Types E1 Research Articles

Efficiency of the decision support system for determining the severity of scoliotic spinal deformity by the analysis of radiographs

BACKGROUND: In 2020, a decision support system was developed at expense of grant from Innovation Promotion Fund and integrated into medical base of prosthetic and orthopedic center “Sсoliologic.ru.” It is the first computer program for determining severity of scoliotic spinal deformity in analysis of radiographs. AIM: To evaluate performance of a computer program for determining Cobb angle by comparing obtained automated data with manual measurement data by various specialists. MATERIALS AND METHODS: From medical base of prosthetic and orthopedic center “Sсoliologic.ru,” 411 digital radiographs of spine of children and adolescents were selected, which were drawn by a radiologist (BP-etalon), an orthopedic traumatologist with 5 years of experience and experience in vertebrology (OO), and an orthopedic traumatologist with less than 1 year of experience and no experience in vertebrology (OB) and computer program (KP). The number and proportion of exact matches and mean absolute percentage error (MAPE) of results of measuring the Cobb angle of reference data were compared with indicators obtained by OO, OB, and KP in, for various types of scoliosis according to the classification of Rigо, as well as in determining the main arc. Bland–Altman graphs were used. The mean absolute deviation (MAD) and MAPE for the main arc with magnitude ranging from 20° to 50° were calculated. RESULTS: The exact matches of KP with standard were 21%. Hence, every fifth measurement of the Cobb angle on X-ray, calculated automatically, was identical to standard. The highest proportion of matches with standard was noted in OO (33%), and the lowest in OB (16%). The highest accuracy of KP was found at types E1 and E2, and the arc of 3 was 30% and 24%, respectively. The proportion of KP matches with standard increased to 61%, with an error of 3°, and to 75%, with an error of 5°; with an error of 7°, the proportion of matches reached 84%. Moreover, the proportion of coincidences of a non-experienced researcher increased from 34% to 58%. When determining magnitude of the main arc of scoliosis, OO increased his/her accuracy by almost 2,6 times, KP by 2,1 times, and OB by 1,5 times. The MAD of KP for all major arcs was 3.8°. Good reliability of the obtained KP indicators compared to the reference (ICC = 0.9) was noted. CONCLUSIONS: The use of a computer program may be recommended for automated determination of Cobb angle, because current algorithm of computer program has been found to be accurate compared to reference measurement. Its accuracy was significantly higher than that of novice orthopedic traumatologists with no experience in vertebrology.

Bile Duct Injury in Laparoscopic Cholecystectomy; A Multi Centre Experience

Background: Laparoscopic cholecystectomy (LC), a minimally invasive gallbladder removal surgery, has revolutionized the field with benefits like quicker recovery. However, it is not without risks, and bile duct injury (BDI) is a severe but rare complication. BDI incidence during LC varies (0.4%-0.9%), with potentially life-threatening consequences. Surgeon experience, intraoperative cholangiography, and careful handling are crucial in preventing and managing BDIs. Aim of the study: This study aims to present and analyze a Multi centre experience regarding the management of these bile duct injuries in LC. Methods: This retrospective study, conducted at UAE medical institutions from 2014 to 2024, analyzed 2400 Laparoscopic Cholecystectomy surgeries over ten years. Out of 18 patients, thirteen patients were treated with ERCP, while five required additional surgery. Inclusion criteria involved patients aged 30 to 70+, of both genders, with BDIs. Exclusion criteria included minor BDIs and comorbidities. Two diagnostic techniques, including intraoperative cholangiography and postoperative assessments, identified BDIs. Treatment varied based on Strasberg classification, involving suturing, ERCP, stent placement, and Roux-en-Y hepaticojejunostomy. Data analysis employed SPSS, presenting results through tables and graphs with statistical parameters. Result: The study focused on Laparoscopic Cholecystectomy-related Bile Duct Injuries (BDI), with a cohort primarily aged 51-70 (66.67%). This age group showed higher susceptibility to BDI. The average participant age was 55.21±12.54 years, with a male majority (55.56%). Among 18 Endoscopic Retrograde Cholangiopancreatography (ERCP) cases, five had BDI, diagnosed intra/postoperatively. Two patients with clinical symptoms had postoperative diagnosis through Percutaneous Transhepatic Cholangiography (PTC). Strasberg classification revealed 60% Type A injuries; Types E1 and E2 each constituted 20%. Treatment modalities varied, with ERCP for Type A injuries (60%) and Roux-en-Y Hepaticojejunostomy (RYHJ) for Types E1 and E2. Conclusion: ERCP is a valuable method for diagnosing and managing Bile Duct Injuries (BDIs). The predominant type of BDIs, specifically Type A, is typically diagnosed after surgery. ERCP demonstrates its efficacy in addressing the majority of Strasberg Type A BDIs. In substantial and intricate BDIs, the Roux-en-Y Hepaticojejunostomy is a secure and efficient approach.

