Chest pain in the dental surgery: A brief review and practical points in diagnosis and management

If a dental patient develops chest pain it must always be managed promptly and properly, i.e., the practitioner immediately stops the procedure and, being aware of the patients's medical history, questions the patient regarding the nature of the pain to help determine the likely diagnosis. It will most likely be a manifestation of coronary artery disease (synonymous with ischaemic heart disease), i.e., angina pectoris or acute myocardial infarction, most usually the former. Angina will usually resolve with proper intervention whereas up to about one-half of myocardial infarction cases will develop cardiac arrest, mostly in the first few hours, and this will be fatal in up to two-thirds of cases. As health care professions, dental practitioners have an inherent duty of care to be able to initiate appropriate care if such a medical emergency occurs.

Positive genetic correlation between female preference and offspring fitness

In many species, females display preferences for extreme male signal traits, but it has not been determined if such preferences evolve as a consequence of females gaining genetic benefits from exercising choice. If females prefer extreme male traits because they indicate male genetic quality that will enhance the fitness of offspring, a genetic correlation will evolve between female preference genes and genes that confer offspring fitness. We show that females of Drosophila serrata prefer extreme male cuticular hydrocarbon (CHC) blends, and that this preference affects offspring fitness. Female preference is positively genetically correlated with offspring fitness, indicating that females have gained genetic benefits from their choice of males. Despite male CHCs experiencing strong sexual selection, the genes underlying attractive CHCs also conferred lower offspring fitness, suggesting a balance between sexual selection and natural selection may have been reached in this population.

Impact of malocclusion and orthognathic reconstruction surgery on resonance and articulatory function: an examination of variability in five cases

Articulatory patterns and nasal resonance were assessed before and 6 months after orthognathic reconstruction surgery in five patients with dentofacial deformities. Perceptual and physiological assessments showed disorders of nasality and articulatory function preoperatively, two patients being hyponasal, and one hypernasal. Four patients had mild articulatory deficits, and four had reduced maximal lip or tongue pressures. Operation resulted in different patterns of change. Nasality deteriorated in three patients and articulatory precision and intelligibility improved in only one patient and showed no change in the other four. Operation improved interlabial pressures in three patients, while its impact on tongue pressures varied, being improved in one case, deteriorating in one, and remaining unchanged in the other three. The variability in the results highlights the need for routine assessment of speech and resonance before and after orthognathic reconstruction. (C) 2002 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Science Ltd. All rights reserved.

Do female rainbowfish (Melanotaenia spp.) prefer to shoal with familiar individuals under predation pressure?

Shoaling with familiar individuals may have many benefits including enhanced escape responses or increased foraging efficiency. This study describes the results of two complimentary experiments. The first utilised a simple binary choice experiment to determine if rainbowfish (Melanotaenia spp.) preferred to shoal with familiar individuals or with strangers. The second experiment used a free range situation where familiar and unfamiliar individuals were free to intermingle and were then exposed to a predator threat. Like many other small species of fish, rainbowfish were capable of identifying and distinguishing between individuals and choose to preferentially associate with familiar individuals as opposed to strangers. Contrary to expectations. however. rainbowrish did not significantly increase their preference for familiar individuals in the presence of a stationary predator model. Griffiths [J Fish Biol (1997) 51:489-4951 conducted similar studies under semi-natural conditions examining, the shoaling preferences of European minnows and showed similar results. Both the current study and that of Griffiths were conducted using predator wary populations of fish. It is suggested that, in predator sympatric populations, the benefits of shoaling with familiar individuals are such that it always pays to stay close to familiar individuals even when the probability If predator attack is remote.

