Linear basal cell carcinoma: A distinct clinical entity

The purpose of the study is to describe linear basal cell carcinoma (BCC) as a distinct clinical entity, and highlight its existence to the plastic surgery literature. A Medline and PubMed literature search was conducted, and 33 reported cases of linear BCC were analysed. Of these 33 cases, the most common site for linear BCC was the periocular region, accounting for 49% (n= 16). The most common histologic subtype, was nodular BCC, accounting for 50% (n= 17). Of the 33 reported cases the postoperative defect size was mentioned in five cases only. None of these would have been completely excised if a 2 mm margin was applied, and only one out of five if a 4 mm margin was applied. Linear BCC is a distinct clinical entity. Presence of the tumour along relaxing skin tension lines, increase in subclinical extension, and aggressive tumour behavior are reported observations. Because of these observations it is suggested that margin-controlled excision should be considered for linear BCC.

Oceanographic Basis of the Global Surface Distribution of Prochlorococcus Ecotypes

By using data collected during a continuous circumnavigation of the Southern Hemisphere, we observed clear patterns in the population-genetic structure of Prochlorococcus, the most abundant photosynthetic organism on Earth, between and within the three Southern Subtropical Gyres. The same mechanisms that were previously invoked to account for the vertical distribution of ecotypes at local scales accounted for the global (horizontal) patterns we observed. Basin-scale and seasonal variations in the structure and strength of vertical stratification provide a basis for understanding large-scale horizontal distribution in genetic and physiological traits of Prochlorococcus, and perhaps of marine microbial communities in general.

Anesthesia can cause sustained hyperglycemia in C57/BL6J mice

Effects of anesthesia on the blood glucose of C57/BL6J mice were evaluated under conditions commonly used for testing retinal sensitivity with electroretinographic (ERG) recordings. We evaluated the effects of four anesthetics: nembutal (50 mg/kg), pentothal (100 mg/kg), avertin (240 mg/kg), and ketamine/xylazine (100 mg/kg) using saline as control. We measured blood glucose (BG) levels from tail vein blood before and 15 and 60 min following intraperitoneal injections. Fifteen minutes postinjection, all four anesthetics and saline elevated BG with ketamine/xylazine and avertin having substantially greater effects than nembutal, pentothal, and saline. Only the effects of ketamine/xylazine and avertin persisted throughout the test period. Sixty minutes after injecting ketamine/xylazine BG remained elevated at 400 +/- 42 mg/dl, a 167% increase over preinjection levels. Sixty minutes after injecting avertin BG was 288 +/- 10 mg/dl, a 59% increase over preinjection levels. No sustained elevation in BG was detected 60 min following injection of nembutal, pentothal, or saline. Because BG can affect the amplitude of the ERG, caution should be exercised in the use of ketamine/xylazine or avertin. The choice of anesthesia may also be important in diabetes and metabolism research where changes in blood glucose could impact physiological processes.

Cerebral blood flow velocity increases when propofol is changed to desflurane, but not when isoflurane is changed to desflurane in children

BACKGROUND

Children may exhibit delayed emergence following maintenance of anesthesia with propofol or isoflurane. Desflurane is often used towards the end of procedures to facilitate emergence. This study evaluated the effect on middle cerebral artery blood flow velocity (Vmca) in anesthetized children when propofol or isoflurane was substituted with desflurane.

METHODS

Forty-two healthy children aged 1-6 years were enrolled. A standardized anesthetic induction was used. Anesthesia was maintained with remifentanil (0.5 microg.kg(-1) bolus followed by an infusion of 0.2 microg.kg(-1).min(-1)) and a randomly selected sequence of propofol/desflurane/propofol, desflurane/propofol/desflurane, isoflurane/desflurane/isoflurane or desflurane/isoflurane/desflurane. Propofol was administered to maintain a steady-state serum concentration of 3 microg.ml(-1). Desflurane and isoflurane were administered at age-corrected 1 MAC. Hemodynamic stability was maintained. Transcranial Doppler sonography was used to measure Vmca. Hemodynamic variables as well as Vmca were measured 30 min after skin incision and repeated 30 min after each change in anesthetic maintenance agent.

