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At least 1,009 records · Page 56Linked to original sources
PubMed2002

EMLA cream prior to digital nerve block for ingrown nail surgery does not reduce pain at injection of anesthetic solution.

BACKGROUND: Needle penetration and local anesthetic infiltration are painful steps of digital ring block. The objective of this study was to evaluate the efficacy of EMLA cream application prior to digital ring block for surgery for ingrown big toenail. METHODS: We conducted a prospective, double-blinded, placebo-controlled, randomized clinical trial with 81 patients (range: 12-75 years, mean +/- SD: 30.3 +/- 17.5 years), who underwent big toenail surgery. Prior to the digital block, EMLA cream (Group E) or a placebo cream (Group P) was applied. A visual analog scale (VAS) and a verbal rating score (VRS) from 1 to 10, 10 being most severe pain, were used for assessment of pain during the skin needle penetration and during the infiltration of the anesthetic product. RESULTS: Data of the VAS and of the VRS during the two steps, respectively, show no significant difference in pain rating between the two groups. In Group E, the gender of the patients had a significant effect on pain perception. Male patients reported less pain than female patients, both during the needle skin penetration and during the infiltration step (P < 0.005). In Group P, reported pain did not differ by gender in either step of the procedure. CONCLUSIONS: We found no clinical benefit in using EMLA during digital nerve block. Although the digital nerves are not deeply located in the small subcutaneous space of the digit, topical anesthesia may not reach them. Moreover, swelling due to injection of the anesthetic product in this small space may also amplify the sensation of pain.

Adolescent↗
PubMed2001

Why older community-dwelling adults do not discuss urinary incontinence with their primary care physicians.

OBJECTIVES: This study explored reasons why older adults with urinary incontinence (UI) do not initiate discussions with or seek treatment for UI from their primary care provider. DESIGN: A randomized, prospective controlled trial involving 41 primary care sites. SETTING: Primary care practice sites. PARTICIPANTS: 49 older adults age 60 and older not previously screened for UI by their primary care doctor. MEASUREMENTS: Demographic data, self-reported bladder-control information using questionnaires, and health status. RESULTS: Adults who did not discuss UI were older, had less-frequent leaking accidents and fewer nighttime voids and were less bothered by UI than those who did. The two main reasons why patients did not seek help were the perceptions that UI was not a big problem (45%) and was a normal part of aging (19%). CONCLUSIONS: Embarrassment or lack of awareness of treatment options were not significant barriers to discussing UI. Adults with a fairly high frequency of UI (average of 1.7 episodes per day) did not view UI as abnormal or a serious medical condition.

Aged↗
PubMed2004

Ecophysiology of Crassulacean Acid Metabolism (CAM).

BACKGROUND AND SCOPE: Crassulacean Acid Metabolism (CAM) as an ecophysiological modification of photosynthetic carbon acquisition has been reviewed extensively before. Cell biology, enzymology and the flow of carbon along various pathways and through various cellular compartments have been well documented and discussed. The present attempt at reviewing CAM once again tries to use a different approach, considering a wide range of inputs, receivers and outputs. INPUT: Input is given by a network of environmental parameters. Six major ones, CO(2), H(2)O, light, temperature, nutrients and salinity, are considered in detail, which allows discussion of the effects of these factors, and combinations thereof, at the individual plant level ('physiological aut-ecology'). RECEIVERS: Receivers of the environmental cues are the plant types genotypes and phenotypes, the latter including morphotypes and physiotypes. CAM genotypes largely remain 'black boxes', and research endeavours of genomics, producing mutants and following molecular phylogeny, are just beginning. There is no special development of CAM morphotypes except for a strong tendency for leaf or stem succulence with large cells with big vacuoles and often, but not always, special water storage tissues. Various CAM physiotypes with differing degrees of CAM expression are well characterized. OUTPUT: Output is the shaping of habitats, ecosystems and communities by CAM. A number of systems are briefly surveyed, namely aquatic systems, deserts, salinas, savannas, restingas, various types of forests, inselbergs and paramós. CONCLUSIONS: While quantitative census data for CAM diversity and biomass are largely missing, intuition suggests that the larger CAM domains are those systems which are governed by a network of interacting stress factors requiring versatile responses and not systems where a single stress factor strongly prevails. CAM is noted to be a strategy for variable, flexible and plastic niche occupation rather than lush productivity. 'Physiological syn-ecology' reveals that phenotypic plasticity constitutes the ecophysiological advantage of CAM.

