A novel surface modification scheme for ITO nanocrystals by acetylene: a combined experimental and DFT study

The chemisorption of C₂H₂ molecules on the ITO(100) surface results in ethylene-like configurations as studied by DFT and experiment.

IgG avidity assay: a tool for excluding acute toxoplasmosis in prolonged IgM titer sera from pregnant women

An accurate diagnosis for toxoplasmosis is crucial for pregnant women as this infection may lead to severe sequelae in the fetus. The value of IgG avidity assay as a tool to determine acute and chronic toxoplasmosis during pregnancy was evaluated in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). In this study, 281 serum samples from 281 pregnant women in various trimesters were collected. These samples were assayed using specific anti-Toxoplasma IgM and IgG antibodies, followed by IgG avidity test. The overall seroprevalence of toxoplasmosis in pregnant women was 35.2% (33.5% for anti-Toxoplasma IgG and 1.8% for both anti-Toxoplasma IgG and IgM antibodies). Of 5 (1.8%) serum samples positive for IgM ELISA, 4 had high-avidity antibodies, suggesting past infection and one sample with borderline avidity index. Two samples with low avidity were from IgM negative serum samples. The IgG avidity assay exhibited an excellent specificity of 97.6% and a negative predictive value (NPV) of 95.6%. The study also demonstrated no significant correlation between avidity indexes of the sera with IgG (r=0.12, p=0.24) and IgM (r=-0.00, p=0.98), suggesting the complementary needs of the two tests for a better diagnosis outcome. These findings highlight the usefulness of IgG avidity assay in excluding a recently acquired toxoplasmosis infection in IgM-positive serum sample.

AN ANALYSIS OF CAUSES AND TREATMENT OUTCOME OF CHRONIC WRIST PAIN AFTER DISTAL RADIAL FRACTURES

Healed distal radial fractures are frequently complicated by chronic wrist pain which is multifactorial and can be debilitating. An accurate delineation of the pathoanatomy is the key for successful treatment. This study reviewed 22 patients who had surgical treatment between 1997 and 2001 for chronic wrist pain after distal radial fracture. Four patterns of pathoanatomy were identified: (1) ulnar impaction caused by radial malunion and shortening; (2) ulnar styloid non-union; (3) triangular fibrocartilage complex (TFCC) tears with or without distal radioulnar joint (DRUJ) instability; and (4) intercarpal ligament injuries and chondral lesions. Surgical treatment directed towards identified abnormalities gave satisfactory outcome. At six months after surgery the mean functional score improved 36%, mean pain score decreased 50%, mean grip strength improved 25%, and 64% of patients returned to work.

Surgical excision for challenging upper limb nerve sheath tumours: a single centre retrospective review of treatment results

OBJECTIVE

To review the accuracy of different investigation modalities for upper limb nerve sheath tumours and the resulting surgical outcomes, and propose a standard algorithm to deal with such tumours to minimise complications.

DESIGN

Retrospective review.

SETTING

Regional hospital, Hong Kong.

PATIENTS

All patients with upper limb nerve sheath tumours being excised in our hospital from 1999 to 2008.

MAIN OUTCOME MEASURES

The accuracy rate of different investigations, as well as corresponding neurological deficits after excision and recurrence rates.

RESULTS

A total of 23 (10 male and 13 female) patients, aged between 28 and 72 (mean, 46) years, underwent excision of 25 lesions during the study period. The mean duration of symptom was 2.5 years and tumour size ranged from 1 to 10.5 cm (mean, 2.6 cm). A majority (80%) presented with a typical triad; only one had a true neurological deficit. Twenty-two ultrasonography and 20 magnetic resonance images were obtained, with a diagnostic accuracy of 77% and 100%, respectively. Eight fine-needle aspiration cytology examinations and two core biopsies were performed, which had respective accuracy rates of 13% and 100%. Fifteen patients experienced neurological deficits after the operation; three showed spontaneous recovery. Among 12 patients with long-term residual neurological sequelae, five had both motor and sensory deficits and four had moderate-to-severe disability. No recurrence was reported.

