Diffraction and imaging from a beam of laser-aligned proteins: resolution limits

The effect of the limited alignment of hydrated molecules is considered in a laser-aligned molecular beam, on diffraction patterns taken from the beam. Simulated patterns for a protein beam are inverted using the Fienup-Gerchberg-Saxton phasing algorithm, and the effect of limited alignment on the resolution of the resulting potential maps is studied. For a typical protein molecule (lysozyme) with anisotropic polarizability, it is found that up to 1 kW of continuous-wave near-infrared laser power (depending on dielectric constant), together with cooling to liquid-nitrogen temperatures, may be needed to produce sufficiently accurate alignment for direct observation of the secondary structure of proteins in the reconstructed potential or charge-density map. For a typical virus (TMV), a 50 W continuous-wave laser is adequate for subnanometre resolution at room temperature. The dependence of resolution on laser power, temperature, molecular size, shape and dielectric constant is analyzed.

Iterative phase retrieval without support

An iterative phase retrieval method for nonperiodic objects has been developed from the charge-flipping algorithm proposed in crystallography. A combination of the hybrid input-output (HIO) algorithm and the flipping algorithm has greatly improved performance. In this combined algorithm the flipping algorithm serves to find the support (object boundary) dynamically, and the HIO part improves convergence and moves the algorithm out of local minima. It starts with a single intensity measurement in the Fourier domain and does not require a priori knowledge of the support in the image domain. This method is suitable for general image recovery from oversampled diffuse elastic x-ray and electron-diffraction intensities. The relationship between this algorithm and the output-output algorithm is elucidated.

Enhancement of the superconducting transition temperature of MgB2 by a strain-induced bond-stretching mode softening

We report a systematic increase of the superconducting transition temperature T(c) with a biaxial tensile strain in MgB2 films to well beyond the bulk value. The tensile strain increases with the MgB2 film thickness, caused primarily by the coalescence of initially nucleated discrete islands (the Volmer-Weber growth mode.) The T(c) increase was observed in epitaxial films on SiC and sapphire substrates, although the T(c) values were different for the two substrates due to different lattice parameters and thermal expansion coefficients. We identified, by first-principles calculations, the underlying mechanism for the T(c) increase to be the softening of the bond-stretching E(2g) phonon mode, and we confirmed this conclusion by Raman scattering measurements. The result suggests that the E(2g) phonon softening is a possible avenue to achieve even higher T(c) in MgB2-related material systems.

Evolving technique for continent ileostomy: valveless pouch design

A continent ileostomy, or Kock pouch, is a useful option for patients with inflammatory bowel disease whose only alternative is an end ileostomy. This technique has a high morbidity rate. Nipple valve slippage is the most common complication, causing incontinence or intubation problems. A novel, valveless continent ileostomy technique is described here. A porcine model was used to create the continent ileostomy. Two pouches were created and tested for integrity and continence using lactated Ringer's solution. Pouch pressure and volume were recorded in one pouch. The valveless continent ileostomy was successfully created twice, and both pouches were continent. An intraluminal pressure of 30 mmHg and a volume of 225 ml were measured in one pouch. In this preliminary report of a valveless continent ileostomy, we had promising results. The future of this technique in clinical practice needs to be addressed with further studies.

Phasing diffuse scattering. Application of the SIR2002 algorithm to the non-crystallographic phase problem

A new phasing algorithm has been used to determine the phases of diffuse elastic X-ray scattering from a non-periodic array of gold balls of 50 nm diameter. Two-dimensional real-space images, showing the charge-density distribution of the balls, have been reconstructed at 50 nm resolution from transmission diffraction patterns recorded at 550 eV energy. The reconstructed image fits well with a scanning-electron-microscope (SEM) image of the same sample. The algorithm, which uses only the density modification portion of the SIR2002 program, is compared with the results obtained via the Gerchberg-Saxton-Fienup HiO algorithm. The new algorithm requires no knowledge of the object's boundary and proceeds from low to high resolution. In this way, the relationship between density modification in crystallography and the HiO algorithm used in signal and image processing is elucidated.

Application of a modified Oszlányi and Sütoab initiocharge-flipping algorithm to experimental data

The structures of two crystals have been solved using a new iterative phasing method. The iterative phasing algorithm is developed from the 'charge-flipping' method proposed by Oszlányi & Süto [Acta Cryst. (2004), A60, 134-141]. Positivity and point-atom constraints are incorporated within this extremely simple and effective algorithm by flipping (sign reversal) of less-positive density values during the iterations. Convergence is reliably achieved and the two structures were solved. This structure solution method does not require information on atomic scattering factors or symmetry. Heavy atoms can be distinguished from light ones by their charge-density values.

Structural study of new hydrocarbon nano-crystals by energy-filtered electron diffraction

A new brittle hydrocarbon has been successfully synthesized in polycrystalline form, and its crystal structure solved by quantitative electron diffraction. By 3D tilting of the nano-crystals, the lattice type and unit cell parameters were determined. (Triclinic, [Formula: see text] A, [Formula: see text] A, [Formula: see text] A, [Formula: see text] degrees, [Formula: see text] degrees, and [Formula: see text] degrees.) Spot diffraction patterns were obtained at -165 degrees C using the Koehler selected-area mode on a LEO 912 TEM fitted with an omega in-column elastic energy filter. The direct methods algorithm was then applied to merged intensities and a trial structure obtained assuming single scattering. This was further refined to obtain good agreement with a small residual of about 10% using multiple scattering calculations. A diagram of the proposed structure is given.

Phase extension in crystallography using the iterative Fienup–Gerchberg–Saxton algorithm and Hilbert transforms

A procedure for phase extension in electron crystallography is proposed based on the iterative Fienup-Gerchberg-Saxton algorithm in combination with the use of discrete Hilbert transforms. This transform is used to provide oversampling in reciprocal space, thus satisfying the Shannon sampling requirement and introducing reflections with fractional indices. When the procedure is combined with the knowledge of a small set of strong phased Bragg reflections from electron-microscope images (or direct methods), the magnitudes of many non-Bragg reflections can be calculated with useful accuracy, thus enhancing the performance of the iterative algorithm for phase extension. The effects of various constraints used in the iterative algorithm are discussed. In this way, it is shown that the iterative algorithm conventionally used for phasing diffuse scattering from non-periodic objects can also be applied to problems in conventional crystallography to find the phases of high-order (resolution) beams from a known set of low-order (resolution) phases.