Carbon Dioxide↗
PubMedDate not supplied

Mergers and acquisitions report. 1995: a record year for hospital deals.

Healthcare executives whose organizations didn't do anything this year are the odd men out in an industry that made big news almost daily in 1995. The year included not only the usual smattering of mega-mergers but also featured wrongly amputated limbs, more than the normal trade association positioning, and major Medicare and Medicaid reform proposals.

Data Collection↗
PubMed2004

Prevalence of antibodies against hepatitis C virus and hepatitis B coinfection in healthy population in Bulgaria. A seroepidemiological study.

AIM: Viral hepatitis C is often silent and is sometimes discovered only by routine serologic testing. We investigated healthy adults for seroprevalence of antibodies against hepatitis C virus (HCV), for markers of hepatitis B (HBV) coinfection and for risk factors of transmission blood borne viruses. METHODS: We performed a descriptive cross sectional study for the period 1999-2000. A caseload of 2,211 healthy randomly selected subjects (aged 10-69, both sexes) from a big Bulgarian city gave informed consent for participation and answered a standardized questionnaire. Serum samples were obtained and tested using ELISA method for anti-HCV antibodies, HBV markers (HBsAg, anti-HBc and anti-HBs antibodies), as well as for anti-HIV-1.2 antibodies. RESULTS: The overall anti-HCV seroprevalence was 1.08%, which coincides with the data submitted to WHO for the general Bulgarian population, as well as with the average data for Europe. Higher anti-HCV seroprevalence was ascertained with increasing age except in adolescents, in whom the anti-HCV positivity was high. A great part of the subjects with anti-HCV antibodies -- 62.5% had serological evidence for exposure to HBV. Anti-HCV carriage was in positive correlation with the summarized data for previous morbidity (surgery, blood transfusion and past liver disease), as well as with detecting markers for hepatitis B. In the studied caseload 0.68% had markers of double HCV and HBV infection. Nobody was found as seropositive for HIV-1.2. CONCLUSIONS: The results of our study suggest the need of more stringent measures for prevention and control of HCV infection, including screening focused on different groups of population, precise determination of risk factors for HCV transmission and offering of HBV vaccine to HCV positive individuals to reduce the high risk of double HCV and HBV infection.

Adolescent↗
PubMed2006

The coupling of acetylcholine-induced BK channel and calcium channel in guinea pig saccular type II vestibular hair cells.

Molecular biological studies and electrophysiological data have demonstrated that acetylcholine (ACh) is the principal cochlear and vestibular efferent neurotransmitter among mammalians. However, the functional roles of ACh in type II vestibular hair cells (VHCs II) among mammalians are still unclear, with the exception of the well-known alpha9-containing nicotinic ACh receptor (alpha9-containing nAChR)-activated small conductance, calcium-dependent potassium current (SK) in cochlear hair cells and frog saccular hair cells. The activation of SK current was necessary for the calcium influx through the alpha9-containing nAChR. Recently, we have demonstrated that ACh-induced big conductance, calcium-dependent potassium current (BK) was present in VHCs II of the vestibular end-organ of guinea pig. In this study, the nature of calcium influx for the activation of ACh-induced BK current in saccular VHCs II of guinea pig was investigated. Following extracellular perfusion of ACh, saccular VHCs II displayed a sustained outward current, which was sensitive to iberiotoxin (IBTX). High concentration of apamin failed to inhibit the current amplitude of ACh-induced outward current. Intracellular application of Cs(+) completely abolished the current evoked by ACh. ACh-induced current was potently inhibited by nifedipine, nimodipine, Cd(2+) and Ni(2+), respectively. The inhibition potency of these four calcium channel antagonists was nimodipine>nifedipine>cadmium>nickel. The L-type Ca(2+) channels agonist, (-)-Bay-K 8644 mimicked the effect of ACh and activated an IBTX-sensitive current. In addition, partial VHCs II displayed a biphasic waveform. In conclusion, the present data showed that in the guinea pig saccular VHCs II, ACh-induced BK channel was coupled with the calcium channel, but not the receptor. The perfusion of ACh will drive the opening of calcium channels; the influx of calcium ions will then activate the BK current.

