Uterine artery embolisation for treatment of fibroids: experience in Chinese women

Twelve women with symptomatic fibroids were treated with transcatheter uterine artery embolisation with the use of polyvinyl alcohol (PVA) particles. For the nine women who were due for follow-up, reduction in uterine volume and dominant fibroid size were observed on magnetic resonance imaging. All the nine women had normal luteinising hormone (LH) and follicle stimulating hormone (FSH) levels before the procedure and during the follow-up. Seven of the nine women reported noticeable symptomatic improvement during the follow-up. Pain experienced was of variable level, but well controlled. Adequate analgesia is essential for the procedure. Longer follow-up and prospective fertility studies are required to evaluate the long-term effects before this procedure could be safely extended to younger age groups.

Recent advances in heme-protein sensors

In recent years, an increasing number of proteins have been discovered which utilize heme cofactors to sense oxygen, carbon monoxide and nitric oxide. The identification and characterization of these proteins are revising our understanding of heme-mediated allostery first established in the early 1960s. Biochemical and structural studies are revealing new mechanisms for heme-driven conformational changes distinct from the classical hemoglobin model.

Cardiac malformations associated with the congenital nephrotic syndrome

The association of cardiac malformation with the congenital nephrotic syndrome (CNS) has been previously reported in only one family. We report four patients with CNS: three with pulmonary valve stenosis (one requiring valvuloplasty) and one with discrete subaortic stenosis requiring surgical resection. We conclude that the cardiac status of all patients with CNS should be reviewed regularly by a paediatrician, with a low threshold for referral to a cardiologist, as flow murmurs due to chronic anaemia may obscure cardiac pathology. It is important to diagnose any associated cardiac lesions as these may require intervention, and may also predispose to the development of bacterial endocarditis if surgical or dental procedures are undertaken without appropriate antibiotic prophylaxis.

A randomized clinical trial comparing autologous blood clot and gelfoam in transarterial chemoembolization for inoperable hepatocellular carcinoma

BACKGROUND/AIM

Inoperable hepatocellular carcinoma is common in Asia and is usually treated with repeated transarterial chemoembolization. Gunji et al. showed better survival and fewer complications with autologous blood clot as compared with gelfoam used for embolization. Our aim was to compare the effect of blood clot versus gelfoam.

METHODS

We conducted a prospective randomized trial in 100 patients with inoperable hepatocellular carcinoma, and compared the side effects and cumulative survival in the two groups. Cox's proportional hazard model was used to study the prognostic factors.

RESULTS

The diameter of the main tumor was 7.9+/-4.6 cm. Our study did not show additional beneficial effects of blood clot. The proportion of side effects was similar and the common ones included fever, pain and vomiting. Though the hepatic artery remained patent for a longer period with blood clot (p=0.061), there was no difference in survival (p=0.129 for Okuda I disease and p=0.388 for Okuda II disease). Subgroup analysis showed longer survival in patients with vascular occlusion (p=0.034 for Okuda I and p=0.029 for Okuda II disease). The independent factors of survival were sex, Child's class, Okuda stage, tumor type and presence of metastases.

CONCLUSION

This study showed no additional benefits of blood clot in patients with inoperable hepatocellular carcinoma, in Okuda I and II disease. The longer survival in patients with vascular occlusion suggested that the damage to normal liver tissue by planned periodic transarterial chemoembolization may outweigh its benefit in later sessions of repeated TACE in certain patients.

Synthesis and characterization of the dimethyl-substituted bisbenzimidazole ligand and its manganese complex

Macrocycles with unique properties provide new avenues for the design of novel catalysts and materials. Here, we report, for the first time, the synthesis and characterization of the dimethyl-substituted bisbenzimidazole ligand (Me2BBZ) and its manganese complex (Mn-Me2BBZ). The Me2BBZ ligand is similar to porphyrin and phthalocyanine macrocycles in terms of its cavity size and metal-binding mode, but owing to electronic and charge differences, it exhibits properties that make it distinct from its structural counterparts. For instance, the optical spectra of bisbenzimidazoles lack transitions in the 500-900 nm region. Perhaps the most significant feature of the Me2BBZ ligand, however, is its inherent nonplanarity. Geometric restraints within this nonplanar ligand give rise to two atropisomers, which, when separated, could have potential in chiral catalysis and recognition. In addition, here we show that this nonplanarity can help to promote unusual crystal-packing interactions. Within the structure of the Mn-Me2BBZ complex, intermolecular pi-stacking interactions of the phenyl and benzimidazole groups lead to the formation of a distinct two-dimensional "staircase" lattice comprised of alternating Mn-Me2BBZ atropisomers. The potential significance of this structural arrangement is revealed by temperature-dependent magnetic studies that indicate weak antiferromagnetic coupling between the metal ions in the crystal. Fine-tuning of these long-range electronic and magnetic interactions could be useful for the design of novel molecular materials.

New mechanistic insights from structural studies of the oxygen-sensing domain of Bradyrhizobium japonicum FixL

The FixL heme domain serves as the dioxygen switch in the FixL/FixJ two-component system of Rhizobia. Recent structural studies of the Bradyrhizobium japonicum FixL heme domain (BjFixLH) have suggested an allosteric mechanism that is distinct from the classical hemoglobin model. To gain further insight into the FixL sensing mechanism, structures of BjFixLH bound to dioxygen, imidazole, and nitric oxide have been determined. These structures, particularly the structure of BjFixLH bound to its physiological ligand, dioxygen, have helped to address a number of important issues relevant to the BjFixLH sensing mechanism. On the basis of the oxy-BjFixLH structure, a conserved arginine is found to stabilize the dioxygen ligand in a mode reminiscent of the distal histidine in classical myoglobins and hemoglobins. The structure of BjFixLH bound to imidazole elucidates the structural requirements for accommodating sterically bulky ligands. Finally, the structure of BjFixLH bound to nitric oxide provides evidence for a structural intermediate in the heme-driven conformational change.