Mapping Climate Classification of Oldeman in Agricultural Resources Management in South Tapanuli District

The Oldeman classification system is very useful in the classification of agricultural land for food crops in Indonesia using the element of rainfall. The criteria are based on the calculation of wet months (BB) and dry months (BK), respectively, with the limits taking into account the chance of rain, effective rain and water requirements for plants. With the Oldeman climate classification, a cropping pattern system can be determined in an area. Based on the research results obtained 4 types of climate in the South Tapanuli region, namely: D1, D2, E1, and E2. The wettest climate type in the Sipirok region is climate type D1 with 4-5 wet months and ,2 dry months. And those that are suitable for planting short-lived rice are 3 (three) harvests or short-lived rice is 2 (two) harvests and secondary crops 1 (sastu) harvests. The driest climate types in the East Angkola region are climate types E1 and E2 with the number of wet months ,3 and the number of dry months 6-7. What is suitable for planting short-lived lowland rice is 1 (one) harvest and secondary crops 2 (two) times, the second special harvest falls in the dry season. The topographical condition of an area greatly influences the climatic conditions of the area. With a good climate classification and suitable for rice plants without irrigation assistance, the climate types are D1 and D2, namely in Sipirok District, West Angkola District and a Small Part of Saipar Dolok Hole and Batang Angkola Districts. Meanwhile, the East Angkola sub-district can be planted with rice with the help of irrigation, especially in the dry season.

Reverse Total Shoulder Arthroplasty with a Superior Augmented Glenoid Component for Favard Type-E1, E2, and E3 Glenoids.

Uncorrected superior glenoid wear in patients managed with reverse total shoulder arthroplasty (rTSA) can result in increased complications, including baseplate failure. The present study quantifies the clinical and radiographic outcomes of patients with Favard type-E1, E2, and E3 glenoid deformity who were managed with rTSA with use of a superior or superior/posterior augmented glenoid baseplate. We retrospectively reviewed the records for 68 patients with shoulder arthritis and Favard type-E1, E2, or E3 glenoid deformity who were managed with primary rTSA and a 10° superior augmented or 10° superior/8° posterior augmented baseplate. The mean duration of follow-up was 40 months (range, 24 to 85 months). Outcomes were assessed preoperatively and at the latest follow-up with shoulder range of motion and use of outcome scores including the Simple Shoulder Test (SST), University of California Los Angeles (UCLA) score, American Shoulder and Elbow Surgeons (ASES) score, Constant score, and Shoulder Pain and Disability Index (SPADI) score. Radiographs were evaluated preoperatively and at the time of the latest follow-up. Differences in preoperative and postoperative range of motion and outcome metrics were assessed with use of a 2-tailed Student t test. The majority of patients experienced clinically meaningful improvements in terms of pain and function following rTSA with a superior or superior/posterior augment, with 94% of patients rating themselves as "much better" (73.5%) or "better" (20.5%) at the time of the latest follow-up. At least 88% of the patients exceeded the minimum clinically important difference (MCID) threshold, and 75% of patients exceeded the substantial clinical benefit (SCB) threshold, for each of the clinical outcome metrics and range of motion. Five complications were reported (prevalence, 7.4%), including acromial stress fracture (2 patients), posttraumatic scapular neck fracture (1 patient), chronic shoulder pain (1 patient), and aseptic glenoid loosening (1 patient). The present short-term clinical and radiographic study demonstrated that shoulder arthropathy with superior glenoid wear patterns (Favard types E1, E2, and E3) can be successfully treated with rTSA with a superior or superior/posterior augmented baseplate. Longer-term clinical and radiographic follow-up is necessary to confirm that these promising short-term results are durable. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Management of Major Postcholecystectomy Biliary Injuries: An Analysis of Surgical Results in 62 Patients.