Acetylcholine↗
PubMed1998

Coronary constriction and consequent cardiodepression in pulmonary embolism are mediated by pulmonary big endothelin and enhanced in early endothelial dysfunction.

OBJECTIVES: Myocardial ischemia plays a central role in the development of right ventricular failure after acute pulmonary embolism. This study investigates whether pulmonary mediators act specifically on coronary tone and cardiac contractile function in acute pulmonary microembolization and whether such effects are altered in the case of early systemic atherosclerosis. We employ a novel model of serial perfusion in which an isolated rabbit heart is perfused with the effluent of the same animal's isolated lung. DESIGN: Controlled experiment using isolated organs. SETTING: Experimental laboratory. SUBJECTS: Male New Zealand White rabbits (controls). Age-matched, male Watanabe rabbits (hypercholesterolemic, development of accelerated atherosclerosis). INTERVENTIONS: Seven isolated control and seven isolated Watanabe hearts were perfused with the saline effluent of the same animal's isolated lung. After the assessment of the baseline data, the lungs were gradually embolized with glass beads measuring 100 microm in diameter to induce an increase in mean pulmonary arterial pressure from 6 to 8 mm Hg, at baseline, up to 25 mm Hg. MEASUREMENTS AND MAIN RESULTS: Pulmonary embolization to 25 mm Hg evoked a coronary constriction, measured as coronary flow decrease to 89 +/- 7% of the baseline value in controls. In the Watanabe group, coronary constriction was significantly enhanced, compared with controls, with coronary flow decreasing to 76 +/- 6% of the baseline value. In both groups, coronary constriction was followed by a deterioration in cardiac contractile performance. This cardiodepression was significantly deeper in Watanabe hearts with respect to both maximum ventricular pressures and maximum rates of pressure development and decline. Coronary constriction and cardiodepression were prevented by coronary infusion of the nonselective endothelin antagonist PD-145065, the endothelinA antagonists A-127722 and BQ-123, and the endothelin-converting enzyme inhibitor phosphoramidon. Concentration of big endothelin in pulmonary effluent increased from 5.6 +/- 0.3 pmol/L in controls and 5.6 +/- 0.2 pmol/L in the Watanabe group, at baseline, to 8.8 +/- 0.4 pmol/L in controls and 8.9 +/- 0.4 pmol/L in the Watanabe group, at 25 mm Hg pulmonary arterial pressure. Endothelin was not detectable at any time during the experiment in pulmonary effluent. The coronary gradient, calculated as a difference in concentration between coronary and pulmonary effluent, was negative for big endothelin and positive for endothelin in both groups. CONCLUSIONS: We have demonstrated that an increase in pulmonary release of big endothelin occurs during lung embolism, which, in turn, results in coronary constriction and consequent cardiodepression. This action of big endothelin is based on its local coronary conversion into endothelin. In addition, coronary endothelial dysfunction, attributed to early systemic atherosclerosis, was shown to represent a specific risk factor in these events.

6-Ketoprostaglandin F1 alpha↗
PubMed1993

Mimicking of discontinuous epitopes by phage-displayed peptides, I. Epitope mapping of human H ferritin using a phage library of constrained peptides.