Structural trends in first-row transition-metal bis(benzimidazole) complexes

Dimethyl-substituted bis(benzimidazole) (Me2BBZ) is a novel macrocyclic ligand that possesses an intrinsic nonplanarity. To examine how metal-ion binding affects the magnitude of this nonplanarity, we have determined the structures of a periodic series of Me2BBZ complexes bound to Mn(II), Fe(II), Co(II), Ni(II), and Cu(II). These studies demonstrate that the extent of ligand ruffling and metal doming is indeed influenced by the nature of the metal. Concomitant with the periodic decrease of the ionic radii of the encapsulated divalent metal ion, a decrease in the magnitude of both the ligand nonplanarity and the metal out-of-the-plane distance is observed. For the metal out-of-the-plane distance, this correlation persists until the metal finally moves into the mean ligand plane. For the nonplanar distortion, the extent of the nonplanarity decreases to a limiting value that is intrinsic to the Me2BBZ ligand due to steric factors. These observations indicate that the relative sizes of the metal ion and the Me2BBZ ligand cavity have profound effects on the structural features of the metal-ligand complex.

Percutaneous ethanol injection as a possible curative treatment for malignant portal vein thrombosis in hepatocellular carcinoma

Postoperative residual hepatocellular carcinoma (HCC) with malignant portal vein thrombosis in a 48-year-old man was cured with transarterial chemoembolization (TACE) for the parenchymal portion and percutaneous ethanol injection (PEI) for the malignant portal vein thrombosis. No evidence of tumor recurrence was noted after 18 months of follow-up. The only severe complication in our patient was biliary stricture which was treated with an internal stent via endoscopic retrograde pancreatico-cholangiography (ERCP).

Structural basis for the design of antibiotics targeting peptide deformylase

While protein synthesis in bacteria begins with a formylated methionine, the formyl group of the nascent polypeptide is removed by peptide deformylase. Since eukaryotic protein synthesis does not involve formylation and deformylation at the N-terminus, there has been increasing interest in peptide deformylase as a potential target for antibacterial chemotherapy. Toward this end and to aid in the design of effective antibiotics targeting peptide deformylase, the structures of the protein-inhibitor complexes of both the cobalt and the zinc containing Escherichia coli peptide deformylase bound to the transition-state analogue, (S)-2-O-(H-phosphonoxy)-L-caproyl-L-leucyl-p-nitroanilide (PCLNA), have been determined. The proteins for both deformylase-inhibitor complexes show basically the same fold as for the native enzyme. The PCLNA inhibitor adopts an extended conformation and fits nicely into a hydrophobic cavity located near the metal site. On the basis of these structures, guidelines for the design of high-affinity deformylase inhibitors are suggested. As our results show that the protein residues which interact with the PCLNA inhibitor are conserved over a wide variety of species, we suggest that antibiotics targeting deformylase could have wide applicability.

Structure of a biological oxygen sensor: a new mechanism for heme-driven signal transduction

The FixL proteins are biological oxygen sensors that restrict the expression of specific genes to hypoxic conditions. FixL's oxygen-detecting domain is a heme binding region that controls the activity of an attached histidine kinase. The FixL switch is regulated by binding of oxygen and other strong-field ligands. In the absence of bound ligand, the heme domain permits kinase activity. In the presence of bound ligand, this domain turns off kinase activity. Comparison of the structures of two forms of the Bradyrhizobium japonicum FixL heme domain, one in the "on" state without bound ligand and one in the "off" state with bound cyanide, reveals a mechanism of regulation by a heme that is distinct from the classical hemoglobin models. The close structural resemblance of the FixL heme domain to the photoactive yellow protein confirms the existence of a PAS structural motif but reveals the presence of an alternative regulatory gateway.

The health consequences of vertebral deformity in elderly Chinese men and women

The following health consequences of vertebral deformity in Hong Kong elderly Chinese men and women were studied: the prevalence of back pain, disability due to back pain, and low morale. Lateral X-ray films were taken of the thoracic and lumbar spine of 796 community-dwelling Chinese subjects (396 men, 400 women) (aged 70-79). Subjects with one or more definitely deformed vertebra (reduction in vertebral height 3 SD or more below the mean) were classified as definite cases, those with one or more mildly deformed vertebra (reduction in vertebral height 2-2.99 SD below the mean) as mild cases, and the rest as controls. The prevalence and consequences of back pain were measured by a standardized questionnaire, and morale was measured by the Geriatric Morale Score. The relative risk (RR) and 95% confidence interval (CI) of having back pain and being depressed were calculated by logistic regression. Classifications included 16% of men and 30% of women as definite cases, 37% of men and 35% of women as mild cases, and 47% of men and 35% of women as controls. The relative risk (RR) of back pain was 2.3 (95% CI 1.4-3.9) (P < 0.05) in women with definite deformity and 1.5 (95% CI 0.9-2.5) (P > 0.05) in women with mild deformity, as compared with controls. Sixty-four percent of all men had back pain. This prevalence was much higher than figures obtained in a previous survey on low back pain. The prevalence of back pain did not differ by deformity status, but more men with vertebral deformity were on analgesic. There was no significant association between disability due to back pain and vertebral deformity in women. The RR for having a low morale score (of 5 and below) was 2.3 (95% CI 1.3-4.1) (P < 0. 05) in women with mild deformity; men with vertebral deformity did not have a low morale. It was concluded that vertebral deformity was associated with significant back pain and psychological morbidity in elderly Chinese women. Although men with vertebral deformity did not report more back pain, more were on analgesics than controls.

