Isolation of leptin-binding peptides from a random peptide phage library

Leptin plays a role in regulating the body weight in mice. Injection of recombinant mouse leptin expressed in Escherichia coli reduced the food intake and body weight in normal, ob/ob and diet-induced obesity mice. Hyperglycemia, hyperinsulinemia and hypothermia can also be corrected in ob/ob mice after leptin injection. Leptin is a 16-kDa secretory protein comprising 167 amino acids produced in adipose tissue and is secreted to blood stream. In this study, a recombinant mouse leptin was generated and purified from a baculovirus expression system. This protein was used to identify putative ligands using a phage library of random peptides. Three leptin-binding phage clones were found, which were characterized by DNA sequencing and ELISA methods. The amino acid sequences of the reactive peptides are: LAYCSDPVRCLVWWY, MFWISAVSFVDHALV and LVLVLSAFLCCGVG. All three clones bound to recombinant human and mouse leptins. These peptides may be useful tools to study leptin-receptor interaction, food intake and body weight regulation.

Viral infections in children undergoing hematopoietic stem cell transplant

BACKGROUND

Although viral infection is a major clinical problem for hematopoietic stem cell transplant recipients, there are few large series reporting on these infections in the pediatric population. We performed a retrospective analysis of the impact of viral infections in this patient population in our center, managed by a uniform antiviral prophylaxis protocol.

METHOD

We reviewed the medical records of consecutive children and adolescents who received hematopoietic stem cell transplantation at the Division of Pediatrics, The University of Texas M. D. Anderson Cancer Center in Houston, TX, from July, 1992 to August, 1996.

RESULTS

During the study period there were 70 episodes of viral infections in 96 transplants. The viruses most commonly encountered were cytomegalovirus (24), varicella-zoster (21) and herpes simplex (10). Fifty of these episodes resulted in clinically apparent diseases, affecting 39 patients. The Kaplan-Meier estimated probability for the development of viral diseases was 62%. Ten percent of these patients died as a direct result of the infectious process, all within 4 months of transplant. Significant factors for development of viral disease were the development of acute graft-vs.-host disease and the duration of preengraftment neutropenia.

CONCLUSIONS

Viruses are common pathogens after hematopoietic stem cell transplantation in the pediatric population. Despite routine antiviral prophylaxis the morbidity and mortality of viral infections remain high. Enhancement of immune recovery after hematopoietic stem cell transplantation together with the development of new classes of antiviral agents may impact the incidence and prognosis of viral infections in this setting.

Insular and anaplastic carcinoma of the thyroid: a 45-year comparative study at a single institution and a review of the significance of p53 and p21

OBJECTIVE

To analyze the clinicopathologic features of a large cohort of patients with insular or anaplastic carcinomas treated at a single institution.

SUMMARY BACKGROUND DATA

Insular and anaplastic carcinomas of the thyroid, although uncommon, have more aggressive clinical behavior than well-differentiated carcinomas of the thyroid. In the literature, the incidence and features of these carcinomas have not been fully characterized.

METHODS

The authors reclassified 740 primary thyroid carcinomas diagnosed and treated between January 1, 1954, and December 30, 1998, to select those with features that met the histologic criteria of insular or anaplastic carcinoma. The clinicopathologic features of these carcinomas were studied and compared. The expression of p53 and p21 in these tumors was analyzed by immunohistochemistry.

RESULTS

Twenty-two patients (5 men, 17 women) with insular carcinoma and 38 patients (7 men, 31 women) with anaplastic carcinoma were found. Patients with insular carcinomas were younger (mean age 45 vs. 70 years) and had smaller tumors than those with anaplastic carcinomas (mean diameter 5 vs. 8 cm). Insular carcinomas were commonly mislabeled as other histologic subtypes, whereas anaplastic carcinomas might be overdiagnosed on pathologic examination. A history of longstanding goiter (>10 years) was noted in 27% of patients with insular carcinoma and 24% of patients with anaplastic carcinomas. Concomitant well-differentiated carcinomas of the thyroid were noted in 59% of patients with insular carcinoma and 39% of patients with anaplastic carcinoma. In anaplastic carcinomas, 13% of patients had concomitant insular carcinoma. Calcification or bone was noted in the stroma of 23% of patients with insular carcinomas and 47% of those with anaplastic carcinomas. The 10-year survival rates for patients with insular carcinoma and anaplastic carcinoma were 42% and 3%, respectively. Distant metastases were seen in 32% of patients with insular carcinoma and in 47% of patients with anaplastic carcinomas. In both types of carcinomas, metastatic tumors were often seen in bone and lung. Distant metastases were noted in a variety of organs in anaplastic carcinomas. In insular carcinoma, neither p53 nor p21 expression was present. In anaplastic carcinoma, p53 and p21 expression was identified in 69% and 3%, respectively. Concomitant expression of p53 and p21 was noted in one tumor.

CONCLUSIONS

Insular carcinoma and anaplastic carcinoma had distinctive clinicopathologic features, and recognition of these histologic variants is important for better management of these tumors in the future. p53 overexpression might have a role in dedifferentiation from insular carcinoma to anaplastic carcinoma.

Fever and neutropenia in pediatric hematopoietic stem cell transplant patients

The objective of this study was to identify patterns of fever and neutropenia in pediatric patients undergoing initial hospitalization for hematopoietic stem cell transplantation. A retrospective review of 75 HSCTs over a 4-year period at a single institution was performed, of which 68% were allogeneic and 32% were autologous. Stem cell sources included bone marrow (29%), PBSC (52%) and umbilical cord blood (16%). Fever occurred in 74 (98%) of the episodes. Unexplained fever (FUO) occurred in 43%. Bacteremia without an anatomic focus occurred in 29%, while CVC associated infections occurred in 17%. In 49% of transplants at least one blood culture was positive. The incidence of bacteremia was higher in allogeneic HSCTs (58%) than in autologous transplants (29%). Gram-positive bacteria accounted for 71% of the isolates. Lower rates of bacteremia were observed in patients receiving oral fluoroquinolone prophylaxis. The median duration of fever was 12.5 days and time to engraftment 14 days. Regression analysis demonstrated that duration of fever was strongly associated with time to engraftment, and that time to engraftment was associated with source of cells and number of CD34+ cells/kg administered. Recipients of autologous PBSC had the shortest durations of fever and time to engraftment, while recipients of allogeneic umbilical cord blood had the longest. Bone Marrow Transplantation (2000) 25, 59-65.

Acquired pseudocholinesterase deficiency after high-dose cyclophosphamide

Succinylcholine, a depolarizing neuromuscular blocking agent used in anesthesia is hydrolyzed in the plasma by the enzyme pseudocholinesterase (PSC). Conditions associated with reduced PSC activity lead to sustained action of succinylcholine and result in prolonged apnea. Cyclophosphamide is an inhibitor of PSC and its suppressive effect may be dose-dependent. We report a case of severe PSC deficiency after high-dose cyclophosphamide at 7 g/m2. The patient received succinylcholine during anesthesia 9 h after chemotherapy and developed prolonged apnea. This case highlights the potential risk of drug-induced PSC deficiency and cautions the use of depolarizing muscular relaxants soon after high-dose cyclophosphamide.

Amyloidosis complicating idiopathic myelofibrosis

An 84-year-old man presented with ankle edema, significant proteinuria, and mild impairment of renal function soon after treatment was started for idiopathic myelofibrosis. Renal amyloidosis was found on biopsy. The amyloid deposit was resistant to potassium permanganate treatment and showed no immunoreactivity to immunoglobulin light chains, beta-amyloid protein, or amyloid A component. A review of the literature showed that the occurrence of amyloidosis in idiopathic myelofibrosis is very rare, and the chemical nature of the amyloid involved remains unclear.