Background:Management of injuries sustained during cholecystectomy requires expertise and involves a patient who is troubled, usually drained of personal resources. There has been an increase in incidence with laparoscopic cholecystectomy. The standard surgical management done for major biliary injuries is Roux-en-Y Hepaticojejunostomy (R-en-Y HJ).Materials and Methods:Patients managed surgically for definitive management of biliary injuries in the form of R-en-Y HJ were included. Data were collected from prospectively maintained records and through outpatient follow-up. Demographic data, early and late surgical complications, long-term outcomes, and follow-up results were analyzed.Results:Among the 62 patients, 26 were males, with a mean age of 37.4 ± 13.5 years. A total of 24 patients presented with ongoing biliary fistula. The Strasberg–Bismuth type of injury included types E1 in 8 (13%), E2 in 31 (50%), E3 in 19 (30.6%), and E4 in four patients (6.4%). There were no postoperative mortality and morbidity in 27.4% of patients. Atrophy–hypertrophy complex was seen in four patients, vascular injury in six patients, and an internal fistulisation with duodenum in two patients. Presence of comorbidities (P = 0.05), male gender (P = 0.03), tobacco use (P = 0.04), low albumin (P = 0.016), and more proximal (E4-E1) type of injury (P = 0.008) were independent predictors of postoperative morbidity (P < 0.05). The mean duration of patient follow-up was 26.2 ± 21.1 months.Conclusion:Optimization of preoperative nutrition, avoidance of intraoperative blood transfusion, proper timing of repair, and tension-free R-en-Y HJ draining all the ducts which is done at an experienced hepatobiliary center provide the best outcome.

The temperature sensitivity of ecosystem respiration to climate change in an alpine meadow on the Tibet plateau: A reciprocal translocation experiment

Information about the potential effects of climate change, especially cooling, on ecosystem respiration (Re) in alpine meadows is scarce. We determined the effects of warming and cooling on Re on the Tibetan Plateau using a 2-year reciprocal translocation experiment with 4 different vegetation types (3 alpine meadows and 1 alpine shrub differentiated by plant community composition) along an elevation gradient from 3200 to 3800m (with vegetation types E2, E4, E6 and E8 at 3200, 3600, 3800 and 3800m, respectively) during the growing seasons in 2008 and 2009. Mean growing seasonal Re decreased by 13.6, 30.3 and 40.7% per 200m rise in elevation (cooling) for vegetation types E2, E4 and E6, but increased by 1.3, 35.9 and 58.8% per 200m decrease in elevation (warming) for vegetation types E4, E6 and E8, respectively. Soil temperature explained 49.3–64.0% of daily Re variation and aboveground biomass explained 21.5–61.6% of average Re variation of the growing season for all vegetation types, but the effect of soil moisture on Re was small over 2-year. The values of Re temperature sensitivity increased with an increase in elevation for both warming (3.3, 24.3 and 53.5%°C−1 for vegetation types E4, E6 and E8) and cooling (8.0, 19.1 and 24.4%°C−1 for vegetation types E2, E4 and E6), suggesting that alpine meadow at higher elevation was more sensitive to both warming and cooling. Based on the values of Re temperature sensitivity for all pooled vegetation types (25.4, 5.6 and 19.6%°C−1 for warming, cooling and pooled warming and cooling), it could be over-estimated by 23% for warming alone compared with pooled warming and cooling. Therefore, asymmetrical responses of Re to warming and cooling should be taken into account when we evaluate the effect of temperature change on Re using models in the future.

