Cytological distinction between high-risk and low-risk human papillomavirus infections in SurePath liquid-based cell preparations

AIMS

To investigate the correlation of various diagnostic cytological features in SurePath liquid-based cell preparations with high-risk human papillomavirus (HPV) infection.

METHODS

Case-control study. SurePath specimens from 510 cases that had been tested for HPV DNA by Hybrid Capture 2 assay were retrieved and re-examined for 10 cytological features. Distribution of these features in high- and low-risk HPV types was compared and risk statistics were estimated. Effects of cervicitis on the manifestation of HPV cytological changes were adjusted by means of logistic regression.

RESULTS

Cytological features of nuclear hyperchromasia, multinucleation and atypical metaplastic cells were predominantly noted in high-risk HPV infection in the category of atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion. The odds ratios of these three features were 6-12 times higher in high-risk than low-risk HPV infection.

CONCLUSIONS

Some diagnostic cytological features can be used as markers in Pap smear screening for assessing the types of HPV infection.

Altered osmotic swelling behavior of proteoglycan-depleted bovine articular cartilage using high frequency ultrasound

Swelling behavior is an electrochemical mechanical property of articular cartilage. It plays an important role in weight bearing and joint lubrication. In this study, the altered transient and inhomogeneous swelling behavior of the degenerated articular cartilage was observed and quantified in situ using ultrasound. Three groups of bovine patellar articular cartilage samples (n = 10 x 3) were obtained and digested by trypsin for 10, 20 and 30 min respectively to mimic different levels of degeneration. The osmotic-free shrinkage and swelling behavior induced by changing the concentration of the bathing saline solution from 0.15 M to 2 M and then back to 0.15 M were characterized using high-frequency ultrasound (central frequency = 35 MHz) before and after digestion. It was found that the degenerated cartilage specimens showed a weaker shrinkage-swelling behavior compared with the normal cartilage samples. However, no significant differences in the peak shrinkage or swelling strains were observed between different groups. The absolute values of the peak shrinkage strain significantly (p < 0.05) decreased by 45.4%, 42.1% and 50.6% respectively after the trypsin digestion for 10, 20 and 30 min, but such significance was not demonstrated for the peak swelling strains. Due to the potential alterations in the collagen-PG matrix during trypsin digestion, the correlation between the swelling strain and the shrinkage strain of the degenerated samples changed slightly in comparison with the normal samples. The proposed ultrasound method has been successfully used to measure the transient and inhomogeneous swelling behavior of the degenerated articular cartilage and has the potential for the characterization of osteoarthritis.

Lower risk of tuberculosis in obesity

BACKGROUND

Obesity is increasingly prevalent in both developed and developing areas. Although undernutrition is well associated with tuberculosis, few studies have systematically examined the association with obesity. Method A cohort of 42 116 individuals 65 years or older enrolled at 18 health centers for elderly patients in Hong Kong, China (which has a tuberculosis incidence of approximately 90 per 100,000 population), in 2000 were followed up prospectively through the territory-wide tuberculosis registry for the development of active tuberculosis from 3 months after enrollment until December 31, 2005, using the identity card number as the unique identifier. The association with body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters), as categorized by the Asian standards, was assessed with the control of other baseline characteristics.

RESULTS

Obese (BMI>or=30) and overweight (BMI, 25 to <30) individuals were at significantly lower risks of developing active tuberculosis than normal-weight individuals (BMI, 18.5 to <25), with hazard ratios (95% confidence intervals) of 0.36 (0.20-0.66) and 0.55 (0.44-0.70), respectively, after adjustment for baseline demographic, social, and clinical variables. An inverse linear association was observed predominantly for pulmonary but not extrapulmonary tuberculosis. This association persisted after controlling for potential confounders or excluding individuals with known tuberculosis risk factors.

CONCLUSIONS

Obesity is associated with a lower risk of active pulmonary tuberculosis in the older population of Hong Kong. The presence of such a strong but selective association across the whole spectrum of BMI could have major biological, clinical, and/or epidemiological implications. Further studies are indicated to explore the underlying mechanisms, potential clinical utilities, and possible epidemiological consequences.

Efficacy of tegaserod for functional constipation in Chinese subjects: a randomized double-blind controlled trial in a single centre

BACKGROUND

Tegaserod has been shown to be effective in chronic constipation in Western population. Aim We investigated if tegaserod is equally effective in Chinese population.