CONCLUSION

Nerve sheath tumours in the hand need to be managed with care. Among the different investigation modalities, magnetic resonance imaging was considered to be the gold standard. Yet ultrasonography is still the most easily accessible and least invasive investigation in public hospital setting. Complications are liable to ensue even if patients are managed by hand specialists. Thus, well-planned operations and detailed discussions with the patient are important prerequisites before operation.

Needle aponeurotomy for Dupuytren's contracture

PURPOSE

To review the efficacy and safety of needle aponeurotomy for Dupuytren's contracture in Chinese patients.

METHODS

Seven men and one woman aged 50 to 80 (mean, 67) years underwent needle aponeurotomy for Dupuytren's contracture. Five were manual workers and the other 3 were retired. Their chief complaints were difficulty moving the fingers, clumsiness of the hand, and occasional pain in the palm. No patient had any family history of Dupuytren's contracture.

RESULTS

41 points were released in 13 fingers (3 middle, 3 ring, and 7 little). Immediately after release, the respective mean flexion contracture correction of the metacarpophalangeal and proximal interphalangeal joints were 50 (from 50 to 0) and 35 (from 46 to 11) degrees. At 22-month follow-up, the respective mean residual flexion contracture of both joints were 12 and 27 degrees; the corresponding long-term improvements were 70 and 41%. No patient had a wound complication or neurovascular injury. All had a normal score for Disabilities of the Arm, Shoulder, and Hand.

CONCLUSION

For Chinese patients with Dupuytren's contracture, needle aponeurotomy is safe and effective. Long-term correction is better maintained in metacarpophalangeal than proximal interphalangeal joints (70 vs 41%).

Spontaneous fractures in nursing home residents

OBJECTIVES

To evaluate spontaneous long bone fractures occurring in nursing home residents and to identify what factors put them at risk for fractures.

DESIGN

Retrospective study.

SETTING

Department of Orthopaedics and Traumatology of a pubic hospital in Hong Kong.

PATIENTS

A total of 30 nursing home residents who developed spontaneous long bone fractures between 1994 and 2005 were reviewed.

MAIN OUTCOME MEASURES

Demographic data, mechanism of injury, pattern of fractures, associated risk factors, complications, outcomes, and post-treatment status.

RESULTS

The mean age of patients was 84 years. Co-morbidities were as follows: 22 patients were bedridden, 21 required long-term feeding by Ryle's tube, 19 had a history of cerebrovascular accident and 18 of whom had a long bone fracture on the side of the hemiplegia, 15 had dementia, and 25 had lower limb contractures. Closed supracondylar fractures of the femur occurred in 23 patients, 17 of whom presented with limb deformity. In 21 patients, fractures were treated successfully with hinged braces. In one patient, the fracture changed from closed to open. In five patients, the fractures were complicated by sacrum or heel sores, and in one by infected nonunion. In 28 patients, the fractures eventually healed without further complications. Three formerly bedridden patients were able to sit after their fractures had been treated.

CONCLUSIONS

Female nursing home residents who require long-term Ryle's tube feeding, have dementia, hemiplegia, lower limb contractures, osteoporosis, or are bedridden, are at high risk for spontaneous fractures.

Two new chemical constituents fromDaphne odoraThunb. var.marginata

Two new phenolic constituents, daphnenone (1) and daphneone (2), were isolated from the stem bark of Daphne odora Thunb. var. marginata. Their structures were established on the basis of spectroscopic analysis. Compounds 1 and 2 were tested for cytotoxic activity by MTT assays on five human tumour cell lines, K562, A549, MCF-7, LOVO and HepG2. Compound 1 showed obvious cytotoxic activity against all the five cell lines.

