Differential parallel processing of olfactory information in the honeybee, Apis mellifera L

Two distinct neuronal pathways connect the first olfactory neuropil, the antennal lobe, with higher integration areas, such as the mushroom bodies, via antennal lobe projection neurons. Intracellular recordings were used to address the question whether neuroanatomical features affect odor-coding properties. We found that neurons in the median antennocerebral tract code odors by latency differences or specific inhibitory phases in combination with excitatory phases, have a more specific activity profile for different odors and convey the information with a delay. The neurons of the lateral antennocerebral tract code odors by spike rate differences, have a broader activity profile for different odors, and convey the information quickly. Thus, rather preliminary information about the olfactory stimulus first reaches the mushroom bodies and the lateral horn via neurons of the lateral antennocerebral tract and subsequently odor information becomes more specified by activities of neurons of the median antennocerebral tract. We conclude that this neuroanatomical feature is not related to the distinction between different odors, but rather reflects a dual coding of the same odor stimuli by two different neuronal strategies focusing different properties of the same stimulus.

[Poorly tolerated or genuinely allergic? How to properly assess food allergies]

Massive immune reactions to certain foods may be traced back to immunological, but also to non-immunological mechanisms. The diagnostic work-up must therefore aim to distinguish an allergy from other inflammatory, neoplastic or immunoregulative disorders. The most common form of gastrointestinal-mediated allergy form are the IgE-mediated reactions of the immediate type (Type 1 allergy). The routine diagnostic investigation includes history-taking, a daily diary of foods eaten, skin tests and antibody determination. The diagnosis of an allergy is often complicated by the multitude of possible manifestation sites, a possibly localized effect, and variations in the depth of allergic processes. To confirm the diagnosis, an oral provocative test should always be performed.

Gait analysis on the treadmill - monitoring exercise in the treatment of paraplegia

STUDY DESIGN

A prospective study was performed to evaluate the gait training of seven consecutive spinal cord injured patients and 10 controls on a treadmill using instrumented gait analysis and video documentation.

OBJECTIVES

To determine whether it is possible to maintain gait motion within physiological limits during treadmill training.

SETTING

Primary and secondary care unit for spinal cord injury, Heidelberg, Germany.

METHODS

Treadmill training was instituted as early as possible. Gait analysis was performed when the patients were stable enough to walk without manual aid from therapists and enough endurance to allow measurements. A control group of healthy volunteers were examined as well. Video documentation and a camera system using passive markers were employed.

RESULTS

Treadmill training started with weight reduction of 25% of bodyweight (18 (0-35) kg), maximum walking speed 0.28 (0.15-0.7) m/s and maximum walking duration 4.7 (3-7) min. At the end of the training, weight reduction decreased to 9.3 (0-20) kg, maximum walking speed increased to 0.67 (0.23-1.1) ms with a maximum walking duration of 11 (8-15) min. 3-D motion analysis of hip, knee and ankle demonstrated joint excursions almost entirely within the limits of normal gait. Exceptions were due to fixed contractures.

CONCLUSIONS

Our data suggests that it is possible to perform early gait training on a treadmill with no supportive orthoses within the physiologic range of joint motion. The risk for repetitive stress injuries or other negative effects is low.

Tissue and serum concentrations of levofloxacin in orthopaedic patients

The level of levofloxacin was determined in serum, bone and several tissues after a single dose of 500 mg i.v. Twenty-one patients (mean age: 56.8 years) undergoing bone surgery (nine patients) or surgical debridement of a decubitus ulcer (12 patients) who received levofloxacin as perioperative prophylaxis were included in the study. During surgery, blood and tissue samples were obtained approximately 1.5 h (range 40-210 min) postdosing. Levofloxacin concentrations in 87 specimens including 21 serum samples were determined using high-performance liquid chromatography (HPLC). The mean serum concentration at 1.5 h was 8.6+/-2.3 microg/ml. Concentrations above the MIC of common pathogens were reached in all tissues during the collection period with a maximum in skin samples (19.9+/-9.9 microg/g) followed by wound tissue and granulation tissue with 17.3+/-6.5 and 13.7+/-6.4 microg/g respectively. In muscle and fatty tissue mean levofloxacin concentrations of 8.0+/-0.9 and 4.0+/-2.2 microg/g were attained. Mean levels in cancellous bone were 6.6+/-3.6 microg/g, lowest levels were measured in cortical bone (2.8+/-1.1 microg/g). Twenty-two different pathogens were cultivated from the lesions of 11 of 12 patients with pressure ulcers. MIC values for levofloxacin were determined and compared with the corresponding tissue concentrations. Levofloxacin may be useful for perioperative prophylaxis and treatment in orthopaedic patients due to its good tissue penetration.

