Rapid plastic embedding is compatible with colorimetric detection following whole mount in situ hybridization in plant specimens

In performing in situ hybridizations, nonisotopic nucleic acid labeling coupled with colorimetric detection offers a safer, easier and more rapid alternative to using radioactively labeled nucleic acid probes and microscopic autoradiography. Whole mount in situ hybridization is also advantageous, because many samples can be processed identically and the reduced handling of specimens greatly reduces the risk of exposing tissues to RNase(s). The thickness of whole mount specimens, however, often prevents accurate determination of sites of expression within specific tissues. Although post-hybridization embedding and sectioning is a solution to this problem, the precipitate formed following the common colorimetric detection procedure is soluble in the organic solvents used for dehydration prior to embedding. We have developed a dehydration and embedding procedure that takes advantage of the compatibility of L.R. White resin containing 10% (v/v) polyethylene glycol 400, and heat polymerized. The addition of the plasticizer allows L.R. White embedded tissues to be sectioned at 10 microm providing excellent signal contrast.

Congenital lobar emphysema occurring in twins

Twins born with congenital lobar emphysema are reported. This has not previously been described. Diagnosis, surgical management and subsequent course is high-lighted. These twins may well be the smallest to have operative treatment.

Pleural effusions in patients with AIDS

OBJECTIVE

To describe the range of pathology causing pleural effusions in HIV infected patients with acute respiratory episodes and to attempt to identify whether any associated radiological abnormalities enabled aetiological discrimination.

METHODS

Prospective study of chest radiographs of 58 consecutive HIV infected patients with pleural effusion and their microbiological, cytological, and histopathological diagnoses.

RESULTS

A specific diagnosis was made in all cases. Diagnoses were Kaposi's sarcoma, 19 patients; para-pneumonic effusion, 16 patients; tuberculosis, eight patients; Pneumocystis carinii pneumonia, six patients; lymphoma, four patients; pulmonary embolus, two patients; and heart failure, aspergillus/leishmaniasis, and Cryptococcus neoformans, one case each. Most effusions (50/58) were small. Bilateral effusions were commoner in Kaposi's sarcoma (12/19) and lymphoma (3/4) than in para-pneumonic effusion (3/16). Concomitant interstitial parenchymal shadowing did not aid discrimination. A combination of bilateral effusions, focal air space consolidation, intrapulmonary nodules, and/or hilar lymphadenopathy suggests Kaposi's sarcoma. Unilateral effusion with focal air space consolidation suggests para-pneumonic effusion if intrapulmonary nodules are absent: if miliary nodules and/or mediastinal lymphadenopathy are detected, this suggests tuberculosis.

CONCLUSIONS

A wide variety of infectious and malignant conditions cause pleural effusions in HIV infected patients, the most common cause in this group was Kaposi's sarcoma. The presence of additional radiological abnormalities such as focal air space consolidation, intrapulmonary nodules, and mediastinal lymphadenopathy aids aetiological discrimination.

Design and validation of a machine for reproducible precision insertion of femoral hip prostheses for preclinical testing

Preclinical testing of orthopaedic implants is becoming increasingly important to eliminate inferior designs before animal experiments or clinical trials are begun. Preclinical tests can include both laboratory bench tests and computational modeling. One problem with bench tests is that variability in prosthesis insertion can significantly influence the failure rate; this makes comparison of prostheses more difficult. To solve this problem an insertion method is required that is both accurate and reproducible. In this work, a general approach to the insertion of hip prostheses into femoral bones is proposed based on physically replicating an insertion path determined using computer animation. As a first step, the seated prosthesis position is determined from templates and femur radiographs. Three-dimensional images of the prosthesis and bone are then imported into computer animation software and an insertion path in the coronal plane is determined. The insertion path is used to determine the profile of a cam. By attaching the prosthesis to a carriage, which is pneumatically moved along this cam, the required insertion motion of the prosthesis in the coronal plane can be achieved. This paper describes the design and validation of the insertion machine. For the validation study, a nonsymmetric hip prosthesis design (Lubinus SPII, Waldemar Link, Germany) is used. It is shown that the insertion machine has sufficient accuracy and reproducibility for preclinical mechanical testing.

Women's experience of maternal serum screening

OBJECTIVE

To explore the ideas, opinions, feelings, and experiences of women regarding prenatal genetic screening, specifically maternal serum screening (MSS).

DESIGN

Qualitative technique of focus groups.

SETTING

Northern, rural, inner-city, urban, and suburban communities in Ontario.

PARTICIPANTS

Women who had given birth to babies from January 1994 to May 1996, but who were not currently pregnant (n = 60).