Acute renal failure after immersion in seawater polluted by diesel oil

Acute renal failure after exposure to toxic doses of hydrocarbon has been uniformly associated with multiorgan failure. We report a case of isolated acute renal failure in a patient after immersion in seawater polluted by diesel oil. The sites of absorption were likely to be skin, gastrointestinal tract, and lung. Investigations showed renal impairment as the only consequence from the exposure. The patient recovered uneventfully and did not require dialysis. This case highlighted the unusual consequence of isolated renal involvement resulting from hydrocarbon toxicity.

Cell block preparation on residual ThinPrep sample

The liquid-based cytology system ThinPrep has overcome many of the deficiencies of the conventional Pap test. However, the cytologic appearances of the cells in the liquid-based medium are different and staffs of laboratories adopting the new system have to be specially trained. Even after the training sessions provided by the vendor, the cytology staff still face a sharp learning curve initially. One way to recognize the different appearances of cells in the liquid-based system is to look at paired split-sample cases from the same patient in laboratories offering the test as an adjunct to the conventional Pap test. Laboratories offering direct-to-vial testing may be able to overcome the difficulties with some cases by performing cell block sections of residual materials in the samples. The protocol for making cell blocks and its application in resolving difficulties with high-grade squamous and glandular epithelial lesions is illustrated in this report. Diagn. Cytopathol. 1999; 21:427-431.

Peripheral neuropathy during alpha-interferon therapy in a child with Hodgkin's disease

Peripheral neuropathy is one of the rarely reported neurological complications of interferon therapy. The authors report such a case in a 15-year-old boy during alpha-interferon therapy for Hodgkin's disease. He received alpha-interferon at a dose of 1.8 million units/day 5 times a week by subcutaneous injections as adjuvant immunotherapy post autologous stem cell transplant. Twenty months after the initiation of therapy, he complained of severe pain in his lower distal extremities. Neurological examination revealed the absence of deep tendon reflexes. A nerve conduction study showed a sensorial, polyneuropathic involvement in the lower extremities. Within 4 weeks after the stopping of interferon, his pain improved, and recovery was also seen by nerve conduction studies. Symptoms reappeared at the resumption of interferon treatment. This study suggests that peripheral neuropathy may rarely occur in patients given long-term interferon treatment at high cumulative dosage.

Substance use disorders among adolescents in Taiwan: prevalence, sociodemographic correlates and psychiatric co-morbidity

BACKGROUND

This paper reports prevalences, sociodemographic correlates and psychiatric co-morbidity of substance use disorders (SUDs) among adolescents in Taiwan.

METHODS

A random sample of ninth grade students (N = 774) was selected from an urban, a suburban and a rural community. Two-stage case identification was employed with a brief screening tool and a modified Chinese version of the Kiddie-SADS conducted by child psychiatrists.

RESULTS

The overall prevalence of any SUD was 11.0%, with nicotine (96.0%) as the most prevalent substance. The prevalences of SUDs were significantly higher in boys, rural community and classes with poor academic performance. Sixty-two per cent of all SUD cases suffered from other concurrent psychiatric disorders. The most common co-morbid conditions were conduct disorder, attention deficit hyperactivity disorder and mood disorders.

CONCLUSIONS

High prevalences of SUDs were found among adolescent school children in Taiwan. Effects of urbanization, selective migration and the availability of substances are possible explanations for the urban-rural difference on the risk for SUDs. Psychiatric co-morbid conditions for SUD among adolescents in Taiwan were similar to those in Western societies.

Potential utility of MRI in the evaluation of children at risk of renal scarring

BACKGROUND

Gadolinium-enhanced MRI has recently been employed in the diagnosis of acute pyelonephritis. Its potential utility in the diagnosis of renal scars in children is unknown. Objective. To evaluate the potential utility of MRI using fat-saturated T1-weighted (T1-W) and post-gadolinium, short-tau inversion-recovery (STIR) sequences in detecting renal scarring by comparison with technetium dimercaptosuccinic acid ((99 m)Tc-DMSA) renal scintigraphy in children at risk of renal scarring.

MATERIALS AND METHODS

A group of 24 children with spina bifida and neurogenic bladder or anorectal anomaly was studied. No patient had a history of acute pyelonephritis. Documented urinary tract infection (UTI) was present in 10 children (42 %). The remaining 14 (58 %) children had a history of asymptomatic bacteriuria. None had clinical signs or symptoms of acute UTI at the time of the study. (99 m)Tc-DMSA and MRI were performed to detect renal scarring. (99 m)Tc-DMSA scans were supplemented with pinhole imaging. MRI of the kidneys employed a fat-saturated T1-W sequence and a post-gadolinium STIR sequence employing a short echo time.

RESULTS

Of the kidneys studied, 33 % (n = 16) had evidence of a renal parenchymal defect suggestive of scarring on (99 m)Tc-DMSA. The concordance in the detection of a scarred kidney by post-gadolinium STIR sequence and (99 m)Tc-DMSA is 94 %; that by fat-saturated T1-W sequence and (99 m)Tc-DMSA is 82 %; that by both sequences (positive result on either sequence) and (99 m)Tc-DMSA is 100 %. Using (99 m)Tc-DMSA as the gold standard, MRI had a sensitivity of 100 % and a specificity of 78 % in the diagnosis of a scarred kidney. The concordance in the detection of a scarred zone by post-gadolinium STIR sequence and (99 m)Tc-DMSA is 68 %; that by fat-saturated T1-W sequence and DMSA is 44 %; that by both sequences (positive result on either sequence) and (99 m)Tc-DMSA is 84 %. MRI had a sensitivity of 84 % and a specificity of 86 % in the diagnosis of a scarred zone, using (99 m)Tc-DMSA as the gold standard.

CONCLUSION

The detection rate for renal scarring on MRI using the fat-saturated T1-W and post-gadolinium STIR sequences is comparable to planar (99 m)Tc-DMSA. MRI is of potential utility in the evaluation of children at risk of renal scarring.

Focal segmental glomerulosclerosis and mesangial sclerosis associated with myeloproliferative disorders

The myeloproliferative disorders (MPDs) are clonal disorders of the hematopoietic stem cell and classified as polycythemia vera (PV), essential thrombocythemia (ET), or agnogenic myeloid metaplasia (AMM), depending on the main hematopoietic lineage involved. Primary renal parenchymal lesions are not commonly reported in these cases. We conducted a retrospective analysis of 138 consecutive patients with MPD to determine the frequency of renal parenchymal complications. Five patients (3.6%) (two PV, two ET, one AMM) were found to have focal segmental glomerulosclerosis (FSGS) and diffuse mesangial sclerosis, presenting as proteinuria in all the cases and progressing to chronic renal failure in two cases. A possible common risk factor was a high platelet count, because abnormal platelet activation in MPD has been shown to contribute to the development of glomerulosclerosis. The pathophysiologic basis of our observations and the implications in management of MPD patients remain to be studied.

Beta-blockade in heart failure: a comparison of carvedilol with metoprolol

OBJECTIVES

This study was performed to compare the long-term clinical efficacy of treatment with metoprolol versus carvedilol in patients with chronic heart failure.

