Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Visual Assessments of Children with Multiple Impairments: A Survey of Ophthalmologists

Children with multiple impairments often have visual impairments. This article reports on a study of the methods that 21 ophthalmologists used to assess the visual acuity of such children and the difficulties they encountered. In many cases, the information that was obtained by these methods would not be clearly understood by parents and educational and rehabilitation personnel and would not facilitate the educational management of the children. The authors describe additional means of assessing visual function and suggest alternative avenues of communicating the results.

The spectrum of fractures in the elderly

Fractures in patients aged ≥ 65 years constitute an increasing burden on health and social care and are associated with a high morbidity and mortality. There is little accurate information about the epidemiology of fractures in the elderly. We have analysed prospectively collected data on 4786 in- and out-patients who presented with a fracture over two one-year periods. Analysis shows that there are six patterns of the incidence of fractures in patients aged ≥ 65 years. In males six types of fracture increase in incidence after the age of 65 years and 11 types increase in females aged over 65 years. Five types of fracture decrease in incidence after the age of 65 years. Multiple fractures increase in incidence in both males and females aged ≥ 65 years, as do fractures related to falls.

Analysis of the incidence of fractures, together with life expectancy, shows that the probability of males and females aged ≥ 65 years having a fracture during the rest of their life is 18.5% and 52.0%, respectively. The equivalent figures for males and females aged ≥ 80 years are 13.3% and 34.8%, respectively.

Cite this article: Bone Joint J 2014;96-B:366–72.

Multiple fractures in the elderly

We present the prevalence of multiple fractures in the elderly in a single catchment population of 780 000 treated over a 12-month period and describe the mechanisms of injury, common patterns of occurrence, management, and the associated mortality rate. A total of 2335 patients, aged ≥ 65 years of age, were prospectively assessed and of these 119 patients (5.1%) presented with multiple fractures. Distal radial (odds ratio (OR) 5.1, p <  0.0001), proximal humeral (OR 2.2, p < 0.0001) and pelvic (OR 4.9, p < 0.0001) fractures were associated with an increased risk of sustaining associated fractures. Only 4.5% of patients sustained multiple fractures after a simple fall, but due to the frequency of falls in the elderly this mechanism resulted in 80.7% of all multiple fractures. Most patients required admission (> 80%), of whom 42% did not need an operation but more than half needed an increased level of care before discharge (54%). The standardised mortality rate at one year was significantly greater after sustaining multiple fractures that included fractures of the pelvis, proximal humerus or proximal femur (p < 0.001). This mortality risk increased further if patients were < 80 years of age, indicating that the existence of multiple fractures after low-energy trauma is a marker of mortality.

Accuracy of hepatocellular carcinoma detection on multidetector CT in a transplant liver population with explant liver correlation

AIM

To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for hepatocellular carcinoma (HCC) in cirrhotic patients undergoing liver transplantation. Secondary aims were to examine the effect of radiologist experience and lesion size on diagnostic accuracy.

MATERIALS AND METHODS

Thirty-nine patients (72% male with a mean age of 56.5 years) underwent liver transplantation following preoperative triple-phase MDCT examination of the liver. MDCT examinations were retrospectively independently reviewed by three radiologists for the presence and location of suspected HCCs, with the diagnostic confidence recorded using a five-point confidence scale. MDCT examinations were compared with explant specimens for histopathological correlation.

RESULTS

Histopathological results demonstrated 46 HCCs in 29 of the 39 patients. Analysis demonstrated a sensitivity of 65-75% and specificity of 47-88% for detection of HCC lesions. The sensitivity dropped to 48-57% for lesions of size ≤20mm. As the diagnostic confidence increased, there was a further decrease in the sensitivity (4-26%). The radiologist with the greatest number of years experience was found to have a significantly higher accuracy of detection of HCC lesions compared with the least experienced radiologist.

CONCLUSION

Larger lesion size of HCC and greater number of years experience of the radiologist resulted in significantly higher accuracy of HCC lesion detection. The overall sensitivity and specificity results for MDCT detection of HCC are comparable to previous helical CT imaging.

Accuracy of hepatocellular carcinoma detection on multidetector CT in a transplant liver population with explant liver correlation

AIM

To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for hepatocellular carcinoma (HCC) in cirrhotic patients undergoing liver transplantation. Secondary aims were to examine the effect of radiologist experience and lesion size on diagnostic accuracy.

MATERIALS AND METHODS

Thirty-nine patients (72% male with a mean age of 56.5 years) underwent liver transplantation following preoperative triple-phase MDCT examination of the liver. MDCT examinations were retrospectively independently reviewed by three radiologists for the presence and location of suspected HCCs, with the diagnostic confidence recorded using a five-point confidence scale. MDCT examinations were compared with explant specimens for histopathological correlation.

RESULTS

Histopathological results demonstrated 46 HCCs in 29 of the 39 patients. Analysis demonstrated a sensitivity of 65-75% and specificity of 47-88% for detection of HCC lesions. The sensitivity dropped to 48-57% for lesions of size ≤20mm. As the diagnostic confidence increased, there was a further decrease in the sensitivity (4-26%). The radiologist with the greatest number of years experience was found to have a significantly higher accuracy of detection of HCC lesions compared with the least experienced radiologist.