METHOD

Six focus groups composed of women living in various communities who had recently given birth to babies explored the experience of MSS.

MAIN FINDINGS

Women want informed choice about prenatal genetic screening. Three factors influenced women's decisions to undergo or decline prenatal genetic screening: their personal values, including their philosophy of life, moral, and religious values, and attitudes regarding Down syndrome and disability; social support including their partners, families, and friends; and quality of information from health care providers. Women want their providers to give them information personally; they want to receive the information as early as possible in prenatal care to allow time for reflection; and they want unbiased, accurate information in order to make a decision that is in keeping with their personal values and beliefs.

CONCLUSIONS

Knowledge of women's ideas, opinions, feelings, and experiences regarding MSS suggests specific ways health care providers can facilitate informed decision making in prenatal screening. Providing information about genetic testing needs to be individualized, with women actively participating in the decision-making process. Information needs described by these women could apply to other prenatal genetic tests that might be available in the future.

Family physicians in maternity care. Still in the game? Report from the CFPC's Janus Project

OBJECTIVE

To describe family doctors' contribution to maternity care in Canada and to observe the influence of age, sex, region of the country, and practice population on provision of maternity care.

DESIGN

SURVEY

College of Family Physicians of Canada's Janus Project national family physician survey.

SETTING

All 10 provinces and two territories.

PARTICIPANTS

Random sample of family physicians and general practitioners, both members and non-members of the College.

MAIN OUTCOME MEASURES

Proportion of family doctors participating in prenatal, intrapartum, postpartum, and newborn care, and proportion of doctors involved in intrapartum care by age, sex, location in Canada, and practice population.

RESULTS

Overall response rate was 58%. Just over 50% of all family doctors in Canada are involved in some aspect of maternity care; 19% do intrapartum care; and 33% are involved in prenatal (shared) care. Similar proportions of men and women still do intrapartum care, but women care for more pregnancies than men. More family doctors serving rural areas are doing intrapartum care compared with doctors in urban areas, although those in urban areas tend to do more deliveries. The western provinces have the highest percentages of intrapartum caregivers. A gradual decline in percentage of intrapartum caregivers by age group increases among the 55- to 64-year-old cohort. Almost a quarter of women doctors younger than 35 years are doing intrapartum care. Most physicians doing prenatal (shared) care look after women until the third trimester.

CONCLUSIONS

Family doctors are still providing a large proportion of maternity care in Canada. This contribution must be nurtured by the College through its Maternity and Newborn Care Committee and other contacts to encourage family doctors to continue offering this essential service to childbearing women in Canada.

Parenteral ivermectin in Strongyloides hyperinfection

Strongyloides hyperinfection, unresponsive to oral ivermectin and oral albendazole, was controlled by subcutaneous administration of a veterinary preparation of ivermectin.

Going the distance: the influence of practice location on the Ontario Maternal Serum Screening Program

BACKGROUND

The Ontario Maternal Serum Screening (MSS) Program was introduced by the Ontario Ministry of Health as a province-wide pilot project in 1993. The objective of this study was to determine the influence of practice location on Ontario health care providers' use of and opinions regarding MSS, access to follow-up services and recommendations about the program.

METHODS

A questionnaire was mailed to a random sample of 2000 family physicians, all 565 obstetricians and all 62 registered midwives in Ontario between November 1994 and March 1995.

RESULTS

Among providers who were eligible (those providing antenatal care or attending births) the response rates were 91.4% (778/851), 76.0% (273/359) and 78.0% (46/59) respectively. Fewer respondents in the Northwest region (71.4%) and in rural areas (81.9%) stated that they routinely offer MSS to all pregnant women in their practices compared with respondents in other regions (84.4%-91.5%) and urban centres (90.1%). Fewer respondents in the northern regions (Northeast 49.2%, Northwest 25.0%) than in the Central East region (includes Toronto) (76.6%) felt that follow-up services were readily available. Respondents in the northern regions had less favourable opinions of MSS than those in the other regions in terms of its complexity, cost, the time involved in counselling and the high false-positive rate. More respondents in the Central East region (64.6%) and in urban centres (52.9%) recommended not changing the MSS program than did those in the Northwest (7.1%) and rural areas (39.8%). After provider characteristics were controlled for in a logistic regression analysis, practice location was not the most important factor. Instead, the model showed that respondents who cared for 50 or more pregnant women in the previous year were more likely to offer MSS routinely (OR 2.00, 95% CI 1.21-3.27) and that those who felt that patient characteristics affect the offering of MSS (OR 0.42, 95% CI 0.26-0.67) or that follow-up services were not readily available (OR 0.33, 95% CI 0.20-0.55) were less likely to offer it.