BACKGROUND

Beta-adrenergic blockade is of proven value in chronic heart failure. Metoprolol, a selective beta-blocker, is widely used, but recent trials suggest carvedilol, a nonselective beta-blocker with alpha-1-receptor antagonist activity and antioxidant activities, is also effective. It is uncertain, however, if these additional properties of carvedilol provide further clinical benefit compared with metoprolol.

METHODS

In this randomized double-blind control trial, 51 patients with chronic heart failure and mean left ventricular (LV) ejection fraction of 26% +/- 1.8% were randomly assigned treatment with metoprolol 50 mg twice daily or carvedilol 25 mg twice daily in addition to standard therapy after a four-week dose titration period for a total of 12 weeks. Response was assessed by a quality of life questionnaire, New York Heart Association class, exercise capacity (6-min walk test), radionucleotide ventriculography for LV ejection fraction, two-dimensional echocardiography measurement of LV dimensions and diastolic filling and 24-h electrocardiograph monitoring to assess heart rate variability.

RESULTS

Both carvedilol and metoprolol produced highly significant improvement in symptoms (p < 0.001), exercise capacity (p < 0.05) and LV ejection fraction (p < 0.001), and there were no significant differences between the two drugs. Carvedilol had a significantly greater effect on sitting and standing blood pressure, LV end-diastolic dimension and normalized the mitral E wave deceleration time.

CONCLUSIONS

Both metoprolol and carvedilol were equally effective in improving symptoms, quality of life, exercise capacity and LV ejection fraction, although carvedilol lowers blood pressure more than metoprolol.

Molecular pathology and clinicopathologic features of penile tumors: with special reference to analyses of p21 and p53 expression and unusual histologic features

OBJECTIVES

To examine the histologic features of p21 in penile tumors and to determine the role of p21 and p53 in the pathogenesis of this group of tumors.

METHODS

The clinicopathologic features of 87 patients with penile tumors were studied. The expression of p53 and p21 proteins in 49 cases was investigated by immunohistochemistry.

RESULTS

Of the 87 tumors studied, 84 represented primary penile tumors (72 malignant and 12 benign) and 3 represented secondary tumors (2 from bladder, 1 from nasopharynx). The primary malignant penile tumors included 66 surface carcinomas with squamous differentiation (92%), 3 cases of Paget disease (4%), 1 case of Bowen disease (1%), and 2 penile urethral squamous cell carcinomas (3%). The former group was subdivided into squamous cell carcinoma (n = 50), verrucous carcinoma (n = 8), basaloid squamous cell carcinoma (n = 3), adenoid squamous cell carcinoma (n = 3), spindle cell carcinoma (n = 1), and adenosquamous carcinoma (n = 1). The benign tumors were squamous cell papillomas (n = 10) and fibromatoses (n = 2). Expression of p21 and p53 was noted in 40% and 89%, respectively, of the 47 patients with primary surface penile carcinoma with squamous differentiation. Positive p21 and p53 expression was also seen in 2 cases of Paget disease. Staining for p21 was often weak and was found in the suprabasal region of carcinomas with squamous differentiation, while p53 expression was seen in the basal region of squamous cell carcinomas. Preinvasive lesions also showed p21 and p53 expression. An inverse correlation between p53 and p21 expression (p53(+)/p21(-) or p53(-)/p21(+)) was noted in half of the squamous cell carcinomas, 4 of 5 verrucous carcinomas, 2 of 3 basaloid squamous cell carcinomas, and in 1 spindle cell carcinoma. The other cases did not show this correlation.

CONCLUSIONS

Penile tumors had different histologic variants and p21/p53 expression patterns. Expression of p21 did play a role in some tumors and could be dependent or independent of p53 expression.

Stress-induced phenocopy of C. elegans defines functional steps of sensory organ differentiation

The differentiation of male specific sensory rays in the nematode Caenorhabditis elegans is a complex process regulated by multiple genetic components. A novel approach with heat shock treatment was employed to show that multistep regulation is involved in this process. Intervention in this stepwise regulation resulted in phenocopy of specific gene mutations. The results suggest that differential gene function acting at a precise time frame is necessary to guide the normal differentiation of sensory rays.

Tacrolimus and minidose methotrexate for prevention of acute graft-versus-host disease after HLA-mismatched marrow or blood stem cell transplantation

Thirty adults with leukemia or lymphoma transplanted with marrow or blood stem cells from 1-antigen mismatched related donors received tacrolimus and minidose methotrexate to prevent acute graft-versus-host disease (GVHD). The group had a median age of 42 years (range 18-56 years). Twenty-seven patients had advanced disease, and 13 were resistant to conventional therapy. Tacrolimus was administered at 0.03 mg/kg/day i.v. by continuous infusion from day -2, converted to oral at four times the i.v. dose following engraftment, and continued to day 180 post-transplant. Methotrexate 5 mg/m2 was given i.v. on days 1, 3, 6 and 11. Mild nephrotoxicity was common before day 100; 69% of patients had a doubling of creatinine, 56% had a peak creatinine greater than 2 mg/dl, and two patients were dialyzed. Other toxicities prior to day 100 thought to be related to tacrolimus included hypertension (45%), hyperkalemia (17%), hyperglycemia (14%), seizures (13%), headache (3%) and hemolytic uremic syndrome (3%). Grades 2-4 GVHD occurred in 59% (95% CI, 38-70%), and grades 3-4 GVHD in 17% (95% CI, 1-32%). Overall survival at 1 year was 29% (95% CI, 12-45%). We conclude that tacrolimus and minidose methotrexate is active post-transplant immunosuppression for patients with 1-antigen mismatched donors.

Treatment of membranous lupus nephritis with nephrotic syndrome by sequential immunosuppression

The optimal therapy for pure membranous lupus nephritis (MLN) with nephrotic syndrome remains controversial. While the risk of progressive renal deterioration may be small, persistent heavy proteinuria leads to the complications of oedema, hypoalbuminaemia, hyperlipidaemia, hypercoagulability, and venous thrombosis. We examined prospectively the efficacy and tolerability of a sequential immunosuppressive regimen in a cohort of 20 patients with nephrotic syndrome due to pure MLN (WHO Class Va and Vb). Initial therapy comprised prednisolone (0.8 mg/kg/d p.o.) and cyclophosphamide (2-2. 5 mg/kg/d p.o.). Prednisolone dosage was gradually tapered to 10 mg/d at 6 months, when cyclophosphamide was replaced by azathioprine (2 mg/kg/d p.o.) as maintenance therapy. Within 12 months of therapy 11(55%) patients had complete remission (CR), 7(35%) patients achieved partial remission (PR) (proteinuria reduced from 6.2+/-4.0 to 2.0+/-1.7 g/24 h, P<0.01), and 2 patients failed to respond. Improvements in proteinuria and serum albumin level were observed after 3-6 months of treatment. Non-responders had lower baseline serum albumin compared to complete responders. Renal function remained stable during follow-up for 73.5+/-48.9 months. 8 patients had disease relapse at 47+/-15 months. Early complications (</=12 months) included herpes zoster (40%), minor respiratory or urinary tract infections (25%), mild leukopenia (15%), and transient amenorrhea (14.3%). 4 of the 20 patients developed pulmonary tuberculosis during follow-up, at 35+/-24 months after the diagnosis of MLN. 8 patients had hyperlipidaemia. Haemorrhagic cystitis, permanent amenorrhea, vascular complications, and mortality were not observed. We conclude that this sequential immunosuppressive regimen is effective in 90% of patients with MLN and heavy proteinuria. Prudent consideration of the benefits and potential side-effects is required to determine the optimal management for individual patients.