RESULTS

The mean age and weight was 2.3 +/- 1.3 years and 13.0 +/- 3.7 kg, respectively. The Vmca (mean) increased by 35% from 37.7 +/- 10.5 cm s(-1) to 57.8 +/- 14.6 cm s(-1) (P < 0.0001) when propofol was changed to desflurane but was unaffected when desflurane replaced isoflurane.

CONCLUSION

When propofol is changed to desflurane, cerebral blood flow velocity increases significantly in normal children. This cerebral vasodilatory effect may have important implications in the neurosurgical setting.

Urinary tract infection: self-reported incidence and associated costs

PURPOSE

To estimate the annual incidence, cumulative probability of presumed urinary tract infection (UTI) by age, and the social costs.

METHODS

Analysis of a random digit dialing survey of 2000 women in the United States.

RESULTS

10.8 percent (95% CI: 9.4, 12.1%) of women aged 18 and older reported at least one presumed UTI during the past 12 months, with the majority of the cases occurring among women with a history of two or more UTI episodes in their life. We estimate that by age 24, one-third of women will have at least one physician-diagnosed UTI that was treated with prescription medication. Overall, an estimated 11.3 million women in the United States had at least one presumed UTI treated with antibiotics in 1995. We estimate the annual cost of UTI cases with prescriptions to be $1.6 billion in 1995. If the costs occurring after 1995 are discounted at 5% annually, the total cost over 20 years has a present value of $25.5 billion.

CONCLUSION

If a vaccine were developed that would prevent either initial or recurrent UTI the net benefits to society would be substantial, even at a developmental cost of one billion dollars.

Candida vaginitis: self-reported incidence and associated costs

BACKGROUND AND OBJECTIVES

Incidence of Candida vaginitis by age and racial or ethnic group is poorly described.

GOAL

Estimate incidence, cumulative probability of presumed C vaginitis by age, racial or ethnic group, and associated costs.

STUDY DESIGN

Random digit-dialing survey of 2000 US women.

RESULTS

A total of 6.5 percent (95% CI, 5.4-7.5%) of women older than 18 years reported a least one episode of presumed C vaginitis during the previous 2 months. Women reporting a 1-year period with four or more episodes comprised 8.0% of the sample but accounted for 37.2% of women reporting episodes. Black women reported approximately three times more yeast infections in the previous 2 months (17.4%; 95% CI, 11.2-23.5%) than white women (5.8%; 95% CI, 4.7-6.9%).

CONCLUSION

The high incidence and the propensity for recurrence underscore the need for a better understanding of the epidemiology and pathogenesis, and stress the need for the development of more accurate, rapid diagnostics and effective treatments.

The relation between immunoglobulin G antibodies to Chlamydia trachomatis and poor ovarian response to gonadotropin stimulation before in vitro fertilization

OBJECTIVE

To determine whether a relation exists between previous exposure to Chlamydia trachomatis and impaired ovarian response to gonadotropin stimulation.

DESIGN

Controlled clinical study.

SETTING

Two university IVF centers.

PATIENT(S)

Two hundred forty-two patients receiving IVF treatment and 81 control patients. Ninety-four patients with a poor response to IVF, defined by cycle cancellation in response to a daily stimulation dose of 300 IU of FSH, and 148 patients with a good response were matched for age. Twenty-eight pregnant controls and 53 controls of proven fertility also were included.

INTERVENTION(S)

Serum samples were obtained from patients and controls. Serum levels of immunoglobulin (Ig) G antibodies to C. trachomatis were determined by ELISA.

MAIN OUTCOME MEASURE(S)

The prevalence of serum IgG antibodies to C. trachomatis in critically defined poor responders was compared with that of age-matched good responders.