Expression of p16INK4 and retinoblastoma protein Rb in vulvar lesions of Chinese women

The protein products of the two tumor suppressor genes located on 9p and 13p, p16INK4 and Rb, respectively, play an important role in regulation of the cell cycle and are implicated in tumorigenesis. We examined 49 cases of benign vulvar lesions, vulvar intraepithelial neoplasia (VIN), and squamous cell carcinoma with immunohistochemical staining to determine expression of p16INK4 and Rb. All and 86% of benign lesions expressed Rb and p16INK4, respectively; 40% each of VIN I and VIN III expressed p16INK4 and Rb, respectively; and 37 and 68% of squamous cell carcinomas expressed p16INK4 and Rb, respectively. The combination of the lack of p16INK4 and/or Rb expression increased from benign lesions (14.3%), through VIN I (60%) and VIN III (60%), to invasive squamous cell carcinoma (72%), thus supporting the postulation that alterations in p16INK4 or Rb could be significant events in progression of disease. The loss of Rb expression also increased from stage I carcinoma (16.7%) through stage II (26.7%) and III (44.4%), to IV (50%), suggesting that Rb may play an important role in tumor progression. A larger study on VIN lesions and genetic coding is suggested to further investigate the role of p16INK4, Rb, and other factors in tumorigenesis and progression of vulvar cancers.

Crystal structure of the Escherichia coli peptide deformylase

Protein synthesis in bacteria involves the formylation and deformylation of the N-terminal methionine. As eukaryotic organisms differ in their protein biosynthetic mechanisms, peptide deformylase, the bacterial enzyme responsible for deformylation, represents a potential target for antibiotic studies. Here we report the crystallization and 2.9 A X-ray structure solution of the zinc containing Escherichia coli peptide deformylase. While the primary sequence, tertiary structure, and use of coordinated cysteine suggest that E. coli deformylase belongs to a new subfamily of metalloproteases, the environment around the metal appears to have strong geometric similarity to the active sites of the thermolysin family. This suggests a possible similarity in their hydrolytic mechanisms. Another important issue is the origin of the enzyme's specificity for N-formylated over N-acetylated substrates. Based on the structure, the specificity appears to result from hydrogen-bonding interactions which orient the substrate for cleavage, and steric factors which physically limit the size of the N-terminal carbonyl group.

Middle aortic syndrome in a boy with arteriohepatic dysplasia (Alagille syndrome)

Middle aortic syndrome is increasingly recognized as a cause of hypertension in adolescents and young adults. Alagille syndrome is a genetic disorder characterized by hepatic, eye, and bony abnormalities. Cardiovascular lesions occur in most of the patients, but narrowing of the abdominal aorta has not been previously recorded. We present an unusual association between middle aortic syndrome and Alagille syndrome, with a similar vascular lesion seen in two generations.

Human papillomavirus infection in Hong Kong Chinese women with normal and abnormal cervix--detection by polymerase chain reaction method on cervical scrapes

Detection of human papillomavirus (HPV) was accomplished by utilizing polymerase chain reaction methods on cervical scrapes from a total of 488 Hong Kong Chinese women attending the colposcopy, general, and antenatal clinics. From colposcopy clinic, 10% of normal cervix, 31% of condyloma, 56, 50, and 57% of CIN I, CIN II, and CIN III, respectively, and 88% of squamous cell carcinoma contain HPV. The overall detection rate is 30%. The most prevalent type is 16. Four percent of scrapes from normal cervix of patients attending general gynecology clinic and none from antenatal clinic show HPV. The detection rate appears to be more related to the types of cervical lesions than to the age of the patients.

Ovarian epithelial tumour in gonadal dysgenesis. A case report and literature review

A patient with gonadal dysgenesis was found to have a mucinous epithelial ovarian tumour on the left side and a streak gonad on the right. The preponderance of mucinous tumours (5 of 8) over other epithelial tumours in these patients is noted but the significance is not fully understood. Two models of pathogenesis (incessant ovulation and hypergonadotrophic hypogonadism) were proposed but neither satisfactorily explains the development of the tumours. Further ultrastructural, chromosomal and molecular biological study of these tumours may help to elucidate the underlying cause and pathogenesis.

Molecular characterization of the genes encoding the tungsten-containing aldehyde ferredoxin oxidoreductase from Pyrococcus furiosus and formaldehyde ferredoxin oxidoreductase from Thermococcus litoralis

The hyperthermophilic archaea Pyrococcus furiosus and Thermococcus litoralis contain the tungstoenzymes aldehyde ferredoxin oxidoreductase, a homodimer, and formaldehyde ferredoxin oxidoreductase, a homotetramer. herein we report the cloning and sequencing of the P. furiosus gene aor (605 residues; M(r), 66,630) and the T. litoralis gene for (621 residues; M(r), 68,941).