Clinical and pathological characteristics of patients with glomerular diseases at a university teaching hospital: 5-year prospective review

OBJECTIVE: To examine the prevalence of glomerular disease in Hong Kong. DESIGN: Prospective review. SETTING: University teaching hospital, Hong Kong. PATIENTS: All patients who presented with suspected glomerular disease from 1993 through 1997. MAIN OUTCOME MEASURES: Histopathological diagnosis from biopsy examination and clinical features of presentation. RESULTS: A total of 1629 consecutive percutaneous renal biopsies of native kidneys showed glomerular disease in 1413 cases. The most common clinical indication for renal biopsy was persistent proteinuria (n=735; 52.0%), while the most frequently found glomerular lesion was immunoglobulin A nephropathy (n=338; 23.9%). Minimal-change nephrotic syndrome (n=125; 8.8%) and immunoglobulin M nephropathy (n=11; 0.8%), were the most common glomerular diseases that presented with nephrotic syndrome. The male to female ratio for lupus nephritis was 1:14 (n=290), whereas for minimal-change nephrotic syndrome, the ratio was 1.8:1 (n=125). Immunoglobulin A nephropathy and membranous glomerulonephritis (n=117) affected approximately equal numbers of male and female patients. Familial fibrillary glomerulonephritis, a disease hitherto unknown in Hong Kong, was diagnosed in two siblings. CONCLUSION: Immunoglobulin A nephropathy was the most common glomerular disease in this survey and represents an important cause of end-stage renal failure in the Hong Kong population.

Evaluation of the ThinPrep Papanicolaou test in clinical practice: 6-month study of 16,541 cases with histological correlation in 220 cases

OBJECTIVE: To evaluate the liquid-based ThinPrep Papanicolaou test. DESIGN: Prospective comparison of the ThinPrep test with the conventional Papanicolaou test. SETTING: Cervical smear specimens sent to a private practice, Hong Kong. PATIENTS: A total of 16,541 ThinPrep test specimens and 7258 conventional Papanicolaou smears from Hong Kong women who had been screened for cervical cancer between mid-July 1998 and mid-January 1999. MAIN OUTCOME MEASURES: Specimen adequacy, endocervical cell content, epithelial cell abnormalities, and micro-organisms present in both types of cervical smears; histological diagnosis of cervical biopsy specimens of women who had the ThinPrep test. RESULTS: Compared with the conventional Papanicolaou smear test, the ThinPrep test showed a reduction in the frequency of 'unsatisfactory' (0.56% versus 1.36%; P<0.01), 'satisfactory but limited' (1.67% versus 15.87%; P<0.01), and 'atypical squamous cells of undetermined significance' reports (1.72% versus 3.64%; P<0.01). The ThinPrep test was also more effective at detecting squamous intraepithelial lesions, showing a 58% increase for low-grade lesions (2.66% versus 1.68%; P<0.01) and 28% increase for high-grade lesions (1.71% versus 1.34%; P<0.01). The sensitivity and positive predictive value of the ThinPrep system were 97.5% and 94.2%, respectively. The liquid-based method yielded a higher percentage of samples that contained endocervical cells compared with conventional smear specimens (70.57% versus 51.23%; P<0.001). CONCLUSIONS: The ThinPrep test has a high sensitivity and positive predictive value. The ThinPrep test gives higher-quality specimens and has a higher detection rate of squamous intraepithelial lesions than the conventional Papanicolaou smear test. The drawbacks of the liquid-based system, however, pertain to cost and the additional procedures and training needed.

Immortalization of human prostate epithelial cells by HPV 16 E6/E7 open reading frames

BACKGROUND

The exact pathogenesis for prostate cancer is not known. Progress made in prostate cancer research has been slow, largely due to the lack of suitable in vitro models. Here, we report our work on the immortalization of a human prostate epithelial cell line and show that it can be used as a model to study prostate tumorigenesis.

METHODS

Replication-defective retrovirus harboring the human papillomavirus (HPV) type 16 E6 and E7 open reading frames was used to infect primary human prostate epithelial cells. Polymerase chain reaction, followed by Southern hybridization for the HPV 16 E6/E7, Western blot for prostatic acid phosphatase, telomeric repeat amplification protocol assay for telomerase activity, two-dimensional gels for cytokeratins, and cytogenetic analysis were undertaken to characterized the infected cells.

RESULTS

The retrovirus-infected cell line, HPr-1, continued to grow in culture for more than 80 successive passages. Normal primary cells failed to proliferate after passage 6. HPr-1 cells bore close resemblance to normal primary prostate epithelial cells, both morphologically and biochemically. However, they possessed telomerase activity and proliferated indefinitely. Cytogenetic analysis of HPr-1 cells revealed a human male karyotype with clonal abnormalities and the appearance of multiple double minutes.

CONCLUSIONS

The HPr-1 cells expressed prostatic acid phosphatase and cytokeratins K8 and K18, proving that they were prostate epithelial cells. They were benign in nude mice tumor formation and soft agar colony formation assay. The HPr-1 cell line is an in vitro representation of early prostate neoplastic progression.

Outpatient treatment of fever and neutropenia for low risk pediatric cancer patients

BACKGROUND

Fever and neutropenia (F&N) is a common complication of cancer chemotherapy. It is conveniently managed by hospitalization and empiric administration of parenteral antibiotics. This study attempted to determine whether pediatric cancer patients with F&N identified as low risk for morbidity and mortality by clinical criteria at the time of presentation could be treated safely as outpatients.

METHODS

Seventy-three episodes of F&N in 41 patients were studied prospectively over 2 years. Eligibility criteria included age > or =2 years, reliable caretakers, and residence within 1 hour of the hospital. Exclusion criteria included hemodynamic instability, dehydration, severe mucositis, pneumonia, leukemia/lymphoma induction therapy, bone marrow transplantation, or other serious comorbidity. Patients were evaluated, received a single dose of intravenous ceftazidime, and were observed for 3-16 hours. They were randomized to receive either oral ciprofloxacin or intravenous ceftazidime as outpatients. Patients were seen daily until they had been afebrile for at least 48 hours and had a rising absolute phagocyte count of >500 cells/microL.

RESULTS

Sixty-three of 73 episodes (86%) were successfully managed on an outpatient basis. For 31 of 33 episodes in the ceftazidime arm, the patients remained outpatients, compared with 32 of 40 in the ciprofloxacin arm; this difference was not statistically significant. On average, patients remained febrile for 2.7 days and were treated for 4.7 days. Seventy-seven percent of episodes required no modification of initial antibiotic therapy. Of the 10 patients who were hospitalized, 4 had prolonged fever and 3 had emesis. Protracted neutropenia was associated with the need for hospitalization. There were no deaths, intensive care unit transfers, or serious complications.

CONCLUSIONS

Carefully selected low risk children with fever and neutropenia can be treated safely as outpatients. Close daily medical scrutiny is required.

Transient monosomy 7: a case series in children and review of the literature

BACKGROUND

Monosomy 7 and deletions of the long arm of chromosome 7 [del (7q)] are recurrent, nonrandom chromosomal abnormalities associated with both de novo and therapy-related myelodysplastic syndromes (MDS). The overall prognosis for children and adults with these chromosomal abnormalities is poor. In the current report, the authors present five children with MDS associated with monosomy 7/del(7q) who achieved spontaneous hematologic disease remission as well as a review of the literature.

METHODS

Five children with either de novo or treatment-related MDS who achieved spontaneous hematologic disease remission are presented. Relevant clinical, cytogenetic, and fluorescent in situ hybridization data are included.