Structure and bonding in alpha-copper phthalocyanine by electron diffraction

Energy-filtered quantitative electron diffraction at liquid nitrogen temperature has been used to examine the atomic structure and bonding of metastable alpha-Cu phthalocyanine crystals. Three theoretical methods (kinematic, kinematic with excitation errors and Bloch wave) were employed for the intensity calculations. The Bloch-wave method was found to account for dynamical effects by greatly reducing the residual factor between experimental and simulated results. A new method for calculating electron scattering factors for partially charged ions is proposed and the sensitivity of electron diffraction to charge transfer is discussed. The atomic charge states were analyzed for alpha-Cu phthalocyanine using a charge cloud model in which the Gaussian bond charge is positioned along the bonds. Spot patterns were collected in the Kohler mode at two beam energies to reduce error. Using the best-fitting model, a deformation charge-density map is produced and compared to the neutral-atom model. From this, the main features of atomic charge transfer in the alpha-Cu phthalocyanine structure can be seen in the (010) plane.

Solving non-periodic structures using direct methods: phasing diffuse scattering

The problem of reconstructing the charge density of a non-periodic sample from its diffuse X-ray scattering is considered. For a sample known to be isolated, an artificial superlattice may be assumed and the numerical direct methods of crystallography applied to the continuous distribution of diffuse scattering in order to solve the phase problem. This method is applied to simulated soft-X-ray transmission speckle patterns from a two-dimensional array of gold balls of 50 nm diameter. The results are relevant to efforts to phase the scattering from many individual macromolecules that cannot be crystallized, and to the scattering from individual inorganic nanoparticles.

Frequent recovery of a single clonal type of multidrug-resistant Staphylococcus aureus from patients in two hospitals in Taiwan and China

One hundred thirty-two methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from patients with S. aureus infections between January 1998 and February 1999 in two hospitals, one located in Taipei, Taiwan, and another in Nanjing, People's Republic of China, were examined for antibiotic susceptibility and for clonal type by a combination of three methods: hybridization of ClaI restriction digests with mecA- and Tn554-specific DNA probes and pulsed-field gel electrophoresis of chromosomal SmaI digests. Selected isolates representing each clonal type were also analyzed by spaA typing, multilocus sequence typing, and a multiplex PCR method capable of identifying the structural type of the staphylococcal cassette chromosome mec (SCCmec) carried by the bacteria. The overwhelming majority of isolates (126 of 132 or 95%) belonged to minor variants of a single clonal type resembling the Brazilian and Hungarian epidemic MRSA clones, which showed a common spaA type and which were either sequence type 239 (ST239) or ST241 (a single-locus variant of ST239) in association with SCCmec type III or IIIA.

Kinematic and dynamical CBED for solving thin organic films at low temperature; experimental tests with anthracene

Low-dose, low-temperature kinematic and dynamical convergent-beam electron diffraction (CBED) patterns from thin organic crystalline films have been used for the measurement of structure-factor amplitudes and phases. Kinematic conditions are identified by the observation of uniform intensity within the CBED discs and used to determine structure-factor magnitudes. CBED patterns from thicker regions affected by multiple scattering give structure-factor signs, which are varied for best fit. The use of a small probe (and the Kohler SAD mode) minimizes bending artifacts. A new method of thickness determination is evaluated. The approach is tested using experimental data from the centrosymmetric anthracene structure, the results compared with direct methods, and a potential map derived from experimental data. The faint peaks due to H-atom positions may be distinguished. Key issues influencing the validity of the method such as the appropriate dimension of the structure-factor matrix, sample thickness and crystal orientation are discussed.

Comparison of laparoscopic choledochotomy closure techniques

BACKGROUND

Laparoscopic common bile duct exploration (CBDE) has traditionally been accompanied by T-tube drainage. However, other methods of choledochotomy closures have been reported. This study compared three laparoscopic methods of choledochotomy closure in a prospective, randomized fashion to determine which method should be the preferred technique.

METHODS

In this porcine model, 24 animals initially underwent laparoscopic common bile duct (CBD) clipping to simulate an obstruction. Two days later, the animals underwent laparoscopic clip removal and simulated CBDE through a 1.5-cm choledochotomy. The animals were then randomized to one of three groups: primary choledochotomy closure (group I), antegrade CBD stenting with primary closure (group II), or T-tube placement (group III). To assess for CBD stenoses and leaks, the animals were killed 2 months postoperatively, at which time a cholangiogram was performed and the bile duct harvested. The ratio of proximal CBD to choledochotomy site was assessed radiographically and histologically.

RESULTS

The operative time was significantly longer in group III (200 +/- 13 min, p < 0.05) than in group I (141 +/- 17 min) and group II (154 +/- 16 min). The ratio of the proximal CBD diameter to the choledochotomy site diameter by cholangiogram was 2.1:1.0 in group I, to 1.2:1.0 in group II, and 1.1:1.0 in group III (p < 0.01). The ratio of the proximal CBD intraluminal area to the choledochotomy site intraluminal area was 2.1:1.0 in group I compared to 1.1:1.0 in groups II and III (p < 0.01). None of the animals developed jaundice or sepsis.

CONCLUSION

Significant stenoses were present at the choledochotomy site in the primary closure group, and T-tube placement resulted in prolonged operative times. We conclude that laparoscopic antegrade CBD stenting with primary closure of the choledochotomy site is the preferred technique after choledochotomy in an animal model. Further assessment in a clinical trial is warranted.

Existence of homologous sequences corresponding to cDNA of the ver gene in diverse higher plant species

The presence of DNA homologues corresponding to verc203 (vernalization-related cDNA clone) was investigated by molecular hybridization techniques. The genes were detected in 16 plant species that cover 12 subclasses of the Takhtajan system of angiosperms classification including diverse model species. The results of Southern blot analysis showed a low copy number of this gene existed in rice, wheat, barley and Arabidopsis. The hybridization result of PCR products demonstrated the conservation of the gene corresponding to ver203 in diverse plants. The phylogenetic tree of the ver203 gene in tested plants was supported by evolution relationship of species. The ver203 gene expressed in a vernalized plumule winter wheat, instead of the root. And the endosperm before the treatment was essential for the ver203 expression during vernalization in wheat. In Arabidopsis thaliana, the pattern of expression showed that the gene corresponding to ver203 was expressed at low temperature for 14 days. Gibberellin (GA3) may accelerate the expression of ver203 gene in Arabidopsis exposed to low temperature. However, it could not replace vernalization treatment to initiate the gene expression.

Sex differences of body fat distribution and cardiovascular dysmetabolic factors in old age

BACKGROUND

The relationship between sexual differences of body fat distribution and cardiovascular dysmetabolic factors in old people is controversial.

OBJECTIVES

To use centrality index-derived body fat distribution to clarify its relationship with glucose tolerance status, blood pressure and lipid profile.

DESIGN

Cross-sectional survey in a tertiary-care medical centre in Tainan, Taiwan.

SUBJECTS

114 men and 101 women, aged > or = 60 years.