MATERIALS AND METHODS

Two hundred and fifty patients were randomized to a double-blinded 8-week treatment of tegaserod 6 mg b.d. or placebo. Response during weeks 1-4 was defined as an increase in complete spontaneous bowel motion >/=1/week. Secondary efficacy included response during weeks 1-8, individual symptoms and scores, quality of life and global assessment of bowel habits and constipation.

RESULTS

One hundred and nine patients from the treatment group and 107 from the placebo group completed the 8-week treatment. Responder rates was 47.7% vs. 29% for the treatment and placebo groups (P = 0.005). The sustained complete spontaneous bowel motion rate was 29.4% vs. 15.7% in the two groups (P = 0.016). The response rates were higher than that reported previously in the Caucasian studies. There was improvement in the scores for stool form scale, bothersomeness of constipation, abdominal distension/bloating and satisfaction of bowel habit (P < 0.05). The mental score was higher in the treatment group (46.8 +/- 9 vs. 43.6 +/- 10, P = 0.01).

CONCLUSIONS

Tegaserod is effective in relieving chronic constipation in Chinese population. The efficacy observed may be higher than that in Western population.

Non-attendance and effective equity of access at four public specialist outpatient centers in Hong Kong

This study tests whether socio-economic status (SES), at either the individual or ecologic levels, exerts a direct impact on non-attendance or an indirect impact on attendance through longer waiting time for appointments and/or doctor-shopping behavior at four public specialist outpatient centers in Hong Kong. We collected information through three main sources, namely patients' referral letters, telephone interviews with both open- and closed-ended questions (e.g. doctor-shopping data) and hospital administrative databases from a total of 6495 attenders and non-attenders enrolled from July 2000 through October 2001. Individual-level SES was measured by education, occupation and monthly household income. Tertiary planning unit (TPU)-level SES data consisted of proportion unemployed, proportion with tertiary education, median income and Gini coefficient. Direct effects of SES on non-attendance were examined by logistic regression. Indirect contributions mediated through waiting time and doctor-shopping were analyzed by structural equation modeling. We found that SES, at the individual or ecologic level, did not exert a direct effect on non-attendance. Instead, TPU-level SES contributed positively to waiting time (beta=0.06+/-0.03, p=0.048), i.e. worse-off neighborhoods (and those with greater income inequality) had a shorter waiting time. Individual-level SES was also directly associated with the likelihood of doctor-shopping (beta=0.16+/-0.02, p<0.001), i.e. the poor were less likely to doctor-shop. Both waiting time (beta=0.12+/-0.02, p<0.001) and doctor-shopping (beta=0.37+/-0.02, p<0.001) were significantly related to non-attendance. Our findings suggest a highly equitable specialist ambulatory care public system in Hong Kong. Health care resources are appropriately targeted at the socially indigent, and the poor are not discriminated against and pushed to seek alternative sources of care by the system. These results should be confirmed using a prospective design.

Sex hormone-induced mammary carcinogenesis in female Noble rats: detection of differentially expressed genes

Breast cancer is the most common cancer and the second most frequent cause of cancer death in women. Epidemiological data has recognized that an increased cumulative exposure to estrogen is the common tie linking most of the established risk factors for breast cancer. Sex hormone-induced mammary gland carcinogenesis of the Noble rat (using testosterone and 17beta-estradiol) resembles that of the human counterpart in its growth pattern as well as the histopathology of the tumors induced. This model may provide a paradigm for examination of genetic alterations and changes in gene expression between different histological groups and to make inferences about the role of known and putative oncogenes and tumor suppressor genes. We studied the gene expression profile during sex hormone-induced mammary carcinogenesis using a cDNA array technique; the results were further confirmed by RT-PCR, western blotting and immunohistochemical analyses. From the 10 differentially expressed genes identified, we have studied four highly overexpressed genes, two cell cycle/growth control regulators, the cyclins D1 and D2, a growth factor, IGF-2 and a cytokine TNF-alpha. Cyclins D1 and D2 were highly expressed in the nuclei of carcinoma cells but at low levels in the nuclei of the hyperplastic and normal mammary tissue. IGF-2 was found to expressed in the cytoplasm of the carcinoma cells but not in the stromal cells. Western blot showed expression of big IGF-2 consistent with the tumor derived truncated forms of pro-IGF-2. The matured circulating IGF-2 at 7.5 kDa identified in the serum was not expressed in any of the breast tissue samples. TNF-alpha expression was found not only in the macrophages but also in the mammary carcinoma cells. The result of the present study provides some information on the molecular basis of this sex hormone-induced mammary carcinogenesis and the role of these proteins in tumor progression.