Intracellular pH of symbiotic dinoflagellates

Intracellular pH (pHi) is likely to play a key role in maintaining the functional success of cnidarian–dinoflagellate symbiosis, yet until now the pHi of the symbiotic dinoflagellates (genus Symbiodinium) has never been quantified. Flow cytometry was used in conjunction with the ratiometric fluorescent dye BCECF to monitor changes in pHi over a daily light/dark cycle. The pHi of Symbiodinium type B1 freshly isolated from the model sea anemone Aiptasia pulchella was 7.25 ± 0.01 (mean ± SE) in the light and 7.10 ± 0.02 in the dark. A comparable effect of irradiance was seen across a variety of cultured Symbiodinium genotypes (types A1, B1, E1, E2, F1, and F5) which varied between pHi 7.21–7.39 in the light and 7.06–7.14 in the dark. Of note, there was a significant genotypic difference in pHi, irrespective of irradiance.

Manual faucets induce more biofilms than electronic faucets

Electronic faucets (types E1 and E2) and manual (M) faucets were studied for microbial quality, i.e., biomass and pathogenic microbes of biofilms in the faucet aerator, the water, and the outer surface of faucet in a hospital in Finland. Heterotrophic plate count content reflecting culturable microbial biomass and adenosine triphosphate content representing viable microbial biomass were smaller in the biofilms of E1-type electronic faucets than E2-type electronic faucets or M faucets. The likely explanation is the mixing point of cold and hot water (E1 and M: in the faucet; E2: in a separate box 50 cm before the actual faucet part). The highest amounts of Legionella (serogroups 2-15 of Legionella pneumophila) in a water sample (5000 cfu/L) and in biofilm samples (May-June 2008 sampling: 240 cfu/mL; November 2008: 1100 cfu/mL) were found in one E1-type faucet, which was lacking a back pressure valve due to faulty installation. This study reveals that certain types of electronic faucets seem to promote hospital hygiene, as they were associated with less microbial growth in biofilms in the faucet aerator, than some other types of electronic faucets or manual faucets, likely owing to the mixing point of cold and hot water. However, the faucet type had no direct effect on the presence of Legionella spp. Also correct installation is crucial.

Variations in Reactive Oxygen Release and Antioxidant Activity in Multiple Symbiodinium Types in Response to Elevated Temperature

As ocean temperatures rise, investigations into what the physiological effects will be on the symbiotic microalga Symbiodinium, and how these may play into the cnidarian bleaching response, have highlighted the contribution of reactive oxygen species (ROS). Previous studies have laid this groundwork using a limited number of Symbiodinium phylotypes, and so this study aims to expand this understanding by exploring the effects of sub-lethal elevated temperatures on the physiological response of seven genetically distinct types of Symbiodinium, including A1, B1, B2, C1, D, E1, and F2. The production of ROS (at 26°C, 29°C, 30°C, and 31°C) and activity of the antioxidants catalase (CAT) and superoxide dismutase (SOD) (at 26°C and 31°C) were measured as indicators of sensitivity or tolerance to heat stress. Symbiodinium types B1 and C1 were the most thermally sensitive, with C1 producing the highest amount of ROS at elevated temperatures. Types A1 and F2 were tolerant, having no increase in ROS production, and were the only types to increase both CAT and SOD activity with temperature stress. Type B2 had decreased ROS production and elevation of CAT activity, while type E1 had decreased levels of ROS production at elevated temperatures. Type D was the only Symbiodinium type to remain unaffected by elevated temperatures. These results are consistent with previous findings of relative sensitivity or tolerance to elevated temperatures, specifically with regards to types A1, B1, and F2. The inclusion of types B2, C1, D, and E1 provides further new evidence of how types differ in their thermal responses, suggesting differing mechanisms exist in the Symbiodnium response to higher temperature and highlighting the importance of establishing symbiont identity when exploring the response of intact associations to this type of stress.