We have constructed a random nonapeptide library in the N-terminal region of the major coat protein VIII of bacteriophage f1, with two cysteines flanking the insert, and preliminary data suggest that many of the clones display at least some of their peptides in cyclized form. This library was used to select oligopeptides binding to the monoclonal antibody (mAb) H107, recognising the assembled native conformation of recombinant human H-subunit ferritin (H Fer), whose three-dimensional structure is known. Comparison of the selected oligopeptides with one another allowed us to derive two consensus sequences characterized by conserved amino acid (aa) residues. Analysis of the distribution of the aa side chains exposed on the surface of H Fer reveals that most of the aa defining both consensus sequences are present either at the end of the big loop or at the end of the A helix. These two regions of the H Fer, though separated in the linear sequence, are very close in the folded molecule. Interestingly, each consensus sequence derived from the selected phage-displayed peptides is characterized by aa present both at the end of the big loop and at the end of the A helix. These two H Fer regions are good candidates for mimicry by the selected peptides and therefore for constituting part of the H107 epitope. To provide support to this hypothesis, we constructed several H Fer mutants carrying point mutations in different positions of these two regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed2004

Persistent organochlorine residues in human breast milk from Hanoi and Hochiminh City, Vietnam: contamination, accumulation kinetics and risk assessment for infants.

Despite the ban on persistent organochlorines (OCs) in most of the developed nations, their usage continued until recently in many Asian developing countries including Vietnam, for agricultural purposes and vector-borne disease eradication programs. In this study, we collected human breast milk samples from the two big cities in Vietnam: Hanoi (n=42) and Hochiminh (n=44) and determined the concentrations of persistent OCs such as PCBs, DDT and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs) and tris-4-chlorophenyl-methane (TCPMe). The contamination pattern of OCs was in the order of DDTs > PCBs > HCHs > CHLs approximately HCB approximately TCPMe. Compilation of available data indicated that DDT residue levels in human breast milk from Vietnam were among the highest values reported for Asian developing countries as well as developed nations. This result suggests recent usage of DDTs in both north and south Vietnam. Interestingly, in both cities, the p,p'-DDT portion was higher in multiparas than those in primiparas. Considering the fact that the interval between the first and the second child of a mother in Vietnam is usually short, this result probably indicates continuous intake of DDTs in the population. Analysis of infant exposure to DDTs via breast milk suggested that the daily intake rates for number of individuals are close to or above the threshold for adverse effects which may raise concern on children health.

Age Factors↗
PubMed2001

A new flux-orientated concept to derive critical levels for ozone to protect vegetation.

The current European critical levels for ozone (O3) to protect crops, natural and semi-natural vegetation and forest trees are based on a relative small number of open-top chamber experiments with a very limited number of plant species. Therefore, the working group "Effects of Ozone on Plants" of the Commission on Air Pollution Prevention of the Association of German Engineers and the German Institute of Standardization reanalysed the literature on O3 effects on European plant species published between 1989 and 1999. An exposure-response relationship for wild plant species and agricultural crops could be derived from 30 experiments with more than 30 species and 90 data points; the relationship for conifer and deciduous trees is based on 20 experiments with nine species and 50 data points. From these relationships maximum O3 concentrations for different risk stages are deduced, below which the vegetation type is protected on the basis of the respective criteria. Because it is assumed that the fumigation concentrations reflect the O3 concentrations at the top of the canopy, i.e. the upper surface boundary of the quasi-laminar layer if the micrometeorological big-leaf approach is applied, the application of these maximum O3 concentrations requires the transformation of O3 concentrations measured at a reference height above the canopy to the effective phytotoxic concentrations at the top of the canopy. Thus, the approach described in this paper is a synthesis of the classical concept of toxicology of air pollutants (critical concentrations) and the more toxicological relevant dose concept.

Crops, Agricultural↗
PubMed1988

Assessment of arterial disease using digital systolic pressure measurement.

Digital systolic pressure measurements were made on 140 big toes using a photoplethysmographic technique before and after extrinsic heating of the foot. Most patients with apparent, critically ischemic feet demonstrated vasomotor activity, suggesting that much of the microcirculation of the foot was in fact intact. Significantly, nine of 21 feet which would have fallen into a critically ischemic category were recategorized after heating into a less severe group. These data confirm the value of toe pressure measurements in the assessment of severe ischemia but show that adequate foot vasodilation is essential to allow accurate conclusions to be drawn and to allow meaningful interpretation of results.

Adult↗
PubMed1997

Endothelin converting enzyme (ECE) activity in human vascular smooth muscle.