METHODS

We measured total % body fat and body fat distribution (reflected as centrality index) by dual energy x-ray absorptiometry, and plasma glucose, glycosylated haemoglobin, blood pressure, total cholesterol, triglyceride, high-density lipoprotein (HDL) cholesterol and atherogenic index (total cholesterol/HDL cholesterol).

RESULTS

Centrality index showed better linear correlation with cardiovascular dysmetabolic factors than body mass index, total % body fat and waist-to-hip ratio, except in systolic blood pressure. Women had higher total % body fat, but the % abdominal fat and centrality index were both higher in men. Subjects with diabetes mellitus had the highest centrality index compared with those with impaired or normal glucose tolerance. After adjustment for age and total % body fat, men still had higher diastolic blood pressure, triglyceride levels and atherogenic indices, but lower HDL cholesterol levels than women. However, when further adjusted for centrality index, the sex differences in cardiovascular dysmetabolic factors were statistically insignificant.

CONCLUSIONS

Centrality index is a useful method for assessing body fat distribution in older people. Body fat distribution is an important factor in sex differences of cardiovascular dysmetabolic factors in old people.

Mechanical and histological evaluations of hydroxyapatite-coated and noncoated Ti6Al4V implants in tibia bone

This paper evaluates the behavior of hydroxyapatite (HAP) coated and noncoated Ti6Al4V implants in dog tibia after 3 and 5 months implantation. HPA-coated implants were obtained by plasma spraying. XRD, SEM, and EPMA were employed to estimate the coating characteristics and their behavior in vivo. Investigation of material characteristics showed that the as-received coatings consisted mainly of amorphism and HAP phase. Other phases such as TCP and CaO were identified due to thermal changes of HAP particles in plasma flame. SEM micrographs showed a typical microstructure of plasma-sprayed coating. The as-received coating was formed by well-melted pancake-like splats that lead to a dense coating with a rough surface. Lamellar structure, micropores, and microcracks, observed inside the coating, are characteristic of plasma spraying. Push-out tests revealed that HAP coating had a significant promotion of interfacial shear strength. The shear strength between bone and HAP-coated implants was much higher than that between bone and noncoated implants due to the different bone-implant interfaces formed after implantation. SEM observation revealed a direct attachment between HAP coating and newly formed bone. However, noncoated implants were separated from newly formed bone by fibrous tissues. Ti ions were found to be released into the surrounding environment after long time immersion in body fluid, and thus caused low shear strength. Prolongation of implantation time had different effects on shear strength. It improved the shear strength between HAP-coated implant and newly formed bone. However, it had little effect on that between noncoated implant and surrounding tissues.

Surgical treatment of hemorrhoids: prospective, randomized trial comparing closed excisional hemorrhoidectomy and the Harmonic Scalpel technique of excisional hemorrhoidectomy

PURPOSE

The object of this study was to evaluate technique using the ultrasonically activated scalpel as an alternative to closed hemorrhoidectomy in an unbiased evaluation of this new technology.

METHODS

Thirty patients with Grade 2 or 3 symptomatic hemorrhoids were prospectively randomized to undergo closed hemorrhoidectomy assisted by electrocautery or hemorrhoidectomy with the ultrasonically activated scalpel, i.e., the Harmonic Scalpel. We evaluated the difference between techniques in operative time, postoperative pain, incontinence, and quality of life (using the Short Form-36 survey), as well as complications.

RESULTS

Mean operative time for closed hemorrhoidectomy with electrocautery was 35.7 +/- 3 minutes; for Harmonic Scalpel patients, it was 31.7 +/- 2 minutes (P < 0.37). There was no statistical difference in operative time for two- or three-column hemorrhoidectomy. There was no significant difference in pain measurements reported on Day 1 (5.8 +/- 0.4 for electrocautery and 5.6 +/- 0.6 for Harmonic Scalpel, P < 0.82). On postoperative Day 7, the difference in pain between groups approached significance, with pain reported as 3.7 +/- 0.3 for electrocautery and 5.1 +/- 0.7 for Harmonic Scalpel(R) (P < 0.06). At six weeks, both groups were pain free. There was a significant decrease in pain between postoperative Days 1 and 7 in the electrocautery patients that was not seen in the Harmonic Scalpel patients. Incontinence measured preoperatively, at postoperative Day 7, and at postoperative Week 6 was similar for both groups and reflected occasional incontinence of gas. When the various items of the Short Form-36 survey were compared, there was no significant difference between posttreatment and preoperative values. There was no difference in the number of complications between patient groups.

CONCLUSION

Although the Harmonic Scalpel is an effective tool in the treatment of hemorrhoidal disease, we found no specific advantage in postoperative pain, fecal incontinence, operative time, quality of life, or complications compared with traditional closed hemorrhoidectomy.

Correlation between serum lipid concentrations and psychological distress

This study examines the correlations between serum lipid levels and psychological distress. There were 4444 consecutive attendees of general health clinics who participated in the study. Psychological symptoms were measured by the Taiwanese version of the Symptoms Check List 90, revised (T-SCL-90-R). Levels of fasting serum lipids, including total cholesterol, total triglycerides and high-density lipoprotein cholesterol (HDL-C), were determined. Multiple linear regression analyses, with adjustment for confounders, revealed that the concentration of HDL-C had significant inverse associations with scores of depression, somatization and phobic anxiety. Women with an HDL-C level lower than 35 mg/dl scored significantly higher on depression, interpersonal sensitivity, phobia, anxiety, somatization and aggressive hostility, while subjects with a total cholesterol concentration lower than 160 mg/dl scored significantly higher on anxiety, aggressive hostility, phobia, and psychoticism. This study provides, for the first time, comprehensive data derived from the Taiwanese population on the link between lipids and psychological symptoms, revealing a reverse correlation between depression and serum concentrations of HDL-C.

X-ray absorption spectroscopy investigations on oxidized Ni/Au contacts to p-GaN

X-ray absorption spectroscopy was used to investigate the electronic structure of as-deposited and oxidized Ni/Au contacts to p-GaN and to elucidate the mechanism responsible for low impedance. X-ray absorption near edge spectra of Ni K- and L3,2-edges clearly indicate formation of NiO on the sample surface after annealing. The reason for low impedance may be attributed to increase in hole concentration and existence of p-NiO layer on the surface.

[Role of substance P in pressor response of nucleus ventromedialis to glutamate]

AIM

To analyze mechanism underlying pressor response of the nucleus ventromedialis (NVM) to glutamate.

METHODS

Effects of different drugs delivered by intra-brain or i.v. injections on blood pressure and heart rate were observed in rats.

