Ultrasonic "hole sign": a reliable sign of perforation of the gallbladder?
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Biomedical subjects
Publications and source records attributed to S Chan.
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Sixty patients with advanced breast cancer unresponsive to tamoxifen have been randomised to receive four course of mitozantrone, 14 mg m-2 (n = 30) intravenously every 3 weeks (9 weeks total) or megesterol acetate, 160 mg bd (n = 30). One in three patients (11 from each group) had substantial disease control for a minimum period of 6 months i.e., lack of progression; seven patients (23%) showed objective response to mitozantrone compared to four (13%) receiving megesterol. Non-progressive disease occurred in all sites, including visceral metastases and receptor negative patients. There were no significant differences between treatment groups in the median time (5 months each) to disease progression response duration or survival (13 months megesterol, 11 months mitozantrone) from commencing second-line therapy. Toxicity was considerably higher in the mitozantrone group. Second-line hormonal therapies can produce similar therapeutic results as those achieved from a short course of a 'short option' single agent cytotoxic in patients who were previously thought hormone insensitive. Provided that the patient does not have life threatening disease a trial of megesterol acetate is worth consideration in that it does not prejudice subsequent response to combination cytotoxic chemotherapy.
Plasma viscosity (PV), apparent whole blood viscosity (WBV), relative blood viscosity (RV) and erythrocyte deformability (filterability) (EDF) were determined in 13 New Zealand White (NZW) rabbits with alloxan induced-diabetes (AID) and 8 normal NZW rabbits, matched for age, sex and weight. AID rabbits were divided into two groups depending on the duration of hyperglycemia (long-term, greater than 6.0 months (n = 7), and short-term, less than or equal to 3.0 months of hyperglycemia, n = 6). Comparing long-term AID rabbits to normal animals, we found significant increases in WBV (P less than 0.001, 0.005 for high and low rates of shear, respectively), and a marked reduction in EDF (P less than 0.001). There was no significant difference in PV between long-term AID and normal rabbits. Conversely, PV was significantly increased in rabbits with short-term diabetes (P less than 0.01) while there was a concurrent significant increase in WBV measured at high and low rates of shear (P less than 0.001, 0.001, respectively). No difference was detected in EDF between normal and short-term AID rabbits. Furthermore, in long-term AID rabbits there was a strongly positive correlation between RV and reduced erythrocyte deformability (r = 0.94, P = 0.006) while WBV strongly correlated with PV (r = 0.92, P = 0.004) in the short-term AID subgroup. We conclude from these data: (1) elevated blood viscosity in long term AID rabbits is associated with reduced erythrocyte filterability; and (2) elevated WBV in short-term AID rabbits is associated with increased PV.
Preprandial and postprandial colonic motility and transit (scintigraphy), with respect to the splenic flexure, were studied in 10 patients with ulcerative colitis and in 9 healthy subjects. The healthy subjects had a postprandial increase in intraluminal pressure that was significantly (P less than 0.03) greater in the descending colon than in other regions of the colon. In ulcerative colitis, the pressure was decreased in all regions compared with healthy subjects, with no significant pressure gradient among different regions. In normal subjects, transit was quiescent during fasting; eating stimulated both antegrade and retrograde transit. In ulcerative colitis, transit was variable before as well as after the meal. Both healthy subjects and patients with ulcerative colitis had more rapid emptying from the splenic flexure into the sigmoid than into the transverse colon. More frequent, low-amplitude, postprandial propagating contractions occurred in ulcerative colitis (P less than 0.05) than in healthy subjects. Propagating contractions were always antegrade and caused a rapid movement of the tracer into the sigmoid. In conclusion, ulcerative colitis is characterized by (a) decreased contractility, (b) increased low-amplitude propagating contractions, and (c) variable transit. These disturbances may accentuate the diarrhea in ulcerative colitis.