1. We have characterized the human smooth muscle endothelin converting enzyme (ECE) present in the media of the endothelium-denuded human umbilical vein preparation. 2. Endothelin-1 (ET-1) and ET-2 were potent constrictors of umbilical vein with EC50 values of 9.2 nM and 29.6 nM, respectively. ET-1 was at least 30 times more potent than ET-3 suggesting the presence of constrictor ETA receptors. Little or no response was obtained to the ETB-selective agonist sarafotoxin 6c. These data suggest that endothelin-mediated vasoconstriction is via ETA receptors in this preparation. 3. Autoradiographical visualization of endothelin receptors with subtype selective ligands confirmed the predominance of the ETA receptor in the media of umbilical vein. High density of binding was obtained with the ETA selective [125I]-PD151242, with much lower levels detected with the ETB selective [125I]-BQ3020. 4. Big ET-1 (EC50 = 42.7 nM) and big ET-2(1-38) (EC50 = 99.0 nM) were less potent than ET-1 and ET-2, respectively. Big ET-2(1-38) was more potent than its isoform big ET-2(1-37) with concentration-response curves to big ET-2(1-37) incomplete at 300 nM. No response was obtained to big ET-3 at concentrations up to 700 nM. The C-terminal fragments, big ET-1(22-38) and big ET-2(22-38) were inactive. 5. Responses to ET-1 were unaffected by either the neutral endopeptidase (NEP) inhibitor thiorphan (10(-5) M) or by the dual NEP/ECE inhibitor phosphoramidon (10(-5) M). Big ET-1 was also unaffected by thiorphan but antagonized in a concentration-dependent manner by phosphoramidon (10(-5) M and 10(-4) M). 6. Addition of all four big endothelin peptides to human umbilical vein preparations resulted in detectable amounts of ET-IR in the bathing medium. Therefore, although big ET-3 was functionally inactive this reflects the low potency of ET-3 at the ETA receptor rather than the lack of ability of this smooth muscle ECE to convert big ET-3 to ET-3. 7. To conclude we have demonstrated the presence of a phosphoramidon-sensitive ECE on the smooth muscle layer of the human umbilical vein which can convert big ET-1, big ET-2(1-37), big ET-2(1-38) and big ET-3 to their mature biologically active forms. The precise subcellular localization of this enzyme and its physiological relevance remains to be determined.

Aspartic Acid Endopeptidases↗
PubMed2005

[Retinal angiomatosis].

BACKGROUND: Retinal capillary hemangioblastomas occur sporadically or as one of the manifestations of VHL (von Hippel-Lindau syndrome). In the assessment of retinal hemangioblastomas it is necessary to know about VHL, an autosomal dominant disease, a multisystem familial tumour syndrome. METHODS: An overview of the diagnosis and therapy of VHL is presented. RESULTS: Minimal criteria of the syndrome are tumours in one index patient and one of the typical lesions in another first-degree relative. Retinal hemangioblastomas were already found in children. Only 5 % of patients with VHL present retinal capillary hemangioma before the age of 10 years, and most patients present between the ages of 10 and 40 years. Data suggest that retinal capillary hemangioma is usually manifested by the age of 30 years. The VHL gene functions as a tumour suppressor gene and is mapped to the short arm of chromosome 3p25. The mapping of a locus for VHL has offered the prospect of presymptomatic diagnosis of the disease using DNA markers. Small retinal tumours are treated by photocoagulation, big hemangioblastomas by cryotherapy. Modern options in treatment of retinal tumours are proton therapy, plaque radiotherapy, pars-plana vitrectomy, photodynamic therapy, transpupillary thermotherapy and systemic treatment with the vascular endothelial growth factor (VEGF) receptor inhibitor, in addition. CONCLUSIONS: The interdisciplinary Freiburg VHL study which has been in existence for more than 20 years, has shown that an extensive family screening for early detection of the disease is necessary. The assessment of the diagnosis in a VHL carrier requires close follow-up for multiple and recurrent tumours.

Genetic Testing↗
PubMed1998

Endothelin is an autocrine regulator of prolactin secretion.