Salmonella enterica serovar Typhi in Japan, 2001–2006: emergence of high-level fluoroquinolone-resistant strains

The phage types and antimicrobial susceptibilities of 226 isolates of Salmonella enterica serovar Typhi from imported cases in Japan between 2001 and 2006 were investigated. Most (93.8%) had travelled to Asian countries, particularly South East Asia. Twenty-one phage types were identified with E1 (30.5%), UVS (15.9%) and B1 (9.3%) being the most common. The frequency of multidrug-resistant strains reached 37.0% in 2006 with phage types E1 and E9 predominating. Almost half (48.2%) of the isolates were resistant to nalidixic acid and two isolates displayed high-level fluoroquinolone resistance. Three mutations, two in gyrA and one in parC, were identified in both isolates.

Laboratory experiment on drip emitter clogging with fresh water and treated sewage effluent

A laboratory experiment was carried out to study the emitter performance of three commonly used emitter types with the application of freshwater and treated sewage effluent (TSE). The three emitter types are the inline-labyrinth types of emitters with a turbulent flow (E1) and a laminar flow (E2) and the online pressure-compensation type of emitters (E3). The qualities of freshwater and TSE were measured, and the emitter performance was evaluated, using the relative emitter discharge, the reduction of emitter discharge ( q reduction), the coefficient of variation of emitter discharge (CV), the emission uniformity (EU), Christiansen uniformity coefficient (CU), and the percentage of emitter clogging ( P clog). Results showed that all indices were affected by water quality, emitter type and time of operation. The values of q reduction, CV and P clog for the TSE treatments were greater than those for the freshwater treatments. The values of EU and CU for the TSE treatment were lower than those for the freshwater treatments. The q reduction, CV and P clog increased and the EU and CU decreased as operational time increasing for the TSE treatment. For both freshwater and TSE treatments, the emitter clogging was more severe, the CV was greater, and the EU and CU were smaller for emitter type E2 than those for emitter types E1 and E3. Thus a more severe clogging was found for emitter type E2 due to its smaller flow-path dimension and higher manufacturing coefficient of variation in addition to the high pH values and relatively high total dissolved solids (TDS) values of the used water. Analyses of water quality and the precipitation components inside and at the outlet of emitters revealed that chemical precipitation was the main reason for emitter clogging due to high pH and ions’ concentration, especially in the TSE. Flushing emitters and drip pipes did not efficiently alleviate emitter clogging caused by chemical precipitation. In a conclusion, emitter type E3 showed a better anti-clogging function than emitter types E1 and E2 and was recommended for irrigation with TSE in the Beijing area of China.

Comparative Analysis of Salmonella typhi by rRNA Gene Restriction and Phage Typing

Phage typing and ribotyping were used to analyze 19 isolates of Salmonella typhi from sporadic cases and two outbreaks of typhoid fever in Malaysia in 1987 and 1990. The two outbreaks were associated with phage types D1 and E1 in Penang and Alor Setar respectively, and phage types D1, E1 and A (with 3 untypeable isolates) were present among the sporadic cases. Ribotyping detected 14 ribotypes among the 19 isolates thus establishing its higher discriminative capacity compared to phage typing. The outbreak isolates were more homogeneous by ribotyping and the data also suggested that one outbreak was propagated, multi-focal in nature (Penang) while another was a point- source traceable to a single event (Alor Setar).

Emerging resistance in Salmonella enterica serotype Typhi in Hong Kong

A total of 182 Salmonella enterica serotype Typhi isolated from three hospitals in Hong Kong from 1986 to 1992 were tested for their susceptibility to 21 antimicrobial agents. Four percent or less were resistant to chloramphenicol, ampicillin, some of the cephalosporins, nalidixic acid, tetracycline and trimethoprim and 6% to 1024 mg/l sulfamethoxazole. All were susceptible to the aminoglycosides and the 4-quinolones. Nineteen isolates were resistant to at least 1, and up to 9, antibiotics. Of 8 chloramphenicolor multiply-resistant isolates studied, only 3 could transfer their resistances while resistance of one could only be mobilized. Four of 5 ampicillin-resistant strains produced a β-lactamase of p I 5.5. Antibiotic resistances were mediated by plasmids of 106, 116 or 221 kb of incompatibility groups H, I1 and K. Three resistant isolates did not harbour any plasmid. A total of 43 (24%) S. Typhi harboured plasmids ranging in size from 4.3 to 221 kb. Plasmids of 106 kb and 8.5 kb were found in 17 and 10 isolates, respectively. Restriction enzyme digestion of these two plasmids showed that each could be differentiated into 3 types. Of 89 isolates that were phage typed, 38% were untypable, while 17% and 12% were of phage types E1 and A, respectively, and the rest belonged to 17 other types.

