Rectal impalement injury through the pelvis, abdomen and thorax

Impalement rectal injuries with intraperitoneal organ injuries are rare. It is even rarer for such injuries to result in pelvic, abdominal and thoracic internal injuries. We present the case of a 39-year-old man who was admitted after an assault where a broken broomstick was inserted forcibly into his rectum. Surgery revealed penetration through the rectum, dome of the bladder, mesentery, liver and right lung. The patient survived following management by a multispecialty surgical team. Our literature review identified four similar cases with one fatality only. Prognosis seems to be good in these types of injuries provided there is an early presentation, the penetrating object is left in situ before the operation and, most importantly, an organised team approach to deal with the various injuries.

Women with placenta praevia and antepartum haemorrhage have a worse outcome than those who do not bleed before delivery

We set out to assess the maternal and neonatal outcomes of women with placenta praevia and antepartum haemorrhage (APH) between 1991 and 1997, compared with woman with a diagnosed placenta praevia who did not bleed. The demographic data, maternal and perinatal outcomes of 159 women with antepartum haemorrhage were compared with 93 women without antepartum haemorrhage in a retrospective study. Women with antepartum haemorrhage had the diagnosis of placenta praevia confirmed at an earlier gestation. More women with antepartum haemorrhage received antenatal steroids and tocolytic agents, and had emergency caesarean sections. The majority of women with bleeding had an emergency caesarean section for antepartum haemorrhage and more delivered early because of fetal distress. There were more preterm deliveries in women with antepartum haemorrhage. The mean birth weight was 2.69 kg in the women with antepartum haemorrhage and 3.06 kg in those without. More infants in the bleeding group had a low Apgar score at the first minute, respiratory distress syndrome, and admission to special baby care and neonatal intensive care unit. It is concluded that there is an increased risk of premature delivery in women with antepartum haemorrhage and placenta praevia. Aggressive management, tocolysis and cervical cerclage should be explored further to improve the perinatal outcome. Women without antepartum haemorrhage can be managed on an outpatient basis.

The placentas of patients with severe acute respiratory syndrome: a pathophysiological evaluation

Aims

The pathology of the placentas delivered from pregnant women who had severe acute respiratory syndrome (SARS) in Hong Kong was studied.

Methods

The pathology of the placentas was retrospectively studied in detail and compared with control sets. The clinical data of the women and neonates were also reviewed.

Results

A total of seven placentas were studied. The placentas from two women convalescent from SARS in the first trimester were normal. In three placentas delivered in the acute stage of SARS, there were increases in intervillous or subchorionic fibrin which might be related to disturbances in maternal placental blood flow due to the hypoxic respiratory disease. Extensive fetal thrombotic vasculopathy (FTV) with sharply demarcated zones of avascular fibrotic villi was noted in the placentas of two patients convalescent from SARS in the third trimester. Both pregnancies had intrauterine growth retardation, oligohydramnios and newborns small for gestation. The aetiology of the FTV might be related to thrombotic tendency due to SARS or placental hypoxia.

Conclusions

This report highlights placental pathology that was probably the result of pathophysiological alteration of the maternal fetal unit during SARS. Further studies are required to delineate the relationship between severe maternal respiratory disease, placental pathology and pregnancy outcome.

Intracranial multiple myeloma involving the dura

Meningeal involvement in multiple myeloma is rare. We report a case in which a patient with a history of multiple myeloma presented with neurological deficit due to meningeal involvement.

General gynaecology: Intrauterine lignocaine as an anaesthetic during endometrial sampling: a randomised double-blind controlled trial

OBJECTIVE

To evaluate the effectiveness of intrauterine lignocaine as an anaesthetic during endometrial sampling.

DESIGN

Prospective, randomised, double-blind, placebo-controlled trial.

SETTING

Outpatient gynaecological minor operation unit in a public hospital.

POPULATION

Two hundred premenopausal women scheduled for endometrial sampling because of abnormal uterine bleeding.

METHODS

Transcervical intrauterine instillation of 5 mL of 2% lignocaine or 5 mL of normal saline before performing endometrial sampling with vacuum aspirator.

MAIN OUTCOME MEASURES

Evaluation of pain associated with the procedure using a visual analogue scale.

RESULTS

The use of intrauterine lignocaine reduced pain during suction curettage in endometrial sampling.

CONCLUSIONS

Transcervical instillation of lignocaine reduced pain during endometrial sampling.

BRAF and NRAS mutations are uncommon in melanomas arising in diverse internal organs

BACKGROUND

Malignant melanoma arising from different body compartments may be associated with differing aetiological factors and clinical behaviour, and may manifest diverse molecular genetic profiles. Although many studies have focused on cutaneous melanoma, little is known of mucosal and other types of melanoma. In particular, malignant melanoma of soft parts is different from other melanomas in many respects, yet manifests a common melanocytic differentiation. Mutation of BRAF is now known to be common in cutaneous melanomas, and raises possible new therapeutic options of anti-RAF treatment for these patients. Few data are available for non-cutaneous melanomas.

AIMS

To study the incidence of BRAF and NRAS mutations in melanomas arising in diverse internal organs.

METHODS

Fifty one melanomas from various internal organs were investigated for BRAF and NRAS mutation by direct DNA sequencing.