Structure of a hyperthermophilic tungstopterin enzyme, aldehyde ferredoxin oxidoreductase

The crystal structure of the tungsten-containing aldehyde ferredoxin oxidoreductase (AOR) from Pyrococcus furiosus, a hyperthermophilic archaeon (formerly archaebacterium) that grows optimally at 100 degrees C, has been determined at 2.3 angstrom resolution by means of multiple isomorphous replacement and multiple crystal form averaging. AOR consists of two identical subunits, each containing an Fe4S4 cluster and a molybdopterin-based tungsten cofactor that is analogous to the molybdenum cofactor found in a large class of oxotransferases. Whereas the general features of the tungsten coordination in this cofactor were consistent with a previously proposed structure, each AOR subunit unexpectedly contained two molybdopterin molecules that coordinate a tungsten by a total of four sulfur ligands, and the pterin system was modified by an intramolecular cyclization that generated a three-ringed structure. In comparison to other proteins, the hyperthermophilic enzyme AOR has a relatively small solvent-exposed surface area, and a relatively large number of both ion pairs and buried atoms. These properties may contribute to the extreme thermostability of this enzyme.

Cytomegalovirus infections in renal transplant patients

The incidence of cytomegalovirus infection in Chinese patients was reviewed in a retrospective study of 99 renal transplant recipients. CMV infection occurred in 18 patients (18.2%). In 4 the infection was considered primary and in 14 it was thought to be reactivation. Of the infections 88.9% occurred within the first 6 months after transplantation, 44.4% were asymptomatic, while the rest had protean manifestations with the commonest combinations of fever, hepatic dysfunction and haematological abnormalities. One patient succumbed to the infection. Significant difference was seen in the incidence of CMV infections among patients who had received different antirejection therapy, being the highest (37%) among those who had received either Atgam or OKT3. Among the various secretions, urine gave the best yield of virus cultures.

A blood pressure profile of rural Kadazans and Bajaus in Sabah, east Malaysia

A survey was conducted to document the blood pressures of two indigenous groups (Kadazans and Bajaus) who reside in rural Sabah in East Malaysia. Their health knowledge status is also recorded. Fifty percent of those surveyed were unable to associate high blood pressure with a risk factor and as high as 38% were unaware of the consequences of high blood pressure. A total of 16.2% had blood pressures > or = 140/or 90mm Hg while 3.9% had blood pressures > or = 160/or 95mm Hg. While these figures are low compared to those of developed countries, lifestyle changes associated with rapid urbanization in Malaysia may be expected to increase hypertension prevalence. The strengthening of health education programs is timely as health knowledge is limited and many hypertensives default treatment.

Nutritional status of Kadazan children in a rural district in Sabah, Malaysia

The nutritional status of 896 Kadazan children below 6 years of age from 23 villages of Tambunan District were studied. When stunting and wasting were defined as those who were below two standard deviations of height-for-age and weight-for-height (Waterlow et al, 1977) and based on the National Center for Health Statistics reference population, 67.6% of boys and 66.8% of girls were stunted while 12.3% of boys and 8.3% of girls were wasted. Weaning foods and toddler feeding practices were unsatisfactory. The role of health education on child care and feeding practices is emphasized.

The nitrogenase FeMo-cofactor and P-cluster pair: 2.2 A resolution structures

Structures recently proposed for the FeMo-cofactor and P-cluster pair of the nitrogenase molybdenum-iron (MoFe)-protein from Azotobacter vinelandii have been crystallographically verified at 2.2 angstrom resolution. Significantly, no hexacoordinate sulfur atoms are observed in either type of metal center. Consequently, the six bridged iron atoms in the FeMo-cofactor are trigonally coordinated by nonprotein ligands, although there may be some iron-iron bonding interactions that could provide a fourth coordination interaction for these sites. Two of the cluster sulfurs in the P-cluster pair are very close together (approximately 2.1 angstroms), indicating that they form a disulfide bond. These findings indicate that a cavity exists in the interior of the FeMo-cofactor that could be involved in substrate binding and suggest that redox reactions at the P-cluster pair may be linked to transitions of two cluster-bound sulfurs between disulfide and sulfide oxidation states.

Cytodiagnosis of lesions presenting as salivary gland swellings: a report of seven cases

The cytologic and histologic findings of seven cases presenting clinically as salivary gland swellings are described. These included two cases of pilomatrixoma of skin in the parotid region, two cases of neurilemmoma in the submandibular area, a case of Kimura's disease in the peri-mandibular gland lymphoid tissue, a case of Castleman's disease in intraparotid lymph node, and a case of branchial cleft cyst in the parotid region. It is important to recognize lesions that masquerade as salivary gland tumors so that misdiagnosis and overdiagnosis on smears can be avoided and the patients can be treated appropriately.