Drug interactions with clinafloxacin

Many fluoroquinolone antibiotics are inhibitors of cytochrome P450 enzyme systems and may produce potentially important drug interactions when administered with other drugs. Studies were conducted to determine the effect of clinafloxacin on the pharmacokinetics of theophylline, caffeine, warfarin, and phenytoin, as well as the effect of phenytoin on the pharmacokinetics of clinafloxacin. Concomitant administration of 200 or 400 mg of clinafloxacin reduces mean theophylline clearance by approximately 50 and 70%, respectively, and reduces mean caffeine clearance by 84%. (R)-Warfarin concentrations in plasma during clinafloxacin administration are 32% higher and (S)-warfarin concentrations do not change during clinafloxacin treatment. An observed late pharmacodynamic effect was most likely due to gut flora changes. Phenytoin has no effect on clinafloxacin pharmacokinetics, while phenytoin clearance is 15% lower during clinafloxacin administration.

Clinafloxacin pharmacokinetics in subjects with various degrees of renal function

As the primary route for elimination of clinafloxacin is renal clearance (CL(R)) of unchanged drug, studies were conducted to determine the pharmacokinetic profile of clinafloxacin following administration to young and elderly subjects, subjects with various degrees of renal function, and subjects requiring dialysis. These were open-label studies in which subjects received single oral clinafloxacin doses. Sixteen young subjects (18 to 35 years old) and 16 elderly subjects (>65 years old) were enrolled in a study comparing pharmacokinetic profiles of clinafloxacin in young and elderly subjects. Twenty subjects having various degrees of renal function were enrolled into one of three groups based on degree of renal function as measured by creatinine clearance (CL(CR)). Twelve subjects with severe renal impairment requiring dialysis enrolled in a third study. Clinafloxacin was generally well tolerated by all subjects. Clinafloxacin pharmacokinetic profiles in elderly subjects were dependent only on age-related decreases in renal function. Clinafloxacin maximum concentrations in plasma, areas under the concentration-time curves, and terminal elimination half-life values increased with decreasing CL(CR) values. Total apparent body clearance of clinafloxacin from the plasma after oral administration (CL(oral)) and CL(R) were dependent on CL(CR) according to the following relationships: CL(oral) = 2.3. CL(CR) + 77 and CL(R) = 1.74. CL(CR). Hemodialysis had no significant effect on clinafloxacin clearance. Based on the relationship between CL(CR) and clinafloxacin CL(oral) and CL(R) values, the clinafloxacin dose should be halved in patients having a CL(CR) of <40 ml/min. Further dose adjustment is not warranted in patients requiring hemodialysis.

Structure and response patterns of olfactory interneurons in the honeybee, Apis mellifera

To analyze morphologic and physiological properties of olfactory interneurons in the honeybee, Apis mellifera, antennal lobe (AL) neurons were intracellularly recorded and subsequently labeled with Neurobiotin. Additional focal injections were carried out with cobalt hexamine chloride and dextran fluorescent markers. Olfactory interneurons (projection neurons, PNs) project by means of five tracts, the lateral, the median, and three mediolateral antennocerebral tracts (l-, m-, and ml-ACT, respectively) to the mushroom bodies (MBs) and the protocerebral lobe (PL) of the ipsilateral protocerebrum. Uniglomerular PNs of the m- and l-ACT receiving input from a single glomerulus of the AL also arborize in different regions of the AL. The vast majority of l-ACT innervate the T1 region, whereas m-ACT neurons arborize exclusively in the T2, T3, and T4 regions (T1-4 : AL projection area of sensory cells from the antennae). In the calyces of the MB, uniglomerular PNs form varicosities in the basal ring and the lip region. Individual neurons of both types exhibit unequal innervation within and between the two calyces. In addition, m-ACT fibers ramify more densely within the lip neuropil and show a higher incidence of spine-like processes than l-ACTs. In the PL, l-ACTs arborize exclusively within the lateral horn, whereas some m-ACT neurons innervate a broader region. Multiglomerular neurons of the ml-ACT leave the AL by means of three subtracts (ml-ACT 1-3). Two different types can be distinguished according to their protocerebral target areas: ml-ACTs projecting to the lateral PL (LPL) and to the neuropil around the alpha-lobe (tracts 2 and 3) and neurons projecting only to the LPL (tract 1). Intracellular recordings indicate that both l- and m-ACT neurons respond to general odors but with different response properties, indicating that odor information is processed in parallel pathways with different functional characteristics. Just like m-ACT neurons, ml-ACT neurons respond to odors with complex activity patterns. Bilateral interneurons, originating in the suboesophageal ganglion, connect glomeruli of both AL, and send an axon through the m-ACT in each hemisphere of the brain, terminating in the lip region of the calyces. These neurons respond to contact chemical stimuli.