Hematological effects of Blastocystis hominis infection in male foreign workers in Taiwan

Blastocystis hominis found in stool specimens has been the most frequently identified parasite among foreign workers from Southeast Asia in Taiwan since 1992. The prevalence of B. hominis was 14.1% in this study. In their quarantine physical examinations, 121 male Thai workers were examined hematologically and screened for stool parasites using the merthiolate-iodine-formaldehyde concentration method. Hematological values were compared in workers with and without a B. hominis infection. Multiple regressions were used to adjust for age. Those infected with any parasite other than B. hominis were excluded from further analysis. The workers infected with B. hominis had a lower leukocyte count (6.5+/-0.4 X 10(3)/microl) than those who were not (7.4+/-0.2 X 10(3)/microl). This was mainly caused by a reduced neutrophil count (3.2+/-0.4 vs 4.2+/-0.2 X 10(3)/microl). Hemoglobin (13.9+/-0.3 vs 14.5+/-0.1 g/dl) and hematocrit (41.4+/-0.6 vs 42.9+/-0.2%) were also reduced in B. hominis-positive workers.

Performance of elbow tracking under constant torque disturbance in normotonic stroke patients and normal subjects

OBJECTIVE

In this study, the influences of externally imposed constant torque on the voluntary elbow movements of stroke and normal subjects were investigated quantitatively.

BACKGROUND

Muscle weakness, spasticity and incoordination are the major factors that interfere with stroke patient's limb functions. Imposing external torque disturbance may worsen the motor performance. This experiment was designed to investigate the effects of small constant external torque on the performance of voluntary elbow movements.

METHODS

Tracking of a ramp-and-hold angle trajectory in the direction of extension was used as the main task for performance assessment. Each subject repeated the same tracking movement six times in each of three loading conditions: no, assistive or resistive loading. Five normal and six stroke subjects were recruited for this study. We used parameters extracted from movement trajectory and processed electromyograms as the performance indicators.

RESULTS

For normal subjects, there was no difference in the tracking performance in the three loading conditions. For stroke patients, the affected side had inferior performance to the healthy side in the free loading condition and the difference diminished in assistive and resistive loading conditions as the performance of the affected side improved. Integrated electromyograms of biceps or triceps did not show significant changes in different loading conditions.

CONCLUSIONS

Small externally imposed constant torque, either resistive or assistive, may improve motor performance of affected elbows in stroke patients.

RELEVANCE

Most of the currently available prostheses are passive devices, aiming at providing better support and improving stability. The results of the current study imply that an active prosthetic device that applies a small constant torque to the hemiparetic elbow can improve its motor performance in stroke patients. The direction of external torque is to assist the weaker side of the antagonistic muscle pair.

Estimating stature from knee height for adults in Taiwan

BACKGROUND

Many of the indices utilized in the assessment of nutritional status are dependent upon stature. Knee height has been used to predict stature in western countries when standing height cannot be measured, however, an adequate stature-knee height equation has not been established for the population in Taiwan.

METHODS

A total of 1179 healthy men (603) and women (576) were recruited from those who had undergone comprehensive check-ups at their own expense from March through August 1998 at Lin-Kou Chang-Gung Memorial Hospital, Taiwan. The subjects were freely ambulatory without kyphosis or scoliosis noted on their chest X-ray or KUB films. The automatic supersonic system was used to measure stature and body weight. A Ross caliper was used to measure recumbent left knee height. Multiple linear regression was used to obtain equations to estimate stature using knee height and age.

RESULTS

Stature of adults highly correlated with their knee height (r = 0.73 with 95%CI between 0.69 and 0.77 for men, and r = 0.68 with 95%CI between 0.63 and 0.72 for women) but declined with age (men: r = -0.17 with 95%CI between -0.09 and -0.24; women: r = -0.22 with 95%CI between -0.14 and -0.29). Knee height changed very little with age in both genders. To predict stature, a linear regression model should include knee height and age as predictors to reach r2 as 0.61 and 0.58 for men and women, respectively. The stature-knee height equations were "stature = 85.10 + 1.73 x knee height -0.11 x age" for men, "stature = 91.45 + 1.53 x knee height -0.16 x age" for women.

CONCLUSION

Our stature-knee height equations provided good predictions on stature of adult population in Taiwan, and was superior when compared with equations developed from other populations.

Diverse cyclization catalyzed by In(OTf)3 for the convergent assembly of substituted tetrahydrofurans and tetrahydropyrans

[reaction: see text]. A novel In(OTf)3-catalyzed (3,5) oxonium-ene type cyclization for the facile construction of various multisubstituted tetrahydrofurans and tetrahydropyrans was successfully developed. Further mechanistic investigations unveiled an In(OTf)3-catalyzed skeletal reorganization of the tetrahydrofuran to its thermodynamic isomer under thermal conditions.