RESULTS

BRAF and NRAS mutations were found in two and five mucosal melanomas arising from the aerodigestive and female genital tracts (n = 36). Their occurrence is mutually exclusive, giving a combined mutation incidence rate of 19.4% in mucosal melanomas. Both BRAF and NRAS mutations were absent in malignant melanoma of soft parts (n = 7). BRAF mutation was also absent in uveal melanoma (n = 6), but was seen in two of five cutaneous melanomas. The incidence of BRAF or combined BRAF/NRAS mutations in all non-cutaneous groups was significantly lower than published rates for cutaneous melanomas.

CONCLUSION

Each melanoma subtype may have a unique oncogenetic pathway of tumour development, and only a small fraction of non-cutaneous melanomas may benefit from anti-RAF treatment.

Clinicopathological features and prognostic factors of cutaneous melanoma among Hong Kong Chinese

Cutaneous melanoma is rare among Chinese people. The clinicopathologic features and prognostic factors of 63 Hong Kong ethnic Chinese cases were analysed. We found that the mean age of onset was 65.5 years with a female : male ratio of 1 : 1.33. Forty-two (66.7%) patients had their tumours on their feet. More than 50% had the acral lentiginous histologic subtype. The mean tumour thickness was 5.73 mm with 92.1% (n = 58) having a Clark's level of III or more. Of the tumours, 57.1% were ulcerated. Stage I and II tumours comprised 73% (n = 46) while stage III and IV tumours made up of 26% (n = 17). The 1-, 3- and 5-year survival rates were 75%, 30% and 17%, respectively. Univariate analysis for overall survival showed that advanced clinical staging (stage III and IV), tumour ulceration and thicker tumour (>4 mm) had a significantly poorer prognosis. Multivariate analysis demonstrated that advanced clinical staging was the most decisive prognostic factor followed by tumour ulceration. Our study showed that cutaneous melanoma in Chinese people is a disease predominantly of an older age group with the acral lentiginous histologic type located mainly on the feet. The prognosis depends on clinical staging and ulceration status.

Molecular phylogenies of Blastocystis isolates from different hosts: implications for genetic diversity, identification of species, and zoonosis

Small-subunit (SSU) rRNA gene sequences were obtained by PCR from 12 Blastocystis isolates from humans, rats, and reptiles for which elongation factor 1alpha (EF-1alpha) gene sequences are already available. These new sequences were analyzed by the Bayesian method in a broad phylogeny including, for the first time, all Blastocystis sequences available in the databases. Phylogenetic trees identified seven well-resolved groups plus several discrete lineages that could represent newly defined clades. Comparative analysis of SSU rRNA- and EF-1alpha-based trees obtained by maximum-likelihood methods from a restricted sampling (13 isolates) revealed overall agreement between the two phylogenies. In spite of their morphological similarity, sequence divergence among Blastocystis isolates reflected considerable genetic diversity that could be correlated with the existence of potentially >/=12 different species within the genus. Based on this analysis and previous PCR-based genotype classification data, six of these major groups might consist of Blastocystis isolates from both humans and other animal hosts, confirming the low host specificity of Blastocystis. Our results also strongly suggest the existence of numerous zoonotic isolates with frequent animal-to-human and human-to-animal transmissions and of a large potential reservoir in animals for infections in humans.

Molecular phylogenies of Blastocystis isolates from different hosts: implications for genetic diversity, identification of species, and zoonosis

Small-subunit (SSU) rRNA gene sequences were obtained by PCR from 12 Blastocystis isolates from humans, rats, and reptiles for which elongation factor 1alpha (EF-1alpha) gene sequences are already available. These new sequences were analyzed by the Bayesian method in a broad phylogeny including, for the first time, all Blastocystis sequences available in the databases. Phylogenetic trees identified seven well-resolved groups plus several discrete lineages that could represent newly defined clades. Comparative analysis of SSU rRNA- and EF-1alpha-based trees obtained by maximum-likelihood methods from a restricted sampling (13 isolates) revealed overall agreement between the two phylogenies. In spite of their morphological similarity, sequence divergence among Blastocystis isolates reflected considerable genetic diversity that could be correlated with the existence of potentially >/=12 different species within the genus. Based on this analysis and previous PCR-based genotype classification data, six of these major groups might consist of Blastocystis isolates from both humans and other animal hosts, confirming the low host specificity of Blastocystis. Our results also strongly suggest the existence of numerous zoonotic isolates with frequent animal-to-human and human-to-animal transmissions and of a large potential reservoir in animals for infections in humans.

Histopathological findings of the nose of Down syndrome abortuses

Recent reports of absent nasal bone in fetuses with Down syndrome have sparked much interest in the use of this finding for the screening of Down syndrome. We describe the histopathological findings of nasal bones of two fetuses with Down syndrome, one with absence and the other with normal ossification of the nasal bone. We propose that histopathological examination of the nasal bone could improve the accuracy of diagnosis of nasal hypoplasia among Down syndrome abortuses.