CONCLUSION

Larger lesion size of HCC and greater number of years experience of the radiologist resulted in significantly higher accuracy of HCC lesion detection. The overall sensitivity and specificity results for MDCT detection of HCC are comparable to previous helical CT imaging.

Mutations in the selenocysteine insertion sequence-binding protein 2 gene lead to a multisystem selenoprotein deficiency disorder in humans

Selenium, a trace element that is fundamental to human health, is incorporated into some proteins as selenocysteine (Sec), generating a family of selenoproteins. Sec incorporation is mediated by a multiprotein complex that includes Sec insertion sequence-binding protein 2 (SECISBP2; also known as SBP2). Here, we describe subjects with compound heterozygous defects in the SECISBP2 gene. These individuals have reduced synthesis of most of the 25 known human selenoproteins, resulting in a complex phenotype. Azoospermia, with failure of the latter stages of spermatogenesis, was associated with a lack of testis-enriched selenoproteins. An axial muscular dystrophy was also present, with features similar to myopathies caused by mutations in selenoprotein N (SEPN1). Cutaneous deficiencies of antioxidant selenoenzymes, increased cellular ROS, and susceptibility to ultraviolet radiation-induced oxidative damage may mediate the observed photosensitivity. Reduced levels of selenoproteins in peripheral blood cells were associated with impaired T lymphocyte proliferation, abnormal mononuclear cell cytokine secretion, and telomere shortening. Paradoxically, raised ROS in affected subjects was associated with enhanced systemic and cellular insulin sensitivity, similar to findings in mice lacking the antioxidant selenoenzyme glutathione peroxidase 1 (GPx1). Thus, mutation of SECISBP2 is associated with a multisystem disorder with defective biosynthesis of many selenoproteins, highlighting their role in diverse biological processes.

The safety profile of anti-tumour necrosis factor therapy in inflammatory bowel disease in clinical practice: analysis of 620 patient-years follow-up

BACKGROUND

Anti-TNF agents are now widely used in Crohn's disease (CD), and in ulcerative colitis (UC).

AIM

To review the safety profile of anti-TNF agents in all patients treated with infliximab in Edinburgh from 1999 to 2007.

METHODS

Complete data were available on 202/207 patients comprising 157 CD, 42 UC and three coeliac disease. Median follow-up was 2.4 years (1.0-4.9) with a total of 620 patient-years follow-up. About 19.1% of CD patients were subsequently treated with adalimumab.

RESULTS

Seven deaths (3.3%) occurred in follow-up; only one death was <1 year post-infliximab (at day 72, from lung cancer). A total of six malignancies (three haematological, three bronchogenic) and six cases of suspected demyelination (three with confirmed neurological disease) were reported. In the 90 days following infliximab, 95 adverse events (36 serious) occurred in 58/202 (28.7%) patients. In all, 42/202 (20.8%) had an infectious event (22 serious) and 27/202 (13.4%) of patients had an infusion reaction: 19 acute (four serious) and eight delayed (three serious).

CONCLUSIONS

Serious infections, malignancies and neurological disease complicate anti-TNF use in clinical practice. Although evidence for causality is unclear, potential mechanisms and predisposing factors need to be explored. In individual patients, the risk/benefit analysis needs to be carefully assessed and discussed prior to commencement of therapy.

Aortic calcification is associated with aortic stiffness and isolated systolic hypertension in healthy individuals

Arterial stiffening is an independent predictor of mortality and underlies the development of isolated systolic hypertension (ISH). A number of factors regulate stiffness, but arterial calcification is also likely to be important. We tested the hypotheses that aortic calcification is associated with aortic stiffness in healthy individuals and that patients with ISH exhibit exaggerated aortic calcification compared with controls. A total of 193 healthy, medication-free subjects (mean age+/-SD: 66+/-8 years) were recruited from the community, together with 15 patients with resistant ISH. Aortic pulse wave velocity (PWV) was measured noninvasively, and aortic calcium content was quantified from high-resolution, thoraco-lumbar computed tomography images using a volume scoring method. In healthy volunteers, calcification was positively and significantly associated with aortic PWV (r=0.6; P<0.0001) but was not related to augmentation index or brachial PWV. Calcification was significantly higher in treatment-resistant and healthy subjects with ISH compared with controls (mean [interquartile range]: 1.92 [1.14 to 3.66], 0.84 [0.35 to 1.75], and 0.19 [0.1 to 0.78] cm3, respectively; P<0.0001 for both). In a multiple regression model, aortic calcium was independently associated with aortic PWV along with age, mean arterial pressure, heart rate, and estimated glomerular filtration rate (R(2)=0.51; P<0.0001). Only age, calcium phosphate product, and aortic PWV were independently associated with calcification. These data suggest that calcification may be important in the process of aortic stiffening and the development of ISH. Calcification may underlie treatment resistance in ISH, and anticalcification strategies may present a novel therapy.