INTERPRETATION

Health care providers in northern and rural Ontario were less likely to offer MSS routinely than those in other regions and were more likely to recommend changing or eliminating the program. Providers' concerns about the social and cultural sensitivity of MSS and the availability of follow-up services affected use.

Purification of histone core octamers and 2.15 A X-ray analysis of crystals in KCl/phosphate

Intact histone octamers, produced by a new method quickly and in bulk, were crystallized in KCl/phosphate, and the X-ray data were analysed to 2.15 A, confirming a P65 space group. This environment preserves the high-resolution structure of the octamers and will be useful for studying them with other functionally important molecules. The octamers form into left-handed superhelices hexagonally spaced by 158.65 A, having a pitch of 102.57 A with six octamers per turn. A dipotassium tetraiodo mercurate derivative had good phasing power and should prove valuable in refining the structure after molecular-replacement analysis with lower resolution coordinates; the heavy atom was isomorphously placed at a unique site between the two H3-cysteine residues in the octamer.

Using the ALPHA form in practice to assess antenatal psychosocial health. Antenatal Psychosocial Health Assessment

BACKGROUND

The assessment of the psychosocial health of pregnant women and their families, although recommended, is not carried out by most practitioners. One reason is the lack of a practical and evidence-based tool. In response, a multidisciplinary group created the Antenatal Psychosocial Health Assessment (ALPHA) form. This article describes the development of this tool and experience with it in an initial field trial.

METHODS

A systematic literature review revealed 15 antenatal psychosocial risk factors associated with poor postpartum family outcomes of woman abuse, child abuse, postpartum depression, marital/couple dysfunction and increased physical illness. The ALPHA form, incorporating these risk factors, was developed and refined through several focus groups. It was then used by 5 obstetricians, 10 family physicians, 7 midwives and 4 antenatal clinic nurses in various urban, rural and culturally diverse locations across Ontario. After 3 months, these health care providers met in focus groups to discuss their experiences. A sample of pregnant women assessed using the ALPHA form were interviewed about their experience as well. Results were analysed according to qualitative methods.

RESULTS

The final version of the ALPHA form grouped the 15 risk factors into 4 categories--family factors, maternal factors, substance abuse and family violence--with suggested questions for each area of enquiry. The health care providers uniformly reported that the form helped them to uncover new and often surprising information, even when the women were well known to them. Incorporating the form into practice was usually accomplished after a period of familiarization. Most of the providers said the form was useful and would continue to use it if it became part of standard care. The pregnant women in the sample said they valued the enquiry and felt comfortable with the process, unless there were large cultural barriers.

INTERPRETATION

The ALPHA form appears to be an important tool in assessing psychosocial health in pregnancy and to be readily integrated into practice. More study is required to quantify the number of risks identified and resources used, to determine the form's reliability and validity and, ultimately, to assess the effect of its use on postpartum outcomes.

Diagnostic utility of fine needle aspiration (FNA) cytology in HIV-infected patients with lymphadenopathy

Sixty-five FNA cytology procedures were performed on lymph nodes in 52 HIV+ patients. Cervical lymph nodes were the commonest site of FNA cytology investigation (54%). The diagnoses were persistent generalized lymphadenopathy (38%), infection (17%), and malignancy (11%). Diagnosis could not be rendered in 25% of FNA cytology due to inadequate sampling. Of those with infection, mycobacterial disease was the commonest cause (91%), the diagnosis of which was enhanced by concurrent microbiological examination. Non-Hodgkin's lymphoma was the commonest malignancy. Sixteen lymph node FNA cytologies had subsequent tissue biopsy. There were two false-positive and four false-negative FNA cytologies. FNA cytology in HIV+ patients is most useful in the diagnosis of infection, obviating the need for tissue biopsy and allowing prompt initiation of treatment.

Churg-Strauss syndrome in a district hospital

Published series on Churg-Strauss syndrome (CSS) come from tertiary referral centres. We retrospectively studied 23 patients with CSS (18 male) seen over 14 years (1982-1995) in a District General Hospital serving a population of 500,000. Mean age of onset of vasculitis was 57, 10-19 years older than in previous series. The commonest clinical features were asthma (22) and eosinophilia > 1.5 x 10(9)/l (21). Systemic vasculitis involving two or more extrapulmonary organs occurred in 22 patients, with specific organ involvement of nervous system (18), joints (13), muscles (13), lungs (11), skin (11), kidneys (11), heart (10), and bowel (7). Various classification systems were applied including the Lanham criteria, which were met in 19 patients; the American College of Rheumatology criteria, met in 14; Churg and Strauss criteria, met in four; and the Chapel Hill Consensus definition, met only in two. ANCA was detected in 10/17 patients where measured. Treatment included corticosteroids (21), cyclophosphamide (8), azathioprine (9), immunoglobulin (2), and methotrexate (1). During follow-up six patients died, two due to myocardial vasculitis (mean age 52 years), three due to infection (mean age 80 years), and one cause unknown. Significant long-term disability was due to asthma in five and neuropathy in six.