The APACHE II system has been shown to be a reliable and useful means of evaluating patient outcome from the intensive care unit when applied to a broad spectrum of diagnoses. The major purpose of this study was to determine the use of APACHE II as a means of predicting outcome of ICU oncology patients. Data were retrospectively collected for 451 ICU oncology admissions. A direct relationship between severity of physiologic derangement and patient risk of death was demonstrated. Patients with scores of 30 or greater had hospital mortality rates of 100% for postoperative and 92.6% for nonoperative patients. The APACHE II was a useful means of predicting the outcome of ICU oncology patients. This potentially provides the patient, family, and physician an objective dimension in making decisions whether to transfer the oncology patient.
From 1985 to April 1990, 78 clinical dynamic cardiomyoplasty procedures were performed using the latissimus dorsi muscle stimulated with the Medtronic Cardiomyoplasty System. Indications for surgery were mostly ischemic and idiopathic dilated cardiomyopathies with patients in severe cardiac insufficiency (NYHA Class III and IV). Results of this multicenter study (11 centers) indicate that the dynamic cardiomyoplasty procedure can be transferred and reproduced in many centers with low perioperative mortality and that it improves the functional status of patients who survive the procedure. The survival rate suggests a long-term benefit (average implant time: 11.7 months). Although clinical functional improvement was reported, actual hemodynamic augmentations could not be clearly demonstrated under the protocol. Further studies of functional and hemodynamic parameters are necessary to determine if dynamic cardiomyoplasty is efficacious for a well-defined group of congestive heart failure patients. These points will be addressed in forthcoming studies.
The role of human papillomavirus (HPV) proteins in the pathogenesis of cervical intra-epithelial neoplasia (CIN) and invasive cervical cancer is poorly understood. To characterize E4 protein expression in 49 paraffin-embedded cervical biopsies representing different histopathologic grades of disease, antibodies were elicited to a synthetic peptide corresponding to amino acids 20-34 of a protein predicted to be encoded by the HPV 16 E4 open reading frame. The E4 protein was detected throughout the spectrum of CIN, from CIN1 to CIN3. Expression was localized to the cell nucleus, primarily in the superficial layers of the squamous cervical epithelium. Ultrastructural studies showed that the E4 protein was organized into compact, intranuclear arrays 25-35 nm in diameter. E4 protein expression was also demonstrated in some histologically normal tissues containing HPV 16 DNA, but not in any of five cervical cancers containing HPV 16 DNA. These results suggest that E4 protein expression may precede development of light microscopic tissue abnormalities, that it may continue through the spectrum of CIN, and that expression of this protein may be reduced or terminated in invasive cancer. The function of this protein remains unknown, but its nuclear localization may be consistent with a role in viral maturation.
The effects of prostaglandin E2 (PGE2) were histomorphometrically evaluated in cancellous bone of the axial skeleton of ovariectomized, osteopenic rats. Four months following bilateral ovariectomy (OVX) and sham-ovariectomy (SHAM) at 3 months of age, rats received daily subcutaneous injections of PGE2 at 0, 0.3, 1.0, 3.0 and 6.0 mg/kg/day for 30 days. The undecalcified fourth lumbar vertebral bodies (LVB) were processed for static and dynamic bone histomorphometry. The OVX rats possessed a slightly osteopenic LVB (17% vs. 24% cancellous bone mass). In rats given PGE2 at 3 and 6 mg/kg/day for 30 days, bone turnover, lamellar bone mass, and formation of new woven bone trabeculae were increased. Observations supported the conclusion that PGE2 activates bone modeling and remodeling, and shifts bone balance in favor of formation. In OVX rats given 6 mg PGE2/kg/day, cancellous bone mass and trabecular numbers were restored to levels found in untreated SHAM rats. Cancellous bone mass in the LVB of SHAM rats given 3 and 6 mg PGE2/kg/day increased by 16% and 30% over that of control rats. In addition, PGE2 stimulated longitudinal bone growth in both OVX and SHAM rats, a response that differed from male rats.