A novel gel-based method for self-collection and ambient temperature postal transport of urine for PCR detection of Chlamydia trachomatis

OBJECTIVES

The aim of this study was to develop a novel urine transport method to be used in self-collection-based screening for Chlamydia trachomatis. The method needed to be suitable for C trachomatis PCR detection, be economical and suitable for transport by standard envelope mailing.

METHODS

An anhydrous gel composed of super-absorbent polymer and buffering agent was used to desiccate urine into a dry granulous state, which could subsequently be reconstituted upon arrival at a laboratory. DNA was then extracted from the reconstituted solution using the Roche MagNA Pure protocol for the detection of C trachomatis by PCR. Collections of urine specimens from three populations with widely differing chlamydia prevalence (100%,n = 56; 47%, n = 70; 3%, n = 97) were used. We determined the gel method's impact on C trachomatis PCR sensitivity and specificity using neat and gel-processed urine specimens. An equine herpes virus PCR was used to test for assay inhibition.

RESULTS

Overall, the sensitivity of the gel-based method ranged from 94.6-100% compared with neat urine, with a specificity of 100%. No PCR inhibition or decrease in analytical sensitivity was observed using the gel-processed extracts.

CONCLUSIONS

The gel-based method was found to be suitable for the detection of C trachomatis by PCR. In addition, its ease of use, effectiveness at ambient temperature and low cost makes it well-suited for self-collection kits used in population-based C trachomatis screening, particularly for geographically and socially isolated individuals.

The use of adalimumab in the management of refractory Crohn's disease

BACKGROUND

Adalimumab is a humanized monoclonal antibody targeting tumour necrosis factor-alpha. Recent clinical trials have demonstrated its efficacy in Crohn's disease; however, experience in clinical practice remains limited.

AIM

To investigate the efficacy and safety of adalimumab in the clinical setting.

METHODS

The clinical outcomes of patients with medically refractory Crohn's disease treated with adalimumab in the Western General Hospital Edinburgh, over a 3-year period (2003-2006), were studied.

RESULTS

Twenty-two (14 females; age at therapy: 32.6 years) patients were treated using an 80/40 mg induction regimen followed by fortnightly 40 mg treatment. All had proven refractory/intolerant to corticosteroids and immunosuppression. Twenty patients had had previous infliximab infusions - of these eight (36%), six (27%), three (14%) had previous infusion reactions, no response and lost response to infliximab, respectively. Over a period of 1.0 years (IQR: 0.62-2.5), Kaplan-Meier analyses showed that 68% (seven nonresponders) were in clinical remission and 67% (five surgery - discounting oral CD) avoided further surgery for active disease. 59% required dose escalation to 40 mg weekly (0.55 years; IQR: 0.22-1.4). Three (50%) primary nonresponders to infliximab achieved remission. Two patients developed serious infective complications and one patient developed lung cancer.

CONCLUSIONS

Adalimumab is efficacious in refractory Crohn's disease, with benefit observed in infliximab primary nonresponders. However, many patients require escalation of dosing regimen.

46. INNOVATION AND DESIGN: IMPROVING CONTACT TRACING IN SEXUAL HEALTH CLINICS

Contact tracing (CT) is an integral part of sexually transmitted infection (STI) management. Although routinely conducted in most sexual health clinics (SHCs), the methods used may vary. To improve CT required novel approaches. First we audited the outcomes of current contact tracing methods. A major finding of this audit was that while CT was routinely recommended, outcomes were poorly recorded. We developed a sticker to be placed in the charts of clients with a traceable STI. This indicated the number of contacts requiring notification, and how many had been notified and treated at our clinic. This enabled a standardised approach to CT records and improved ability to audit outcomes. It also focused clinicians on the need to ensure followup of CT and to offer assistance when CT had not been done. Next, a brochure was developed to give to clients when diagnosed with a traceable STI. This brochure mentioned the reasons for contacting patterns, dispelled some myths that have been found in previous studies about telling partners and provided ideas about how to tell partners. In conjunction with this a SMS was developed, that could be sent to index cases' mobile phones, allowing them to forward the SMS to partners. This was seen as an ideal method for young people who frequently had mobile numbers of past partners but little other contact details. It was also able to be simple and quick. The next step will be reauditing the CT outcomes once the SMS and brochure are in established use.

Circulating levels of MCP-1 and eotaxin are not associated with presence of atherosclerosis or previous myocardial infarction

The chemokines are a family of signalling proteins that participate in regulation of the immune system and have been implicated in the pathogenesis of vascular diseases. Deleting the gene encoding the chemokine MCP-1 in mouse models of atherosclerosis reduces lipid lesion formation and circulating chemokines are upregulated in man immediately following myocardial infarction (MI) or coronary angioplasty. We have therefore investigated whether circulating levels of two chemokines (MCP-1 and eotaxin) differ between subjects with and without atherosclerosis. We have used three different methods of measuring the presence and extent of atherosclerosis in human subjects: duplex ultrasonography of the carotid arteries and clinical diagnosis of coronary heart disease on individuals from the general population and coronary angiography on patients with suspected heart disease. There was no difference in the levels of circulating MCP-1 or eotaxin, measured by ELISA, between subjects with and without atherosclerosis. Furthermore, any increase in circulating MCP-1 following acute MI must be short-lived, since chemokine levels were not different in subjects who had had an MI previously compared to those who had not. We conclude that although there may be a transient increase in circulating chemokine levels following coronary angioplasty, there is no difference in the levels of circulating MCP-1 or eotaxin in subjects with and without atherosclerosis.