Genetic lesion in the carcinogenesis of cervical cancer

Allelic loss at specific chromosomal loci was demonstrated in carcinoma of the cervix (CaCx) obtained from Hong Kong Chinese by restriction fragment length polymorphism analysis. Altogether 12 patients with CaCx, 7 with cervical intraepithelial neoplasia (CIN) and 7 with normal cervical tissues were studied. Polymorphic DNA markers for chromosome 3 were used and the tumour and constitutional genotypes of the above patients were compared. Loss of heterozygosity (LOH) was found in 10 out of 12 informative cases with CaCx at RAF-1 locus (3p25) and in 10 out of 11 cases at D3S3 (3p14). Further study on patients with cervical intraepithelial neoplasia showed LOH at both 3p25 and 3p14 in four out of five cases. In normal cervical tissues, no LOH was demonstrated at both loci. Our data suggest that the deletion events occurring on the short arm of chromosome 3 at 3p25 and 3p14 are early events in the development of carcinoma of cervix. Since recessive genes have been reported to reside within or close to these 2 loci, important genes may have been lost or inactivated in the genesis of this tumour. Moreover, human papillomavirus (HPV) type 16, 18 or 33 was found in 8/12 of the carcinomas and 4/7 of CIN using Polymerase Chain Reaction and/or Southern Blot hybridization, confirming the close association with human papillomavirus. Whether the observed genetic lesions in the short arm of chromosome 3 in cervical "premalignant" and malignant lesions and their consistent association with high risk HPV represent independent events in the development of carcinoma of cervix will be discussed.

Cytodiagnosis of 112 salivary gland lesions. Correlation with histologic and frozen section diagnosis

Aspirates of 112 cases of salivary gland lesions with histologic correlation were reviewed. Fifty-five cases (49%) had frozen sections made. The 112 cases included 76 cases of benign lesions (31 cases of pleomorphic adenoma, 19 of Warthin's tumor and 26 of nonneoplastic lesions), 22 of primary salivary gland malignancy and 14 of metastatic malignant lesions. The overall accuracy in diagnosing benign and malignant lesions was 95%. The accuracy in diagnosing the exact category of neoplastic lesions was 70%. The diagnostic sensitivity for malignant lesions was 86% and the specificity, 99%. There was one false positive, in which a pleomorphic adenoma was diagnosed as small cell carcinoma. Five false-negative cases were encountered that were due to underdiagnosis of mucoepidermoid carcinoma and adenoid cystic carcinoma. The smears were reviewed, and the diagnostic pitfalls are discussed. A comparison of the cytodiagnosis and frozen section diagnosis was made. In frozen sections there were two false negatives, and two diagnoses were deferred. The overall diagnostic accuracy was 91%. The accuracy in diagnosing the exact category of neoplastic disease was 77%. The diagnostic sensitivity for malignant disease was 70% and specificity, 100%. Frozen section, however, did supplement the fine needle aspiration diagnosis in 13 cases.

The impact of donor and recipient hepatitis B surface antigen status on liver disease and survival in renal transplant recipients

Ninety-eight renal transplant recipients who had been followed for 1-6.5 years (median 3.2 years) were reviewed to determine the effect of donor and recipient hepatitis B surface antigen status on the incidence of hepatitis and on patient survival. The cumulative risk of developing hepatitis posttransplant was significantly higher in hepatitis B surface antigen-positive versus hepatitis B surface antigen-negative patients (P = 0.001). Nine (60%) of 15 patients who were hepatitis B surface antigen-positive prior to transplantation, 3 (75%) of 4 patients who became hepatitis B surface antigen-positive after transplantation, and 17 (22%) of 79 patients who were persistently hepatitis B surface antigen-negative developed hepatitis posttransplant. Five hepatitis B surface antigen-negative patients received allografts from hepatitis B surface antigen-positive donors. None of the five, including one who was initially seronegative, became hepatitis B surface antigen-positive posttransplant. Of the four patients who became HBsAg-positive posttransplant, three received kidneys from donors of unknown HBsAg status in China, while one was transplanted with a kidney from a HBsAg-negative donor. In summary, we found that the risk of developing hepatitis after renal transplantation was significantly higher in hepatitis B surface antigen-positive patients. However, both patient and graft survival were similar in hepatitis B surface antigen-positive and hepatitis B surface antigen-negative patients. The transplantation of kidneys from HBsAg-positive donors to HBsAg-negative patients did not result in clinically significant hepatitis or chronic HBsAg carriage. De novo hepatitis B infection may arise from sources other than the kidney itself.

Amino-aciduria and enzymuria in patients with artificial heart valves

Fifteen patients with artificial heart valves and evidence of chronic intravascular haemolysis were studied for proximal tubular dysfunction. Three patients had haemosiderinuria and haemoglobinuria; 2 had haemoglobinuria alone. Increased urinary amino acid nitrogen occurred in 8, raised fractional beta 2-microglobulin excretion in 2, hypophosphataemia in 4, renal glycosuria in 1 and enhanced fractional urate excretion in 1. Urinary N-acetyl-beta-glucosaminidase (NAG) excretion increased in 7; the mean urinary NAG/creatinine ratio was raised to twice the upper limit of the normal range. Renal haemosiderosis due to chronic intravascular haemolysis could cause tubular injury.