Maternity care and maternal serum screening. Do male and female family physicians care for women differently?

OBJECTIVE

To examine whether male and female family physicians practise maternity care differently, particularly regarding the maternal serum screening (MSS) program.

DESIGN

Mailed survey fielded between October 1994 and March 1995.

SETTING

Ontario family practices.

PARTICIPANTS

Random sample of 2000 members of the College of Family Physicians of Canada who care for pregnant women. More than 90% of eligible physicians responded.

MAIN OUTCOME MEASURES

Attitudes toward, knowledge about, and behaviour toward MSS.

RESULTS

Women physicians were more likely than men to practise part time, in groups, and in larger communities. Men physicians were more likely to perform deliveries; women were more likely to do shared care. Despite a shorter work week, on average, female physicians cared for more pregnant women than male physicians did. Among those providing intrapartum care, women performed more deliveries, on average, than men. Women physicians were more likely than men to offer MSS to all pregnant patients. Although average time spent discussing MSS before the test was similar, women physicians had better knowledge of when best to do the test and its true-positive rate. All differences reported were statistically significant (P < or = 0.001).

CONCLUSIONS

Among family physicians caring for pregnant women, women physicians cared for more pregnant women than men did. Both spent similar time discussing MSS with their patients before offering screening, but more women physicians offered MSS to all their patients and were more knowledgeable about MSS than men physicians.

Ontario Maternal Serum Screening Program: practices, knowledge and opinions of health care providers

OBJECTIVE

To determine the practices, knowledge and opinions of health care providers regarding a prenatal genetic screening program in Ontario.

DESIGN

Cross-sectional self-reported survey.

SETTING

Ontario.

PARTICIPANTS

Random sample of 2000 family physicians, all 565 obstetricians and all 62 registered midwives in the province. Among subjects who were eligible (those providing antenatal care or attending births) the response rates were 91% (778/851), 76% (273/359) and 78% (46/59) respectively.

MAIN OUTCOME MEASURES

Which patients were offered maternal serum screening (MSS), how results were being communicated, knowledge of the test's sensitivity, likes and dislikes about MSS and recommendations regarding the program.

RESULTS

Most (97%) of respondents stated that they were offering MSS to the pregnant women in their practices; 88% were offering it routinely to all pregnant women (87% of the family physicians, 90% of the obstetricians and 100% of the midwives). Most (92%) of the respondents stated that they communicate positive results to their patients personally as soon as they are received; 23% did so for negative results. The respondents correctly identified the initial positive rate but underestimated the false-positive rate. About one-third did not respond to these knowledge questions. Of those who gave feedback on the screening program, 50% recommended that it not be changed, 29% suggested that it be changed, and 22% recommended that it be scrapped.

CONCLUSIONS

Participation in the Ontario Maternal Serum Screening Program by health care providers has been good, although knowledge about MSS is far from ideal. Many providers have reservations about the program. In light of concerns raised about the high false-positive rate and the anxiety such results generate in pregnant women, there is a need for more education of providers and patients and a better understanding of women's experiences with genetic screening.

Antenatal psychosocial risk factors associated with adverse postpartum family outcomes

OBJECTIVE

To determine the strength of the association between antenatal psychosocial risk factors and adverse postpartum outcomes in the family, such as assault of women by their partner, child abuse, postpartum depression, marital dysfunction and physical illness.

DATA SOURCES

MEDLINE, Cinahl, Famli, Psych Abstracts and the Oxford Database of Perinatal Trials were searched from relevant articles published from Jan. 1, 1980, to Dec. 31, 1993, with the use of MeSH terms "depression, involutional," "child abuse," "child neglect," "domestic violence," "family," "marital adjustment," "family health," "newborn health," "child health," "physical illness," "social support," "psychosocial risk," "prediction," "risk factors," "obstetrics" and "prenatal care." Further articles were identified from bibliographies.

STUDY SELECTION

Of the 370 articles identified through the search, 118 were included for review. Studies were included if they examined the association between psychosocial risk factors and the outcomes of interest. Articles were excluded if they were reviews of poor quality or they had one or more of the following features: insufficient description of the sample, a high attrition rate, a lack of standardized outcome measures, outcomes other than the ones of interest or results that had already been reported in a previous study.