Skin care in burn patients: a team approach

Skin care is an important but often neglected issue in burn management. Newly healed burn skin is fragile, itchy, dry, and susceptible to sunburn. Without proper skin care in burn patients, they may suffer from sleep and mood disturbances, depression, and poor compliance to treatment that can jeopardize the rehabilitation process. At the Prince of Wales Hospital, skin care has been managed since February 1996 by a team consisting of plastic surgeon, dermatologist, occupational therapist and nursing specialist. The purpose of this study was to evaluate the impact of a skin care program run by a Skin Care Team on the rehabilitation of burn patients in a tertiary burn centre. The role of different members of the team was also discussed.

Investigation on subclinical aspects related to intestinal parasitic infections among Thai laborers in Taipei

BACKGROUND

The migration of foreign workers from developing regions to developed countries may potentially lead to transmission of intestinal parasitic infections. In order to determine the relationship between intestinal parasitic infections and the health status of foreign workers, 302 Thai laborers brought to Taiwan were examined in this study. Nine species of parasites were found in 64.9% of laborers; Opisthorchis viverrini, hookworm, Strongyloides stercoralis, Giardia lamblia, Trichuris trichiura, Fasciolopsis buski, Taenia sp, Echinostoma sp, Entamoeba coli.

METHODS

From June 1992 to December 1993, a total of 302 Thai laborers, participating in the mandatory entry health examination at Chang-Gung Memorial Hospital, Lin-Kou Medical Center were interviewed and examined. These subjects underwent a physical examination, chest roentgenography, and serological tests for human immunodeficiency virus antibody, syphilis (VDRL), and hepatitis B surface antigen.

RESULTS

Among the 302 Thai laborers examined, 196 (64.9%) were found to be infected with 1 to 5 species of parasites. All 193 infected Thai laborers were treated in Taiwan. Two or 3 courses of pyrantel pamoate, mebendazole, praziquantel, and metronidazole were administered to 119, 45, 24, and 5 infected patients respectively. After 1 week of treatment, all results of stool examinations were negative.

CONCLUSION

Acquisition of infection has been determined to be related to the consumption of koipla, a dish prepared from uncooked freshwater fish. Not unexpectedly, in the present study, it was found that this species was the most important intestinal parasite among Thai laborers and was significantly associated with the consumption of koipla.

Outbreak investigation of nosocomial enterobacter cloacae bacteraemia in a neonatal intensive care unit

Over a period of 7 months, 23 patients hospitalized in a neonatal intensive care unit (NICU) developed nosocomial Enterobacter cloacae bacteraemia. Contaminated saline for preparing heparin solution was initially identified as the common source of E. cloacae bacteraemia. Although environmental sanitation was enforced, the outbreak continued. E. cloacae has always been isolated from various cultures of the environmental specimens, from the hands of personnel and from the faeces of patients. All of the 23 bacteraemic isolates and 8 stool isolates from infected infants, as well as the 17 isolates from environmental specimens were found to be of the same genotype using the polymerase chain reaction-based DNA fingerprinting method. After various infection control methods were instituted, the outbreak eventually came under control. For epidemiological investigation, 23 neonates without E. cloacae bacteraemia were matched for case-control study. Nineteen (83%) of the case-patients were premature. The significant risk factors leading to E. cloacae bacteraemia in the NICU included small gestation age, low birthweight, exposure to personnel with contaminated hands and the presence of E. cloacae in the stool carriage (p=0.003, 0.007, 0.018 and 0.040, respectively). The gastrointestinal tracts of the patients and environmental surfaces appeared to be the principal sites of bacterial reservoir. In conclusion, the outbreak of E. cloacae bacteraemia was caused by a particular strain and possibly via multiple modes of transmission, including a bottle of contaminated saline as an initial common source, endogenous spread from the gastrointestinal tract and successive cross-infections between patients, hands of personnel and the environment. Effective infection control requires a multidisciplinary approach and reinforcement of infection control procedures, including aseptic technique, hand washing, proper isolation and disinfection of environmental surfaces.