Usefulness of clinical risk markers and ischemic threshold to stratify risk in patients undergoing major noncardiac surgery

The risk of cardiac events in patients undergoing major noncardiac surgery is dependent on their clinical characteristics and the results of stress testing. The purpose of this study was to develop a composite approach to defining levels of risk and to examine whether different approaches to prophylaxis influenced this prediction of outcome. One hundred forty-five consecutive patients (aged 68 +/- 9 years, 79 men) with >1 clinical risk variable were studied with standard dobutamine-atropine stress echo before major noncardiac surgery. Risk levels were stratified according to the presence of ischemia (new or worsening wall motion abnormality), ischemic threshold (heart rate at development of ischemia), and number of clinical risk variables. Patients were followed for perioperative events (during hospital admission) and death or infarction over the subsequent 16 10 months. Ten perioperative events occurred in 105 patients who proceeded to surgery (10%, 95% confidence interval [CI] 5% to 17%), 40 being cancelled because of cardiac or other risk. No ischemia was identified in 56 patients, 1 of whom (1.8%) had a perioperative infarction. Of the 49 patients with ischemia, 22 (45%) had 1 or 2 clinical risk factors; 2 (9%, 95% CI 1% to 29%) had events. Another 15 patients had a high ischemic threshold and 3 or 4 risk factors; 3 (20%, 95% Cl 4% to 48%) had events. Twelve patients had a low ischemic threshold and 3 or 4 risk factors; 4 (33%, 95% CI 10% to 65%) had events. Preoperative myocardial revascularization was performed in only 3 patients, none of whom had events. Perioperative and long-term events occurred despite the use of beta blockers; 7 of 41 eta blocker-treated patients had a perioperative event (17%, 95% CI 7% to 32%); these treated patients were at higher anticipated risk than untreated patients (20 +/- 24% vs 10 +/- 19%, p = 0.02). The total event rate over late follow-up was 13%, and was predicted by dobutamine-atropine stress echo results and heart rate response. (C) 2002 by Excerpta Medica, Inc.

Physiological responses to the menstrual cycle - Implications for the development of heat illness in female athletes

Fluctuations in estrogen and progesterone during the menstrual cycle can cause changes in body systems other than the reproductive system. For example, progesterone is involved in the regulation of fluid balance in the renal tubules and innervation of the diaphragm via the phrenic nerve. However, few significant changes in the responses of the cardiovascular and respiratory systems, blood lactate, bodyweight, performance and ratings of perceived exertion are evident across the cycle. Nevertheless, substantial evidence exists to suggest that increased progesterone levels during the luteal phase cause increases in both core and skin temperatures and alter the temperature at which sweating begins during exposure to both ambient and hot environments. As heat illness is characterised by a significant increase in body temperature, it is feasible that an additional increase in core temperature during the luteal phase could place females at an increased risk of developing heat illness during this time. In addition, it is often argued that physiological gender differences such as oxygen consumption, percentage body fat and surface area-to-mass ratio place females at a higher risk of heat illness than males. This review examines various physiological responses to heat exposure during the menstrual cycle at rest and during exercise, and considers whether such changes increase the risk of heat illness in female athletes during a particular phase of the menstrual cycle.

Shoulder movement after breast cancer surgery: results of a randomised controlled study of postoperative physiotherapy

Breast screening programmes have facilitated more conservative approaches to the surgical and radiotherapy management of women diagnosed with breast cancer. This study investigated changes in shoulder movement after surgery for primary, operable breast cancer to determine the effect of elective physiotherapy intervention. Sixty-five women were randomly assigned to either the treatment (TG) or control group (CG) and assessments were completed preoperatively, at day 5 and at 1 month, 3, 6, 12 and 24 months postoperatively. The CG only received an exercise instruction booklet in comparison to the TG who received the Physiotherapy Management Care Plan (PMCP). Analyses of variance revealed that abduction returned to preoperative levels more quickly in the TG than in the CG. The TG women had 14degrees more abduction at 3 months and 7degrees at 24 months. Functional recovery at 1 month was greater in those randomised to the TG, with a dominant operated arm (OA) or receiving breast-conserving surgery. However, it was not possible to predict recovery over the 2 years postoperatively on the basis of an individual woman's recovery at 1 month postoperatively. The eventual recovery of abduction or flexion range of movement was not related to the dominance of the OA nor to the surgical procedure performed. The PMCP provided in the early postoperative period is effective in facilitating and maintaining the recovery of shoulder movement over the first 2 years after breast cancer surgery.