RESULTS

(1) Excitation of the NVM by L-glutamate (Glu), injection of substance P (SP) into the nucleus dorsomedialis (NDM), nucleus paraventricularis (NPV) or rostral ventrolateral medulla (RVL), all induced pressor responses. (2) NVM pressor responses could be attenuated by preinjection of [D-Pro2, D-Phe7, D-Trp9]-SP (DPDPDT, a substance P antagonist) bilaterally into the NDM, NPV or RVL, but preinjection of atropine into the RVL had no such effect. (3) Phentolamine (i.v. ) also reduced the NVM pressor response, but propranolol or methyl atropine (i.v.) had no significant effect.

CONCLUSION

The NVM SPergic neurons can activate NDM SPergic neurons, which proceed to excite the NPV pressor area (SP receptor) and RVL (SP receptor)-sympathetic vasoconstrictor nerve system, thereby induce pressor response. The cardiac sympathetic and cardiac vagal nerves are not involved in this response.

A statistical design to evaluate the influence of manufacturing factors on the material properties and functionalities of microcrystalline cellulose

The aim of this study is to statistically evaluate the effects of manufacturing factors on the material properties and functionalities of microcrystalline cellulose (MCC) products. How the material properties of MCC products dominate their functionalities was further explored. Results demonstrate that the desired material properties and functionalities of MCC products can be obtained by manipulation of the manufacturing factors using proper polynomial equations, and the key manufacturing factor is temperature. On the other hand, the functionalities can be quantitatively predicted by material properties. Meanwhile, the key material property is molecular mass in controlling MCC functionalities. The particle morphologies may also serve as important material properties. In conclusion, the careful control of temperature during the manufacture of MCC might minimize inter-batch variation. The correlation of the material properties of MCC products with their functionalities might help the formulation designer rationally select proper MCC products. The universal harmonization of MCC products might be achieved by the regulation of their molecular mass, surface roughness, and roundness.

Methanotrophic production of extracellular polysaccharide in landfill cover soils

A bench-scale soil reactor was used to study methane oxidation and EPS production under tropical conditions. The study of pertinent environmental factors affecting EPS production was carried out by batch cultivation of methanotrophs. These factors included variations in temperature (20 degrees C to 45 degrees C), soil water content (5% to 33%), and the supply ratios of methane/oxygen. The bench-scale study revealed that excessive EPS was accumulating in an active methane oxidation zone located 5-45 cm below the soil surface of the reactor. The observed peak rates of oxidation could not be sustained over an extended period of time due to EPS accumulation. Results from the batch cultivation experiments confirmed the production of EPS in soils subject to methane oxidation. EPS production was found to correlate with methane oxidation rates which, in turn, were regulated by the variance of temperature and soil water content. A larger amount of EPS production was obtained at 30 degrees C and 17% soil water content. Oxygen is required for methane oxidation; however, at high oxygen tension it may accelerate the production of EPS by methanotrophs causing limited oxygen diffusion and declining rates of methane oxidation.

Relationships of age, menopause and central obesity on cardiovascular disease risk factors in Chinese women

OBJECTIVE

To evaluate the inter-relationships of age- and menopause- related changes of general obesity and body fat distribution and their independent effects on cardiovascular risk factors.

DESIGN

Cross-sectional study.

SUBJECTS

One-hundred and thirty-six premenopausal and 193 postmenopausal Chinese women with body mass index (BMI) < 30 kg/m2.

MEASUREMENTS

Anthropometric surrogates of general obesity (BMI, total body fat percentage) and central obesity (waist-to-hip ratio, centrality index) were measured. Blood pressure, 75 g oral glucose tolerance test, glycosylated hemoglobin A1c and lipid profiles were also measured.

RESULTS

Significant correlation coefficients between age, general obesity, central obesity and cardiovascular disease risk factors were noted. Through the menopausal transition, the BMI and total body fat percentage were increased significantly. After adjustments for age and BMI, the postmenopausal women showed higher android fat percentage, centrality index, glycosylated hemoglobin A1c, serum concentrations of total cholesterol, low-density lipoprotein (LDL) cholesterol and atherogenic indices than the premenopausal women. In multiple stepwise regression models, age exerted independent effects on oral glucose tolerance test 2 h plasma glucose level, systolic and diastolic blood pressure, total cholesterol level, and LDL cholesterol. Menopause was an independent variable in relation to the changes of glycosylated hemoglobin A1c, total and LDL cholesterol levels, triglyceride levels and atherogenic indices. The centrality index was the major independent variable of all the cardiovascular disease risk factors, except total and LDL cholesterol level. However, the variation of total body fat percentage had no independent effect on any cardiovascular disease risk factors.

CONCLUSION

Through the aging and menopausal effects, women will increase total body fat content, favoring the central body fat distribution. Age, menopause and central obesity were all independent and significant factors to the cardiovascular disease risk factors in Chinese women.

Epidemiologic study of type 2 diabetes in Taiwan

Diabetes mellitus (DM) in adults is a global health problem, although its prevalence varies widely between different populations and the rate has generally increased worldwide. In Taiwan, the mortality rate from DM has almost doubled over the past 10 years. The prevalence of DM in Taiwan was established between 1985 and 1996 and the rates were between 4.9 and 9.2%. The prevalence of impaired glucose tolerance (IGT) was 15.5% (men 15% and women 15.9%). The prevalence of DM and IGT increased significantly with age for both genders. The significant factors associated with newly diagnosed DM were age, BMI, family history of DM, systolic blood pressure (hypertension), physical activity and serum triglyceride levels. The prevalence of large vessel disease (LVD) in DM and non-diabetic subjects were 20.0 and 12.9%, respectively. Among diabetics, 15.8% had ischemic heart disease (IHD), 1.7% leg vessel disease (leg VD), and 2.5% stroke. In non-diabetics, the prevalence of the aforementioned macroangiopathies were 11.5, 0.2 and 1.2%, respectively. The diabetics had a significantly higher prevalence of macrovascular disease than non-diabetic subjects. The most significantly associated with the LVD was serum cholesterol levels. Serum cholesterol and HbA1(c) were significantly associated with the development of IHD. Cigarette smoking and female gender were significantly associated with the leg VD. The prevalence of diabetic retinopathy (DR) was 35.0%. (background DR 30%, preproliferative DR 2.8% and proliferative DR 2.2%, respectively.) The prevalence of DR for previously and newly diagnosed diabetics were 45.2 and 28.3% (men 42.8 vs. 33.3% and women 47.5 vs. 24.8%), respectively. From multiple logistic regression analysis, duration of DM was the most important risk factor related to DR. Diabetic subjects treated with insulin had a higher risk of developing retinopathy than those treated with dietary control. The prevalence of nephropathy and neuropathy were 12.9 and 23.5%, respectively. For those patients with and those without nephropathy and neuropathy, the duration of DM, percentage of insulin treatment, percentage of hypertension, and fasting plasma glucose were significantly different. Diabetic duration, hypertension, insulin treatment and glycemic control consistently correlated with nephropathy and neuropathy. In conclusion, the prevalence of DM in Taiwan was between 4.9 and 9.2%, and the prevalence of IGT was 15.5%. The possible risk factors of newly diagnosed diabetes were age, family history of DM, BMI, SBP (hypertension), physical activity and triglyceride levels. Diabetes in Chinese subjects share many characteristics similar to other Asian populations. The burden imposed by the chronic complications of diabetes is massive. In Taiwan, the mortality rates from DM have increased greatly over the past 10 years. Reduction of the modificable risk factors such as BMI, hypertenion and dyslipidemia, and increase of physical activity and good glycemic control through public health efforts may help to reduce the risk of DM and its chronic complications.