The relative risk of 'fetal distress' in pregnancy associated with meconium-stained liquor at different gestation

Pregnancies complicated with meconium-stained liquor are regarded as at risk of fetal distress. Evidence from animal and human studies indicate that passage of meconium may be related to fetal maturity. This retrospective study attempts to quantify the relative risk of non-reassuring cardiotocography or 'fetal distress' in pregnant women complicated by meconium-stained liquor for preterm, term and post-term pregnancies. A total of 9542 singleton pregnancies, delivered in a tertiary obstetric unit in Hong Kong between 1 July 1996 and 31 June 1999, were included in the study. Of these pregnancies, 1946 (20.4%) were identified as having meconium-stained liquor, ranging from thin to thick staining. There was a strong association between incidence of meconium-stained liquor (P < 0.0005) and moderate/thick meconium-stained liquor with advanced gestational age. The incidence of non-reassuring cardiotocography in women presenting with meconium-stained liquor was significantly higher (9.8% vs. 6.4%). The relative risk of non-reassuring cardiotocography in women with meconium-stained liquor increased with more advanced gestation. Close fetal surveillance during labour is required among these pregnancies. Premature labour is associated with higher incidence of fetal distress but the presence of meconium did not pose an additional risk.

Fetal bradycardia in the first trimester: an unusual presentation of atrial extrasystoles

We report a fetus with fetal bradycardia at 13 weeks of gestation secondary to atrial extrasystoles. The fetus subsequently developed paroxysmal supraventricular tachycardia and hydrops fetalis. The cardiac arrhythmia recovered spontaneously without any medical intervention. This case illustrates that atrial ectopic beats can present in the first trimester with fetal bradycardia. Rapidly evolving hydrops fetalis secondary to supraventricular tachycardia can develop, warranting close monitoring with weekly heart rate assessment. Fetal bradycardia secondary to atrial extrasystole should be differentiated from first trimester sinus bradycardia and those associated with major structural cardiac abnormality, which have a high fetal loss rate.

An ISFET-based immunosensor for the detection of beta-Bungarotoxin

An ion-sensitive field effect transistor (ISFET)-based immunosensor was developed to detect/quantitate beta-Bungarotoxin (beta-BuTx), a potent presynaptic neurotoxin from the venom of Bungarus multicinctus. A murine monoclonal antibody (mAb 15) specific to beta-BuTx was immobilized onto silicon nitride wafers after silanization and activation with glutaraldehyde. A chip based enzyme linked-immunosorbantassay (ELISA) was performed to ascertain antigen binding to the immobilized antibody. To develop an electrochemical immunosensing system for the detection/quantitation of beta-BuTx, an ISFET was used as a solid phase detector. MAb 15 was immobilized on the gate region of the ISFET. The antigen antibody reaction was monitored by the addition of urease conjugated rabbit anti-beta-BuTx antibodies. The sensor can detect toxin level as low as 15.6 ng/ml. The efficacy of the sensor for the determination of beta-BuTx from B. multicinctus venom was demonstrated in mouse model. Toxin concentration was highest at the site of injection (748.0+/-26 ng/ml) and moderate amount was found in the plasma (158.5+/-13 ng/ml).

Does sweeping of membranes beyond 40 weeks reduce the need for formal induction of labour?

OBJECTIVE

To assess the efficacy of sweeping of membranes beyond 40 weeks of gestation in reducing the incidence of induction of labour, when induction was planned at 42 weeks.

DESIGN

Prospective randomised controlled trial.

SETTING

A regional obstetric unit in Hong Kong.

POPULATION AND METHODS

A total of 120 women with certain gestational age, determined by early pregnancy ultrasound scan, were recruited from 1st July, 1998 to 31st December, 1999. Sixty women were randomly allocated to sweeping of membranes and the other 60 women acted as control. The satisfaction for women allocated to sweeping of membranes was assessed by a questionnaire after the procedure. The two groups were assessed on intention-to-treat basis.

MAIN OUTCOME MEASURES

The incidence of formal induction of labour was compared between the two groups. Possible complications of sweeping of membranes such as rupture of membranes, intrapartum infection, postpartum infection, and neonatal infection were also assessed. Maternal and perinatal outcomes were also assessed.

RESULTS

The recruitment to delivery interval was significantly shorter among women who had sweeping of membranes (3.2 versus 4.2 days, P < 0.05). The incidence of induction of labour was comparable (35.5% versus 38%, RR 0.91, 95% CI 0.57 - 1.46). The incidences of caesarean section and assisted vaginal delivery were comparable. The incidences of premature rupture of membranes, intrapartum, and postpartum infection were comparable. The perinatal outcomes were also comparable between the two groups. Up to 70% of women found that this procedure was associated with significant discomfort. One third of these women complained of significant pain.

CONCLUSIONS

Sweeping of membranes beyond 40 weeks does not reduce the need for formal induction of labour at 42 weeks. Although it is safe, the majority of women felt uncomfortable during the procedure.

A randomised placebo-controlled trial of vaginal misoprostol for cervical priming before hysteroscopy in postmenopausal women

OBJECTIVE

To investigate the effectiveness of misoprostol given vaginally for cervical priming before hysteroscopy in postmenopausal women.

DESIGN

Double-blind randomised controlled study.

SETTING

Regional hospital, Hong Kong.

PARTICIPANTS

One hundred women with postmenopausal bleeding scheduled for hysteroscopy from October 1998 to September 2001 were randomly assigned to receive either misoprostol or placebo vaginally before the operation.

MAIN OUTCOME MEASURES

The number of women requiring cervical dilatation, outcome of hysteroscopy and side effects of the medication were assessed.