A microtitre format assay for proline in human serum or plasma

BACKGROUND

Recent studies have suggested that low serum proline concentration may be associated with low bone mineral density. However, further investigation of this association has been hampered by the lack of a relatively high throughput assay for proline in biological fluids. Here we report a sensitive and specific microtitre plate format assay for proline which exploits the chemical interaction between proline and isatin.

METHODS

Human serum or plasma is deproteinised by incubation with sodium citrate buffer pH 4.1 at 95 degrees C, and the supernatant is reacted with isatin at 95 degrees C for 3 h. The resultant blue coloured product is quantitated sprectrophometrically.

RESULTS

This assay yields a linear standard curve in the range 15 micromol/l to 1 mmol/l (r=0.998+/-0.002; n=8 determinations) with a sensitivity of 31+/-11 micromol/l. None of the other proteogenic amino acids are detected (<0.3% detection at 10 mmol/l) and the closely related metabolite hydroxyproline is only very weakly detected (3% detection at 10 mmol/l). Using human serum, the assay has linear dilution characteristics and a mean spike recovery of 107+/-5%. Repeated re-measurement of the same serum sample yields an intra-assay coefficient of variation (CV) of 4.8% and an inter-assay CV of 6.1%.

CONCLUSIONS

This method provides the first reliable micro-titre format assay for proline in human serum.

Intraarterial cisplatin plus intravenous doxorubicin for inoperable recurrent meningiomas

The majority of meningiomas are cured by surgical resection. There is little information in the literature on the use of chemotherapy in meningiomas. We report 2 patients with inoperable recurrences of meningiomas that responded (1 patient) or stabilized (1 patient) when treated with the combination of intracarotid cisplatin plus intravenous doxorubicin.

Evidence of a direct relationship between neutrophil collagenase activity and periodontal tissue destruction in vivo: role of active enzyme in human periodontitis

To assess the temporal relationship between periodontal tissue destruction and the activity of collagenase, exudate from inflamed periodontal tissues was collected and latent and active collagenase activities were measured by a functional assay in a longitudinal cohort study. Comparisons were made between human subjects with either: 1) inflammation with a previous history of progressive loss of connective tissue and bone support (n = 14); 2) inflammation and previous history of bone loss but now clinically stable (n = 27); or 3) inflammation and no loss of bone support (n = 17). Experiments using specific enzyme inhibitors, blocking antibodies and SDS-PAGE fluorograph to identify the pattern of collagen substrate degradation demonstrated that the collagenase activity was derived from neutrophils and not from bacteria or other host cells. Active collagenase activity pooled from 6 sites per subject was respectively 5 and 6-fold higher in the group with progressive loss of connective tissue compared to the groups with either inflamed tissues alone or with inflammation and previous bone loss. In contrast, latent collagenase was increased up to 2 fold higher in the group with inflammation but no bone loss compared to the group with progressive lesions. Moreover, the ratio of active to total collagenase activity was 50% higher in the group with progressive lesions. Although in all subjects successive measurements of site-specific active collagenase 1 month apart demonstrated wide variation (r < 0.50), only in sites with progressive periodontal destruction was there significant increase of active collagenase with time (1.28 x 10(-4) collagenase units per day). There were also sharp elevations in active enzyme level at the time of detection of loss of connective tissue attachment in specific sites of 8 subjects. At the time of detection of connective tissue attachment loss, there was an overall 40% increase of pooled active collagenase activity in all subjects with progressive loss of connective tissue compared to pre-breakdown sampling times. These data provide strong in vivo evidence for a direct role of active neutrophil collagenase in the pathological destruction of periodontal connective tissue.

Comparison of the effects of cromakalim in trachea isolated from normal and albumin-sensitive guinea-pigs

The effects of the K(+)-channel activator, cromakalim, on spontaneous tone and constrictor responses to vagal stimulation or acetylcholine were compared in trachea isolated from groups of guinea-pigs that were: untreated; sensitized and chronically exposed to inhaled albumin; or sham sensitized. Responses were assessed as changes in intraluminal pressure in the isolated, Krebs-filled trachea, increases and decreases in intraluminal pressure directly reflecting constriction and dilatation, respectively. Cromakalim reduced resting intraluminal pressure in normal trachea but in sensitized trachea mixed effects occurred, many preparations exhibiting increases in intraluminal pressure, particularly at lower concentrations of cromakalim. Cromakalim attenuated the frequency-dependent increases in intraluminal pressure evoked by stimulation of the vagus nerve in a concentration-dependent manner and to a similar degree in trachea from each of the three groups tested. The degree of attenuation was similar in the absence and presence of the cyclo-oxygenase inhibitor flurbiprofen. In untreated trachea, responses to a range of concentrations of applied acetylcholine were attenuated by cromakalim. In sensitized trachea the response to the lowest concentration of applied acetylcholine was attenuated by cromakalim but responses to higher concentrations of were unaffected. The results indicate that the direct relaxant effect of cromakalim is altered in sensitized trachea, which may indicate abnormal K(+)-channel behaviour in the smooth muscle cell membrane. Attenuation by cromakalim of vagal responses occurs in both normal and sensitized trachea, due chiefly to a pre-junctional effect on cholinergic neurotransmission which is independent of the generation of cyclo-oxygenase products.