DATA EXTRACTION

The strength of evidence of each study was evaluated. On the basis of the evidence, each risk factor was assigned a rating of the strength of its association with each of the postpartum outcomes. The ratings were class A (good evidence of association), class B (fair evidence) and class C (no clear evidence). Of the 129 antenatal psychosocial risk factors studied, 15 were found to have a class A association with at least one of the postpartum outcomes.

DATA SYNTHESIS

Child abuse and abuse of the mother by her partner were most strongly correlated (class A evidence) with a history of lack of social support, recent life stressors, psychiatric disturbance in the mother and an unwanted pregnancy. Child abuse was also strongly associated with a history of childhood violence in the mother or her partner, previous child abuse by the mother's partner, a poor relationship between the mother and her parents, low self-esteem in the mother and lack of attendance at prenatal classes. Postpartum abuse of the mother was also associated with a history of abuse of the mother, prenatal care not started until the third trimester and alcohol or drug abuse by the mother or her partner (class A evidence). Child abuse had a fair (class B) association with poor marital adjustment or satisfaction, current or past abuse of the mother and alcohol or drug abuse by the mother or her partner. There was class B evidence supporting an association between abuse of the mother and poor marital adjustment, traditional sex-role expectations, a history of childhood violence in the mother or her partner and low self-esteem in the mother. Postpartum depression was most strongly associated with poor marital adjustment, recent life stressors, antepartum depression (class A evidence), but was also associated with lack of social support, abuse of the mother and a history of psychiatric disorder in the mother (class B evidence). Marital dysfunction was associated with poor marital adjustment before the birth and traditional sex-role expectations (class A evidence), and physical illness was correlated with recent life stressors (class B evidence).

CONCLUSIONS

Psychosocial risk factors during the antenatal period may herald postpartum morbidity. Research is required to determine whether detection of these risk factors may lead to interventions that improve postpartum family outcomes.

Female family physicians in obstetrics: achieving personal balance

OBJECTIVE

To describe the experiences of female family physicians who practise obstetrics in balancing professional obligations with personal and family needs, given the unique challenges that such practice poses for these physicians.

DESIGN

Qualitative study.

SETTING

Ontario.

PARTICIPANTS

A purposefully selected sample of nine female family physicians who met the criteria of being married, having children and currently practising obstetrics.

OUTCOME MEASURES

Experiences of female family physicians and their strategies in their personal, family and professional lives that enable them to continue practising obstetrics.

RESULTS

All participants continued to practise obstetrics because of the pleasure they derived from it, despite the challenges of balancing the unpredictable demands of obstetrics with their personal and family needs. To continue in obstetrics, they needed to make changes in their lives, either through a gradual, evolutionary process or in response to a critical event. Alterations to work and family arrangements permitted them to meet the challenges and led to increased satisfaction. Changes included making supportive call-group arrangements, limiting work hours and the number of births attended and securing help with household duties.

CONCLUSIONS

An in-depth examination, through the use of qualitative methods, showed the reasons why some female family physicians continue to practise obstetrics despite the stressful aspects of doing so. This knowledge may be useful for women who are residents or experienced clinicians and who are considering including obstetrics in their practice.

Consultation in family practice obstetrics

PURPOSE

To examine the types of non-low-risk obstetric patients managed by family physicians in urban teaching hospitals, and to determine indications for consultation for women at low risk when labour began.

METHOD

Retrospective chart review for all patients delivered by family physicians in three downtown Toronto teaching hospitals during 1 year.

RESULTS

Of 1710 cases, 595 (34.8%) were classified as non-low risk, with the main indications being postdates (> 42 weeks) (19.9%); pregnancy-induced hypertension (19.3%); and premature labour (< 37 weeks) (14.8%). Of the 1115 low-risk patients, 363 (32.6%) had an intrapartum consultation, usually for failure to progress (50.1%) or fetal distress (12.7%). More than 80% of intrapartum consultations were associated with induction and augmentation of labour.

CONCLUSION

Family physicians can continue to care for many non-low-risk women, usually with the help of obstetricians. Consultations were obtained for many women at low risk. We need to reevaluate whether some mandatory consultations are necessary in family practice obstetrics.

Psychosocial risk factors during pregnancy. What do family physicians ask about?

OBJECTIVE

To determine whether physician characteristics affect attitudes or practices regarding assessment of psychosocial risk factors during pregnancy, and to evaluate whether an antenatal psychosocial risk factor assessment form would help family physicians.

DESIGN AND SETTING

A questionnaire asking physicians to rate the importance of information on a scale of one to five was mailed to all active members of the University of Toronto Department of Family and Community Medicine's Survey Network of Attitudes and Practice (SNAP).