RESULTS

Forty-eight women receiving misoprostol and 48 women receiving placebo were compared. The mean degree of endocervical diameter estimated by Hegar's dilator was similar between the treatment group and the control group. A similar number of women in the treatment group and the control group required cervical dilatation. The operative times for both groups were similar. The incidence of side effects was comparable in both groups. The most common side effects for misoprostol were febrile episodes and diarrhoea. There was no cervical tear nor uterine perforation encountered in both groups. The mean duration of hospital stay in both groups were similar. Subanalysis of results were similar in women receiving vaginal medication at least five hours before the operation.

CONCLUSION

Vaginal misoprostol was not shown to reduce the need for cervical dilatation in postmenopausal women. It cannot convert diagnostic hysteroscopy from a hospital procedure into an office one in postmenopausal women with tight cervical os.

Sex selection in practice among Hong Kong Chinese

The aim of this study is to identify factor(s) influencing imbalance in the sex distribution of children (more children of the same sex) of the multiparous women attending an antenatal clinic in Hong Kong. A retrospective study was carried out to compare the expected and observed sex ratios of babies born to women with one previous live birth and women with two. All singleton pregnant women of parities 1 and 2 delivering after 22 weeks of gestation, between 1 July 1996 and 30 June 1998, were included. A total of 2604 women of parity 1 and 752 women of parity 2 were included. The sexes of the children of parity 1 women and the sex distribution of their newborns were consistent with the predicted value. The parity 2 women were more likely to have third children if their previous children were of the same sex (p-value < 0.001). This implies that the parity 2 women attending our antenatal clinic had third pregnancies because of social, economical or environmental reasons. Our parity 2 women with two daughters were more likely to have sons (p < 0.05). Thus, biological or parental factors were unlikely to be important in influencing the sex of the newborn. This suggested that sex selection or sex-selective abortion might be practiced among Hong Kong Chinese women.

Exposure of Blastocystis species to a cytotoxic monoclonal antibody

A recently described cytotoxic monoclonal antibody (mAb 1D5) raised against Blastocystis hominis isolate B, was tested for reactivity with 13 different isolates of Blastocystis. The isolates used were previously isolated from humans, rats and reptiles and were maintained as axenised cultures throughout the course of this study. Five B. hominis isolates (B, C, E, G and H) were found to react with mAb 1D5 in immunoblotting studies and the indirect fluorescence antibody test. The pattern of fluorescence observed for all five isolates was diffuse and patchy. Immunoblotting studies revealed that mAb 1D5 reacted with a 29-30-kDa protein found in all five isolates. Results of a cytotoxic assay showed that the mAb exhibited a complement-independent cytotoxic effect on all the exposed isolates. Microscopic observations showed differences in morphology between the Blastocystis cells exposed and unexposed to mAb. Acridine orange staining performed on both exposed and unexposed cells showed similar internal structures when viewed under fluorescence microscopy.

Subfrontal schwannoma masquerading as meningioma

Intracranial schwannomas not associated with cranial nerves are rare and seldom encountered in the subfrontal region. We report a case of subfrontal schwannoma in a 21-year-old man who presented with seizures. Radiological features resembled an olfactory groove meningioma. The histological diagnosis of schwannoma was confirmed by immunohistochemical staining with S-100 and electron microscopy. We advocate the use of immunohistochemistry and electron microscopy as adjuncts to conventional light microscopy in differentiating schwannomas from meningiomas. Surgery remains the main therapeutic modality and complete excision is associated with cure.

Brain abscess formation in radiation necrosis of the temporal lobe following radiation therapy for nasopharyngeal carcinoma

BACKGROUND

Radiation necrosis is a known complication following radiation therapy for extracranial as well as intracranial tumours. However, brain abscess formation in radiation necrosis has not been reported in the literature. We report the clinical data of 6 patients suffering from this condition.

METHOD

Twenty-eight patients with radiation necrosis of the temporal lobe following radiotherapy for nasopharyngeal carcinoma were treated surgically at the Department of Neurosurgery, Queen Elizabeth Hospital, Hong Kong between January 1992 and July 1999. Of these, 6 cases were complicated by brain abscess formation. The clinical data of these 6 patients are retrospectively reviewed.

FINDINGS

The patients were 5 males and 1 female, ranging in age from 41 to 67 years. Three patients had previous treatment with steroids for the symptomatic radiation necrosis. A history of nasal infection or otitis media was recognised in all 6 patients. All patients were treated surgically by temporal lobectomy and excision of the necrotic tissue together with the abscess cavity. Intra-operatively, a bony defect was observed between the middle cranial fossa and the sphenoid sinus in 3 patients and the bony defect was repaired with a temporalis muscle flap. The species of organisms could only be identified in 3 patients. In 3 patients, the pus smear was positive but the culture was negative. Subsequently, 4 patients recovered and 2 patients died.

INTERPRETATION

Cerebral radiation necrosis is a predisposing cause of brain abscess formation. Surgical excision is recommended as the treatment of choice in this group of patients.