RESULTS

All patients were boys. Three had de novo MDS whereas two others previously had received chemotherapy for another malignancy. Four patients achieved spontaneous and durable hematologic disease remission that was associated with cytogenetic disease remission in all three patients tested. The fifth patient developed a disease recurrence and died with evidence of clonal evolution after a long interval of hematologic and cytogenetic remission.

CONCLUSIONS

A subset of children who develop MDS associated with monosomy 7 or del(7q) achieve spontaneous hematologic and cytogenetic improvement. Although this appears to be uncommon, further data are needed to determine the percentage of patients who improve without therapy and to define clinical characteristics that may predict this clinical outcome. These findings suggest that monosomy 7/del(7q) is insufficient to produce full leukemic transformation.

Tacrolimus for prevention of graft-versus-host disease after mismatched unrelated donor cord blood transplantation

Ten children with hematologic malignancies or a storage disease underwent transplantation using cord blood cells from an unrelated donor mismatched for 1 (n = 7) or 2 (n = 3) HLA antigens. The median total nucleated cell dose was 4.0 (range, 2.2-7.1) x 10(7)/kg. GVHD prophylaxis consisted of tacrolimus dose-adjusted to maintain a whole blood level of 5-15 ng/ml with or without methotrexate 5 mg/m2 i.v. on days 1, 3, 6 and 11. Corticosteroids were not administered prophylactically. Median follow-up is 12 months (range, 5-28 months). One patient had autologous recovery and subsequently relapsed 153 days post transplant. For the remainder of the patients, the median time to an ANC >0.5 x 10(9)/l was 21 days (range, 19-38 days), and the median time to platelets >20 x 10(9)/l was 39 days (range, 21-97 days). The actuarial risk of grade 2 GVHD was 77% (95% CI, 49-100%), and no patient had grades 3-4 GVHD. Two patients developed chronic GVHD. The survival rate is 90% (95% CI, 81-100%). The combination of tacrolimus and minidose methotrexate is active for the prevention of severe but not moderate acute GVHD after mismatched unrelated donor cord blood transplantation.

The diagnostic value of fine-needle aspiration cytology in the assessment of thyroid nodules: a retrospective 5-year analysis

OBJECTIVE: To audit the diagnostic accuracy and value of fine-needle aspiration cytology in the assessment of thyroid nodules over a 5-year period. DESIGN: Retrospective study. SETTING: Private practice, Hong Kong. PATEINTS: The computerised records from cytological and histological examinations of all thyroid specimens submitted from 1993 through 1997 were studied; the 1236 aspirates came from 1033 women and 175 men (gender was not specified in 28 cases). MAIN OUTCOME MEASURES: Cytological reports were classified diagnostically, and histological and cytological correlations were determined. RESULTS: Of the 1236 aspirates, 113 (9.1%) were unsatisfactory; 1013 (82.0%), including cysts, were benign; and 110 (9.0%) were neoplastic or malignant. Histological follow-up was available for 149 cases; 13 were unsatisfactory for cytological diagnosis. Statistical analysis of the remaining 136 cases yielded the following results: sensitivity of fine-needle aspiration cytology, 56%; specificity, 90%; positive predictive value, 74%; negative predictive value, 80%; accuracy, 79%. These results were within the range of previously published values. The sensitivity was improved by combining clinical information: if nodules larger than 3-cm diameter were excised (despite a non-neoplastic aspiration cytology report), the sensitivity increased to 71% and the accuracy to 84%. CONCLUSION: Fine-needle aspiration cytology is an effective screening test to help evaluate whether surgery is required in the management of thyroid nodules. False-positive and false-negative rates can be minimised by taking clinical and imaging data into consideration.

Depuration of metals from soft tissues of oysters (Crassostrea gigas) transplanted from a contaminated site to clean sites

The present study aimed at studying the transplantation of oysters from a polluted site Lau Fau Shan (existing oyster culture zone) in Deep Bay to two clean sites mariculture zones at Yung Shue O and Kat O. The hydrological data, growth of oyster shell length, mortality and metal contents in whole soft tissue were monitored from February 1993 to February 1994. The high growth phase (increase in shell length) and gametogenesis (decrease in dry weight of whole soft tissue) were noted in winter (with low temperature and high salinity), and slow growth phase and spawning in summer (with high temperature and low salinity). Significant reductions (p<0.05) of Cd, Cr and Pb concentrations (dry wt basis) in soft tissue of transplanted oysters were observed at Kat O by 29, 55 and 29%, respectively, and at Yung Shue O by 34, 44 and 34%, respectively, with respect to the baseline values for the first batch of oysters and the concentrations in samples collected from Lau Fau Shan in the same months. Maximum reductions of total metal burden in whole soft tissue (microg per individual oyster) of the first oyster batch were found for Cd, Cr, Pb and Sb to be 62, 49, 60 and 25%, respectively, at Kat O, and to be 56, 47, 32 and 49%, respectively, at Yung Shue O. For the second batch of oysters transplanted to Yung Shue O in July 1993, significant reductions (p<0.05) of Cd concentration and total burden of Cd by 60 and 21%, respectively, were observed in February 1994. The high accumulated mortality and the significant (p<0.05) lower growth rate of the transplanted oysters illustrated that the best time for transplantation of oysters should be between the end of gametogenesis and the start of spawning (i.e. January and February), and the oysters should not be kept for longer than 3 months at the transplantation sites.

Allogeneic blood progenitor cell collection in normal donors after mobilization with filgrastim: the M.D. Anderson Cancer Center experience

BACKGROUND

Information on the safety and efficacy of allogeneic peripheral blood progenitor cell (PBPC) collection in filgrastim-mobilized normal donors is still limited.

STUDY DESIGN AND METHODS

The PBPC donor database from a 42-month period (12/94-5/98) was reviewed for apheresis and clinical data related to PBPC donation. Normal PBPC donors received filgrastim (6 microg/kg subcutaneously every 12 hours) for 3 to 4 days and subsequently underwent daily leukapheresis. The target collection was > or =4 x 10(6)CD34+ cells per kg of recipient's body weight.

RESULTS

A total of 350 donors were found to be evaluable. Their median age was 41 years (range, 4-79). Their median preapheresis white cell count was 42.8 x 10(9) per L (range, 18.3-91.6). Of these donors, 17 (5%) had inadequate peripheral venous access. Leukapheresis could not be completed because of apheresis-related adverse events in 2 donors (0.5%). Of the 324 donors evaluable for apheresis yield data, 221 (68%) reached the collection target with one leukapheresis. The median CD34+ cell dose collected (first leukapheresis) was 462 x 10(6) (range, 29-1463). The main adverse events related to filgrastim administration in donors evaluable for toxicity (n = 341) were bone pain (84%), headache (54%), fatigue (31%), and nausea (13%). These events were rated as moderate to severe (grade 2-3) by 171 (50%) of the donors. In 2 donors (0.5%), they prompted the discontinuation of filgrastim administration.

CONCLUSION

PBPC apheresis for allogeneic transplantation is safe and well tolerated. It allows the collection of an "acceptable" PBPC dose in most normal donors with one leukapheresis, with minimal need for invasive procedures.