PARTICIPANTS

A volunteer sample of physicians doing prenatal and intrapartum obstetrics who are active members of SNAP. The network is made up of full-time faculty in the University of Toronto's family practice units and teaching practice physicians (rural, suburban, and urban) who are interested in participating in research projects.

MAIN OUTCOME MEASURES

Response rate was 78%. Responses of the 45 SNAP members who did not practise obstetrics were excluded; 125 of 218 questionnaires mailed were analyzed.

RESULTS

Women family physicians rated the form potentially helpful more frequently than their male colleagues. Urban and suburban physicians' concerns differed from those of rural physicians. Alcohol and drug abuse, abuse in the relationship, and acceptance of the pregnancy were rated highly important by physicians. Of the physicians surveyed, 77% thought that an antenatal psychosocial risk assessment form would be of some benefit or very helpful. Only 15% indicated it would be useless or not helpful.

CONCLUSION

The importance respondents accorded to risk factors showed little correspondence to the frequency of inquiry about them. The survey confirmed our plan to design an antenatal psychosocial risk factor assessment form.

Are physicians changing the way they practise obstetrics?

OBJECTIVE

To examine trends in obstetric interventions in women at low risk over approximately 3 years. It was postulated that there would be a general reduction in most intervention rates.

DESIGN

Retrospective review of hospital records.

SETTING

Three downtown hospitals of the University of Toronto, in which academic and nonacademic family physicians and obstetricians practised.

PATIENTS

A total of 2365 women in phase 1 (April 1985 to March 1986) and 1277 in phase 2 (May to September 1988) met the inclusion criteria for grade A (pregnancy at no predictable risk) of the Ontario Antenatal Record at the time of admission to hospital.

OUTCOME MEASURES

Rates of artificial rupture of the membranes, induction, augmentation, epidural anesthesia, continuous electronic fetal monitoring (EFM), instrumental delivery, episiotomy and cesarean section.

RESULTS

The family physicians and the obstetricians had significant decreases (p < 0.01) over time in the rates of episiotomy, especially mediolateral, and low forceps delivery. The rate of epidural anesthesia decreased significantly in the obstetrician group. The rates of artificial rupture of the membranes, induction and continuous EFM increased in the two physician groups; the increased rate of EFM was significant in the obstetrician group (p < 0.01). There was no significant change in the rates of augmentation, midforceps delivery, vacuum extraction or cesarean section. All of the trends were found to hold when the intervention rates were analysed according to the women's parity.

CONCLUSIONS

Some of the findings reflect recommendations and trends reported in the literature, whereas others are not supported by clear medical evidence. The unpredictable nature of the trends suggests that further study is warranted of the reasons for obstetric trends and for the changes in physicians' practice patterns.

Echocolonoscopy--an indispensable procedure before and after transanal endoscopic microsurgery

As a refinement of the widely practised intraluminal sonography, echocolonoscopy represents a breakthrough in preoperative staging and post-operative follow-up of rectal tumor patients. Enabling colonoscopy and intraluminal sonography to be performed in one session, optical control with the Olympus echocolonoscope also prevents inaccurate endosonographic diagnosis caused by tangential cuts or mistaken interpretation of faeces adhering to the mucosa. In the era of transanal endoscopic microsurgery, echocolonoscopy acquires enhanced importance as a pre- and post-operative tool.

Episiotomy: Differences in practice between family physicians and obstetricians

A review of 2188 records compared the numbers and types of episiotomies and tears in low-risk women delivered by family physicians and obstetricians. Family physicians performed significantly fewer episiotomies and were more likely to rely on the mediolateral procedure; obstetricians varied episiotomy type more often. The rates of third-degree tears and intact perineum were very similar.

Choosing to Practise Obstetrics: What factors influence family practice residents?

To document their plans for practising obstetrics and factors influencing these decisions, a questionnaire was sent to all 79 residents graduating from the University of Toronto's Department of Family and Community Medicine. Fifty-one percent of the 53 residents who responded (67%) planned to practise obstetrics on graduation; 21% planned antenatal care only; 11% planned no obstetrics; and 17% were undecided. The family practice program appeared to influence the residents positively.

The influence of the high-risk care environment on the practice of low-risk obstetrics

This retrospective chart review compared the intervention rates in 2,365 low-risk obstetric patients at three urban teaching hospitals, two of which were high-risk, perinatal referral centers. The third cared for mostly low-risk patients. The hypothesis was that rates of intervention in low-risk pregnancies would be higher in the high-risk care environment. Family physicians at the perinatal referral centers performed significantly more artificial rupture of membranes, epidural blocks, augmentations of labor, and episiotomies on their low-risk patients than did those at the low-risk hospital. This trend was also found for obstetricians but did not reach statistical significance. Thus, the conclusion was drawn that caring for low-risk patients in a high-risk care environment is associated with a higher intervention rate by family physicians. Factors that may contribute to this finding are discussed.