Acute hemorrhage in late radiation necrosis of the temporal lobe: report of five cases and review of the literature

Hemorrhage in late cerebral radiation necrosis is a rare complication after radiotherapy for intracranial and extracranial neoplasms. We report 5 cases of acute hemorrhage in late radiation necrosis of the temporal lobe following radiation therapy for nasopharyngeal carcinoma. In a review of the literature, the authors identified a total of 27 such cases. The interval period between the onset of hemorrhage and cranial irradiation is long (mean = 7.8 years). The most prominent histological feature was the proliferation of large, dilated and thin-walled new blood vessels in a background of gliosis and fibrinoid necrosis of vessels. Rupture of these thin-walled new blood vessels is the proposed mechanism of hemorrhage in this condition.

Spontaneous uterine perforation of pyometra. A report of three cases

BACKGROUND

Spontaneous perforation of pyometra is a rare cause of generalized peritonitis; only 17 cases have been reported.

CASES

Three cases of spontaneous perforation of pyometra occurred; two were associated with carcinoma of the cervix. All were treated with exploratory laparotomy and drainage. The first patient died of recurrent carcinoma of the cervix five months after laparotomy. The second patient died of septic shock shortly after the operation. The third patient made a good postoperative recovery.

CONCLUSION

Pyometra is a serious medical condition, because of both its association with malignant disease and the danger of spontaneous perforation, which carries significant morbidity and mortality. Although rare, ruptured pyometra should be considered in the differential diagnosis of acute abdomen in elderly women, especially those with malignant disorders of the genital tract. The treatment of pyometra rupture is immediate laparotomy, peritoneal lavage and drainage, or simple hysterectomy.

Blastocystis elongation factor-1alpha: genomic organization, taxonomy and phylogenetic relationships

The elongation factor-1 alpha (EF-1alpha) is a highly conserved ubiquitous protein that is involved in translation and is desirable for use in phylogenetic studies on Blastocystis, an enigmatic intestinal parasite with a contentious taxonomic position. In the present study, a PCR product (BEalpha) that codes for a major part of the coding region of the EF-lalpha protein was amplified. Genome walking experiments together with cloning were implemented to elucidate the 5' and 3' ends of the EF-1alpha gene of the human isolate, Blastocystis hominis C. The genomic organization and the potential transcription factor binding sites of the 5' end of B. hominis C EF-1alpha were identified. A comparative study on the deduced amino acid sequences of BEalpha of 13 Blastocystis isolates from various hosts was done to evaluate the phylogenetic relationship among the species. A phylogenetic reconstruction analysis with other eukaryotic EF-1alpha sequences was carried out to trace the phylogenetic position of Blastocystis among eukaryotic organisms.

Iron K Line Variability in the Low-Luminosity Active Galactic Nucleus NGC 4579

We present results of new ASCA observations of the low-luminosity active galactic nucleus (LLAGN) NGC 4579 obtained on 1998 December 18 and 28, and we report on the detection of variability of an iron K emission line. The X-ray luminosities in the 2-10 keV band for the two observations are nearly identical (LX approximately 2x1041 ergs s(-1)), but they are approximately 35% larger than that measured in 1995 July by Terashima et al. An Fe K emission line is detected at 6.39+/-0.09 keV (source rest frame), which is lower than the line energy 6.73+0.13-0.12 keV in the 1995 observation. If we fit the Fe lines with a blend of two Gaussians centered at 6.39 and 6.73 keV, the intensity of the 6.7 keV line decreases, while the intensity of the 6.4 keV line increases, within an interval of 3.5 yr. This variability rules out thermal plasmas in the host galaxy as the origin of the ionized Fe line in this LLAGN. The detection and variability of the 6.4 keV line indicates that cold matter subtends a large solid angle viewed from the nucleus and that it is located within approximately 1 pc from the nucleus. It could be identified with an optically thick standard accretion disk. If this is the case, a standard accretion disk is present at the Eddington ratio of Lbol/LEdd approximately 2x10-3. A broad disk-line profile is not clearly seen, and the structure of the innermost part of accretion disk remains unclear.

Evidence for a Black Hole and Accretion Disk in the LINER NGC 4203

We present spectroscopic observations from the Hubble Space Telescope that reveal for the first time the presence of a broad pedestal of Balmer line emission in the LINER galaxy NGC 4203. The emission-line profile is suggestive of a relativistic accretion disk and is reminiscent of double-peaked transient Balmer emission observed in a handful of other LINERs. The very broad line emission thus constitutes clear qualitative evidence for a black hole, and spatially resolved narrow-line emission in NGC 4203 can be used to constrain its mass, MBH</=6x106 M middle dot in circle, at 99.7% confidence. This value implies a ratio of black hole mass to bulge mass of less, similar7x10-4 in NGC 4203, which is less by a factor of approximately 3-9 than the mean ratio obtained for other galaxies. The availability of an independent constraint on central black hole mass makes NGC 4203 an important testbed for probing the physics of weak active galactic nuclei. Assuming MBH near the detection limit, the ratio of the observed luminosity to the Eddington luminosity is approximately 10-4. This value is consistent with advection-dominated accretion and hence with scenarios in which an ion torus irradiates an outer accretion disk that produces the observed double-peaked line emission. Follow-up observations will make it possible to improve the black hole mass estimate and study variability in the nuclear emission.

Rejuvenative facial lipomorphoplasty

Aging of the face is staged. Rejuvenation by restoration of structural volume deficit with sedimented autogenous fat micrografts harvested by gentle syringe lipoaspiration is described. Atraumatic technique, avoidance of desiccation, and gentleness in handling the fat micrografts are required for successful vascularization and take of the grafts.