Insertion sequence IS200 can differentiate drug-resistant and drug-sensitive Salmonella typhi of Vi-phage types E1 and M1

The type strains of Vi-phage types E1, M1 and A of Salmonella typhi, together with drug-resistant and drug-sensitive strains of phage types E1 and M1 isolated in 1992 from patients associated with India or Pakistan, and a drug-resistant strain of phage type A isolated in South Africa in 1991, were characterised with respect to the presence of plasmids conferring resistance to antimicrobial drugs and their chromosomal insertion sequence IS200 profiles. The three type strains, the drug-sensitive strains of Vi-phage types E1 and M1, and a strain of phage type M1 resistant to ampicillin and trimethoprim but not to chloramphenicol, did not contain plasmids. In contrast, for strains of phage types E1 and M1 resistant to chloramphenicol, ampicillin and trimethoprim, and for the drug-resistant strain of phage type A, the complete spectrum of resistance was encoded by high molecular mass plasmids belonging to the H1 incompatibility group. Characterisation of IS200 profiles demonstrated that at least 13 IS200 copies were distributed on the chromosome of all strains tested. Although the IS200 profiles of the type strains of Vi-phage types A, E1 and M1 were identical, it was possible to distinguish between drug-sensitive and drug-resistant strains of Vi-phage types E1 and M1 isolated from patients infected in India and Pakistan by this method. It was concluded that although IS200 typing is not as discriminatory as phage typing for the primary subdivision of S. typhi, it may be useful for certain epidemiological investigations and, in particular, for investigating the origins of strains with multiple drug resistance.

Widespread occurrence of multiple drug-resistant Salmonella typhi in India.

Sixteen multiple drug resistant strains of Salmonella typhi belonging to Vi-phage types E1 (14) and O (2) and isolated in Southeast India in 1991 were characterized. All strains were resistant to chloramphenicol and the majority to trimethoprim and ampicillin. In all strains these resistances were encoded by plasmids of the H1 incompatibility group with molecular weights ranging from 110 to 120 megadaltons. Physicians in European countries should be aware that treatment may fail if patients with typhoid fever who have recently returned from the Indian sub-continent are given first-line treatment with chloramphenicol, trimethoprim or ampicillin. With the possible exception of young children, ciprofloxacin is currently the best choice for treatment of such patients.

Genetic reassortment of mammalian reoviruses in mice.

Reassortments between type 1 (Lang) and type 3 (Dearing) reoviruses were isolated from suckling mice infected perorally with an inoculum containing both type 1 and type 3 viruses. A total of five distinct reassortants (designated as E1 through E5) were isolated from animals during the course of the experiment. Two reassortants (E1 and E2) represented the majority of the reassortants isolated. The majority of genes of types E1 and E2 were derived from type 1 (Lang). However, E1 had an M2 gene and an S1 gene derived from type 3 (Dearing), while E2 had M2 and S2 genes derived from type 3 (Dearing). Thus, nonrandom reassortment between mammalian reoviruses can be demonstrated in vivo.

Colicins E4, E5, E6 and A and properties of btuB+ colicinogenic transconjugants.