The clinical features and prognosis of lupus with disease onset at age 65 and older

Systemic lupus erythematosus (SLE) in the elderly is uncommon and rarely reported with disease onset at age 65 and older. The aim of this study is to retrospectively analyze the influence of age at disease onset on the clinical features and prognosis of SLE. From 1988 to 1998, we encountered 21 lupus patients with disease onset at age 65 and older (all are included in group A). For comparison, 21 lupus patients with disease onset between 50-64 years of age (group B) and 152 lupus patients with disease onset before 50 years of age (group C) were obtained by a simple random sampling method from the hospital registry. Clinical features as included in the 1982 ARA revised criteria for classification of SLE and survival rate were analyzed and compared among these three groups. Group A had a smaller female to male ratio, longer duration from disease onset to diagnosis, less malar rash, more discoid lupus, and shorter survival rate that group C. There was no statistically significant difference in clinical features and survival between groups A and B, as well as between female and male patients of these two groups. The main cause of death in group A was septic shock. In conclusion, the clinical features and prognosis of SLE were influenced by the age at disease onset. However, clinical features and prognosis of SLE were similar in both late-onset lupus groups.

Modulation of Ca2+-dependent anion secretion by protein kinase C in normal and cystic fibrosis pancreatic duct cells

The study investigated the role of protein kinase C (PKC) in the modulation of agonist-induced Ca2+-dependent anion secretion by pancreatic duct cells. The short-circuit current (ISC) technique was used to examine the effect of PKC activation and inhibition on subsequent ATP, angiotensin II and ionomycin-activated anion secretion by normal (CAPAN-1) and cystic fibrosis (CFPAC-1) pancreatic duct cells. The ISC responses induced by the Ca2+-mobilizing agents, which had been previously shown to be attributed to anion secretion, were enhanced in both CAPAN-1 and CFPAC-1 cells by PKC inhibitors, staurosporine, calphostin C or chelerythrine. On the contrary, a PKC activator, phorbol 12-myristate 13-acetate (PMA), was found to suppress the agonist-induced ISC in CFPAC-1 cells and the ionomycin-induced ISC in CAPAN-1 cells. An inactive form of PMA, 4alphad-phorbol 12, 13-didecanote (4alphaD), was found to exert insignificant effect on the agonist-induced ISC, indicating a specific effect of PMA. Our data suggest a role of PKC in modulating agonist-induced Ca2+-dependent anion secretion by pancreatic duct cells. Therapeutic strategy to augment Ca2+-activated anion secretion by cystic fibrosis pancreatic duct cells may be achieved by inhibition or down-regulation of PKC.

Amoebiasis among institutionalized psychiatric patients in Taiwan

Although information on amoebiasis among institutionalized psychiatric patients is available, reports on the relationship between behaviour and this infection are not abundant. From July 1995 to June 1996, stool and blood samples were collected from 565 patients in three psychiatric hospitals of North Taiwan. Stool samples were examined using the direct smear and formalin-ethyl acetate sedimentation techniques as well as ProSpecT Entamoeba histolytica Microplate Assay kit. Blood samples were examined by the Amebiasis Serology Microwell ELISA kit. Among these patients, 14 (2.5%) harboured one or two species of intestinal parasites. There were 6 (1.1%) E. histolytica/E. dispar cyst passers: 5 positive in stool ELISA test and 2 with antibodies against E. histolytica. Among demographic factors, type of psychiatric disorder and disability, only a significant sexual difference in seropositivity of E. histolytica was observed. These findings indicate that the infected patients acquired the infections before they entered the hospitals.