Possible Evidence for Truncated Thin Disks in the Low-Luminosity Active Galactic Nuclei M81 and NGC 4579

M81 and NGC 4579 are two of the few low-luminosity active galactic nuclei that have an estimated mass for the central black hole, detected hard X-ray emission, and detected optical/UV emission. In contrast to the canonical "big blue bump," both have optical/UV spectra that decrease with increasing frequency in a nuLnu plot. Barring significant reddening by dust and/or large errors in the black hole mass estimates, the optical/UV spectra of these systems require that the inner edge of a geometrically thin, optically thick accretion disk lies at approximately 100 Schwarzschild radii. The observed X-ray radiation can be explained by an optically thin, two-temperature, advection-dominated accretion flow at smaller radii.

Characterization of protein profiles and cross-reactivity of Blastocystis antigens by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis

The protein profiles of Blastocystis hominis, B. lapemi, and B. ratti were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and species could be differentiated by this means as well as by Western-blot analysis with polyclonal antibodies. No intraspecies difference could be distinguished between the two B. hominis isolates or the three B. ratti isolates. Western-blot analysis showed extensive cross-reactivity of B. lapemi and B. hominis antigens with anti-B. ratti serum. Some of the cross-reactive antigens were glycoproteins as determined on the basis of their sensitivity to periodate treatment.

Development of Blastocystis hominis cysts into vacuolar forms in vitro

The development of cysts of Blastocystis hominis isolated from human feces by the Ficoll-Paque concentration method and cultured in Jones' medium containing 10% horse serum is described. The morphological changes were studied by light and transmission electron microscopy at different intervals for up to 48 h. The cysts developed into a large number of vacuolar forms within 24 h, and binary fission was the only mode of reproduction observed.

In vitro encystation and excystation of Blastocystis ratti

Cysts of Blastocystis ratti were produced in vitro by culturing the parasite in Iscove's modified Dulbecco's medium (IMDM) with increasing concentrations of horse serum. Yields up to 3 x 10(6) cysts/ml of culture medium were obtained after 72 h. Encystation efficiency was time, strain and inoculum size dependent. A viability of > 70% was determined by flow cytometry employing fluorescein diacetate and propidium iodide staining. The presence of chitin as a cyst wall component was demonstrated by Calcofluor White M2R staining with which cystic stages showed blue fluorescence. The changes in morphology during excystation were examined by transmission electron microscopy. The cyst enlarged in size and some vacuoles appeared within the condensed cytoplasm. The vacuoles were full of inclusions and small glycogen aggregates. Coalescence of the vacuoles led to central body formation. Glycogen deposits were prominent throughout the excystation process. Some cysts divided by binary fission before the completion of the excystation.

Well-differentiated papillary adenocarcinoma arising in a supratentorial enterogenous cyst: case report

OBJECTIVE AND IMPORTANCE

We report a case of a well-differentiated papillary adenocarcinoma arising in an supratentorial enterogenous cyst. The clinicopathological features of this case and a brief review of the literature are presented.

CLINICAL PRESENTATION

A 45-year-old woman presented with abrupt onset of sensory seizures and abnormal sensation on the left side of her face, left leg, and left arm. Radiological studies showed a cystic extraaxial tumor with mass effect in the right parietal area. The initial clinical impression was a metastatic lesion, and a comprehensive metastatic workup revealed no evidence of tumor elsewhere.

INTERVENTION

A gross total resection of the solid cystic tumor was achieved by a frontoparietal craniotomy. Sixteen months after the initial surgery, the patient presented with signs of increased intracranial pressure and a large parietal cyst. The cyst was fenestrated at the time of the second craniotomy.

CONCLUSION

A pathological study of the initial surgical material revealed it to be a well-differentiated papillary adenocarcinoma in association with an enterogenous cyst. The second surgical specimen consisted only of the benign cyst wall. The patient recovered uneventfully from the second surgery and was free of symptoms 6 months postoperatively. The importance of recognizing the rare possibility of malignant progression of a benign enterogenous cyst in the central nervous system is discussed.

Labour outcome of low-risk multiparas of 40 years and older. A case-control study

Between January 1, 1994 and December 31, 1997 a total of 76 low-risk multiparas of 40 years and older with spontaneous onset of labour were delivered and were compared with 152 younger (25-30 years-old) low-risk multiparas of similar parity in a case-control study. The labour and perinatal outcomes of the 2 groups were compared. The duration of the first stage of labour was longer (233 minutes versus 149 minutes, p<0.0005) in the older women. Significantly more labours of older multiparas were complicated by intrapartum fetal distress (6.6% versus 1.3%, p<0.05); received intramuscular analgesia (11.8% versus 2.6%, p<0.01); and had operative deliveries (17.1% versus 4.6%, p<0.01). The incidence of instrumental delivery (11.8% versus 3.9%, p<0.05) and Caesarean section (5.3% versus 0.7%, p<0.05) were higher among older multiparas. The incidences of Syntocinon augmentation of labour, prolonged second stage, episiotomy and third stage complications such as perineal tear, primary postpartum haemorrhage, and retained placenta were similar in both groups. Both groups had similar perinatal outcomes. These women should be treated as others with high-risk pregnancies with appropriate careful attention during labour such as continuous fetal heart rate monitoring. They should be counselled to be made aware of the increased risks during labour.