Immunogenicity and safety of PRP-T conjugate vaccine given according to the British accelerated immunisation schedule

The immunogenicity and safety of a new Haemophilus influenzae type b conjugate vaccine, PRP-T, was studied in 107 infants from the Oxford district. The vaccine was given concurrently with diphtheria, pertussis, tetanus, and polio vaccines at 2, 3, and 4 months of age. Symptoms after immunisation were recorded by a parent. Sera were obtained before the first immunisation and at 5 months of age and the antibodies were measured by both radioimmunoassay and enzyme linked immunosorbent assay (ELISA). No serious adverse reactions were observed and there was no increase in the incidence of expected minor side effects. By radioimmunoassay, the geometric mean titre of serum anticapsular antibody increased from 0.09 micrograms/ml before immunisation to 5.01 micrograms/ml after three immunisations. Ninety eight per cent of children had antibody concentrations consistent with protection (greater than or equal to 0.15 micrograms/ml). IgG antibody concentrations measured by ELISA correlated well with total antibody concentrations measured by radioimmunoassay (r = 0.864). These results provide encouragement that routine immunisation against H influenzae type b at 2, 3, and 4 months of age, could prevent most cases of disease in children in the UK.

Phase II study of oral menogaril as first line chemotherapy for advanced breast cancer: a National Cancer Institute of Canada Clinical Trials Group study

The National Cancer Institute of Canada (NCIC) Clinical Trials Group conducted a phase II study of weekly oral menogaril as first-line therapy in 51 patients with incurable, metastatic or locally advanced breast cancer. While no prior chemotherapy for metastatic disease was permitted, prior adjuvant chemotherapy was allowed provided that no anthracycline or anthracene had been given. Forty-eight patients were evaluable for response. Two patients (4%) achieved complete remissions, 9 patients (19%) achieved partial remissions, 26 patients (54%) were stable and 11 patients (23%) failed. At the initial menogaril dose of 275 mg/m2 per week, 13 of 14 patients required a dose reduction and/or a treatment delay of one or more weeks. Therefore, the menogaril dose was reduced to 225 mg/m2 per week for the last 37 patients. At that those, 20 of 37 patients developed grade 3 or 4 granulocytopenia and 22 required dosage delays. At the initial starting dose, the average dose intensity actually delivered was 169 mg/m2 per week. At 225 mg/m2 the average dose intensity actually delivered was 197 mg/m2 per week. Toxic effects included mild to moderate nausea and vomiting, diarrhea, hair loss and occasional hyperpigmentation. In summary, menogaril is an anthracycline derivative that has modest activity when administered orally to minimally pretreated patients with breast cancer.

Serial doxycycline and metronidazole in prevention of recurrent periodontitis in high-risk patients

The efficacy of metronidazole and doxycycline in preventing recurrent periodontitis was studied in 23 patients. After treatment in the previous 7 months with either bimonthly scaling and 3 weeks of systemic doxycycline (11 subjects) or scaling and placebo (12 subjects), patients were monitored for recurrent periodontitis and were scaled every 2 months. When either a periodontal abscess or greater than 2 mm loss of gingival attachment was observed, metronidazole was administered (250 mg every 8 hours) for 10 days. In the placebo plus metronidazole group, 5 patients (42%) exhibited recurrent periodontitis after the metronidazole regimen compared with only one (9%) in the doxycycline plus metronidazole group (P less than 0.096). Subgingival plaque samples at study and healthy control sites were screened for the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum by immunofluorescence and for spirochetes using Ryu's stain. Presence/absence analysis of the sum of scores of the 6 individual pathogens demonstrated large reductions (P less than 0.005) in the frequency of detection of pathogens in the former doxycycline compared with the placebo plus metronidazole group at both study and control sites before and one month after metronidazole. By 7 months after metronidazole, there was no detectable difference between groups. These results indicate that prevention of recurrent periodontitis with metronidazole may be enhanced by previous treatment with doxycycline.