No effect of a high-fat diet on promotion of sex hormone-induced prostate and mammary carcinogenesis in the Noble rat model

Results of international correlation and migrant studies suggest that dietary fat promotes carcinogenesis in hormone-sensitive sites, but this is disputed. In the present study, we used a Noble rat model of sex hormone-induced cancers to examine the effect of a high-fat diet on the incidence and latency of prostate and mammary cancer in male (n 139) and female (n 72) animals respectively. We also measured alpha-tocopherol levels in female breast tissue to determine whether a high intake of polyunsaturated fatty acids depletes antioxidant defence in target tissues, providing a possible potentiating mechanism for carcinogenesis. Results showed a very high incidence of hormone-induced adenocarcinomas of prostate and mammary gland, irrespective of diet. There was no difference in the pattern of carcinogenesis in different prostatic locations, weight of the prostate, or weight gain between male rats on the high-fat diet compared with the control (standard, low-fat) diet. In female rats, the incidence of mammary cancer and the body-weight gain were the same in both dietary groups, and breast alpha-tocopherol was also unaffected by dietary fat intake. Our present results are supportive of recent cohort studies that reported no significant association between intake of fat and the development of human prostate and breast cancer, and do not support a role for dietary fat in promoting sex hormone-induced prostate and mammary carcinogenesis.

The effect of flutamide and tamoxifen on sex hormone-induced mammary carcinogenesis and pituitary adenoma

We have established a female Noble rat model to explore the mechanisms of hormonal mammary carcinogenesis. Based on the previous finding that the dose of testosterone affects only the latency period of mammary cancer, not the final incidence and that androgen upregulates apoptotic activity in pre-malignant mammary glands, we hypothesised that estrogen is the initiator and androgen the promoter for hormonal mammary carcinogenesis of the rats. In the present study, rats were treated with the sex hormones together with flutamide and tamoxifen for both short term (7 and 13 weeks) and long term (12 months) durations. We showed that tamoxifen could totally inhibit mammary carcinogenesis while flutamide cause a delay and reduction in tumour incidence in the 12 months treatment term. Blocking effect of flutamide and tamoxifen on T + E2 (testosterone and 17beta-estradiol) short-terms treatment was demonstrated by the similar histological changes identified in the mammary glands of the T + E2 and drug treated rats to that of the age matched E2 and T controls, respectively. These findings give further support for the role of estrogen and androgen in mammary carcinogenesis. Autopsy of the tumour bearing rats showed presence of pituitary macroadenoma causing compression and atrophy of the brain stem. Immunohistochemical staining of these adenomas showed a predominance of prolactin-secreting cells. Serum assay also showed a corresponding increase in circulatory prolactin level. Tamoxifen was also effective in blocking the formation of pituitary adenoma in the sex hormone treated rats. Pituitary size and level of prolactin were higher in the T + E2 + flutamide group than the T + E2 group in both short-term and long-term treatments. It suggests that testosterone may have a role in counteracting estradiol stimulation on the pituitary lactotropes although it is synergistic to estrogen in mammary carcinogenesis. Pituitary adenomas were found in all rats that developed mammary adenocarcinoma but not vice versa suggesting that prolactin level elevation alone cannot lead to mammary tumorigenesis. The animal model, in addition to mammary carcinogenesis, may be useful for investigation of anti-estrogen therapy in pituitary adenomas.

Na+-H+ exchanger 3 (NHE3) is present in lipid rafts in the rabbit ileal brush border: a role for rafts in trafficking and rapid stimulation of NHE3