Maternal mortality: preventing the tragedy in developing countries

Maternal mortality in childbirth has been, until recently, a neglected tragedy in most developing countries. Rates of maternal deaths range from 300 to 700/100 000 live births, from 50 to 100 times greater in developing than in developed countries. The major direct obstetric causes include illegal abortions, hemorrhage, sepsis, obstructed labour, ruptured uterus, and pregnancy-induced hypertension. During the past decade, increased recognition of this problem has led to the "Safe Motherhood Initiative" by the World Health Organization in 1987, which has been integrated into the goal of "Health for All by the Year 2000." The training of traditional birth attendants (who attend from 40% to 60% of births in developing countries) is seen as one of the most important ways to improve obstetric care in remote rural villages.

Differences in intrapartum obstetric care provided to women at low risk by family physicians and obstetricians

To determine differences in practice style and to examine maternal and neonatal outcomes, we reviewed the hospital charts of 1115 women admitted by family physicians and 1250 women admitted by obstetricians who gave birth at one of three teaching hospitals in Toronto between April 1985 and March 1986. All the women in the two groups were categorized retrospectively as being at low risk at the onset of labour on the basis of their prenatal records and their admission histories and physical examination results. There were higher proportions of younger women and women of lower socioeconomic status in the family physician group than in the obstetrician group (p less than 0.001). The rates of interventions, including artificial rupture of the membranes, induction, augmentation, low forceps plus vacuum extraction, episiotomy and epidural anesthesia, were all higher in the obstetrician group. The mean birth weight and the cesarean section rate were the same in the two groups. Differences in labour and delivery outcomes between the two groups, including a higher rate of spontaneous vaginal delivery for the family physicians, reflected a more "expectant" practice style by family doctors. However, there were no significant differences in the rates of maternal or neonatal complications. A practice style characterized by a higher rate of interventions was not associated with improved maternal or newborn outcome in this low-risk setting.

Midwifery in a family practice

This study examined the effect on the type of maternity care given low-risk mothers in a family practice where approximately one-half of the patients were coached in labour by midwives. It was found that the same caregiver tended to make fewer obstetrical interventions with the midwife-coached patients. While the study was not methodologically rigorous, it nevertheless illustrated trends that the authors believed to be valid when midwives were involved. Future studies might document the trends more clearly and suggest areas for co-operation between family doctors and midwives.

Alternative birth positions

The dorsal supine position for birth appears to be an aberration practised only in North America during the last 150 years and contrasting to historical precedent and current practices in most other cultures. Alternative birth positions featuring reclining, sitting, squatting or side-lying have recently been shown to have definite physiological and psychological advantages over the conventional posture. The author of this article examines the evidence supporting these advantages and illustrates how these birthing positions may be incorporated into hospital birthing procedures.

Cephaloridine resistance in gram-negative bacteria isolated in Scotland

The incidence of cephaloridine resistance (minimum inhibitory concentration, MIC greater than 8 mg L-1) in isolates from urinary tract infections was 45.1% in Glasgow, 22.6% in Dundee and 25.9% in Edinburgh. The incidence of ampicillin resistance (MIC greater than 8 mg L-1) was even higher:- being 45.2% in Dundee and 48.5% in Edinburgh. In Glasgow, the incidence was 71.9% which is the highest proportion of ampicillin resistance reported in the United Kingdom. The cephaloridine resistant strains were examined for beta-lactamase production. Amongst these strains 50.8% produced only a chromosomal beta-lactamase, whereas 47.9% produced beta-lactamases which were potentially plasmid-mediated on the basis of biochemical tests. Only 1% of the resistant strains produced no detectable beta-lactamase.

The differential expression of genes for the PSE-4 beta-lactamase in Pseudomonas aeruginosa and the Enterobacteriaceae

The PSE-4 beta-lactamase has been identified, for the first time, in two non-pseudomonal strains. The gene in Klebsiella pneumoniae 241 (dal1) was located on a plasmid (pUK700) and was freely transferable to other enterobacterial strains and Pseudomonas aeruginosa. On the other hand, the gene in Enterobacter cloacae A113 (dal2) could only be transferred in the presence of a mobilizing plasmid. When both these genes were transferred within the Enterobacteriaceae, the beta-lactamase produced was slightly different from the prototype 'Dalgleish' PSE-4 enzyme. However, when dal1 and dal2 were transferred to P. aeruginosa the enzyme expressed was identical to this prototype enzyme. In addition, both these genes expressed higher levels of PSE-4 beta-lactamase production in P. aeruginosa than found in the Enterobacteriaceae. Thus it appears that the biochemical properties of the PSE-4 gene products from dal1 and dal2 are host-modified.