Development of a rat head exposure system for simulating human exposure to RF fields from handheld wireless telephones

The aim of this project was to develop an animal exposure system for the biological effect studies of radio frequency fields from handheld wireless telephones, with energy deposition in animal brains comparable to those in humans. The finite-difference time-domain (FDTD) method was initially used to compute specific absorption rate (SAR) in an ellipsoidal rat model exposed with various size loop antennas at different distances from the model. A 3 x 1 cm rectangular loop produced acceptable SAR patterns. A numerical rat model based on CT images was developed by curve-fitting Hounsfield Units of CT image pixels to tissue dielectric properties and densities. To design a loop for operating at high power levels, energy coupling and impedance matching were optimized using capacitively coupled feed lines embedded in a Teflon rod. Sprague Dawley rats were exposed with the 3 x 1 cm loop antennas, tuned to 837 or 1957 MHz for thermographically determined SAR distributions. Point SARs in brains of restrained rats were also determined thermometrically using fiberoptic probes. Calculated and measured SAR patterns and results from the various exposure configurations are in general agreement. The FDTD computed average brain SAR and ratio of head to whole body absorption were 23.8 W/kg/W and 62% at 837 MHz, and 22.6 W/kg/W and 89% at 1957 MHz. The average brain to whole body SAR ratio was 20 to 1 for both frequencies. At 837 MHz, the maximum measured SAR in the restrained rat brains was 51 W/kg/W in the cerebellum and 40 W/kg/W at the top of the cerebrum. An exposure system operating at 837 MHz is ready for in vivo biological effect studies of radio frequency fields from portable cellular telephones. Two-tenths of a watt input power to the loop antenna will produce 10 W/kg maximum SAR, and an estimated 4.8 W/kg average brain SAR in a 300 g medium size rat.

Fine-needle aspiration cytology of mucocelelike tumors of the breast

Mucocelelike tumors of the breast encompass a spectrum of pathologic lesions, including benign tumor, atypical ductal hyperplasia, carcinoma in situ, and colloid carcinoma. Because the fine-needle aspiration (FNA) cytology of mucocelelike tumors covering this pathologic spectrum is not well defined, a study of 21 cases of mucocelelike tumors was conducted. Benign lesions are likely to be poorly cellular and to contain cohesive clusters of cytologically bland cells arranged in two dimensional sheets in the background of abundant mucoid material. Colloid carcinomas are usually highly cellular and contain loosely cohesive clusters and dissociated cells with nuclei showing minimal to mild atypia. The most discriminating feature between benign and malignant lesions appears to be the presence of many dissociated cells with intact cytoplasm. Cases with atypical ductal hyperplasia, with some bordering on carcinoma in situ as seen in 7 of the 12 benign cases, may be difficult to identify on FNA cytology, possibly because of sampling. As expected, some of the atypical cases have intermediate features of benign and malignant tumors. Because of overlapping features in borderline cases, we recommend excisional biopsy for all mucocelelike lesions. Myxoid fibroadenoma is more cellular than benign mucocelelike lesions and can be distinguished from carcinoma by the absence of dissociation and presence of numerous bare nuclei of bland morphology in the background. The mucoid material of myxoid fibroadenoma stained brightly pink rather than magenta as in mucocelelike tumors using the Diff Quik stain.

Economic and resource utilization analysis of outpatient management of fever and neutropenia in low-risk pediatric patients with cancer

PURPOSE

To measure resource allocation in outpatient management of fever and neutropenia in low-risk pediatric patients with cancer and its impact on their families.

PATIENTS AND METHODS

A prospective clinical trial was conducted. Eligible patients received a single dose of intravenous (IV) antibiotics and were observed for several hours in clinic. Patients were randomly assigned to continue either IV or oral antibiotics and were seen daily as outpatients. Charges were calculated based on the number of resources used and Medicare/Medicaid reimbursement schedules. A questionnaire was used to measure the impact of outpatient treatment on the family.

RESULTS

Seventy-three episodes of fever and neutropenia were studied. The median duration of treatment was 4 days. Eighty-six percent of the episodes were managed without hospitalization. The median calculated charge was $1840. The median calculated charge for patients receiving oral antibiotics was $1544 and was significantly less than the $2039 median charge for outpatients treated with IV antibiotics. The estimated charge for comparable inpatient treatment was $4503. Nearly all families preferred outpatient care, and few reported a loss of work hours or increased child care expenses.

CONCLUSIONS

Outpatient treatment of low-risk episodes of fever and neutropenia is substantially less costly than inpatient care and is preferred by most families.

Fludarabine-based preparative protocol for unrelated donor cord blood transplantation in children: successful engraftment with minimal toxicity

Unrelated umbilical cord blood (UCB) is a new source of hematopoietic stem cell (HSC) for allogeneic transplantation. The optimal conditioning for UCB transplant has not been defined. Intensive immunosuppression is frequently employed because of the higher risk of graft failure. Fludarabine monophosphate is shown to be an effective agent for facilitating allogeneic HSC engraftment. We have recently encountered three children who were not ideal candidates for 'conventional' conditioning protocols. TBI followed by fludarabine and melphalan were used for transplant preparation. The UCB units were one HLA-antigen (n = 1) and two HLA-antigen mismatched with the recipients. All three patients engrafted successfully. There was mild extramedullary toxicity. Two patients are alive with complete chimerism 8 and 20 months after transplant. A fludarabine-based protocol may be considered for selected cases of UCB transplants.

The natural history of dengue illness based on a study of hospitalised patients in Singapore

AIM OF STUDY

To study the clinical features of dengue illness in hospitalised patients in Singapore.

METHODS

One-hundred and thirty hospitalised patients with serologically confirmed dengue illness, from 1 April 1992 to 31 October 1992, were analysed retrospectively.

RESULTS

Teenagers and young adults between 15 to 30 years of age were most commonly affected. The male to female ratio was 1.3:1. The mean duration of fever and rash prior to admission were 5.2 +/- 1.5 (mean +/- SD) days and 1.7 +/- 1.7 days respectively. Petechiae were present in 52.3% of the patients. Three-quarters of the patients with petechiae had platelet counts (PCs) of 100 x 10(3) ul-1 or less. Thrombocytopenia (PCs of 100 x 10(3) ul-1 or less) was first documented 5.8 +/- 1.4 days after the onset of illness. The nadir of thrombocytopenia occurred on the 6.4 +/- 1.6 day of illness. The mean duration of thrombocytopenia was 3.6 +/- 1.6 days. Nineteen patients (14.6%) had non life-threatening clinical bleeding or coagulopathy, namely bleeding gums (9 patients), epistaxis (5), vaginal spotting/menorrhagia (4) and prolonged PTT (3). Six patients (4.6%) required platelet transfusion because of severe thrombocytopenia (PCs less than 30 x 10(3) ul-1) and clinical bleeding. There was no secondary fall in the PCs over 2 or more consecutive days when the PCs were in the recovery phase. It took 1 more day to reach PCs of 100 x 10(3) ul-1, the "safe" level commonly used in Singapore to decide discharge of patients, as compared to 80 x 10(3) ul-1. At PCs of 80 x 10(3) ul-1 or more, 2 patients had bleeding gums, 1 each had epistaxis and vaginal spotting. No transfusion was required for these 4 patients. The mean hospital stay was 4.2 +/- 1.5 days. There was no mortality in this study.

CONCLUSION

Dengue illness is a relatively benign self-limiting illness. When the PCs are on the rising trend and in the absence of clinical bleeding, it is reasonably safe to discharge patients when the PCs reach 80 x 10(3) ul-1, instead of 100 x 10(3) ul-1. This will shorten each patient's stay by 1 day, resulting in cost saving and more efficient use of hospital beds.