To assess the efficacy of prostaglandin E2 (PGE2) in augmenting cortical bone mass, graded doses of PGE2 were subcutaneously administered for 30 days to seven-month old sham-ovariectomized (SHAM) and ovariectomized (OVX) rats. Both groups were operated at three months of age. Histomorphometric analyses of double fluorescent labeled tibial shafts were performed on basal control, OVX, and SHAM rats treated with 0, 0.3, 1, 3, and 6 mg PGE2/kg/d for 30 days. Baseline aging data showed increased cortical tissue and cortical bone area and reduced bone formation parameters at the periosteal and endocortical bone envelopes between three and eight months of age. The tibial shafts of OVX rats compared to SHAM controls showed elevated periosteal mineral apposition rate and endocortical bone formation parameters. PGE2 administration to OVX and SHAM rats increased cortical bone by the addition of new circumferential bone on the endocortical and periosteal surfaces, as well as woven cancellous bone in the marrow region. Stimulated osteoblastic recruitment and activity enhanced bone formation at all bone surfaces. The new bone was both lamellar and woven in nature. PGE2 treatment also activated intracortical bone remodeling (not seen in untreated eight-month old rats), creating a porous cortex. Thus, PGE2 administration activated cortical bone modeling in the formation mode (A----F), as well as intracortical bone remodeling (A----R----F). PGE2 administration to OVX rats resulted in more intracortical bone remodeling, periosteal bone formation, and new cancellous bone production than observed in PGE2 treated controls. The findings that PGE2 administration to OVX and intact female rats increases cortical bone mass, coupled with observations that mouse, rat, dog, and man respond similarly to PGE2, suggest that PGE2 administration may be useful in the prevention and treatment of postmenopausal osteoporosis.
Percutaneous nephrostomies (PCN) were performed in 25 patients with uterine cervical malignancy between November 1982 and December 1987 at the Christie Hospital and Holt Radium Institute. Group 1 consisted of eight patients with untreated disease; group 2 consisted of eight cases with recurrent tumour; and group 3 consisted of nine patients with obstructive uropathy related to previous treatment. Six patients in group 1 subsequently received radical radiotherapy, and two of them were alive and disease free (33%) ten months later. Further active treatment was only possible in two of the patients with recurrence and overall median survival was only 51 days. All patients in group 3 had normalization of their renal function post-nephrostomy and prior to definitive management of the obstruction. We conclude that the technique should be considered in patients who had no previous treatment and in patients with treatment-related complications. Its value in recurrent disease is limited.
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Aluminum has been implicated as a contributing factor to dialysis encephalopathy syndrome (DES) and osteomalacic osteodystrophy. Monitoring of its level together with i-PTH, desferoxamine infusion test, or bone biopsy gives the degree of intoxication. Specimens for aluminum must be collected in containers washed in nitric acid or disodium EDTA to avoid contamination. Determination is made with flameless atomic absorption spectrometry or neutron activation. Various experimental conditions for the former together with discussion on their merits and shortcomings are given. Included are protein precipitation, matrix modification, background correction, and sampling technique.
A study of medication compliance, side effects, and clinical change with the use of antidepressants in 32 Southeast Asian refugee patients seen at an urban mental health center is reported. Patients met criteria for either major depressive episode, posttraumatic stress disorder, or both. Only five of the 32 patients who stated that they were taking their medications regularly had antidepressant blood levels in the therapeutic range. Another 10 patients had subtherapeutic levels and the remaining 17 had undetectable blood levels. Patients with therapeutic blood levels had fewer side effects (p = 0.049) than patients with undetectable blood levels. Blood levels tended (p = 0.070) to be correlated with clinical improvement. The authors discuss cultural attitudes of Southeast Asian refugee patients toward medication use and side effects that appear to influence medication compliance.