Collagenase activity in recurrent periodontitis: relationship to disease progression and doxycycline therapy

Previous reports have suggested that active progression of periodontitis may be correlated with increased collagenolytic activity, and that improved clinical conditions after tetracycline treatment may be explained by inhibition of host collagenase. Eighty-two patients with a recent history of periodontal abscesses and/or loss of gingival attachment level (GAL) despite active periodontal therapy were enrolled in a double-blind, randomized, placebo-controlled trial. Clinical measurements, sampling of gingival crevicular fluid (GCF) and subgingival scaling were performed every 2 months. If any site exhibited greater than 2 mm loss of GAL or a periodontal abscess, patients were administered either 100 mg doxycycline per day for 3 weeks or placebo. During 12 months of monitoring, 55 patients exhibited recurrent active disease and were then randomly assigned to either the doxycycline (n = 30) or placebo (n = 25) groups. Analysis of active collagenase and latent collagenase in GCF samples were determined by functional assays and quantitated after SDS-PAGE and fluorography. Collagenase activities were assayed at sites exhibiting active destruction (study site), at sites with pocket depth comparable to the study site but without active destruction, and at healthy sites. Clinical measurements of GAL and collagenase activity were made at intervals between 1 wk and 7 months after completion of the drug regime. Within 7 months, 15 out of 19 patients on placebo exhibited recurrent disease compared to 13 out of 29 patients on doxycycline. Collagenase activity exhibited large variations among patients and was analyzed as presence or absence of active collagenase with a logistic model.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of calcium modulators on vagally-mediated constriction in the guinea-pig isolated trachea

1. The effects of calcium modulators on tracheal constriction evoked by vagal stimulation were examined in the isolated, innervated trachea of the guinea-pig. Responses were assessed in the Krebs-filled trachea as changes in intraluminal pressure (ILP), increases and decreases reflecting constriction and dilatation, respectively. 2. Preparations had a positive resting ILP, indicating significant spontaneous tone. Verapamil and nifedipine reduced baseline ILP, whilst Bay K 8644 had mixed effects. 3. Verapamil and nifedipine attenuated vagal responses in a concentration-dependent manner. At lower concentrations attenuation was due entirely to postjunctional effects but at higher concentrations prejunctional effects may have contributed to attenuation. 4. Verapamil and nifedipine attenuated vagal responses in the absence or presence of flurbiprofen, indicating that their effects are largely independent of the generation of cyclo-oxygenase products. Nifedipine, however, was less effective in reducing responses to low frequency vagal stimulation (up to 5 Hz) when flurbiprofen was present. 5. Bay K 8644 augmented vagal responses, the degree varying widely between preparations. 6. It was concluded that influx of Ca2+ through voltage-operated Ca2+ channels contributes significantly to vagally-mediated tracheal constriction in normal trachea and in trachea where endogenous release of cyclo-oxygenase products is inhibited.

A randomized, placebo-controlled trial of doxycycline: effect on the microflora of recurrent periodontitis lesions in high risk patients

Twenty-seven patients with a recent history of periodontal abscesses and/or loss of gingival attachment level (GAL) despite active periodontal therapy were enrolled in a double-blind, randomized, placebo-controlled trial. Clinical measurements and subgingival scaling were performed every 2 months. When a site exhibited greater than or equal to 2 mm loss of GAL or a periodontal abscess, patients were administered either doxycycline at a dosage of 200 mg to start and 100 mg per day for 3 weeks, or a placebo. Clinical measurements of GAL and microbial analysis of subgingival plaque at study and control sites were made at the time of active disease and at intervals of 1 week and 7 months after completion of the drug regime. Plaque samples were screened for the presence of Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Bacteroides intermedius (Bi), Eikenella corrodens (Ec) and Fusobacterium nucleatum (Fn) by indirect immunofluorescence antibody technique and for spirochetes (Sp) using Ryu's stain. Based on presence or absence analysis of the sum scores of the 6 pathogens, both the placebo (n = 10) and the doxycycline groups (n = 17) exhibited similar scores at the time of detection of active disease (mean placebo = 2.38 +/- 0.32; mean doxycycline = 2.95 +/- 0.27; P = 0.18). One week after treatment, the probability of detection was unchanged in the placebo group (mean placebo = 3.14 +/- 0.47), but was significantly reduced in the doxycycline group (mean doxycycline = 1.77 +/- 0.26; P = 0.0002). Study (active) sites exhibited scores 2 to 3 times higher than control (inactive) sites before doxycycline treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Randomized controlled trial of doxycycline in prevention of recurrent periodontitis in high-risk patients: antimicrobial activity and collagenase inhibition

82 patients with a recent history of periodontal abscesses and/or loss of gingival attachment (GAL) despite active periodontal therapy were enrolled in a double-blind, randomized, placebo-controlled trial. Clinical measurements and subgingival scaling were performed every 2 months. If any site exhibited greater than or equal to 2 mm loss of GAL or a periodontal abscess, patients were administered either 100 mg Doxycycline per day for 3 weeks or placebo. During 12 months of monitoring, 55 patients exhibited recurrent active disease and were then randomly assigned to either the Doxycycline or placebo groups. Clinical measurements of GAL and microbiological culture of subgingival bacteria were made at intervals between 1 week and 7 months after completion of the drug regime. Within 7 months, 15 out of 19 patients on placebo exhibited recurrent disease compared to 13 out of 29 patients on Doxycycline, a relative risk reduction of 43% (p less than 0.05) for Doxycycline compared to placebo. Minimal inhibitory concentrations of Doxycycline for subgingival plaque samples from active sites ranged between 25-100 micrograms/ml, which are several fold higher than reported crevicular fluid concentrations for this drug. However gingival crevicular fluid collagenase was inhibited in vitro at concentrations of 5-10 micrograms/ml Doxycycline. These data indicate that Doxycycline provides significant risk reduction of recurrent periodontitis in patients with active disease.