Angiotensin II-mediated signal transduction events in cystic fibrosis pancreatic duct cells

Different signal transduction pathways, i.e. Ca2+- and cAMP-dependent, involved in mediating the effects of angiotensin II (AII) were investigated separately using the short-circuit current (Isc) technique and radioimmunoassay (RIA) in a cystic fibrosis pancreatic cell line (CFPAC-1) which exhibits defective cAMP-dependent but intact Ca2+-dependent anion secretion. The AII-induced Isc could be inhibited by the specific antagonist for AT1, losartan (1 microM), but not the antagonist for AT2, PD123177 (up to 10 microM). The AII-induced Isc was also reduced by the treatment of the cells with a Ca2+ chelator, BAPTA-AM (100 microM), indicating a dependence of the AII-induced anion secretion on the intracellular Ca2+. Treatment of the cells with pertussis toxin (0.1 microg/ml) or a phospholipase C (PLC) inhibitor, U73122 (5 microM), resulted in a substantial reduction in the AII-induced Isc indicating involvement of Gi and PLC in the Ca2+-dependent anion secretion. RIA measurements showed that AII stimulated an increase in cAMP production which could be reduced by losartan, pertussis toxin and U73122 but not BAPTA-AM. In addition, inhibitors of cyclooxygenase, indomethacin (10 microM) and piroxicam (10 microM), did not have any effect on the AII-induced cAMP production, excluding the involvement of prostaglandins. Our results suggest that both AII-stimulated cAMP and Ca2+-dependent responses are mediated by the AT1 receptor and Gi-coupled PLC pathway. However, the AII-stimulated cAMP production in CFPAC-1 cells is not dependent on Ca2+ or the formation of prostaglandins.

Concurrent and independent HCO3- and Cl- secretion in a human pancreatic duct cell line (CAPAN-1)

The present study investigated both HCO-3 and Cl- secretions in a human pancreatic duct cell line, CAPAN-1, using the short-circuit current (Isc) technique. In Cl-/HCO-3-containing solution, secretin (1 microM) or forskolin (10 microM) stimulated a biphasic rise in the Isc which initially reached a peak level at about 3 min and then decayed to a plateau level after 7 min. Removal of external Cl- abolished the initial transient phase in the forskolin-induced Isc while the plateau remained. In HCO-3/CO2-free solution, on the contrary, only the initial transient increase in Isc was prominent. Summation of the current magnitudes observed in Cl--free and HCO-3-free solutions over a time course of 10 min gave rise to a curve which was similar, both in magnitude and kinetics, to the current observed in Cl-/HCO-3-containing solution. Removal of external Na+ greatly reduced the initial transient rise in the forskolin-induced Isc response, and the plateau level observed under this condition was similar to that obtained in Cl--free solution, suggesting that Cl--dependent Isc was also Na+-dependent. Bumetanide (50 microM), an inhibitor of the Na+-K+-2Cl- cotransporter, and Ba2+ (1 mm), a K+ channel blocker, could reduce the forskolin-induced Isc obtained in Cl-/HCO-3-containing or HCO-3-free solution. However, they were found to be ineffective when external Cl- was removed, indicating the involvement of these mechanisms in Cl- secretion. On the contrary, the HCO-3-dependent (in the absence of external Cl-) forskolin-induced Isc could be significantly reduced by carbonic anhydrase inhibitor, acetazolamide (45 microM). Basolateral application of amiloride (100 microM) inhibited the Isc; however, a specific Na+-H+ exchanger blocker, 5-N-methyl-N-isobutylamiloride (MIA, 5-10 microM) was found to be ineffective, excluding the involvement of the Na+-H+ exchanger. However, an inhibitor of H+-ATPase, N-ethylmaleimide did suppress the Isc (IC50 = 22 microM). Immunohistochemical studies also confirmed the presence of a vacuolar type of H+-ATPase in these cells. H2DIDS (100 microM), an inhibitor of Na+-HCO-3 cotransporter, was without effect. Apical addition of Cl- channel blocker, diphenylamine-2,2'-dicarboxylic acid (DPC, 1 mm), but not disulfonic acids, DIDS (100 microM) or SITS (100 microM), exerted an inhibitory effect on both Cl- and HCO-3-dependent forskolin-induced Isc responses. Histochemical studies showed discrete stainings of carbonic anhydrase in the monolayer of CAPAN-1 cells, suggesting that HCO-3 secretion may be specialized to a certain population of cells. The present results suggest that both HCO-3 and Cl- secretion by the human pancreatic duct cells may occur concurrently and independently.