Cytopathic effect of Blastocystis hominis after intramuscular inoculation into laboratory mice

The present study investigated the pathogenesis of Blastocystis hominis by intramuscular injection of the organism into experimental mice. A total of 27 naïve BALB/c mice aged 6-8 weeks were injected in the leg muscle with axenic culture isolate B of B. hominis. Histological examination at different times revealed that B. hominis could produce a severe inflammatory reaction and myonecrosis. Most changes were observed at 6 h after injection and for up to 2-3 days. By 2 weeks the muscle had regained normal histology. There was infiltration of polymorphonuclear leukocytes (PML) into the injection site, indicating that B. hominis had a strong chemoattractant activity for PML.

Survival of Blastocystis hominis clones after exposure to a cytotoxic monoclonal antibody

Our previous studies have shown that monoclonal antibodies (MAbs) to Blastocystis hominis react mainly with carbohydrate epitopes, while 1 MAb (1D5) reacts specifically with a protein of 30.5 kDa. In the present study, 3 monoclonal antibodies (1D5, 1E7 and 4F7) were used in immunogold localization. 1E7 and 4F7 were found to react primarily with the surface coat, while 1D5 was plasma membrane-specific. In the presence of complement, only 1D5 exhibited a cytotoxic effect on B. hominis whereas 1E7 and 4F7 did not, suggesting that the surface coat of B. hominis could serve as an immunological barrier against host antibodies. Using a recently described agar plating method, only 1D5 exhibited significant (P < 0.01) complement-independent cytotoxicity to B. hominis, inhibiting colony growth at low concentrations. Parasites that had been exposed to 1D5 were morphologically smaller than those that were not exposed to this MAb. Colonies that grew in the presence of 1D5 were isolated and grown in liquid medium containing increasing amounts of the cytotoxic MAb. Two clones that grew well in liquid medium containing 1D5 were also able to develop into colonies in soft agar. This study has shown that the 30.5 kDa protein found on the plasma membrane of B. hominis is a functionally important protein and that not all cells within a certain population would be susceptible to the cytotoxic effects of 1D5. These findings suggest that a heterogenous population exists in continuously maintained cultures of B. hominis.

Experimental Blastocystis hominis infection in laboratory mice

Young (less than 8 weeks old) immunocompetent BALB/c mice became infected with Blastocystis hominis after inoculation of fecal cysts orally and of in vitro axenic-culture forms intracecally. This study confirmed that the fecal cyst was the form responsible for external transmission and that the mode of transmission was by the fecal-oral route. The infection was self-limiting and the infected BALB/c mice appeared normal except that some of them showed weight loss and lethargy. Both vacuolar and granular forms were found in the cecum, but only cyst forms were observed in the colon. Histological examination of the cecum and colon showed intense inflammatory-cell infiltration, edematous lamina propria, and mucosal sloughing. It is apparent that although B. hominis is not invasive, it is capable of causing pathogenesis in BALB/c mice.

Description of a Blastocystis species from Rattus norvegicus

Two isolates (WR1 and WR2) of Blastocystis from laboratory-bred Wistar rats were axenized by a method of colony growth in soft agar combined with antibiotic treatment. The colonies were cultured in Iscove's modified Dulbecco's medium (IMDM) and Bacto agar mixture supplemented with 10% horse serum in the presence of thioglycollate. The cells from the colonies had an ameboid outline with a central body. Large inclusions were seen in the central body of some cells. Some granular forms were also found. In the axenic culture of isolate WR2, about one-third of the organisms were granular forms. Cysts were found in the axenic culture of both isolates. This is the first report of such cyst formation in in vitro culture. The karyotypic patterns of both isolates of the rat Blastocystis were analyzed by pulsed-field gel electrophoresis (PFGE). A total of 13 chromosomal bands were separated, ranging from 1.86 Mb to 295 kb. The karyotypic patterns of the rat Blastocystis were different from those of B. hominis and reptilian Blastocystis. On the basis of the above-mentioned differences, the rat Blastocystis is assigned as B. ratti sp. nov.

Clonal growth of Blastocystis hominis in soft agar with sodium thioglycollate

The present report describes a method for establishment of colonies of Blastocystis hominis from single cells in soft agar. The percentage of colony-forming efficiency (% CFE = number of colonies grown/number of cells inoculated x 100) for the cultures was greatly improved by the addition of sodium thioglycollate. Five human Blastocystis isolates chosen for this study showed no apparent variation in colonial morphology. Isolated colonies were also successfully grown in liquid medium, providing a means of obtaining large numbers of B. hominis cells that had arisen from a single clone.

The mechanism of assimilate partitioning and carbohydrate compartmentation in fruit in relation to the quality and yield of tomato

The limitation of tomato yield was investigated in a number of cultivars with contrasting fruiting habits. Unless light is limiting, yield is mainly restricted by the number or the size of the fruit (i.e. the sink strength) rather than the supply of assimilate (i.e. the source strength). Fruit size is determined by both cell number and cell size. The rate of fruit expansion is affected by assimilate supply, temperature and water relations in the plant. The size or the growth rate of a tomato fruit is regulated by the import of assimilate and water. The sink strength for assimilate of a tomato fruit measured by the rate of assimilate import may be related to the routes of sugar transport into the sink cells during fruit development. Enzymic regulation of the hydrolysis of sucrose by sucrose synthase and the accumulation of starch by ADPG pyrophosphorylase may determine the rate of assimilate import in the young fruit. Vacuolar invertase activity may determine the sugar composition of a mature fruit, but may not affect the overall dry matter accumulation of a tomato fruit. While yield is determined by the balance between source and sink strengths of the plant, quality is determined by the transport and metabolism of sugars within the fruit.