The aim of this study was to establish the cellular source of ET-like peptides affecting PRL secretion. Fluorescence double label immunocytochemistry and confocal laser scanning microscopy were used to demonstrate cellular colocalization for PRL and endothelin-1 (ET1)-like immunoreactivities in the anterior lobe of the pituitary gland of rats. An ET-specific reverse hemolytic plaque assay was applied to demonstrate that lactotrophs are capable of releasing ET-like peptides. A PRL-specific reverse hemolytic plaque assay was used to assess the influence of the released endogenous ETs on PRL secretion. ET(A)-specific receptor antagonists BQ123 and BQ610, and endothelin convertase enzyme inhibitory peptide, [22Val]big ET1-(16-38), increased PRL secretion, whereas the ET(B) receptor-specific antagonist BQ788 was ineffective. The ET(A) antagonist BQ123-induced increase in PRL secretion followed a bell-shaped dose-response curve in cells obtained from female rats, whereas it followed a sigmoid curve in males. Frequency distribution of PRL plaque sizes using logarithmically binned data revealed two subpopulations of lactotrophs with differential responsiveness to endogenous ETs. These data demonstrate that a large proportion of lactotrophs is capable of expressing and secreting ET-like peptides in biologically significant quantities. As low pituitary cell density in reverse hemolytic plaque assay minimizes cell to cell communications, these findings constitute direct proof of autocrine regulation of PRL secretion by ET-like peptides.

Animals↗
PubMed2001

[Epidemiology of HBV infections and possibilities for therapeutic actions in children and adolescents with end-stage renal failure treated with dialysis].

Wide spreading of prophylaxis principles of HBV infections in dialysis centers decreased the HBV infection rate in general population of dialyzed patients in Poland last years. There is neither data concerned with HBV infection epidemiology in children and adolescents, nor data about anti-viral treatment possibilities and effects in this group of dialyzed patients. The aim of the study was evaluating of HBV infection rate in patients of pediatric dialysis centers and analysis of causes of infection and efficacy of treatment. Study was based on data sent in a query-answer by 8 biggest pediatric dialysis centers, all of them treating 210 patients. HBV infection was found much more often (16.6%) than in population of all hemodialyzed patients in Poland. More than 75% non-vaccinated patients was infected before dialysis therapy, remaining were infected during vaccination, before the protecting level of antibodies was gained. Big differences in HBV infection rate among centers are observed. Nowadays HCV infections (more than 40% patients infected) are a bigger issue. Only 10 patients in 5 centers had anti-viral treatment (5 with isolated HBV infection, 5 with mixed HBV/HCV infection). In 9 patients interferon-alpha and in 1 patient lamivudine was administered. Efficacy of interferon-alpha treatment was similar to the population of non-uremic children (33.3% vs. 50% of HBeAg elimination). Majority of patients quite well tolerated the drug. Only in 1 case interferon-alpha treatment had to be ceased because of side effects. In a boy treated with lamivudine, after 3 months elimination of viremia and decrease of ALAT activity was observed. HBV infection in patients of pediatric dialysis centers is still a serious matter. More strict applying of vaccination against hepatitis B before dialysis treatment is needed. The possibility of HBV infections therapy is limited, mostly for economical reasons.

Adolescent↗
PubMed2003

[Seminal profile in workers exposed to cholinesterase inhibitor insecticides].

The objective of this study was to determine the physical, chemical and cytomorphologic characteristics of semen obtained from workers exposed to cholinesterase inhibitor insecticides and compare them with samples of the same nature obtained from unexposed subjects, and in addition, to correlate those findings with blood levels of cholinesterase. The study group consisted of 29 adult males, age range 20-54, that were exposed to cholinesterase inhibitor insecticides during 4 hours per day for a variable lapse (one year minimum), whereas the control group consisted of 30 unexposed individuals of the same gender, and similar age range. A thorough medical examination was performed in every individual. It consisted of an occupational medical history and complete physical exam. A blood sample was obtained in all the subjects in order to determine total cholinesterase levels by the modified S. Hestrin Hydroxamate method. Semen analysis was done in specimens collected after recent masturbation following a 3-day abstinence period. The data was processed and analyzed by the SAS computerized statistics program. The results revealed significant differences between both groups (p < 0.05) for the following variables: sperm count per mL., percentage of fast, mobile and immobile, live and dead spermatozoids. Spermatozoa morphology was found to be within normal limits as established by the WHO. Nevertheless, the differences related to the percentage of big head and amorphous spermatozoids was significant (p < 0.05). The results indicate that cholinesterase inhibitor insecticides affect certain variables of the semen analysis and hence the quality of the semen.