Nasopharyngeal carcinoma: the role of the dentist in assessment, early diagnosis and care before and after cancer therapy

Nasopharyngeal carcinoma (NPC) may present first to the dental profession as facial pain, neck masses, difficulty in speech and swallowing, ear, nose and throat symptoms, or as symptoms of temporomandibular disorders (TMD). Recognition of the signs and symptoms are essential in order to lead to the correct diagnosis, and to avoid inappropriate intervention that may further delay diagnosis and initiation of treatment of the cancer. Differentiation between NPC and TMD may be facilitated by specific questioning of other symptoms that are not frequently associated with TMD such as neck masses, nasal obstruction, recent unilateral hearing deficit and epistaxis. The general dentist can become involved at three stages of a patient's experience with NPC: Stage 1, recognition of signs and symptoms; Stage 2, pre-treatment dental assessment; and Stage 3, post-treatment support. This paper is intended to: (1) alert the general dentist of the signs and symptoms associated with NPC, such that timely and appropriate treatment may ensue; (2) provide a basic outline for assessment, preparation, palliation and continuing care of a patient diagnosed with NPC; and (3) underline the significant role of the general dentist in achieving an optimal quality of life for these patients

Development of a laparoscopic approach to neurolytic celiac plexus block in a porcine model

BACKGROUND

Neurolytic celiac plexus block (NCPB) is an effective method of palliative pain control in cases of inoperable pancreatic cancer. This study was undertaken to evaluate the feasibility of a laparoscopic approach to NCPB in an experimental animal model.

METHODS

The laparoscopic technique for NCPB was developed in an acute study of six domestic swine followed by a chronic study of nine domestic swine that were monitored 3-21 days after surgery for adverse neurologic, gastrointestinal, or other sequelae. Using a four-port laparoscopic technique, the esophageal hiatus was dissected to expose the aorta at the level of the diaphragmatic crura. Under combined endoscopic and laparoscopic ultrasound (LUS) guidance, 5 ml of sclerosant dye (95% ethanol mixed with India ink) was injected into either side of the para-aortic soft tissue via a percutaneously placed 18-gauge spinal needle. After the animals were killed, the aorta and periaortic tissue were harvested from each animal for gross and histologic analysis.

RESULTS

Under LUS guidance, sclerosant was injected successfully into the para-aortic soft tissue in all animals. There were no intraoperative complications in the acute animal group. Placement of sclerosant injection was successful in all nine chronic cases. Two pigs in the chronic study group died in the immediate postoperative period secondary to pneumothorax. No adverse neurologic, gastrointestinal, or other sequelae were observed in the remaining seven animals at 3-21 days postoperatively. After the animals were killed, we found no injuries to the aorta or esophagus, and histologic analysis demonstrated good placement of dye-labeled sclerosant with no compromise of aortic structural integrity.

CONCLUSION

A laparoscopic approach to the aortic hiatus and NCPB is feasible. Further studies are warranted to evaluate this approach in patients who undergo staging laparoscopy for pancreatic cancer and are found to have unresectable disease.

Consumer health information websites in Taiwan

Developers of consumer health information (CHI) websites and pages in Taiwan have included: 1) individuals; 2) general hospitals; 3) disease-oriented associations; 4) government health administrative agencies; and 5) commercial corporations. General hospitals have developed the largest number of sites, but the quality of these sites differs widely. The unprecedented impact of health-oriented websites on medical care and the health of the public in general necessitates the establishment of credible instruments for the evaluation and rating of the quality of such websites and pages. In this paper, we describe the current status of CHI websites and pages in Taiwan. Suggestions for improving the content of CHI websites and pages are also proposed.

Hypertension in elderly persons: its prevalence and associated cardiovascular risk factors in Tainan City, southern Taiwan

BACKGROUND

Hypertension was the eighth leading cause of death in Taiwan in 1996, and the prevalence of hypertension has increased recently. The purpose of the study was to assess the prevalence of hypertension and its associated cardiovascular risk factors in elderly persons in Tainan City, southern Taiwan.

METHODS

The study was a cross-sectional, population-based study. We used the stratified cluster sampling method to enroll subjects aged 65 years and above, 1435 persons in total, into our study. Questionnaire interview, body weight, body height, and blood pressure measurement were completed for 876 participants (response rate of 70.2%) at each subject's home by home visit.

RESULTS

Hypertension was defined according to the criteria of the Fifth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. The crude prevalence of hypertension was 60.4% (men 59.1%, women 61.9%); previously diagnosed hypertension was 31.1% (men 29.4%, women 33.1%); and newly diagnosed hypertension was 29.3% (men 29.7%, women 28.8%). The hypertensive group had a higher body mass index (BMI) than the normotensive group. There were no lifestyle differences such as smoking, drinking, eating a vegetarian diet, reading health information, and undergoing a health examination in the past year between the hypertensive and normotensive groups. However, the hypertensive group had a higher prevalence of regular exercise than did the normal blood pressure group on univariate analysis. Only BMI and family history of hypertension had a significantly positive association with hypertension on multiple logistic regression analysis.

CONCLUSIONS

The crude prevalence of hypertension was 60.4% in elderly persons in Tainan City. Subjects who had family history of hypertension and higher BMI had a higher risk of hypertension, so they should be screened for high blood pressure regularly.