Variation of breath sound and airway caliber induced by histamine challenge

Inspiratory breath sounds were recorded from the chest wall during histamine challenge in five subjects with mild asthma (baseline FEV1 greater than 60% of predicted normal). The median frequency of the power spectrum of the breath sounds was found to correlate with the percentage change in FEV1 induced by histamine and with FEF50. The analysis suggests that for a decrease in FEV1 of 20%, the median frequency of breath sound would increase by 80 Hz. Variation in airway caliber produced a consistent alteration in the distribution of energy in inspiratory breath sound in the absence of wheeze. Spectral analysis of breath sound may be a useful addition to conventional spirometry in identifying changes in airway diameter.

Measuring free thyroxin by using magnetic antibody-containing microcapsules

We describe a novel magnetic-separation microencapsulated antibody displacement assay for free thyroxin. The method is rapid (results available in just over an hour), with a detection limit of 3 pmol/L, and an interassay precision of less than 10% over the range 8-75 pmol/L. Results are not influenced by changes in the concentration of thyroxin-binding globulin or albumin, nor by the presence of circulating anti-thyroxin antibodies or physiological concentrations of nonesterified (free) fatty acids. A reference interval of 8.4-18.4 pmol/L was established for a large euthyroid adult population. Patients with various nonthyroidal illnesses exhibited a similar reference interval (6.2-17.4 pmol/L). Results from pregnant women, at all stages of gestation, were within the nonpregnant euthyroid reference interval. Complete discrimination was obtained between the euthyroid reference interval and values from patients with untreated thyrotoxicosis (24-75 pmol/L). Excellent, though incomplete, discrimination was obtained for patients with untreated hypothyroidism (less than 3.0-9.0 pmol/L). Results for a group of patients defined as having compensated euthyroidism (5.0-15 pmol/L) showed considerable overlap with the euthyroid reference interval. Patients taking thyroxin, who were clinically euthyroid and whose serum concentration of thyrotropin was within its euthyroid reference interval, had free thyroxin concentrations in the range 13.4-24.2 pmol/L. We discuss the validity of this assay in clinical practice.

Measuring free thyroxin by using magnetic antibody-containing microcapsules

We describe a novel magnetic-separation microencapsulated antibody displacement assay for free thyroxin. The method is rapid (results available in just over an hour), with a detection limit of 3 pmol/L, and an interassay precision of less than 10% over the range 8-75 pmol/L. Results are not influenced by changes in the concentration of thyroxin-binding globulin or albumin, nor by the presence of circulating anti-thyroxin antibodies or physiological concentrations of nonesterified (free) fatty acids. A reference interval of 8.4-18.4 pmol/L was established for a large euthyroid adult population. Patients with various nonthyroidal illnesses exhibited a similar reference interval (6.2-17.4 pmol/L). Results from pregnant women, at all stages of gestation, were within the nonpregnant euthyroid reference interval. Complete discrimination was obtained between the euthyroid reference interval and values from patients with untreated thyrotoxicosis (24-75 pmol/L). Excellent, though incomplete, discrimination was obtained for patients with untreated hypothyroidism (less than 3.0-9.0 pmol/L). Results for a group of patients defined as having compensated euthyroidism (5.0-15 pmol/L) showed considerable overlap with the euthyroid reference interval. Patients taking thyroxin, who were clinically euthyroid and whose serum concentration of thyrotropin was within its euthyroid reference interval, had free thyroxin concentrations in the range 13.4-24.2 pmol/L. We discuss the validity of this assay in clinical practice.

Intraarterial cisplatin and concurrent radiation for locally advanced bladder cancer

Between 1983 and 1987 25 patients with invasive bladder cancer (16 stage tumor 3 (T3) and nine stage T4) were treated with intraarterial cisplatin and concurrent radical radiation (20/25) or intraarterial cisplatin, concurrent preoperative radiation, and cystectomy (5/25). One patient died from treatment-related toxicity. Other toxicities have been what one would expect from the individual treatment modalities except for a sensory sacral root neuropathy in 11 of 24 (46%) patients. Twenty-three of 24 (96%) patients achieved a complete response (CR) and the projected actuarial 2-year survival is 90%. Only one of the 23 complete responders has had an invasive local recurrence. The excellent complete local response and survival rates achieved warrant further study of the combination of intraarterial cisplatin and radiation as a bladder-preserving strategy.