1. Rabbit ileal Na+-absorbing cell Na+-H+ exchanger 3 (NHE3) was shown to exist in three pools in the brush border (BB), including a population in lipid rafts. Approximately 50% of BB NHE3 was associated with Triton X-100-soluble fractions and the other approximately 50% with Triton X-100-insoluble fractions; approximately 33% of the detergent-insoluble NHE3 was present in cholesterol-enriched lipid microdomains (rafts). 2. The raft pool of NHE3 was involved in the stimulation of BB NHE3 activity with epidermal growth factor (EGF). Both EGF and clonidine treatments were associated with a rapid increase in the total amount of BB NHE3. This EGF- and clonidine-induced increase of BB NHE3 was associated with an increase in the raft pool of NHE3 and to a smaller extent with an increase in the total detergent-insoluble fraction, but there was no change in the detergent-soluble pool. In agreement with the rapid increase in the amount of NHE3 in the BB, EGF also caused a rapid stimulation of BB Na+-H+ exchange activity. 3. Disrupting rafts by removal of cholesterol with methyl-beta-cyclodextrin (MbetaCD) or destabilizing the actin cytoskeleton with cytochalasin D decreased the amount of NHE3 in early endosomes isolated by OptiPrep gradient fractionation. Specifically, NHE3 was shown to associate with endosomal vesicles immunoisolated by anti-EEA1 (early endosomal autoantigen 1) antibody-coated magnetic beads and the endosome-associated NHE3 was decreased by cytochalasin D and MbetaCD treatment. 4. We conclude that: (i) a pool of ileal BB NHE3 exists in lipid rafts; (ii) EGF and clonidine increase the amount of BB NHE3; (iii) lipid rafts and to a lesser extent, the cytoskeleton, but not the detergent-soluble NHE3 pool, are involved in the EGF- and clonidine-induced acute increase in amount of BB NHE3; (iv) lipid rafts and the actin cytoskeleton play important roles in the basal endocytosis of BB NHE3.

Spontaneous epidural haematoma associated with radiation-induced malignant fibrous histiocytoma

We report a case of spontaneous epidural haemorrhage associated with metastatic radiation-induced malignant fibrous histiocytoma of the dural meninges in a patient who had been previously treated for nasopharyngeal carcinoma with radiotherapy.

Chondromyxoid fibroma of skull base: a tumour prone to local recurrence

Chondromyxoid fibroma of the skull base is extremely uncommon. Sometimes involvement of the nasal cavity may occur and the patients may present with nasal symptoms. The biological behaviour of this tumour has not been well studied, primarily because of the limited number of reported cases and the short duration of follow-up. We report a histologically confirmed case of chondromyxoid fibroma of the skull base that recurred repeatedly over a 10-year period after the initial operation. Histologically it showed identical morphology to the original tumour with no evidence of histological progression or dedifferentiation. Ultrastructurally, the spindle tumour cells in the fibromyxoid area showed dual chondroblastic and fibroblastic differentiation, suggesting that these spindle fibroblastic cells and the better differentiated chondroid cells were of the same cell type with different histological morphology.

Blood supply of the knee joint. A microangiographic study in children and adults

The knee joint blood supply is derived from a rich anastomosis of the five major constant arteries, namely, the superior medial and lateral, the middle (posterior), and the inferior medial and lateral genicular arteries. Anastomosis also occurs with descending genicular arteries and the anterior tibial recurrent artery. These branches form anastomoses in and around the knee joint, while each major vessel was noted to provide the respective major blood supply to specific areas. The most obvious difference between vascularization of child and adult knees was the separation of vessels and relative avascularity of epiphyseal plate areas; such persisted until closure of the epiphyseal plate. The regions representing the seals of plate closure had less rich vascularization. A rich intraosseous blood supply was defined in the femoral and tibial condyles and the patella. Similarly, the adjacent and superficial soft tissues, including major ligaments and peripheral parts of the menisci, were richly vascularized. Areas of separated vascularization in children may have relevance to epiphyseal injury, growth deformity, Osgood-Schlatter disease, and hematogenous osteomyelitis. In adults, such information may be relevant to high tibial osteotomy, meniscus and cruciate ligament repair, and surgery utilizing the semitendinosus tendon, fascia lata, or patella tendon grafts.

The vascular and nerve supply of the human meniscus

Twenty-three fresh, cadaver knees were studied to evaluate details of the vascular and nerve supply of the menisci in humans. Vascularity was investigated using dye and latex injections, and the nerve supply was studied microscopically using a variety of special stains. Vessels arise mainly from medial and lateral inferior and middle geniculate arteries. Radial branches from a perimeniscal plexus enter the meniscus at intervals, with a richer supply to the anterior and posterior horns. Vessels supplying the body are limited to the peripheral one-third, except in the fetus. There is an avascular area adjacent to the popliteus tendon. The perimeniscal tissue is richly innervated. Most nerves are associated with vessels. Smaller nerves and axons run radially in convoluted patterns. Single axons course through the perimeniscal tissue, and many nerves are seen in the interstitial tissue of the outer one-third of the meniscus and in the anterior and posterior horns. The inner two-thirds has no nerve fibers.