Linkage of a gene for familial hypobetalipoproteinemia to chromosome 3p21.1-22

Familial hypobetalipoproteinemia (FHBL) is an apparently autosomal dominant disorder of lipid metabolism characterized by less than fifth percentile age- and sex-specific levels of apolipoprotein beta (apobeta) and low-density lipoprotein-cholesterol. In a minority of cases, FHBL is due to truncation-producing mutations in the apobeta gene on chromosome 2p23-24. Previously, we reported on a four-generation FHBL kindred in which we had ruled out linkage of the trait to the apobeta gene. To locate other loci containing genes for low apobeta levels in the kindred, a genomewide search was conducted. Regions on 3p21.1-22 with two-point LOD scores >1.5 were identified. Additional markers were typed in the region of these signals. Two-point LOD scores in the region of D3S2407 increased to 3.35 at O = 0. GENEHUNTER confirmed this finding with an nonparametric multipoint LOD score of 7.5 (P=.0004). Additional model-free analyses were conducted with the square root of the apobeta level as the phenotype. Results from the Loki and SOLAR programs further confirmed linkage of FHBL to 3p21.1-22. Weaker linkage to a region near D19S916 was also indicated by Loki and SOLAR. Thus, a heretofore unidentified genetic susceptibility locus for FHBL may reside on chromosome 3.

Cardiac and pulmonary vagal neurons receive excitatory chemoreceptor input

The effects of hypercapnia and hypocapnia on the activities of the cardiac and pulmonary vagal single fibers were examined in the decerebrated, unanesthetized, paralyzed, and vagotomized cats. The animals breathed 100% O2. Fractional end tidal CO2 concentration was raised to 9% by adding CO2 into the O2 inlet. Average discharge rate of efferent cardiac vagal units (n=10) increased from 1.0+/-0.3 to 2.2+/-0.3 Hz. Hypocapnia apnea was produced by hyperventilation. Activities of cardiac vagal units tested (n = 4) showed dramatic decrease (0.1+/-0.0 Hz). Mean arterial blood pressure did not change significantly under these conditions. In contrast, only instantaneous firing rate during inspiration was significantly increased for efferent pulmonary vagal units (n = 11) during hypercapnia. The activities of the 3 pulmonary vagal units tested with hypocapnia decreased significantly. We concluded that cardiac and pulmonary vagal neurons were excited by chemoreceptor input.

Chlamydia pneumoniae infection in community-acquired pneumonia in Taiwan

Chlamydia pneumoniae is a common cause of pneumonia worldwide. This study examined the role of C. pneumoniae in 229 patients with community-acquired pneumonia. The ages of the patients ranged from 2 to 95 years. Sera were assayed for IgM and IgG antibodies with microimmunofluorescence (MIF). An IgM titer equal to or greater than 1:20 and IgG titer equal to or greater than 1:64 were considered positive. The prevalence of positive IgG among all of the patients was 75.1% (172/229). The seroprevalence was 81.8% (9/11) for patients in the 11- to 20-year-old group, 63.6% (14/22) in the 31- to 40-year-old group and 88.1% (52/59) in the 71- to 80-year-old group. All patients had a negative result for IgM antibody. Twenty-five of the patients had an IgG titer equal to or greater than 1:512, indicating the presence of current infection or reinfection. Age older than 60 years (vs. < or = 60 years) was a risk factor for C. pneumoniae seropositivity in patients with community-acquired pneumonia (p < 0.001). Males had a significantly higher seroprevalence of C. pneumoniae infection (p = 0.1010). Patients older than 60 years were more likely to have C. pneumoniae infection (p = 0.1107). In this series, C. pneumoniae infection accounted for 10.9% (25/229) of community-acquired pneumonia. The most common clinical manifestations included fever (92%), productive cough (52%), white blood cell more than 10,000/mm3 (56%), and bilateral pulmonary infiltrate (60%).

Community-acquired methicillin-resistant Staphylococcus aureus endocarditis with septic embolism of popliteal artery: a case report

A 20-year-old man presented with a 14-day course of fever. Physical examination showed petechiae of the conjunctivae, Janeway lesions on both hands, a grade III/VI systolic murmur over the apex, pulseless dorsal pedal artery and posterior tibial artery of the right leg, and a pale right foot. Femoral arteriogram of the right leg revealed total occlusion of the popliteal artery with collateral circulation of the posterior tibial artery. Transthoracic echocardiogram showed trace mitral regurgitation. Embolectomy of the right popliteal artery was done, and penicillin and gentamicin treatment was administered. However, postoperative fever developed intermittently. Transesophageal echocardiogram disclosed vegetation over the anterior leaflet of the mitral valve. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from all three cultures of blood drawn at admission and from the septic embolus during operation. He had neither evidence of underlying heart disease, nor history of intravenous drug abuse or hospitalization. Exploratory cardiotomy with removal of vegetation on the mitral valve was performed followed by a 4-week treatment with intravenous vancomycin. After discharge, he was well at 2-year follow-up.

Epimeric separation of L-ascorbic acid and D-isoascorbic acid by capillary zone electrophoresis

Capillary zone electrophoresis (CZE) was used for separation of L-ascorbic acid (L-AA) and D-isoascorbic acid (D-IAA) in a model system. The effects of borate buffer concentration (0.05-0.25 M) and pH (pH 7.5-9.0) on migration time, resolution (Rs), and theoretical plates (N) were investigated. The migration times of L-AA and D-IAA increased with the increasing pH of carrier electrolyte (0.2 borate buffer), and the resolutions (Rs) of L-AA and D-IAA were calculated to be 12.98 at pH 9.0. Concentrations of borate buffer (pH 9.0) increased the Rs values of L-AA and D-IAA, and buffer concentrations >0.1 M were found to be effective for separation of L-AA and D-IAA. Methanol in the carrier electrolyte was also influential in improving the separation of L-AA and D-IAA, which increased with the increasing concentrations (0-10%) of methanol. The optimal separation conditions for L-AA and D-IAA were as follows: carrier electrolyte, 0.2 M borate buffer (pH 9.0); applied voltage, 25 kV, with an uncoated fused silica capillary, 75 microm (i.d.) x 57 cm.

The mitotic centromeric protein MEI-S332 and its role in sister-chromatid cohesion

Faithful segregation of sister chromatids during cell division requires properly regulated cohesion between the sister centromeres. The sister chromatids are attached along their lengths, but particularly tightly in the centromeric regions. Therefore specific cohesion proteins may be needed at the centromere. Here we show that Drosophila MEI-S332 protein localizes to mitotic metaphase centromeres. Both overexpression and mutation of MEI-S332 increase the number of apoptotic cells. In mei-S332 mutants the ratio of metaphase to anaphase figures is lower than wild type, but it is higher if MEI-S332 is overexpressed. In chromosomal squashes centromeric attachments appear weaker in mei-S332 mutants than wild type and tighter when MEI-S332 is overexpressed. These results are consistent with MEI-S332 contributing to centromeric sister-chromatid cohesion in a dose-dependent manner. MEI-S332 is the first member identified of a predicted class of centromeric proteins that maintain centromeric cohesion.

Discriminating glucose tolerance status by regions of interest of dual-energy X-ray absorptiometry. Clinical implications of body fat distribution

OBJECTIVE

To determine whether measuring body fat distribution by dual-energy X-ray absorptiometry (DEXA) can be used to discriminate glucose tolerance status.