Assay of mitogen-induced effects on cellular incorporation of precursors for scavenger, de novo, and net DNA synthesis

In summary we have presented data on [3H]dThd incorporation into DNA for a positive and negative growth modulator. These data clearly do not correspond to those based on net DNA synthesis (ortho[32P]phosphate incorporation into purified DNA) and previous knowledge of the effects of these hormones on cell number and cellular DNA accumulation. The paradox was resolved by directly analyzing effects of hormones on de novo pyrimidine biosynthesis. E2 stimulated both de novo and scavenger pathways in the first wave of DNA synthesis and only de novo in the second (and subsequent) waves. In contrast, tam progressively inhibited de novo pyrimidine biosynthesis. These hormonal effects on intracellulr pyrimidine pool sizes rendered [3H]dThd incorporation data by itself uninterpretable. [3H]dThd is a useful measure of DNA synthesis only if verified by independent measures of net DNA synthesis for the same time course and treatment conditions. In addition it may prove beneficial in various experimental systems to develop direct assays of de novo pyrimidine biosynthesis to assess mitogen effects. The experiments presented may also prove to be useful in evaluating the effects of mitogens and antimitogens on cells synchronized in the cell cycle by any of a variety of means.

Poor prognosis metastatic gestational trophoblastic disease: experience with moderate dose methotrexate plus folinic acid rescue as initial therapy

From 1971 to 1981, twenty patients with poor-prognosis metastatic gestational trophoblastic neoplasia (GTN) were treated with moderate-dose methotrexate (1 g) and folinic-acid rescue (MD-MTX-FAR) as initial therapy. Seven (35%) were cured with MD-MTX-FAR, and salvage chemotherapy was successful in an additional seven, for a total cure rate of 70%. The ultimate outcome is similar to that reported for MAC triple therapy during this era. Hematologic and mucosal toxicity were negligible and no serious complications were encountered. We now use combination chemotherapy in patients with poor-prognosis GTN as first-line treatment. However, these results suggest that there may be advantages to the incorporation of MD-MTX-FAR in combination regimens in place of low-dose methotrexate, because of reduced toxicity and potential benefits for the prophylaxis and treatment of cerebral metastases.

Influence of cell proliferation and cell cycle phase on expression of estrogen receptor in MCF-7 breast cancer cells

In the present study, the effects of cell cycle phase and proliferation rate on the expression of specific estrogen binding activity were explored in hormone-dependent human breast cancer cells. A technique was developed to alter the proliferative rate of MCF-7 cells by plating at different densities. The doubling time ranged from 20 to 48 hr, showing a negative relation to the number of plated cells. Slowly proliferating cells had accumulated more than twice as much estrogen receptor (ER) activity as did fast-proliferating cells. Exposure of exponentially growing cells to isoleucine-deficient medium resulted in decreased thymidine incorporation and disappearance of detectable cellular ER activity. Overall protein synthesis was reduced by only 30% in cells growing in isoleucine-free medium. At 24 hr after release from isoleucine deprivation, ER levels are fully restored, although thymidine incorporation does not resume for an additional 6 to 8 hr, and increases in cell number are not seen for 24 hr. Exposure of exponentially growing cells to 2 mM thymidine for 24 hr produced partially synchronized MCF-7 cells (approximately 70%). Six hr after release from excess thymidine, cells reached S phase; after 9 hr, G2; and after 18 hr, G1. ER levels immediately and, 6 hr after release, remained unchanged, showed a slight increase at 9 hr, and showed an increase of about 50 to 60% at 18 hr. These data suggest that: (a) ER binding activity and DNA synthesis can be dissociated; (b) ongoing protein synthesis is necessary for maintenance of cellular ER activity; and (c) ER is apparently synthesized throughout the cell cycle, with some evidence that this is predominantly in G1 and G2.

Developmental aspects of sensory substitution

Research involving the provision of an artificial intersensory substitute--the SonicguideTM--is reported. Subjects were congenitally blind infants and young children. In a search task requiring distally appropriate responses, results indicated that younger subjects showed a more rapid sensitivity to the spatial information provided by the device. The implications of these developmental differences for intersensory substitutability are discussed.

Purification and properties of estrogen-responsive cytoplasmic thymidine kinase from human breast cancer

The effect of 17 beta-estradiol on cytoplasmic thymidine kinase activity was studied in MCF-7, a human breast cancer cell line in culture which responds to estrogens with an increase in the rate of growth. Levels of 17 beta-estradiol which maximally stimulate [3H]thymidine incorporation into DNA also maximally stimulate thymidine kinase activity. The Vmax for thymidine increased while the Km was not affected by estrogen stimulation when performed on nonpurified enzyme. Tamoxifen, an antiestrogen, decreased the specific activity of the enzyme. To further study its hormonal regulation, cytoplasmic thymidine kinase was purified greater than 2000-fold by affinity column chromatography. The purified preparation migrated in one band to a pI of 8.5 on an isoelectric focusing gel. The purified thymidine kinase was further characterized by examining its molecular weight, pH optimum, heat stability, utilization of phosphate donors, inhibition by nucleotides, and the effect of pyrimidine nucleoside analogs.

Immune status of children with and without severe infection during remission of malignant disease

The immune status of children with malignant disease in remission was assessed usingvarious immune function tests. Children with infections had significantlymore neutropenia, hypogammaglobulinaemia, and impaired cell-mediated immune responses than those without. These two groups combined had much more absolute lymphopenia and impairment of both cell-mediated immunity and antibody-producing capacity thancontrol children with non-malignant conditions. Regular immunological evaluation isrecommended for children with malignant disease when new intensive treatment schedules are under trial and for individual patients particularly prone to develop infections during treatment.