Observations on the ultrastructure and viability of the cystic stage of Blastocystis hominis from human feces

This report describes the ultrastructure and viability of cysts of Blastocystis hominis from feces of infected patients. The cysts were round to ovoid, measured 2-5 microns in size, and contained a condensed cytoplasm that had vacuoles of varying sizes, four nuclei, and as many as six cristate mitochondria. The cell wall was rather electron-lucent. Surprisingly, chromatoid-like structures were found in the cytoplasm and nucleus of some of the cysts. These have not previously been reported in Blastocystis. The cysts can survive in water for up to 19 days at normal temperatures but are fragile at extreme temperatures and in common disinfectants.

Colony formation of Blastocystis hominis in soft agar

This is the first description of a method for growing axenized Blastocystis hominis as colonies in petri dishes containing soft agar. Blastocystis cells cultured in two types of agar appeared to show different colonial morphologies as well as differing colony yields. Microscopic examination of the colonies revealed many amoeboid and giant cells. Many cells were also shown to possess thin filament-like structures that appeared to stretch across the central vacuole.

Production and characterization of murine monoclonal antibodies to Blastocystis hominis

Several hybridomas producing antibodies detected by enzyme-linked immunosorbent assay (ELISA) were established by fusions of mouse myeloma P3.X63.Ag8.U1 with spleen cells from BALB/c mice immunized against an isolate of Blastocystis hominis. Five strongly positive hybrids (6B6, 1D5, 1E7, 4F7 and 4G11) were cloned and all were found to secrete IgM monoclonal antibodies. Four MAbs (6B6, 1E7, 4F7 and 4G11) reacted in immunoblots with a number of B. hominis antigens (mol. wt ranging from 25,000 to 220,000) which were likely to be repeating oligosaccharide epitopes located on glycoproteins, as indicated by pronase and periodate treatment. Another MAb (1D5) reacted with a single antigenic band (mol. wt 30,5000). Similar results were obtained in immunoblots using 4 other B. hominis isolates. Indirect fluorescent-antibody assay (IFA) using MAbs showed 3 patterns of reactivity. 1D5 showed patchy fluorescence, 4F7 showed peripheral fluorescence and 6B6, 1E7 and 4G11 showed bright diffuse fluorescence. These patterns were observed for all 5 human Blastocystis isolates. The MAbs exhibited some cross-reactivity with 2 reptilian Blastocystis isolates but not with Giardia intestinalis, Trichomonas vaginalis or Entamoeba histolytica.

Axenic culture of reptilian Blastocystis isolates in monophasic medium and speciation by karyotypic typing

The growth of axenic reptilian isolates of Blastocystis in Iscove's modified Dulbecco's medium (IMDM) was studied and the morphology of the parasite was examined by phase-contrast microscopy. The chromosomal patterns of these reptilian isolates of Blastocystis were examined by pulsed-field gel electrophoresis (PFGE) and compared with those of B. hominis and B. lapemi, a sea snake Blastocystis. IMDM with 10% horse serum supported excellent growth of the reptilian Blastocystis isolates. The parasites from all the isolates were predominantly vacuolar, but multivacuolar and amoeboid forms were also seen. Amoeboid forms with rather elongate pseudopodia were also observed. There were some differences in size, morphology, and growth characteristics in the different reptilian isolates. The karyotypic patterns of the Blastocystis isolates from tortoise, iguana, and python were distinctly different from one another and from those obtained with B. hominis and B. lapemi. On the basis of the above-mentioned differences in chromosomal patterns, the tortoise, iguana, and python isolates are described as new species, viz., B. geocheloni sp. nov. from Geochelone carbonaria (red-footed tortoise), B. cycluri sp. nov. from Cyclura cornuta (rhino iguana), and B. pythoni sp. nov. from Python reticulatus (reticulated python).

Serum antibodies to Trichomonas vaginalis in invasive cervical cancer patients

OBJECTIVE

To evaluate, by seroepidemiology, the possible role of the sexually-transmitted flagellate, Trichomonas vaginalis, in invasive cervical cancer.

SUBJECTS AND METHOD

Sera from 121 invasive cervical cancer patients and 242 random age-matched female controls. Antibodies to T. vaginalis were detected by the western blot technique.

RESULTS

Antibodies to T. vaginalis were detected in the sera of 41.3% (50/121) of invasive cervical cancer patients compared with only 5.0% (12/242) of female controls. All the reactive sera reacted strongly with the immunogenic surface membrane proteins of T. vaginalis of molecular weights of about 92 and 115 kDa, with variable reactivity to other immunogenic proteins of T. vaginalis.

CONCLUSION

The significantly increased relative risk, RR = 3.42 (95% CI = 1.73-6.78), is comparable to the RRs derived in seroepidemiological studies of human papillomavirus, suggesting that T. vaginalis may be even more closely associated with invasive cervical cancer than previously realized.