Prevalence of anaemia and iron deficiency in three trimesters in Rural Vellore district, South India

A multistage sampling technique was used to select 845 pregnant women from two blocks in Vellore district. Haematological measurement of haemoglobin (Hb) was done on all women and serum ferritin (SF) on a subsample of 445. The prevalence of anaemia (Hb <11 g/dl) was 56.6%, 70.2% and 69.5%, respectively among the first, second and third trimester women. The mean Hb of 10.7 g/dl was significantly higher among the first trimester than among the second and third trimester women, which was less than the recommended value of 11 g/dl. Iron deficiency (SF <12 microg/L) was significantly (P< 0.05) more among the third trimester women than among the first. The high prevalence of anaemia in each trimester in pregnancy indicates the need for iron supplementation as early as possible starting from the fourth month of pregnancy.

[Amputation of the lower extremity in paraplegic patients. Etiology, sequelae and patient management]

Up to now, there are not many reports about indications and guidelines for prosthetic fitting in amputated paraplegics and tetraplegics. In a review of 35 spinal cord patients with 42 amputations of the lower extremity, data on the neurological level, cause of injury, level of amputation, long-term complications, prosthetic fitting, and usage of the prostheses in daily life are presented. Everyday usage of the prostheses is reported for 15 patients.

Maternal anaemia: a persistent problem in rural Tamil Nadu

BACKGROUND

The incidence of maternal anaemia continues to be high (over 70%) in India in spite of a major nationwide intervention programme. This study was carried out in June 1996 on a representative sample of pregnant women from K.V. Kuppam and Gudiyatham blocks of Vellore district, Tamil Nadu, India.

METHODS

Haemoglobin (Hb) estimations were done in a sample of 895 pregnant women in both the blocks while serum ferritin (SF) levels were estimated on a subsample of 445 pregnant women.

RESULTS

The prevalence of maternal anaemia (Hb < 11 g/dl) was 69.3% (35.8% moderately anaemic, 30.2% mildly anaemic and 3.3% severely anaemic). The mean Hb was 10.1 g/dl. Prevalence of iron deficiency was 36.3% [SF < 12 micrograms/L, mean SF 24.3 micrograms/L (range: 1.5-153 micrograms/L)]. Iron deficiency anaemia as defined by Hb < 11 g/dl and SF < 12 micrograms/L was 29.5%.

CONCLUSION

The prevalence of maternal anaemia and iron deficiency anaemia continues to be high in spite of planned interventions implemented at the national level.

Can iron status be improved in each of the three trimesters? A community-based study

OBJECTIVE

Intervention with iron supplementation, deworming, and information, education and communication (IEC) to improve the haematological status among each of the three trimesters of pregnant women in a rural community.

DESIGN

A community-based study was carried out using a two-group pre-post experimental design in a rural community.

SETTING

Two rural blocks in Vellore district were selected for the study. KV Kuppam block with a population of 120,000 and the adjacent Gudiyatham block with a population of 132,000 served as study and control areas for the study.

SUBJECTS

Using a multistage sampling, initially 50% of the panchayats, the local village administrative units, were randomly selected and all pregnant women were the subjects. In the pre-intervention survey 458 and 387 pregnant women had haemoglobin tested and the post-intervention survey covered 403 and 425 pregnant women in the study and control areas, respectively. Similarly serum ferritin was tested in a randomly selected sub-sample with 254 and 191 pregnant women before intervention and in 216 and 223 pregnant women after intervention in both study and control areas, respectively.