Focal sclerosing glomerulopathy. Risk factors of progression and optimal mode of treatment

Focal sclerosing glomerulopathy and especially focal segmental glomerulosclerosis (FSGS) have been recognized as a distinct clinical entity, however, there still exist controversies in terms of prognostic risk factors of progression and optimal mode of treatment. A total of 32 patients (2 with focal global sclerosis; FGS, the remainder with FSGS) were followed up for a mean period of 82 months (3-240 months). Fourteen presented with nephrotic syndrome and 18 had proteinuria with or without hypertension. Thirteen patients, all of whom except 1 were nephrotic, received steroid treatment with or without other immunosuppressive agents (cyclophosphamide/cyclosporin A/azathioprine). Three of the steroid-treated remained stable in complete remission; 5 nephrotic non-responders had renal death. The mean slope of 1/creatinine versus time for steroid-treated and non-treated groups was -0.23 and -0.043, respectively (p = 0.04), suggesting that nephrotic range proteinuria might be prognostically important. However, for the population of FSGS/FGS as a whole, only the initial serum creatinine predicted renal survival (p = 0.001 by Cox's regression model). Hypertension and hypercholesterolaemia were not important variables by themselves. Nevertheless, we found that the 9 patients treated with antihyperlipidaemics (gemfibrozil/probucol/cholestyramine/maxEPA) fared better, mean slope being -0.023 versus -0.103 for non-treated, though not reaching statistical significance (p = 0.96). Controlled prospective study involving a larger number of patients might be worthwhile.

The physical state of human papillomavirus type 16 DNA in cervical carcinomas of Hong Kong Chinese

The presence of human papillomavirus (HPV) in 15 cervical carcinoma specimens obtained from Hong Kong Chinese patients was analyzed by Southern blot hybridization studies. In nine (60%) of them, HPV 16 genomes were detected, while two others (13.3%) were found to harbor HPV DNA of unknown type closely related to HPV 16. All of them were classified as squamous cell carcinomas according to WHO guidelines. In addition, the presence of HPV 18 was shown in another two (13.3%) squamous cell carcinoma samples. Among the nine tumors harboring HPV 16, four specimens (44.4%) have HPV in integrated forms, while four others (44.4%) have HPV in episomal forms. The simultaneous presence of both episomal and integrated forms was demonstrated in the remaining tissue sample (11.2%). The result obtained here indicates a strong association between HPV infection and cervical carcinogenesis in Hong Kong Chinese, with HPV 16 prevalent in squamous cell carcinoma. Moreover, the persistence of HPV 16 episomes in some of the tumor specimens suggests that extrachromosomal HPV DNA, possibly acting synergistically with other oncogenic factors, is also capable of inducing cervical cancer.

Correction of anemia in patients on continuous ambulatory peritoneal dialysis with subcutaneous recombinant erythropoietin twice a week: a long-term study

Subcutaneous recombinant human erythropoietin (rHuEPO) was given for 12 months twice weekly to 10 patients on continuous ambulatory peritoneal dialysis (CAPD) with anemia (hemoglobin less than 9.0 mg/dl). All patients responded to a median weekly dose of between 37.5 to 100 (mean 55 to 105) units/kg and reached a target hemoglobin of 10-12 mg/dl in a mean of 11.7 weeks (range 5-24). Serum iron, iron saturation and ferritin were significantly lower and serum potassium was significantly higher than the pre-treatment level from 1 month onwards. Five patients without pre-treatment iron overload required oral iron supplement and 3 required oral potassium-binding resin. No significant change in other serum biochemical parameters was observed. Blood pressure remained stable during the treatment period but additional or increased dosage of antihypertensive drugs was required in 5 patients. Peritoneal small solute clearance and ultrafiltration and residual renal clearance did not change significantly after correction of anemia. The incidence of peritonitis and exit site infection was similarly unaffected. One patient developed a severe headache which was not associated with hypertension and responded to withdrawal of rHuEPO treatment. Most of the remaining patients showed improvement in subjective well-being. It was concluded that the subcutaneous route twice a week is a safe, convenient and cost-effective way to administer rHuEPO to patients on CAPD.

Amelioration of gentamicin nephrotoxicity by phospholipids

The effect of phospholipids on gentamicin-induced nephrotoxicity was studied in Sprague-Dawley rats. Group 1a (5 rats) were given daily intraperitoneal injections of 100 mg/kg of gentamicin and sacrificed on day 7. Group 1b (10 rats) were similarly treated but were sacrificed on day 14. Group 2a (5 rats) were given 30 mg/kg of phospholipids for 6 days and sacrificed on day 7, serving as phospholipid controls. Group 2b (5 rats) were similarly treated, and from day 7 onwards daily intraperitoneal injections of 100 mg/kg of gentamicin were given while oral phospholipids were continued until the rats were sacrificed 7 days after gentamicin treatment. Group 2c (10 rats) were treated in the same manner as group 2b but the animals were sacrificed on day 28 after gentamicin treatment. Group 3 (10 rats) were given 30 mg/kg of phospholipids concurrently with intraperitoneal gentamicin injections and were sacrificed on day 28. Protein concentrations, N-acetyl-beta-glucosaminidase (NAG) activities and creatinine were measured in 24-h urine samples. Serum creatinine concentrations were measured in blood samples and 24-h creatinine clearance calculated. Gentamicin concentrations were determined in kidney tissues from which sections were also taken for light- and electron-microscopy. Results showed that gentamicin induced a marked increase in NAG and protein excretion, and a marked decrease in creatinine clearance with six rats succumbing to uraemia. Phospholipid treatment, whether started before or concurrently with gentamicin injections, reduced gentamicin-induced nephrotoxicity. The rats did not lose weight. Urinary excretion of NAG and protein was significantly reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical experience with pefloxacin in patients with urinary tract infections

A total of 27 patients, 21 of them females, with a median age of 56 were treated with pefloxacin for urinary tract infections. Some 74% of these infections were associated with upper tract symptoms, and Escherichia coli was the most common causative micro-organism (75% of cases). Fifteen patients had co-existent diseases with/without urological abnormalities. All strains of E coli were sensitive to pefloxacin; Actinobacter and one strain of Klebsiella and Streptococcus faecalis were resistant. Two patients who defaulted and one who had an initial negative bacterial culture were excluded from the analysis of the outcome. The overall bacteriological cure rate at four to eight weeks was 87.5% (21/24). The incidence of possible side-effects was high, occurring in 59% of the patients. Nausea, dizziness and vomiting were the most common. These were mild and did not require termination of treatment. Peripheral neuropathy, which disappeared four weeks after stopping pefloxacin, occurred in one patient.