Physiotherapy after breast cancer surgery: results of a randomised controlled study to minimise lymphoedema

The development of secondary arm lymphoedema after the removal of axillary lymph nodes remains a potential problem for women with breast cancer. This study investigated the incidence of arm lymphoedema following axillary dissection to determine the effect of prospective monitoring and early physiotherapy intervention. Sixty-five women were randomly assigned to either the treatment (TG) or control group (CG) and assessments were made preoperatively, at day 5 and at 1, 3, 6, 12 and 24 months postoperatively. Three measurements were used for the detection of arm lymphoedema: arm circumferences (CIRC), arm volume (VOL) and multi-frequency bioimpedance (MFBIA). Clinically significant lymphoedema was confirmed by an increase of at least 200 ml from the preoperative difference between the two arms. Using this definition, the incidence of lymphoedema at 24 mo. was 21%, with a rate of 11% in the TG compared to 30% in the CG. The CIRC or MFBIA methods failed to detect lymphoedema in up to 50% of women who demonstrated an increase of at least 200 ml in the VOL of the operated arm compared to the unoperated arm. The physiotherapy intervention programme for the TG women included principles for lymphoedema risk minimisation and early management of this condition when it was identified. These strategies appear to reduce the development of secondary lymphoedema and alter its progression in comparison to the CG women. Monitoring of these women is continuing and will determine if these benefits are maintained over a longer period for women with early lymphoedema after breast cancer surgery.

Patterns of lipid storage and mobilisation in the female green sea turtle (Chelonia mydas)

Reproductive data from southern Queensland indicate that vitellogenesis in female Chelonia mydas takes approximately 8 months and is followed by a migration to a breeding area. At Heron Island, females lay multiple clutches over approximately 3 months. To investigate how females mobilise and store lipid during the breeding season we collected plasma, yolk, and fat tissue samples from females at a variety of stages during the nesting season. In breeding females, concentrations of plasma triglyceride increased seasonally. They reached peak concentrations during vitellogenesis and courtship, remained high throughout the nesting season, and then declined to a nadir after the last clutch. Plasma protein concentration increased throughout the breeding season, peaking following the last clutch for the season. Yolk lipids were highest during courtship and were similar throughout the nesting season, suggesting that uptake of lipid by ovarian follicles is completed prior to the beginning of the nesting season. Plasma triglyceride decreases in females with prolonged periods of unsuccessful nesting, and total lipid levels in adipose tissue and follicle yolks were significantly lower in atretic females. It appears that: (1) endogenous energy reserves can be reduced by stochastic environmental events (such as those reducing nesting success), and (2) a metabolic shift signalling the end of the nesting season is characterised by a drop in plasma triglycerides and slight increase in total plasma protein.

Interactions among endocrinology, seasonal reproductive cycles and the nesting biology of the female green sea turtle

We collected data on plasma levels of testosterone+5a-dihydrotestosterone (T+DHT) and corticosterone (CORT) from adult female green sea turtles (Chelonia mydas) from southern Queensland during distinct stages of their reproductive cycle. Those females capable of breeding in a given year had elevated plasma steroid levels (T+DHT 0.91 +/- 0.08; CORT 1.05 +/- 0.29 ng/ml), associated with follicular development, until courtship began in October. At the beginning of the nesting season in November plasma levels of 2 CORT were related to when the female first nested (r(2) = 0.06; F = 10.45; P = 0.01). However, they were not correlated with the number of clutches a female laid in that season (F = 3.65; P = 0.08). We repeatedly sampled 23 turtles over the nesting season and profiled changes in steroids immediately following oviposition of each clutch. Levels of T+DHT (range 0.41-0.58 ng/ml) and CORT (range 2.13-2.81 ng/ml) were similar through the early stages of the nesting season and inter-nesting period, and declined to near basal levels (T+DHT 0.37 +/- 0.03 and CORT 1.85 +/- ng/ml) following the last clutch for the season. Steroid hormone levels were also low (T+DHT 0.38 +/- 0.16; CORT 0.46 +/- 0.21 ng/ml) in four independent post-breeding (atretic) females; samples for these females were taken at a time when body condition was presumably at the lowest for the season. Subtle changes in the nesting environment, such as variation in nesting habitat or the time of night that nesting occurred, were associated with a small and slow CORT increase. We suggest CORT is increased in nesting females to assist in lipid transfer to prepare the ovarian follicles and/or the reproductive organs for ovulation.