Desmoplastic malignant melanoma on the buttock of an 18-year-old girl: differentiation from desmoplastic nevus

Melanocytic proliferation in young people may sometimes pose a diagnostic dilemma. This is particularly so when a desmoplastic component is present. Because the two main differential diagnoses, desmoplastic malignant melanoma and desmoplastic Spitz nevus, share some morphologic features, the diagnosis of desmoplastic malignant melanoma may be overlooked. Distinction between the two is important because they show completely different biological behavior. The age of patient, site of lesion, histologic findings of melanocytic atypia, neurotropism, mitosis, and maturation help to distinguish the two entities. We report a case of desmoplastic malignant melanoma occurring in the buttock of an 18-year-old Chinese girl. Histologically, it had typical features of desmoplastic malignant melanoma with junctional melanocytic atypia and prominent neurotropism. Clinical and histologic differences between desmoplastic malignant melanoma and desmoplastic Spitz nevus are reviewed. We conclude that although desmoplastic Spitz nevus occurs much more commonly in adolescents, desmoplastic malignant melanoma can occur in this age group and even in non-sunexposed skin. Microscopic findings remain the mainstay that guides the final diagnosis.

Possible influences of ginseng on the pharmacokinetics and pharmacodynamics of warfarin in rats

We evaluated the significance of a reported clinical case of drug-drug interaction between ginseng and warfarin using a robust pharmacokinetic/pharmacodynamic approach in a rat model. The influence of ginseng on the pharmacokinetics and pharmacodynamics of oral warfarin after a single dose (2 mg kg(-1)) and at steady state (0.2 mg kg(-1) daily x 6 days) was studied in male Sprague-Dawley rats. Prothrombin time was employed as a pharmacodynamic index. Warfarin plasma concentration and vitamin K content in the ginseng extract were assessed by validated HPLC assays. The pharmacokinetics of warfarin after a single dose were not altered in the presence of ginseng; peak plasma concentration (control 7.8+/-0.5; ginseng 7.3+/-2.5 microg mL(-1)), time to peak (control 2.6+/-1.0; ginseng 3.1+/-1.1 h), elimination half-life (control 14.3+/-5.8; ginseng 10.6+/-3.1 h), and oral clearance (control 17.5+/-3.3; ginseng 20.2+/-5.5 mL h(-1)) were not significantly different (P>0.05). Similarly, alterations in the pharmacokinetics of warfarin were not detected under the multiple dosing paradigm. Under both dosing conditions, ginseng also showed no significant impact on the pharmacodynamics of warfarin as assessed by the area under the prothrombin time vs time curve (multiple dosing; control 3776+/-619, ginseng 3830+/-362 sh) and maximum prothrombin time (control 57.2+/-11.8, ginseng 63.3+/-9.1 s). Furthermore, the content of vitamin K was undetectable in the ginseng decoction. In conclusion, current data obtained in the rat showed no significant impact of ginseng on the pharmacokinetics/pharmacodynamics of warfarin when they are concomitantly administered.

Rapid drug metabolite profiling using fast liquid chromatography, automated multiple-stage mass spectrometry and receptor-binding

Rapid drug metabolite profiling can be achieved using fast chromatographic separation and fast mass spectrometric scanning without compromising the separation efficiency. Fast chromatographic separations of drug and its metabolites can be achieved by eluting from a short narrow-bore guard cartridge column (20 x 2 mm I.D., 3 microns BDS Hypersil C8) at flow-rate of 1.0 ml/min and with a gradient volume greater than 90 column volumes. The need for chromatographic separation is important for automated data dependent multiple-stage mass spectrometry (MSn) experimentation. The total analysis time of 8 min permits profiling of metabolites in a 96-well plate in 13 h. The narrow chromatographic peaks resulting from the high flow-rate require the use of a mass spectrometer capable of fast scan speed due to the need to perform multiple MS experiments within the same chromatographic analysis. A method has been developed for screening potentially biologically active in vitro microsomal metabolites by affinity binding with a receptor. After separation by centrifugal ultrafiltration, the bound ligands are released and characterized by LC-MS. In vitro microsomal metabolites of tamoxifen, raloxifene and adatanserin were screened for potential biological activity using this method. The in vitro metabolites of tamoxifen captured by the receptor include N-demethyltamoxifen and three species of hydroxytamoxifen; these data are consistent with those from a conventional binding study and bioassay. In addition, both hydroxyraloxifene and dihydroxyraloxifene are also recognized by the receptor. The specificity of the molecular recognition process is illustrated by the absence of binding with control microsomal incubate and with adatanserin and its metabolites. Therefore, active metabolites can be rapidly profiled by fast LC, automated MSn, and receptor binding. This information can be obtained quickly and can add value to the drug discovery process.

Long-term outcome of a phase II study of BM transplants, partially depleted ex-vivo of CD5-positive and CD8-positive T-lymphocytes in unrelated and related donor 1 antigen mismatched recipients

BACKGROUND

Mismatched family donor and unrelated donor BM transplants are associated with a high risk of acute GvHD. White T-cell depletion is the best method to reduce risk of acute GvHD, there was a reluctance to use T-cell depletion in the mismatched setting because of increased risk of rejection and relapse. Partial T-cell depletion, by the panning of CDS and CD8 positive T cells may reduce complications related to GvHD without compromising outcomes.

METHOD

In a long-term follow-up of a Phase II study of partial T-cell depletion by panning for BM transplant, 32 recipients received transplants from a single-Ag (HLA A, B, or DR) mismatched family donor; or an HLA serologically-matched unrelated donor. Patients were studied for engraftment, GHD, relapse and survival.

RESULTS

30 (94%) of the patients marrow engrafted. The cumulative risk of Grade 2-4 acute GvHD was 62 - 9%; of Grade 3-4 GvHD, 11 - 6%. The 4-year cumulative risk of relapse was 18 - 8% and actuarial survival was 44 - 9%.

DISCUSSION

Partial T-cell depletion had a low rate of severe acute GvHD without compromising engrafment or relapse risk.

The "hukou" system and rural-urban migration in China: processes and changes

Until recently, few people in mainland China would dispute the significance of the hukou (household registration) system in affecting their lives – indeed, in determining their fates. At the macro level, the centrality of this system has led some to argue that the industrialization strategy and the hukou system were the crucial organic parts of the Maoist model: the strategy could not have been implemented without the system. A number of China scholars in the West, notably Christiansen, Chan, Cheng and Seiden, Solinger, and Mallee, have begun in recent years to study this important subject in relation to population mobility and its social and economic ramifications. Unlike population registration systems in many other countries, the Chinese system was designed not merely to provide population statistics and identify personal status, but also directly to regulate population distribution and serve many other important objectives desired by the state. In fact, the hukou system is one of the major tools of social control employed by the state. Its functions go far beyond simply controlling population mobility.

Supermirror hard-x-ray telescope

The practical use of a grazing x-ray telescope is demonstrated for hard-x-ray imaging as hard as 40 keV by means of a depth-graded d-spacing multilayer, a so-called supermirror. Platinum-carbon multilayers of 26 layer pairs in three blocks with a different periodic length d of 3-5 nm were designed to enhance the reflectivity in the energy range from 24 to 36 keV at a grazing angle of 0.3 deg. The multilayers were deposited on thin-replica-foil mirrors by a magnetron dc sputtering system. The reflectivity was measured to be 25%-30% in this energy range; 20 mirror shells thus deposited were assembled into the tightly nested grazing-incidence telescope. The focused hard-x-ray image was observed with a newly developed position-sensitive CdZnTe solid-state detector. The angular resolution of this telescope was found to be 2.4 arc min in the half-power diameter.