Integration of HPV-16 DNA in cervical carcinoma cell line CC3/CUHK3 and its xenografts

A recently established cell line, designated CC3/CUHK3, derived from a squamous cell carcinoma of the uterine cervix of a Hong Kong Chinese patient was investigated for its association with human papillomavirus (HPV) by Southern blot hybridization studies. A "grafted tumour" or xenograft of CC3/CUHK3 has also been successfully established in athymic mice, which showed similar histology to that of the original biopsy. The epithelial nature of the xenografts, like the original biopsy. The epithelial nature of the xenografts, like the original tumour specimen, was also confirmed by transmission electron microscopy which demonstrated the presence of desmosomes and tonofilaments. Moreover transmission electron microscopic examination revealed no HPV particle in either the tumour biopsy or the xenograft tissues. Analysis of the DNA samples extracted from the cervical cancer cell line and the xenograft tissues derived from it showed the presence of HPV type 16 DNA. No DNA sequence related to HPV type 6, 11, or 18 was demonstrated. The viral DNA was found to be integrated into the cellular genome at multiple sites as single copy or head-to-tail tandem repeats. Deletion or rearrangement of the HPV DNA had probably occurred on or subsequent to integration. Viral sequence deletion has also been observed in the grafted tumours derived from CC3/CUHK3.

Urinary tract infections in post-renal transplant patients

The overall incidence of urinary tract infections (UTIs) in our renal transplant population was 30.9%, i.e. 0.15 episode per patient-year. UTIs occurred more often within the first 3 months (60%) of transplantation. Fifty per cent of UTIs were asymptomatic. Recurrences were common. Acute tubular necrosis and cellular rejections were important associations. UTIs had little effect on graft function and survival up to 3 years post-transplant.

Comparison of captopril and enalapril in the treatment of hypertension in patients with non-insulin dependent diabetes mellitus and nephropathy

Eighteen patients with non-insulin dependent diabetes mellitus (NIDDM), hypertension and nephropathy were randomized to receive captopril or enalapril for 6 months. Two patients with serum creatinine of greater than 400 mumol/l had to be excluded from the study because of rapidly deteriorating renal function after starting treatment. Of the remaining patients, 7 received captopril and 9 received enalapril. Blood pressure control was achieved in about 50% of patients with either drug alone. Serum creatinine and creatinine clearance were unchanged in both groups but there was a greater tendency for the former to increase in patients with higher pretreatment values. Proteinuria was reduced at 1 month only in the enalapril group which also showed a significant elevation of serum potassium after treatment. Captopril and enalapril have only a modest antihypertensive action in patients with NIDDM and nephropathy. Their use in patients with renal insufficiency must be balanced against the risk of further aggravating the deterioration of renal function.

N-acetyl-beta-glucosaminidase in the localization of the site of urinary tract infections

Excretion of N-acetyl-beta-glucosaminidase was measured in 57 patients with urinary tract infections and in 19 normal subjects. The normal range was 0.17 to 1.16 iu/mmol creatinine. The mean NAG/creatinine ratio was 3.11 in 28 patients with upper, and 1.14 in 21 patients with lower urinary tract infection (p = 0.0006). However, even among those clinically defined as having lower urinary tract infections, 18% had NAG/creatinine ratios above the normal range. The mean NAG/creatinine ratio of 8 patients with lower urinary tract symptoms who had underlying uronephrological diseases/systemic diseases capable of causing nephropathy was intermediate between the value obtained in patients with upper, and that observed in patients with lower urinary tract infections.

The value of cytologic examination for nasopharyngeal carcinoma

Cytologic examination is useful in the diagnosis of NPC. The actual yield in exfoliative cytologic diagnosis can be improved by a better designed applicator. Metastatic NPC in lymph node FNA shows certain features that are diagnostic. Detection of EBNA can be done with smears from fine-needle aspirates and may help to exclude NPC from the diagnosis if they are negative.

Development of an automated human sperm quality system

A computer-automated system, including hardware and software components, is developed for objective assessment of human sperm density and other characteristics, including morphological abnormalities and motility. The hardware component essentially consists of an IBM AT, a relatively low-cost image processing board and other inexpensive commercially available instruments. On the other hand, the software component is developed through the incorporation of image analysis, pattern recognition and modelling techniques with the knowledge of human reproduction from the available literature. The whole system is expected to produce a practical and cost-effective means for the routine assessment of human semen quality.

Haematological changes after renal transplantation: differences between cyclosporin-A and azathioprine therapy

Haematological changes after renal transplantation in 76 patients were reviewed and the differences observed between patients treated with cyclosporin-A and prednisolone and those treated with azathioprine and prednisolone were compared. Erythrocytosis defined as haemoglobin concentration equal to or exceeding 17 g/dl occurred in 25% of patients treated with cyclosporin-A and in 11.4% of patients treated with azathioprine. Only one patient, who received cyclosporin-A, had clinical evidence of thrombosis. Eight patients treated with cyclosporin-A and five treated with azathioprine had therapeutic venesections. There was no difference in the incidence of putative risk factors for post-transplant erythrocytosis between the two groups.