Erythrocyte Ca2+ pump is defective during sepsis

Saturated Ca2+ extrusion rate through the Ca2+ pump of erythrocytes was determined by the cobalt-exposure method in normal subjects and septic patients. From 48 normal subjects, the value of Vmax of erythrocyte Ca2+ pump was 14.83 +/- 0.49 mmol/L cells/hr; from 29 sepsis patients, it was 9.49 +/- 0.59 mmol/L cels/hr, significantly (P < 0.001) lower than that from the erythrocytes of normal subjects. When the severity of sepsis was evaluated by the septic severity score (SSS), a significant correlation (P < 0.0001) was observed between the Vmax of Ca2+ pump and the patient's SSS, indicating that the inhibition of Ca2+ pump depended on the degree of the pathological development of sepsis. Since the ATP-dependent Ca2+ transport in rat liver plasma membrane is also reduced during the late stage of sepsis [Lau et al., Circ Shock 38:238-244, 1992], impairment of the activity of Ca2+ pump appears to have a general pathophysiological significance in the development of severe sepsis.

Prevalence of genital human papillomavirus infections in patients at a sexually transmitted diseases clinic

The human papillomavirus was detected in cervicovaginal cells by the polymerase chain reaction in 14 of 37 (37.8%) patients attending a sexually transmitted disease (STD) clinic and in 6 of 43 healthy young women (14.0%) undergoing routine gynecologic examinations who served as controls. The results indicated that even the more malignant types of human papillomaviruses were not uncommon among the control group, and that the prevalence of human papillomavirus infection was significantly higher in STD clinic patients than in the control group. These findings confirm the suggestion that factors other than human papillomavirus infections may be involved in the pathogenesis of cervical cancer.

Creatine kinase MB elevation in paralytic shellfish poisoning

An outbreak of paralytic shellfish poisoning occurred in southern Taiwan, affecting 116 persons who had consumed purple clams. Two victims died within four hours. Gonyautoxins were identified as causative toxins. During the outbreak, five patients with paralytic shellfish poisoning were seen in our hospital. All recovered following supportive treatments. Serum creatine kinase concentration was elevated in three of the five patients. The levels of the enzyme did not seem to correlate with the severity of poisoning. The most significant finding was the previously unreported observation of elevation of the creatine kinase MB level. In all four patients who had creatine kinase MB value determined, it was elevated.

The essential role of a poison center in handling an outbreak of barium carbonate poisoning

Acute barium salt poisoning may cause acute hypokalemia and result in respiratory paralysis and ventricular tachyarrhythmias. The early nonspecific gastrointestinal symptoms of barium poisoning due to food contamination could be confused with other benign food poisonings. Early diagnosis and initiation of intensive supportive care is essential. We report an outbreak of acute barium carbonate poisoning, occurring at a family reunion party, which resulted in 9 hospital admissions. All of the victims initially developed nausea, vomiting, abdominal colic, dizziness and watery diarrhea followed by numbness of the face and distal extremities 1-2 h after ingesting fried flour-coated sweet potatoes. The flour was later confirmed to be contaminated with barium carbonate. One person died in the emergency room with a serum potassium level of 0.8 mEq/L. Two other victims developed ventricular tachycardia and respiratory paralysis but completely recovered with the treatment advice provided by the poison center. The poison center was successful in helping to make the correct diagnosis in a timely manner, immediately distribute the treatment protocol, and coordinate the laboratory confirmation of barium carbonate poisoning.

Application of Average Flow Model to Lubrication Between Rough Sliding Surfaces

The Average Flow Model introduced in an earlier paper is extended to include sliding contacts by deriving the shear flow factor for various roughness configurations. Similar to the pressure flow factors, the shear flow factor is obtained through numerical flow simulation on a model bearing having numerically generated roughness. The flow factors for isotropic and directional surfaces are expressed as empirical relationships in terms of h/σ, a surface pattern parameter γ defined as the ratio of x and y correlation lengths, and the variance ratio Vr1 which is the ratio of variance of surface 1 to that of the composite roughness. Expressions for the mean shear stress and horizontal force components due to local pressure in rough bearings are derived through the definition of shear stress factors, also obtained through simulation. The application of the average Reynolds equation to analyze roughness effects in bearings is demonstrated on a finite slider. The effects of the operating parameters as well as the roughness parameters on mean hydrodynamic load, mean viscous friction and mean bearing inflow are illustrated.