INTERVENTION

Iron supplementation and deworming were provided to all pregnant women in the study area from the fourth month of their pregnancy. An intensive information, education and communication was carried out with facts on anaemia and diet modification to each pregnant woman, using a one-to-one approach in the community, and a group method in the mobile clinics. This was carried out for a period of 18 months.

RESULTS

A significant decrease in the prevalence of anaemia was found, from 56.1% to 25.07% (P<0.001), 73. 4% to 49.2% (P<0.001) and 68.8% to 56.8% (P<0.01) among women in the first, second and third trimesters, respectively, in the intervention area. Significant (P<0.001) increases in the mean haemoglobin of 0.85 g/dl (95% CI 10.18-10.84, 11.09-11.63), 0.59 g/dl (95% CI 9.98-10.34, 10.55-10.95) and 0.36 g/dl (95% CI 9.93-10. 33, 10.25-10.73) were also observed in each of the groups.

CONCLUSION

A comprehensive community-based intervention with iron supplementation, helminthic treatment and increase in knowledge using IEC through effective strategies can improve the haematological status of pregnant women in each trimester.

Effect of food on the pharmacodynamics and pharmacokinetics of atorvastatin, an inhibitor of HMG-CoA reductase

The pharmacodynamics and pharmacokinetics of atorvastatin, an HMG-CoA reductase inhibitor, were characterized in 16 healthy subjects following administration of 10 mg atorvastatin tablets with, or 3 h after, evening meals for 15 days in an open-label, randomized, 2-way crossover study. Atorvastatin was well tolerated. Atorvastatin administration with evening meals resulted in 25.2% lower mean Cmax and 29.8% longer mean tmax values relative to administration after meals. The mean AUC(0-24) value was 8.6% lower for atorvastatin administration with meals compared to after meals. In contrast to the effect of food on pharmacokinetics, LDL-C reductions were similar after atorvastatin administration with or after evening meals. Average reductions from baseline were 24.4% for total cholesterol, 39.6% for LDL-C and 10% for triglycerides. Therefore, atorvastatin may be administered with or without food.

Dietary vitamin A intakes of preschool-age children in South India

The vitamin A intake of children aged 1-3 y (n = 683) was assessed using a quantitative food-frequency questionnaire in a vitamin A intervention study in South India. Trained field workers interviewed mothers about their children's usual consumption of common sources of vitamin A and collected information on portion sizes using standard cups. Mothers were asked to state the number of months in a year during which specific seasonal foods were available. Information about current breast-feeding was also obtained. Vitamin A intakes from nonbreast milk sources were extremely low at all ages. The median intake of total vitamin A, beta-carotene and retinol was 121, 100 and 21 retinol equivalents (RE), respectively. Maternal education and socioeconomic status (SES) were positively associated with total vitamin A and retinol intakes. Girls had significantly lower intakes than boys even after adjusting for differences in age, maternal education, SES and breast-feeding status. Breast-feeding was common, but declined to 60% by 24 mo and to 15% by 36 mo. Vitamin A intakes from nonbreast milk sources increased with age only for currently breast-fed children, who tended to be of lower SES. After taking into account the potential contribution of breast milk by using published estimates, nonbreast-fed children met only 60% of the Indian recommended dietary allowance (RDA; 250 RE/d), whereas breast-fed children met approximately 90% of the RDA during y 2 of life.

Heterotopic pancreas as lead point in intussusception: new variant of vitellointestinal tract malformation

Two cases of intussusception are reported with heterotopic pancreatic tissue attached to and draining into the ileum. The first patient, a boy aged 16 months, presented with ileoileal intussusception. The diagnosis was confirmed on ultrasound scan. Laparotomy and resection were performed. A 12-mm nodule of heterotopic pancreatic tissue was identified in the ileal serosa at the apex of the intussusceptum, fully formed with acinar tissue, islets, and draining duct. The second patient, also a boy aged 16 months, presented with obstructed ileocolic intussusception in which the lead point at surgery resembled a Meckel's diverticulum. Histopathology revealed a similar 10-mm nodule of fully formed pancreatic tissue in the ileal serosal tissues, with some acinar tissue extending through the wall of the intestine alongside ductal structures. In both cases there was ectopic gastric mucosa either in the distal part of the draining duct or in the small intestine itself at the opening. Heterotopic pancreas is a rare cause of intussusception. We propose that this lesion is of vitellointestinal tract origin, conceptually similar to a Meckel's diverticulum but without a diverticulum as such. Heterotopic pancreatic tissue occurring alone is more common in the proximal small intestine, duodenum, and stomach than in the ileum, and it is often asymptomatic.