E colicins are those inactive on btuB mutants, which lack the outer membrane protein that adsorbs vitamin B12, E colicins and phage BF23; types E1, E2, E3 and E7 have been defined by the specific immunity of E-colicinogenic strains to the type of E colicin they produce. Further immunity types - E4, E5, E6 - are now described. Shigella sonnei of colicin type 9 makes colicin E4, and Shigella sonnei of types 9A, 12 and 14 make colicin E6 (not colicin E3, as previously supposed). Many local Shigella sonnei isolates make E colicin of a new type - E5. The action of colicins E1 to E7 was (incompletely) blocked by vitamin B12, which also reduced the effect of A colicins (which are weakly active on Escherichia coli K12 btuB indicators). Escherichia coli K 12 given plasmid Co1A-23 by transformation was immune to A colicins but sensitive to colicins E1 to E7. A purported 'colicin E4' was shown to be of class colicin A. Escherichia coli K 12(CloDF13) transformants were immune to colicin E6. A 'cap' of colicin-sensitive indicator bacteria developed over, but not around, killed colonies of btuB+ E-colicinogenic strains, because of adsorption of colicin by non-induced bacteria of the colony. Killed colonies of btuB+ E-colicinogenic strains gave partly discrete lobes of colicin action on indicator lawns, instead of circular zones, apparently as a result of unstable variation in colicin production. The presence of a colicin E4, E5 or E6 plasmid in K12 btuB+ strains made them more sensitive to colicins E2 and E7, as shown by zones of partial translucency surrounding the ordinary colicin zones and by increased titre of colicin E2 and E7 preparations on such indicators.

Investigation of excitatory unit responses arising at different times after application of an electrical stimulus to the cerebral cortex.

1. Depending on the distribution of latencies of spike responses to single and repetititve (10 Hz) cortical stimulation at least three groups of excitatory responses can be distinguished from sensomotor neurons: initial (E1), secondary (E2), and postinhibitory (E3). 2. In intercellular recording, depolarization waves, differing in amplitude and duration, and which evidently lie at the basis of the spike responses appearing at different times after application of the stimulus, are detected from the same neuron. 3. Comparison of unit responses to cortical stimuli at different distances from the point of recording, and also of responses recorded in the intact cortex and in an isolated strip of cortex, suggests that type E1 responses are due mainly to the intracortical spread of excitation, whereas responses of types E2 and E3 are due to an excitatory inflow into the cortex from subcortical formations.

Structure of sensilla, olfactory perception, and behaviour of the bedbug, Cimex lectularius, in response to its alarm pheromone

When deprived of the terminal antennal segments, male and female bedbugs failed to respond to their alarm pheromone and to their assembling scent. Trans-oct-2-en-1-al or trans-hex-2-en-1-al, being the major constituents of the former, induce in adults and larvae of Cimex lectularius a typical alarm behaviour resulting in dispersal of assembled bedbugs; the rapidity of escape depends on the aldehyde concentration in the air. The behavioural threshold for adults is about 9×10 14 molecules of trans-oct-2-en-1-al or 6×10 15 molecules of trans-hex-2-en-1-al per ml air. The distal part of the terminal antennal segment of C. lectularius reveals the following sensilla: bristles (type A1), immersed cones (type B1), plates (type B2), grooved pegs (type C), smooth pegs (type D), hairs with even (type E1), and uneven wall thickness (type E2). The number and distribution of these sensilla is relatively constant and similar in both sexes, but differs slightly in neonate larvae. The pegs and hairs of types C, D, E1 and E2 were shown to have porous walls, a prerequisite for olfactory function. Receptor potentials were recorded from olfactory sensilla of types E1 and E2 after stimulation with trans-hex-2-en-1-al and trans-oct-2-en-1-al. The minimal concentration of trans-hex-2-en-1-al evoking a receptor potential is about 2×10 10 molecules per ml air. The above olfactory sensilla were found to respond also to hexan-1-al, but almost no responses to pentan-1-al, butan-1-al, trans-hex-2-ene, and trans-oct-2-ene were observed. A minimum chain length of six carbons atoms and a terminal carbonyl group are molecular prerequisites for optimal odorant activity, while the presence of a Δ 2-double bond is not essential for stimulation of the alarm pheromone receptors of the bedbug.

Mode of action of colicins of types E1, E2, E3, and K.

The effect of colicins on deoxyribonucleic acid and protein synthesis, and also their effect on the ability of T4 phage to replicate in Escherichia coli K-12, were studied. Colicins of type K inhibited deoxyribonucleic acid synthesis, protein synthesis, and phage growth. Among colicins of type E, there was an absolute correlation between mode of action and subdivision into types E(1), E(2), and E(3).