principles help improve the results of treatment of shoulder injuries, further clinical study is needed for traumatic anterior instability of the shoulder.

Adult↗
PubMed1998

[Effect of calmodulin inhibitor on spinal cord injury].

OBJECTIVE: To evaluate the effect of a special calmodulin (CaM) inhibitor-trifluoperizine (TFP) on spinal cord injury (SCI) and the role of CaM in SCI. METHOD: We observed the effect of TFP on spinal cord blood flow (SCBF), motor evoked potentials (MEP) and motor function in SCI by using hydrogen clearance, inclined plane and electro physiological technique. RESULT: There was significant improvement of SCBF, MEP and motor function with TFP, when adrenaline maintained the system arterial pressure in SCI. CONCLUSION: Prevention by TFP of spinal cord function in SCI suggested that CaM plays a role in the pathogenesis of SCI.

Animals↗