Factors related to delayed treatment and posttreatment symptom severity in Taiwanese patients with benign prostatic hyperplasia

We evaluated the sociodemographic and clinical factors of delayed treatment and posttreatment symptom severity in outpatients with benign prostatic hyperplasia (BPH). The study included 146 BPH patients treated at the National Taiwan University Hospital in early 1997. All patients were treated with alpha-adrenergic antagonists or finasteride for at least 2 weeks. A questionnaire based on Andersen's Health Behavior Model was used to assess various sociodemographic features, while the pre- and posttreatment symptoms severity was rated according to the International Prostate Symptom Score (IPSS). Multiple logistic regression was used to assess the associations of these factors with delayed treatment and posttreatment symptom severity. Subjects who had recently quit smoking or were blue-collar workers tended to delay treatment, while those who chose a medical center as the care provider for chronic diseases tended to be less likely to delay treatment. However, none of these associations were statistically significant. No enabling factors (income, insurance) or need factors (symptom scores) evaluated were associated with delayed treatment. Predisposing factors associated with higher posttreatment symptom severity were delayed treatment (over 12 months) (adjusted odds ratio [OR]: 2.67, 95% confidence interval [CI]: 1.16-6.16), quitting smoking (adjusted OR: 4.47, 95% CI: 1.34-14.94), and having never smoked (adjusted OR: 3.73, 95% CI: 1.15-12.11). Subjects with severe pretreatment symptoms were far more likely than subjects with mild pretreatment symptoms to have severe symptoms after treatment (adjusted OR: 52.69, 95% CI: 54.46-621.90). Our findings, though based on a limited number of subjects, suggest sociodemographic factors rather than objective clinical attributes (prostate specific antigen level, prostate volume, and urodynamic results) are associated with delayed treatment in Taiwanese men with BPH. Both pretreatment symptom severity and sociodemographic factors are related to posttreatment symptom severity.

A sustainable behavioral intervention to increase condom use and reduce gonorrhea among sex workers in Singapore: 2-year follow-up

BACKGROUND

Prostitution is the most important source of transmission of AIDS and sexually transmitted diseases in Asia. We developed and evaluated the sustainability of an intervention to increase condom use and reduce gonorrhea among brothel-based sex workers in Singapore. The intervention focused on developing sex workers' negotiation skills, educating clients, and mobilizing support from peers and health staff in promoting condom use.

METHODS

A pretest-posttest design with one intervention site (n = 124) and another comparable control site (n = 122) was maintained for 5 months followed by a time series design to follow up the intervention group for 2 years.

RESULTS

At 5 months, the intervention group improved significantly in negotiation skills and were almost twice as likely as controls to always refuse unprotected sex (adjusted rate ratio 1.90, 95% CI 1.22-2.94). Gonorrhea incidence declined considerably by 77.1% in the intervention group compared with 37.6% in the controls. Consistent refusals of unprotected sex in the intervention group increased from 44.4% at baseline to 65.2% at 5 months, 73.6% at 1 year, and 90.5% at 2 years with a corresponding decline in gonorrhea.

CONCLUSION

Sustained condom use with a corresponding decline in gonorrhea was achieved by a behavioral and environmental intervention for sex workers.

Segmental small bowel allograft--ischemic injury and regeneration

PURPOSE

Small bowel transplantation (SBT) is the ultimate treatment for intestinal failure. It remains unclear as to which intestinal segment is more suitable for use in segmental SBT. The current study aims to assess the susceptibility of various parts of small intestine to ischemia and reperfusion injury and their capacity for regeneration.

METHODS

Thirty-two segments of pig jejunum and ileum were isolated with intact vascular pedicles that were clamped for periods varying from 1/2 to 8 hours. Biopsy specimens were taken immediately before clamp release and 20 minutes afterwards. All segments were anastomosed together before abdominal closure. Laparotomy was performed 24 hours later, and biopsy specimens were taken at all segments. All specimens were examined histologically by a pathologist.

RESULTS

Evidence of injury was detected after 1.5 hours of ischemia at jejunum, but only after 5 hours at ileum. More severe injury was noted at the initial period on reperfusion, but there was no further deterioration at the later period. Complete reepithelialization occurred after 24 hours even where there had been total villous sloughing at reperfusion, but regeneration was impossible when the crypts had been damaged completely.

CONCLUSIONS

Ileum, because it is more resistant to ischemia and reperfusion injury, may be preferred for segmental SBT. Regeneration of the bowel epithelium is fast, provided that the crypts are not damaged completely.

Fine needle aspiration of breast masses: an analysis of 1533 cases in private practice

The diagnostic efficacy of fine needle aspiration cytology of breast masses and the causes for unsatisfactory specimens in private practices were investigated in Hong Kong. All specimens that were submitted to the histopathology unit at the Canossa Hospital between 1 January 1996 and 30 April 1997 formed the basis of this report. A total of 1533 specimens were received from 1447 patients; 274 (17.8%) cases were unsatisfactory for assessment, 1080 (70.4%) were benign, 51 (3.3%) atypical, 19 (1.2%) suspicious, and 67 (4.4%) malignant. The specimens were submitted by 105 doctors, who each performed between 1 and 561 smears. The proportion of unsatisfactory samples was high for doctors who performed an occasional fine needle aspiration (48%; overall mean, 25%). Histological correlation was available in 165 cases. The overall sensitivity was 79%, specificity 98%, positive predictive value (including the 'suspicious' category) 92%, and negative predictive value 94%. Two false positive cases that were reported as suspicious were found to be fibroadenomata following subsequent excision biopsy. No adverse clinical outcomes were recorded for the false positive cases. There were six false negative cases (reported as a cyst in one case, benign in two cases, and atypical in three cases). The results compared favourably with published data and affirmed the effectiveness of the test in private practice.

Transfusion support using filtered unscreened blood products for cytomegalovirus-negative allogeneic marrow transplant recipients

It has been suggested that leukoreduced unscreened blood products can be used as an alternative to components from cytomegalovirus (CMV)-seronegative donors in order to prevent transmission of CMV from transfusions for CMV-seronegative marrow transplant recipients with CMV-seronegative donors, but confirmatory data are lacking. A retrospective chart review was undertaken for patients undergoing allogeneic transplantation over a 4-year period during which blood products were filtered for CMV-seronegative patients with CMV-seronegative donors when CMV-seronegative components were not available. Forty-five CMV-seronegative patient-donor pairs were identified. Only one patient developed CMV disease (pneumonia) and no other patients developed an infection. In this group of patients, the rate of CMV infection was 2.7% (95% CI, 0-8%) by life-table analysis. We conclude that filtered unscreened blood products as partial transfusion support for CMV-seronegative marrow transplant recipients were associated with a low incidence of CMV infection, justifying further evaluation of filtered blood products as total transfusion support for this patient population. However, since CMV infections still occur, continued surveillance by periodic culture or other techniques is warranted.

Allogeneic peripheral blood stem cell transplantation for active hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a lethal disorder of immune dysregulation. Successful allogeneic BMT is the only therapy that has produced long-term disease-free survival. However, for patients with active HLH the outcome of BMT remains poor when compared with those transplanted in remission. We describe a patient with active, recurrent HLH treated with high-dose chemotherapy and related allogeneic peripheral blood stem cell (PBSC) transplantation. Hematologic recovery was rapid and the post-transplant course was uncomplicated. The patient is alive and well 2 1/2 years after transplant. Allogeneic PBSC transplantation may deserve further evaluation as an alternative source of stem cells for transplantation in patients with active HLH.