Newcastle bone disease in Hong Kong: a study of aluminum associated osteomalacia

We measured serum aluminum concentrations in 104 haemodialysis patients from 3 centres in Hong Kong. We found that the 52 patients dialyzed in unit A had much higher mean aluminium levels (100 micrograms/L) than those from the other two units (61 and 39 micrograms/L respectively). In unit A, where water treatment by reverse osmosis had been introduced only recently, 30.8% of patients had fractures/looser zones, 46.2% had rugger-jersey spine and 28.8% had skeletal erosions. When these patients were divided into two groups according to whether their serum aluminium concentration was below or above 100 micrograms/l, the latter patients had significantly lower alkaline phosphatase, serum phosphate, and higher total prescribed dose of aluminium hydroxide. It was concluded that both dialysate aluminium and oral aluminium intake seemed to have contributed to the high incidence of osteomalacic fractures among Unit A patients. In eight of these patients serum aluminium increased by more than 150 micrograms/L after four weeks of receiving 1.5 g desferrioxamine twice weekly. Serial X-rays showed that the mean time after dialysis for the appearance of fractures/Looser zones was 72 months. Three patients developed fractures/Looser zones after successful renal transplantation; and it was postulated that the prompt excretion of aluminium permitted increased osteoclastic activity, resulting in fractures in these patients.

Minimal change glomerulopathy in two patients after thymectomy

Two myasthenia gravis patients developed nephrotic syndrome due to minimal change glomerulopathy 3 to 14 years after thymectomy for malignant thymoma. Impaired cellular and humoral immunity has been documented in patients with thymoma and persists after thymectomy. The occurrence of minimal change disease lends support to the hypothesis that the glomerulopathy is secondary to T-cell dysfunction, resulting in production of a lymphokine which increases glomerular basement membrane permeability.

Lipid metabolism in renal failure

Many patients with renal failure show abnormalities of lipid metabolism. Hypertriglyceridemia and low levels of high density lipoprotein (HDL) cholesterol are frequent abnormalities in uremic patients. The hypertriglyceridemia and low HDL cholesterol are thought to result from decreased lipoprotein lipase activity. The decreased levels of hepatic lipase observed in renal failure may account for the presence of intermediate density lipoproteins (IDL) and the high HDL2 subfraction. The risk factor for coronary artery disease expressed as the ratio of total cholesterol to HDL cholesterol is elevated in renal failure patients, especially in those with hypertriglyceridemia. Treatment of renal patients with gemfibrozil partially reverses many of the lipid abnormalities including the low HDL cholesterol. However, only the HDL3 subfraction increased while HDL2 remained unchanged.

A randomized prospective trial of three different regimens of treatment of peritonitis in patients on continuous ambulatory peritoneal dialysis

A randomized prospective study was undertaken in patients on continuous ambulatory peritoneal dialysis (CAPD) to evaluate the efficacy of three different antibiotic regimens for the treatment of peritonitis. There were 39 episodes in each treatment group. Patients were treated with intraperitoneal (IP) cephalothin (250 mg/L) and tobramycin (8 mg/L) in group 1, oral ofloxacin (400 mg loading followed by 300 mg daily) in group 2, and a combination of ofloxacin (400 mg followed by 300 mg daily) and rifampicin (300 mg daily). Treatment duration was 10 days. The average culture-positive rate was 75%. The overall cure rate was 80.6% with IP antibiotics, 78.4% with oral ofloxacin, and 81.1% with ofloxacin and rifampicin. After the exclusion of tunnel infections and episodes of peritonitis due to Pseudomonas and resistant organisms, the corresponding figures were 100%, 90.6%, and 93.7%, respectively. Side effects were minimal with IP treatment and with oral ofloxacin, but severe nausea and vomiting occurred in some cases with the combination of ofloxacin and rifampicin. It was concluded that oral ofloxacin is an acceptable first-line therapy for peritonitis in CAPD patients.

Sustained-release bezafibrate corrects lipid abnormalities in patients on continuous ambulatory peritoneal dialysis

A study was undertaken in 24 Chinese patients on maintenance continuous ambulatory peritoneal dialysis, using bezafibrate in its sustained-release form to correct lipid abnormalities. Six patients who received 400 mg/day developed severe muscle weakness with grossly elevated creatine phosphokinase activities within 3 weeks. The drug was discontinued and the symptoms disappeared. The remaining 18 patients received 400 mg/week for 8 weeks. There was a significant decrease in serum triglyceride (2.74 +/- 0.33 to 1.86 +/- 0.17 mmol/l at the 4th week and 1.65 +/- 0.4 mmol/l at the 8th week). Concomitantly, serum total cholesterol decreased. Serum high-density lipoprotein cholesterol increased significantly (from 1.18 +/- 0.082 to 1.36 +/- 0.060 mmol/l at the 4th week and 1.40 +/- 0.103 mmol/l at the 8th week). Post-heparin lipoprotein and hepatic lipases were measured by a substrate-specific method. The former increased significantly (p = 0.000) after bezafibrate treatment while the latter did not change. All parameters of lipid metabolism returned towards baseline 4 weeks after discontinuation of therapy. The drug was well tolerated at 400 mg/week and there was no significant rise in serum creatine phosphokinase.