RESULT(S)

A significantly higher proportion of poor responders had serum IgG antibodies to C. trachomatis compared with good responders (44.7% and 30.4%, respectively). Patients undergoing IVF had a significantly higher prevalence of IgG antibodies to C. trachomatis (36%) than did either pregnant or nonpregnant controls (12%).

CONCLUSION(S)

A significantly higher prevalence of serum IgG antibodies to C. trachomatis was observed in critically defined poor responders, suggesting a possible detrimental effect of C. trachomatis on subsequent ovarian function.

Deciphering a neural code for vision

Deciphering the information that eyes, ears, and other sensory organs transmit to the brain is important for understanding the neural basis of behavior. Recordings from single sensory nerve cells have yielded useful insights, but single neurons generally do not mediate behavior; networks of neurons do. Monitoring the activity of all cells in a neural network of a behaving animal, however, is not yet possible. Taking an alternative approach, we used a realistic cell-based model to compute the ensemble of neural activity generated by one sensory organ, the lateral eye of the horseshoe crab, Limulus polyphemus. We studied how the neural network of this eye encodes natural scenes by presenting to the model movies recorded with a video camera mounted above the eye of an animal that was exploring its underwater habitat. Model predictions were confirmed by simultaneously recording responses from single optic nerve fibers of the same animal. We report here that the eye transmits to the brain robust "neural images" of objects having the size, contrast, and motion of potential mates. The neural code for such objects is not found in ambiguous messages of individual optic nerve fibers but rather in patterns of coherent activity that extend over small ensembles of nerve fibers and are bound together by stimulus motion. Integrative properties of neurons in the first synaptic layer of the brain appear well suited to detecting the patterns of coherent activity. Neural coding by this relatively simple eye helps explain how horseshoe crabs find mates and may lead to a better understanding of how more complex sensory organs process information.

Lymphogranuloma venereum: biopsy, serology, and molecular biology

A 21 year old woman presented with painful groin lymphadenopathy and malaise. Lymph node biopsy, to exclude atypical infection and malignancy, suggested the diagnosis of lymphogranuloma venereum. This diagnosis was confirmed by serology and polymerase chain reaction, with the patient subsequently admitting to a casual sexual contact within the United Kingdom. Alternative methods of investigation of this disease are discussed.

Utilization of health services among rural women in Gujarat, India

This study examined the effects of four sets of factors on use of curative health services among rural women living in Gujarat, India. The sets of factors analyzed were as follows: (1) the demographic characteristics of the women; (2) the characteristics of the household in which they lived; (3) the characteristics of the environment in which they lived; and (4) the price and convenience of care. The study focused on rural married women aged 17-45 who had at least one child. Nested multiple logistic regressions were computed on cross-sectional data to assess the simultaneous influences of the independent variables on (1) reports of episodes of illness (2) use of curative services among rural women who reported an illness and (3) use of a specific service. Four types of service were examined as outcomes of interest, namely, private doctors, Aga Khan Health Services centres, government health centres, and traditional healers. Other things being equal, women's education, income, family structure and kinship affiliation were significant predictors of use of service. Women seemed to be more sensitive to travel time to the health service and its associated costs (purdah restrictions, transportation and time costs) than to the direct costs of service. Factors such as women's occupation and sanitation facilities, while associated with use of service in the expected direction, were not significant predictors of use of service. Implications for health planning are offered, including initiatives to implement health promotion and disease prevention programs in addition to increasing access to the existing health services. Avenues for future studies are suggested, particularly in regard to decision-making processes affecting the health-seeking behavior of rural women. It is recommended that such policies and studies should consider the cultural environment in addition to the existing pluralistic health system.