We have identified and purified a novel cytokine, NK cell stimulatory factor (NKSF), from the cell-free supernatant fluid of the phorbol diester-induced EBV-transformed human B lymphoblastoid cell line RPMI 8866. NKSF activity is mostly associated to a 70-kD anionic glycoprotein. The purified 70-kD protein, isolated from an SDS-PAGE gel, yields upon reduction two small species of molecular masses of 40 and 35 kD, suggesting that this cytokine is a heterodimer. When added to human PBL, purified NKSF preparations induce IFN-gamma production and synergize with rIL-2 in this activity, augment the NK cell-mediated cytotoxicity of PBL preparations against both NK-sensitive and NK-resistant target cell lines, and enhance the mitogenic response of T cells to mitogenic lectins and phorbol diesters. The three activities remain associated through different purification steps resulting in a 9,200-fold purification, and purified NKSF mediates the three biological activities at concentrations in the range of 0.1-10 pM. These data strongly suggest that the same molecule mediates these three activities, although the presence of traces of contaminant peptides even in the most purified NKSF preparations does not allow us to exclude the possibility that distinct biologically active molecules have been co-purified. The absence of other known cytokines in the purified NKSF preparations, the unusual molecular conformation of NKSF, the high specific activity of the purified protein, and the spectrum of biological activities distinguish NKSF from other previously described cytokines.
A highly enriched preparation of basolateral membrane vesicles was isolated from rabbit distal colon surface epithelial cells employing the method described by Wiener, Turnheim and van Os (Weiner, H., Turnheim, K., van Os, C.H. (1989) J. Membrane Biol. 110:147-162) and incorporated into planar lipid bilayers. With very few exceptions, the channel activity observed was that of a high conductance. Ca2+-activated K+ channel. This channel is highly selective for K+ over Na+ and Cl-, displays voltage-gating similar to "maxi" K(Ca) channels found in other cell membranes, and kinetic analyses are consistent with the notion that K+ diffusion through the channel involves either the binding of a single K+ ion to a site within the channel or "single-filing" ("multi-ion occupancy"). Channel activity is inhibited by the venom from the scorpion Leiurus quinquestriatus, Ba2+, quinine, and trifluoperazine. The possible role of this channel in the function of these cells is discussed.
The authors report on 404 Southeast Asian refugees seen at a community clinic. Approximately three-quarters of these patients met DSM-III criteria for major depressive episode, and 14% had posttraumatic stress disorder. Complaints of pain and sleep disturbances were the predominant presenting symptoms. Most of the men were married, but more than 40% of the women were widowed. Between 15% and 30% of the patients reported specific traumatic experiences either in their homeland or during their escape. Widowhood and such traumatic experiences were positively correlated with more symptoms of depression and anxiety.
A comparative analysis of new cases seen at the Child Psychiatric Clinic in 1975 and 1985 is made in this study. There was a three and a half fold increase in the number of patients seen from 245 to 893. There was no significant change in sex ratio or ethnic groups. However, in 1985 more younger children (aged less than 6 years) were seen at the Clinic. The waiting time remained short with half the number of cases seen within one week of appointment. The commonest conditions besides Normal Variation were Adjustment Reaction, Mental Retardation, Conduct Disorder and Neurosis. Three-fifths of cases were discharged from follow-up within three months of therapy. Most cases (90%) did not require pharmacological therapy whilst family therapy was prescribed for a fifth of cases seen in 1985.
Radioimmunoassay (RIA) is generally used to measure certain salivary hormones because of its high sensitivity. For speed and simplicity, it has been used in the form of "direct" assays, i.e., without first extracting the analyte from its matrix. Investigating the effect of the principal salivary proteins on the binding behavior of three commercial RIA kits, we found that the Amerlex-M [125I]progesterone binding was greatly reduced when alpha-amylase and mucins were added to the binding medium, whereas IgA and IgG were less effective. The Serono Biodata [125I]testosterone binding was unaffected by proteins, while the Amerlex [125I]cortisol binding was decreased by alpha-amylase and mucins. The protein influence was largely eliminated when an extraction step was incorporated. Thus, direct RIA of saliva may be subject to matrix effects, to extents that vary with the kit and that may adversely affect the quality of the assay results.