Midwifery and family practice

With the release of the report of the Task Force on the Implementation of Midwifery in Ontario, in October 1987, it is clear that midwives will be legally practising in this province in the near future and probably, with time, in the rest of Canada also. Does this prospect pose a threat to family practitioners who wish to continue doing obstetrics? The author of this paper discusses the recommendations of the Task Force and argues that the introduction of midwifery should not be seen as representing competition for family physicians but as a positive step which may provide collaboration for low-risk maternity care. A number of models of co-operation are presented.

Ampicillin resistance in Haemophilus influenzae: identification of resistance mechanisms

The incidence and mechanisms of ampicillin resistance (MIC greater than 1 mg/l) were investigated in 105 clinical isolates of Haemophilus influenzae collected in Edinburgh during 1983/4. Fifteen (14.3%) ampicillin-resistant strains were identified and these were non-serotypable and comprised six biotypes. Isoelectric focusing and beta-lactamase-inhibition studies demonstrated that production of the TEM-1 beta-lactamase was the principal mechanism of resistance in nine (60%) strains. Radiolabelling revealed that one beta-lactamase-positive strain also had an unusual penicillin-binding protein (PBP) profit. No beta-lactamase activity was detected in the other six (40%) ampicillin-resistant strains. Two beta-lactamase-negative ampicillin-resistant strains had atypical PBP profiles. SDS-PAGE analysis showed that four beta-lactamase-negative ampicillin-resistant strains, including one with altered PBPs, exhibited outer membrane protein profiles which differed from those of sensitive strains of the same biotype. The ampicillin-resistance mechanism of the remaining strain could not be determined. Thus, several resistance mechanisms, either acting individually or in combination, are implicated in ampicillin resistance in H. influenzae.

VBAC: Is It Safe for Your Patients?

Vaginal birth after caesarean section (VBAC) is being increasingly considered as an alternative to elective repeat section, in order to help reduce overall caesarean rates and achieve improved perinatal outcomes. This review examines the evidence for the safety of VBAC compared to the traditional practice of "Once a caesarean, always a caesarean." It appears that the incidence of uterine rupture is much lower than previously thought (less than 1%), and that the rates of overall fetal and maternal mortality improve with the use of VBAC. A number of associated treatments such as epidural anesthesia and oxytocin use are also examined.

Plasmid penicillin resistance in Vibrio cholerae: identification of new beta-lactamase SAR-1

Two strains of Vibrio cholerae biotype El Tor, isolated in Tanzania, possessed a single IncC resistance plasmid of 113 kilobases. Both plasmids encoded the production of a novel beta-lactamase, SAR-1, which was 33,700 daltons in size and was able to hydrolyze carbenicillin as well as penicillin G. The SAR-1 beta-lactamase was quite distinct from all other plasmid beta-lactamases by virtue of its unusually low isoelectric point and a combination of its size, substrate profile, and inhibition properties. This enzyme is only the second beta-lactamase identified in V. cholerae species and the first to be reported in V. cholerae strains isolated in Southern Africa.

Night-time sleep EEG changes following body heating in a warm bath

Six healthy female volunteers (22-24 years), physically untrained (unfit), sat in baths of warm or cool water for 90 min, between 14.30 h and 17.30 h, on separate occasions. In the former condition (HOT), rectal temperature (Tr) rose by an average of 1.8 degrees C, and in the latter (COOL), a thermoneutral condition, there was a nil Tr change. All-night sleep EEGs were monitored after both occasions and on baseline nights. Following COOL, there was no significant change in any sleep parameter. After HOT there were significant increases in: sleepiness at bed-time, slow wave sleep, and stage 4 sleep. REM sleep was reduced, particularly in the first REM sleep period.

Wegener's granulomatosis and the respiratory system

Wegener's granulomatosis is a disease characterized by necrotizing vasculitis of the upper and lower respiratory tracts, necrotizing glomerulonephritis, and varying degrees of disseminated small vessel vasculitis. Patients can present to an otolaryngologist head and neck surgeon with ear, nose, throat, lung, orbit, salivary gland, or cutaneous lesions. The disease is variable in its presentation and progression. Tissue biopsies may be non-diagnostic even in the presence of active disease. Although the disease was rapidly fatal as recently at 1970, it can now be effectively treated. This paper reviews the diagnosis and management of Wegener's granulomatosis at a major university hospital between 1965 and 1979. during this period there was a significant evolution of treatment methods.