Kinetic characteristics of the erythrocyte sodium-lithium countertransporter in subjects with coronary artery disease

Sodium-lithium countertransport activity, external affinity for sodium (kNa) and maximal rate of turnover (Vmax), were characterized in 21 male subjects (aged 45 to 65 years) with angiographically proven coronary artery disease; these were compared with a matched group of healthy controls. No significant differences in countertransport activity were noted between the coronary artery disease patients and the healthy controls. By contrast, the median [range] kNa in the coronary artery disease group (8.5 [2.6 to 30.5] mmol/L Na) was significantly lower than that in the controls (59.9 [5.9 to 240.5] mmol/L Na; P < .0001). This reduction was accompanied by a significantly lower mean Vmax (controls 0.403 +/- 0.187 v coronary artery disease group 0.248 +/- 0.121 mmol Li/L RBC/h; P < .01). The findings suggest that disturbed behavior of the sodium-lithium countertransporter is not confined to hypertension but may represent a broader-based membrane dysfunction associated with vascular disease.

Increasing the utilization of cost-effective health services through changes in demand

Attaining efficiency in a health care system with a budget constraint involves increasing the utilization of the most cost-effective services. This can be achieved by adjustments to prices, cost curves, or demand curves. In this paper, the potential for demand curve adjustments is examined by selecting two apparently cost-effective services (prenatal care and childhood immunization against tuberculosis), and analyzing the factors explaining their utilization. Data from recent household surveys in Burkina Faso and Niger are used. A multivariate analysis of utilization employs income, price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price variable. Members of certain ethnic groups tend to use the services less, other things being equal. The importance of demand-side factors like ethnicity points to certain kinds of policy interventions like information, education and communication activities which could increase the utilization of cost-effective services.

Ethnic origin and hypertension-associated alterations in sodium-lithium countertransport kinetics

In Caucasian subjects, elevated erythrocyte sodium-lithium countertransport (SLC) activity, displaying an increased affinity for external Na+ (decreased KNa), has a strong association with hypertension and has also been proposed as a potential marker for vascular disease. We have compared SLC activity and the kinetic components, KNa and maximal rate of turnover (Vmax), of the countertransporter in groups of Caucasian, Asian and Black hypertensive subjects matched for ethnicity, age and sex with healthy normotensive controls. SLC activity was the same in all ethnic groups irrespective of the presence of hypertension. Similarly, hypertension had no impact on Vmax values within each ethnic group (normotensive vs. hypertensives: Caucasian, 0.360 +/- 0.186 vs. 0.335 +/- 0.137; Asian, 0.324 +/- 0.078 vs. 0.273 +/- 0.105; black people, 0.192 +/- 0.123 vs. 0.178 +/- 0.082 mmol Li/l erythrocytes h). However, in black people compared with the other two ethnic groups, Vmax was lower for both controls and hypertensives (P < 0.05; ANOVA). Median KNa values in hypertensive subjects were consistently lower than their normotensive counterparts in all ethnic groups (P < 0.01; Kruskal-Wallis); Caucasians, (89.1 vs. 41.2 mmol Na; P = 0.01), Asians (121.1 vs. 33.1; P = 0.04) and black people (74.4 vs. 27.2 mmol Na; P = 0.02; Wilcoxon). The results show that Vmax is altered in black people independently of the presence of hypertension. This contrasts with KNa which, for each ethnic group studied, is reduced in the hypertensive compared with the normotensive state.

Comparison of the binding of nicotinic agonists to receptors from human and rat cerebral cortex and from chick brain (alpha 4 beta 2) transfected into mouse fibroblasts with ion channel activity

(-)-Nicotine, cytisine and carbachol evoked 86Rb efflux from mouse fibroblasts stably transfected with alpha 4 beta 2 chick brain nicotinic subunits. This response to (-)-nicotine was inhibited by mecamylamine and dihydro-beta-erythroidine and was mirrored by a rise in intracellular Ca2+ measured by microspectrofluorimetry. Lobeline and isoarecolone methiodide evoked no significant 86Rb from cells and unlike the above agonists displayed significantly different IC50 values for the displacement of [3H]nicotine from mammalian (rat and human cerebral cortex) and transfected fibroblast membranes.