The iliopsoas muscle pedicle bone graft: an experimental study of femoral head vascularity after subcapital fractures and hip dislocations

Distal iliopsoas muscle pedicle bone graft was investigated in dogs to determine whether a collateral blood supply to the femoral head can develop after displaced femoral neck fractures and dislocation of the hip joint. Microangiography performed in cadavers showed good vascularity of the muscle pedicle graft and similar studies in dogs showed that when transferred to the anterior femoral neck, the iliopsoas muscle pedicle graft healed with an ingrowth of vessels across the graft site. Microangiographic and histologic studies in dogs showed that the procedure could maintain the vascularity and viability of the grafted femoral head. Consequently, an iliopsoas muscle pedicle bone graft can provide a vascular supply to a compromised femoral head and may be applied in both the prevention and treatment of avascular necrosis of the injured femoral head.

Effect of the high femoral osteotomy upon the vascularity and blood supply of the hip joint

This investigation was done to study the effects of high femoral osteotomy upon the vascularity and blood supply of the hip and to further our knowledge of its physiologic basis. We have used established methods of study, including bone scans, microangiography, isotope clearance and perosseous venography, and based upon the results of these studies, we have reached certain conclusions. First, high femoral osteotomy increases the blood flow and vascularity in the hip joint, the femoral head and neck and the great trochanter. Second, bone scanning techniques using 99mTc labeled diphosphonate have shown increased uptake in the femoral head and neck after high femoral osteotomy. The localization was done using a Digital Gamma III computer, and the activity on the osteotomy side at two weeks was 3.5 times as great as on the control side. By 16 weeks postoperatively, there was still two times as much activity on the osteotomy side. Third, microangiography showed increased vascularity both at the osteotomy site and in the femoral head and neck and the greater trochanter on that side. Such an increase in vascularity first became evident two weeks after osteotomy and persisted during the four month period studied. Fourth, the results of the 99mTc diphosphonate clearance study showed a 25 per cent increase in femoral head blood flow on the operative side. Fifth, perosseous venography of the femoral head and neck showed a marked increase in venous drainage through the osteotomy site in the immediate postosteotomy stage.

Use and misuse of the MMPI in multiple sclerosis

A corrected profile for multiple-sclerosis-related symptoms was developed for the Minnesota Multiphasic Personality Inventory (MMPI). 64 multiple sclerosis (definite) patients' original and multiple sclerosis-corrected MMPI profiles were compared. Scale 1 (Hypochondriasis), Scale 3 (Hysteria), and Scale 8 (Schizophrenia) were significantly lowered when items relating to multiple-sclerosis symptomatology were deleted. The multiple sclerosis-corrected profile improved Shaw-Matthew's Pseudoneurological Scale's effectiveness in differentiating multiple sclerosis patients from pseudoneurotic patients. The need for symptom-correction scores for other neurological disorders is emphasized.

Circulatory and vascular changes in the hip following innominate osteotomy: an experimental study

The circulatory and vascular changes in the hip following Salter-type innominate osteotomy were studied in 35 dogs to determine the effects of innominate osteotomy on the blood supply of the hip joint. Microangiography, bone scanning, and isotope clearance were employed four months after the innominate osteotomy. Microangiography showed increased vascularity at the osteotomy site, in the ipsilateral side acetabulum, and in the femoral head in 65% of the dogs. Bone scanning with 99mTc diphosphonate showed increased activity at the osteotomy site, in the acetabulum, and in the femoral head and neck in 75% of the dogs. The 99mTc diphosphonate clearance studies showed that the blood supply to the femoral head was increased by almost 30% after innominate osteotomy in 50% of the dogs studied. These observations indicate that innominate osteotomy could increase the vascularity and blood supply of the hip by increasing the collateral circulation in the process of healing of the osteotomy. The physiologic basis of the joint to innominate osteotomy constitutes a rational basis for recommending the operation for the treatment of selected cases of congenital hip dislocation, Legg-Perthes disease of the femoral head, and degenerative osteoarthritis of the hip with or without acetabular dysplasia.