RESEARCH DESIGN AND METHODS

Using a 75-g oral glucose tolerance test, a total of 1,015 Chinese subjects (559 men and 456 women) were categorized as having normal glucose tolerance (NGT), impaired glucose tolerance (IGT), or diabetes. Blood pressure and lipid profiles of these subjects were measured. Waist-to-hip ratio (WHR) and DEXA were used to evaluate the varying patterns of body fat distribution among the groups.

RESULTS

Body fat distribution, as reflected by WHR and the centrality index, showed significant partial correlation coefficients with glycosylated hemoglobin, blood pressure, and lipid profiles in all subjects. After adjusting for age and BMI, there were significant differences among the three glycemic groups for all the cardiovascular risk factors except for total cholesterol level. The diabetic group had a significantly higher WHR and centrality index, but lower femoral fat percentage than the NGT and IGT groups. The diabetic group also showed higher abdominal fat percentage than the NGT group. Moreover, the IGT group had a higher centrality index than the NGT group. However, no significant differences were found in the percentage of lean tissue mass among the three groups. Using multiple stepwise logistic regression models, the centrality index remained a significant factor for discriminating different glucose tolerance status independent of the percentage total body fat.

CONCLUSIONS

Central obesity has shown significant correlation with cardiovascular risk factors among the three different glycemic groups. Centrality index measured by DEXA appears to be the better predictor of glucose intolerance, compared with WHR, abdominal fat, and general obesity (reflected by percentage total body fat or BMI) in a large cohort of the Chinese population.

Corticotropin releasing factor and substance P mediate the nucleus amygdaloideus centralis-nucleus ventromedialis-nucleus dorsomedialis pressor system

Prolonged emotional stress is an important factor in the development of neurogenic hypertension, but its mechanism is still unclear. The purpose of the present study is to analyze the possible neural basis of hypertension induced by prolonged emotional stress. In the brain many nuclei are involved in emotional reaction, stress or defense response; among them the nucleus amygdaloideus centralis (AC) is the most important one which widely connects with other nuclei controlling emotion and stress, such as nucleus ventromedialis (NVM), nucleus dorsomedialis (NDM), nucleus paraventricularis (NPV) etc. These nuclei contain corticotropin releasing factor (CRF)- and substance P (SP)-immunoreactive cell bodies, nerve terminals and corresponding receptors. Our previous and present studies showed that microinjection of CRF or SP into these nuclei induced pressor responses. These data imply that excitation of the AC can activate many nuclei controlling emotion and stress via CRF and SP, and excessive activities of these nuclei may be the neural basis of hypertension induced by prolonged emotional stress. The present study revealed that (1) the AC pressor response to glutamate (Glu) could be reduced by preinjection of CRF antagonist (alpha-Helical CRF[9-41] or SP antagonist ([D-Pro(2), D-Phe(7), D-Trp(9)]-substance P) into bilateral NVM, (2) the NVM pressor response to Glu were decreased by pretreatment of the NDM with CRF- or SP-antagonist, (3) the AC-, NVM- or NDM-pressor responses were all attenuated by preinjection of CRF- or SP-antagonist into bilateral NPV or rostral ventrolateral medulla (RVL). The results indicate that excitation of the AC can indirectly activate the NPV and RVL to evoke pressor response via the NVM-NDM, CRF and SP are transmitters in each connection of this pathway; this is one component of the mechanism underlying the AC pressor response. Taken together with the findings of our previous studies, it provides neurophysiological basis for the above-mentioned implications.

Postural hypotension and postural dizziness in patients with non-insulin-dependent diabetes

BACKGROUND

Postural hypotension with a decline of 20 mm Hg or more in systolic blood pressure on standing is considered a potentially dangerous hypotensive response. Postural dizziness is often strongly associated with postural hypotension. However, there is conflicting evidence, and previous studies have been confined to the elderly, not specifically to patients with diabetes. Thus, we evaluated the association between postural hypotension and postural dizziness, and determined the factors most likely related to postural hypotension in patients with diabetes.

METHODS

The subjects were 204 consecutive noninsulin-dependent patients with diabetes and 408 age- and sex-matched control subjects. Postural hypotension was defined as a decline of 20 mm Hg or more in systolic blood pressure 1 minute after standing. Postural dizziness was any feelings of dizziness, lightheadedness, or faintness that occurred while standing during the examination.

RESULTS

The prevalence of postural hypotension and postural dizziness in patients with diabetes was higher than in control subjects. Those patients with both diabetes and postural hypotension were older and had higher supine systolic blood pressures and higher plasma glycosylated hemoglobin and fasting glucose levels. They had higher prevalence of postural dizziness, hypertension, and cerebrovascular disease, and lower standing systolic blood pressures than those without postural hypotension. They also were more often being treated with antihypertensive agents. Only 32.8% of patients with diabetes with postural hypotension suffered from postural dizziness. Postural dizziness, hypertension, cerebrovascular disease, and plasma glycosylated hemoglobin levels were independently associated with postural hypotension in patients with diabetes.

CONCLUSIONS

Postural dizziness, glycemic control, hypertension, and cerebrovascular disease were important determinants of postural hypotension in patients with diabetes. Postural hypotension was associated with postural dizziness, but it cannot be determined clinically just from the presence of postural dizziness because the sensitivity for diagnosis of postural hypotension is low.

Hepatitis B vaccination in high-risk infants: 10-year follow-up

The long-term efficacy of hepatitis B vaccination among high-risk infants was determined in 805 vaccine responders, immunized at birth in Taiwan during 1981-1984 and followed to age 10 years, via life table survival and Cox multivariate analyses. At 10 years, cumulative persistence of antibody to hepatitis B surface antigen (anti-HBs) was 85%, and cumulative incidence of hepatitis B virus (HBV) infection was 15%. Three children became carriers. Twelve-month anti-HBs titer was the strongest predictor of efficacy. The higher the initial titer, the lower the risk of anti-HBs loss (relative risk [RR], 0.26 for titer of 100-999 mIU/mL; RR, 0.08 for titer >1000 mIU/mL; P<.001) and HBV infection (RR, 0.55 and 0.27; P<.05). Maternal hepatitis B e antigen positivity but not hepatitis B immunoglobulin dose or gender predicted greater antibody persistence to age 10 years. Because the level of antibody persistence remained high and few became carriers, booster revaccination within 10 years seems unnecessary.

Sodium hyaluronate carboxymethylcellulose-based bioresorbable membrane (Seprafilm)--does it affect tumor implantation at abdominal wound sites?

PURPOSE

This study examines the effects of a sodium hyaluronate-based bioresorbable membrane (Seprafilm) on tumor implantation at surgical wound and laparoscopic trocar sites.