Is knowledge of leprosy adequate among teachers? A comparative study

A cross-sectional comparative study on the levels of knowledge and attitude on leprosy among teachers and students was carried out in a rural area of Vellore district in Tamil Nadu, India. A total of 30 teachers and 120 students participated in the study. It was found that knowledge about leprosy among teachers was inadequate. Only 23.4% of teachers stated that germs caused leprosy, while 23.4% mentioned immoral conduct, 20.0% marrying a leprosy patient, 6.6% insects and 26.6% did not know the causes of leprosy. While 80.0% of teachers knew that anaesthetic hypopigmented patches were a sign of leprosy, enlarged painful nerves were not mentioned by a single teacher, although this sign was identified by 17.5% of students. Teachers had a more positive attitude towards leprosy than students and this was statistically significant (p < 0.001). This paper discusses the need for continuous education, especially for teachers and through them the students, using different media so as to ensure sustained knowledge for behavioural change in the community.

Residual deformity of the spinal canal in patients with traumatic paraplegia and secondary changes of the spinal cord

INTRODUCTION

The effect of spinal deformity with posttraumatic kyphosis and stenosis of the spinal canal in producing secondary changes of the spinal cord has been discussed for quite some time. Since the advent of magnetic resonance imaging (MRI), 20-40% of patients with posttraumatic paraplegia are found to develop hydromyelia. PURPOSE OF OUR STUDY: To evaluate the influence of residual spinal deformity, defined by the extent of the posttraumatic kyphosis and stenosis, in the development of posttraumatic hydromyelia.

MATERIAL AND METHODS

Two hundred and seven cases of traumatic paraplegia with MRI follow-up were reviewed retrospectively. A minimum of 3 years duration between trauma and MRI study was required (mean 10.6 years [3.2-38.3]). For statistical analysis two groups of patients were formed: with hydromyelia and without hydromyelia. After healing of the fracture, the extent of the kyphosis and stenosis, as well as the characteristics of the paraplegia were noted.

RESULTS

We found that 53 patients had hydromyelia. A highly significant correlation was found for the extent of spinal stenosis and the amount of kyphosis. Cluster analysis indicated that patients with more than 15 degrees of posttraumatic kyphosis and more than 25% of stenosis were twice as likely to develop hydromyelia. The level of the lesion and the remaining neurological function was not proven to have any influence towards the development of hydromyelia.

CONCLUSIONS

These results support the idea that chronic mechanical stress to the spinal cord increases the risk for the development of hydromyelia. Surgical reconstruction should be considered for all patients to prevent secondary changes of the spinal cord.

Tamil Nadu nutritional survey comparing children aged 0-3 years with the NCHS/CDC reference population

A cross-sectional nutritional survey of children belonging to Tamil Nadu State of India, aged 0-3 years was conducted on a representative sample of 2039 children. The collected data was analysed using the recommended indices of height-for-age and weight-for-height based on standard deviation (SD scores) and cross-classified using the SD scores. The nutritional status of these children was compared with the NCHS standard. Prevalence of stunting (27.6%), wasting (9.9%) and simultaneous wasting and stunting (10.7%) was high among the children studied.

A study of chest radiography with mobile X-ray units

A survey of radiographic technique and estimated entrance surface dose has been carried out for 364 chest radiographs performed with mobile X-ray equipment in the Intensive Therapy Unit (ITU) and 30 wards at Aberdeen Royal Infirmary. Data for these two types of location were compared, as were those for two film/screen systems used on the wards. Image quality assessments were made on sets of radiographs for two patients. Entrance skin doses for chest radiographs performed in the ITU were 50% greater than on the wards with the same film/screen system. The main technique difference was the use of shorter focus-to-skin distances (FSDs) in ITU. Doses with the Kodak Insight system were 20% higher than those using Du Pont Quanta III in similar locations. No correlation was found between image quality and entrance surface dose (ESD). Results from the survey were used to recommend exposure factors for shorter FSDs. A follow-up study revealed a 35-45% reduction in ESD for Kodak Insight and a 20% reduction for Quanta III.