Adult↗
PubMed1997

Anti-tuberculosis drug resistance in Madagascar in 1994-1995.

SETTING: A new tuberculosis control programme has been implemented in Madagascar since 1991. A survey on Mycobacterium tuberculosis resistance to the major drugs was conducted between August 1994 and December 1995. OBJECTIVE: To determine primary and acquired resistance in pulmonary tuberculosis patients in four main cities. DESIGN: Were included 401 randomly sampled new smear positive patients (36.2% of declared new patients) and 137 recurrent cases (72.9% of declared cases) from 8 centres. Drug susceptibility testing was performed on Löwenstein Jensen medium according to the proportion method. RESULTS: The male to female ratio was 1.35:1 in new patients (age range 11-74 years) and 1.98:1 in recurrent patients (age range 16-76 years). The primary resistance rate to any drug was 20% (95% Confidence Interval [CI] 16-23) and the acquired resistance rate 40% (95% CI 32-48, P < 2.10(-7). Primary resistance to one drug was 18% (95% CI 15-22), mainly attributable to streptomycin resistance (14.5%). Multidrug resistance (MDR) to isoniazid and rifampicin was 0.25% (95% CI 0-0.7) for primary resistance and 5% (95% CI 2.6-10.6) for secondary resistance. No difference was observed between sexes or ages. CONCLUSION: This survey conducted in big cities gives a very negative picture of resistance in Madagascar.

Adolescent↗
PubMed1993

Tonotopic and functional organization in the auditory cortex of the big brown bat, Eptesicus fuscus.

1. In Eptesicus the auditory cortex, as defined by electrical activity recorded from microelectrodes in response to tone bursts, FM sweeps, and combinations of FM sweeps, encompasses an average cortical surface area of 5.7 mm2. This area is large with respect to the total cortical surface area and reflects the importance of auditory processing to this species of bat. 2. The predominant pattern of organization in response to tone bursts observed in each cortex is tonotopic, with three discernible divisions revealed by our data. However, although cortical best-frequency (BF) maps from most of the individual bats are similar, no two maps are identical. The largest division contains an average of 84% of the auditory cortical surface area, with BF tonotopically mapped from high to low along the anteroposterior axis and is part of the primary auditory cortex. The medium division encompasses an average of 13% of the auditory cortical surface area, with highly variable BF organization across bats. The third region is the smallest, with an average of only 3% of auditory cortical surface area and is located at the anterolateral edge of the cortex. This region is marked by a reversal of the tonotopic axis and a restriction in the range of BFs as compared with the larger, tonotopically organized division. 3. A population of cortical neurons was found (n = 39) in which each neuron exhibited two BF threshold minima (BF1 and BF2) in response to tone bursts. These neurons thus have multipeaked frequency threshold tuning curves. In Eptesicus the majority of multipeaked frequency-tuned neurons (n = 27) have threshold minima at frequencies that correspond to a harmonic ratio of three-to-one. In contrast, the majority of multipeaked neurons in cats have threshold minima at frequencies in a ratio of three-to-two. A three-to-one harmonic ratio corresponds to the "spectral notches" produced by interference between overlapping echoes from multiple reflective surfaces in complex sonar targets. Behavioral experiments have demonstrated the ability of Eptesicus to use spectral interference notches for perceiving target shape, and this subpopulation of multipeaked frequency-tuned neurons may be involved in coding of spectral notches. 4. The auditory cortex contains delay-tuned neurons that encode target range (n = 99). Most delay-tuned neurons respond poorly to tones or individual FM sweeps and require combinations of FM sweeps. They are combination sensitive and delay tuned.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