An Average Flow Model for Determining Effects of Three-Dimensional Roughness on Partial Hydrodynamic Lubrication

A new approach is utilized to determine the effects of surface roughness on partially lubricated contacts. An average Reynolds equation for rough surfaces is defined in terms of pressure and shear flow factors, which are obtained by numerical flow simulation. Through the use of measured or numerically generated rough surfaces, any three dimensional roughness structure can be analyzed with this method. The average Reynolds equation is obtained for isotropic surfaces, and for surfaces with directional patterns. The flow factors for these surfaces are expressed as empirical relations in terms of h/σ and a surface characteristic γ defined as the ratio of x and y correlation lengths.

Pressure Perturbation in EHD Contacts Due to an Ellipsoidal Asperity

The pressure fluctuations around an ellipsoidal asperity tip at the inlet region of an elastohydrodynamic contact is determined by solving a perturbed Reynolds equation assuming that the asperity shape is unaffected by the perturbed pressure. Results are presented as the amplitude of the perturbed pressure as a function of ellipticity ratio, maximum Hertzian pressure, nominal EHD film thickness, asperity size, asperity height, and pressure viscosity coefficient. For the case of simple sliding between a smooth surface and a stationary asperity, a comparison is also made between the results for large ellipticity ratios and the pressure fluctuations obtained by using a previous line contact EHD analysis [6] for a two-dimensional asperity ridge. The agreement is found to be close for moderate Hertzian pressure and relatively thick EHD film thickness.

The Effect of Surface Roughness on the Average Film Thickness Between Lubricated Rollers

The Christensen theory of stochastic models [7] for hydrodynamic lubrication of rough surfaces is extended to elastohydrodynamic lubrication between two rollers. The Grubin-type equation including asperity effects in the inlet region is derived. Solutions for the reduced pressure at the entrance as a function of the ratio of the average nominal film thickness to the r.m.s. surface roughness (in terms of standard deviation σ), have been obtained numerically. Results were obtained for purely transverse as well as purely longitudinal surface roughness for cases with or without slip. The reduced pressure is shown to decrease slightly by considering longitudinal surface roughness. The transverse surface roughness, on the other hand, has a slight beneficial effect on the average film thickess at the inlet. The same approach was used to study the effect of surface roughness on lubrication between rigid rollers and lubrication of an infinitely-wide slider bearing. Results of these two cases show that the effects of surface roughness are similar to those found in elastohydrodynamic contacts.

The Pressure and Deformation Profiles Between Two Normally Approaching Lubricated Cylinders

The pressure and deformation profiles between two colliding lubricated cylinders are obtained by solving the coupled, time-dependent elastohydrodynamic equations with an iterative procedure. The analysis includes several effects which were not considered in a previous solution by Christensen [4], namely, the effect of surface velocities due to local deformation, the effect of the lubricant compressibility, and the effect of a lubricant with composite pressure-viscosity coefficients. It is found that the local approach velocity plays an important role during final stages of normal approach. It causes the lubricant to be entrapped within the contact region, and both the pressure and deformation profiles appear to converge to the Hertzian profile. The use of a smaller pressure-viscosity coefficient at high pressures reduces the sharp pressure gradient at the center of the contact, and produces a much milder variation of load with respect to the film thickness. The effect of compressibility of the lubricant is found to be relatively small.

Isothermal Elastohydrodynamic Theory for the Full Range of Pressure-Viscosity Coefficient

The isothermal, elastohydrodynamic (EHD) solutions in the inlet region of line contacts are extended to cover the full range of pressure-viscosity parameter, G, and the region of extremely heavy loads. The effect of a composite exponential model for the pressure-viscosity dependence on the film thickness is also studied. Results of the film thickness are compared with those based on work by Grubin, Dowson-Higginson, Bell and Kannel, and Herrebrugh. Comparison is also made between the theoretical results with the recently obtained X-ray film thickness measurements.