METHODS

GW-39, an established human colon cancer line carried in immunocompetent golden Syrian hamsters was used as the experimental model. Under general anesthesia, a 2-cm midline incision was made to allow placement of four 5-mm abdominal trocars. Hamsters were then randomly assigned to preSeprafilm, postSeprafilm, and control (no Seprafilm) groups. In the preSeprafilm group 0.5 ml of a 5 percent (vol/vol) suspension of the GW-39 tumor cells (approximately 1.675 x 10(6) cells) was injected into the abdomen of each hamster via midline incision. Trocars were removed, the wounds were closed, and 1 cm2 of Seprafilm was placed on the peritoneal surface of each trocar site. In the postSeprafilm group the membrane was placed at each site before injection of tumor cells. The control group did not receive Seprafilm. The animals were killed after seven weeks, and the abdominal wound sites were excised. Sites without gross tumor underwent histologic evaluation.

RESULTS

One hundred thirty-two animals were randomly assigned to the three groups. The preSeprafilm group had an 87 percent tumor implantation rate. The postSeprafilm group had a 90 percent tumor implantation rate. The control group had an 88 percent tumor implantation rate. Chi squared analysis demonstrated that these total tumor implant rates and mean tumor mass were similar at all wound sites and between groups. No toxicity was observed in any of the experimental groups.

CONCLUSIONS

Sodium hyaluronate-based bioresorbable membrane (Seprafilm) does not influence GW-39 human colon cancer implantation at abdominal wound sites in this hamster model.

Clinical and radiologic assessment of laparoscopic paraesophageal hernia repair

BACKGROUND

Unlike sliding hiatal hernias, paraesophageal hiatal hernias (PEH) present a risk of catastrophic complications and should be repaired. To assess laparoscopic repair of PEH, we prospectively evaluated the outcome of 38 consecutive patients with type II (20 patients) or III (18 patients) PEH treated laparoscopically.

METHODS

With the use of 5 or 6 ports, laparoscopic PEH reduction and repair was attempted. One patient (3%) was converted to an open procedure. In the first 12 patients, the hiatus was closed using varying techniques including the placement of prothestic mesh in 6 patients, and the hernia sac was not routinely excised. In the next 25 patients, the hernia sac always was excised and the hiatus routinely sutured posteriorly to the esophagus. Twenty-nine patients also underwent either a Nissen (n = 27) or Toupet (n = 2) fundoplication, which is now performed routinely. Sutured anterior gastropexy was performed selectively in 10 of the first 20 patients, then routinely, using T-fasteners in the last 17 patients. Barium swallow studies were performed on all patients at 3 to 5 months postoperatively.

RESULTS

Mean +/- standard error of the mean (SEM) age was 67 +/- 2 year (range, 39-92 years; 11 men, 27 women), and the American Society of Anesthesia (ASA) score was 2.5 +/- 0.1. The operating time was 195 +/- 10 min: 244 +/- 15 min in the first 12 patients and 170 +/- 11 min in the last 25 patients (p < 0.001). There were three (8%) intraoperation complications, which were treated without sequelae, and four (11%) grade II postoperation morbidities. Median discharge was 3 days, and return to full activity was 14 days. Two patients (5%) died of cardiovascular disease after discharge. Barium swallow revealed 2/35 (6%) PEH recurrences (1 reoperated), 3 (9%) intrathoracic wraps, and 3 (9%) small sliding hiatal hernias. At follow-up of 1 year or more, 6/28 (21%) patients noted mild symptoms of reflux or bloating, but only 1 patient (4%) required medication for these symptoms.

CONCLUSIONS

Laparoscopic PEH repair offers a reasonable alternative to traditional surgery, especially for high-risk patients. Rapid recovery is achieved with acceptable morbidity and early outcome. Barium x-rays revealed hiatal abnormalities in a significant fraction of patients, many of whom were asymptomatic. Longer follow-up will be required to determine the ideal strategy for management of these patients.

[Quantification of female teenagers' competence of sexual cognition]

Compiling a questionnaire of sexual cognition for surveying 224 female teenagers (11 to 14 years old), the results showed that they were deficient in the knowledge of sexual physiology, mortality and law. And also, the deficiency had a high co-relationship with the age of surveyed female teenagers. It suggested that this questionnaire be valuable in the quantification of sexual cognition.

Randomized comparison of laparoscopic and open lymphadenectomy in pigs

OBJECTIVE

To compare the efficacy of open and laparoscopic lymphadenectomy and validate an objective model of lymph node retrieval using lymphangiography in pigs.

METHODS

Twenty-five pigs weighing 54-75 lbs were randomly assigned by side to open or laparoscopic pelvic and paraaortic lymphadenectomy. Lymph node yield, quantified by a masked pathologist, operative time, complications, blood loss, and other variables were recorded. Lymphangiography was done, and radiographs were taken before and after lymph node harvesting. Statistical analysis used McNemar test for nominal data and paired Student t test or Wilcoxon signed-rank test for continuous variables.

RESULTS

Lymph node yields were a mean of 11.5 with a standard deviation of 2.8 for open and 15.3 +/- 3.4 nodes for laparoscopic lymphadenectomy (P = .009). Mean operating time was 26.5 +/- 5.3 minutes for open versus 54.9 +/- 23.7 minutes for laparoscopy (P < .01). Mean blood loss was higher for laparoscopic cases, 35 mL for open versus 58 mL for laparoscopic lymphadenectomy (P = .048). The four major complications were evenly distributed between the two procedures. Lymphangiography was successful in 24 of 25 pigs. A total of 243 lymph nodes were identified with equal distribution by side. Lymphangiographic data correlated well with number of lymph nodes retrieved.

CONCLUSION

In this randomized trial, laparoscopic lymphadenectomy was at least as effective as open lymphadenectomy, although operating time and blood loss were greater. Lymphangiography was a reliable, objective mode for documentation and assurance of lymph node recovery.

Sympathetic hyperactivity in Wistar rats with insulin-resistance

In an attempt to know the effect of sustained hyperinsulinemia on sympathetic function, plasma norepinephrine (NE) and glucose levels were measured in Wistar rats with insulin resistance. Both the basal plasma glucose and the plasma NE levels in insulin-resistant rats were markedly higher than that obtained in normal or streptozotocin (STZ)-induced diabetic rats. Treatment with guanethidine and prazosin reversed these sympathetic hyperactive responses in insulin-resistant rats. Moreover, increase of plasma insulin in rats receiving an intraperitoneal glucose challenge test confirmed the mediation of endogenous insulin in this sympathetic hyperactivity. These results suggest an increase of sympathetic activity in insulin-resistant state that may be related to the hypertension-prone associated with diabetes mellitus in clinics.