Age does not influence the bone response to treadmill exercise in female rats

Purpose: Because it is believed that bone may respond to exercise differently at different ages, we compared bone responses in immature and mature rats after 12 wk of treadmill running. Methods: Twenty-two immature (5-wk-old) and 21 mature (17-wk-old) female Sprague Dawley rats were randomized into a running (trained, N = 10 immature, 9 mature) or a control group (controls, N 12 immature, 12 mature) before sacrifice 12 wk later. Rats ran on a treadmill five times per week for 60-70 min at speeds up to 26 m.min(-1). Both at baseline and after intervention, we measured total body, lumbar spine, and proximal femoral bone mineral, as well as total body soft tissue composition using dual-energy x-ray absorptiometry (DXA) in vivo. After sacrificing the animals, we measured dynamic and static histomorphometry and three-point bending strength of the tibia. Results: Running training was associated with greater differences in tibial subperiosteal area, cortical cross-sectional area, peak load, stiffness, and moment of inertia in immature and mature rats (P < 0.05). The trained rats had greater periosteal bone formation rates (P < 0.01) than controls, but there was no difference in tibial trabecular bone histomorphometry. Similar running-related gains were seen in DXA lumbar spine area (P = 0.04) and bone mineral content (BMC; P = 0.03) at both ages. For total body bone area and BMC, the immature trained group increased significantly compared with controls (P < 0.05), whereas the mature trained group gained less than did controls (P < 0.01). Conclusion: In this in vivo model, where a similar physical training program was performed by immature and mature female rats, we demonstrated that both age groups were sensitive to loading and that bone strength gains appeared to result more from changes in bone geometry than from improved material properties.

Early reoperation for acute dysphagia following laparoscopic fundoplication

Background: A small number of patients develop acute severe dysphagia for which reoperation is necessary within 10 days of laparoscopic fundoplication. The aim of this study was to identify clinical variables that might predict the likelihood of this condition occurring, such that it could be avoided in the future. Methods: This was a prospective cohort study from three tertiary referral centres, using reoperation for acute dysphagia as the main outcome variable. Gastrointestinal symptom rating scale, and psychological well-being index questionnaires were undertaken before laparoscopic fundoplication, and dysphagia scores were determined before operation and 1 year later. Standard preoperative assessment included gastroscopy, oesophageal manometry and pH studies. Results: Twelve (1.9 per cent) of the 617 patients suffered acute dysphagia, which was predicted by older age and female sex, and resulted in a longer duration of hospital stay. This condition was not predicted by any other demographic, clinical, investigative or operative variables. Conclusions: The study did not identify useful criteria by which severe acute dysphagia could be anticipated and thereby avoided following laparoscopic fundoplication.

Couple communication and female problem drinking: A behavioral observation study

Couples with alcohol and relationship problems often report poor communication, yet little is known about the communication of maritally distressed couples in which the woman abuses alcohol (MDWA couples). Compared with maritally distressed couples without alcohol problems (MDNA) and couples with neither problem (NDNA), MDWA couples showed a distinctive pattern of negative communication. Similar to MDNA men, MDWA men spoke negatively to their partners but listened positively to their partners much like NDNA men. MDWA women listened negatively, much as MDNA women did, but spoke positively, like NDNA women did. The interactions of MDWA couples can be characterized as a male-demand-female-withdraw pattern, which is a gender reversal of the female-demand-male-withdraw pattern often observed in MDNA couples.