Innervation and control of tension in abdominal muscles of Blaberus discoidalis and Gromphadorhina portentosa

In Blaberus discoidalis and Gromphadorhina portentosa, the distribution of motor axons to the muscles which control movements of the spiracular valves at both respiratory and non-respiratory spiracles is identical. Both fast and slowly contracting heads of the opener muscles are innervated by an excitatory motor axon. Physiological properties of the opener excitor axon correlate with valve function. The slowly contracting head of the opener muscle is, in addition, innervated by a common inhibitor which also occasionally innervates closer muscle fibers. Activation of the common inhibitor terminates contraction of slowly contracting opener muscle fibres and initiates a rapid relaxation of these fibres.     

Neural control of homologous behaviour patterns in two blaberid cockroaches

Activity patterns of motoneurones which innervate spiracular muscles in two blaberid cockroaches, Blaberus discoidalis and Gromphadorhina portentosa, have been monitored during two homologous behaviour patterns: respiratory and non-respiratory tracheal ventilation. Based upon the activity of spiracular motoneurones during these two activities, the abdominal spiracles have been divided into three functional groups: vestigial, respiratory and non-respiratory. In Blaberus discoidalis spiracle 3 is vestigial, spiracles 6, 7, 8 and 10 are respiratory, and spiracles 4, 5 and 9 are non-respiratory. In Gromphadorhina portentosa spiracles 3 and 10 are vestigial, spiracle 4 is non-respiratory and spiracles 5–9 are respiratory.Respiratory spiracles in both species are characterized by activity patterns of their motoneurones during respiratory tracheal ventilation: low frequency firing at irregular intervals during the respiratory pause and a higher frequency burst synchronous with the expiratory abdominal compression. Non-respiratory spiracles are characterized by complete inactivity of their opener motoneurones during respiratory tracheal ventilation. These motoneurones are activated by mechanical stimulation in both species, which simultaneously suppresses activity in respiratory opener motoneurones. In Blaberus discoidalis, there are no differences between activity patterns of respiratory and non-respiratory closer motoneurones. In Gromphadorhina portentosa, not only do respiratory and non-respiratory closer motoneurones have different activity patterns, but the activity pattern of respiratory closer motoneurones is different during respiratory and non-respiratory tracheal ventilation. The functional implications of these several spiracular motoneurone activity patterns are discussed.     

Evaluation of rapid techniques for the detection of mycobacteria in sputum with scanty bacilli or clinically evident, smear negative cases of pulmonary and extra-pulmonary tuberculosis

The objective of the current study was to compare two rapid methods, the BBL Mycobacteria Growth Indicator Tube (MGIT TM) and Biotec FASTPlaque TB TM (FPTB) assays, with the conventional L?wenstein-Jensen (LJ) media assay to diagnose mycobacterial infections from paucibacillary clinical specimens. For evaluation of the clinical utility of the BBL MGIT TM and FPTB assays, respiratory tract specimens (n = 208), with scanty bacilli or clinically evident, smear negative cases and non-respiratory tract specimens (n = 119) were analyzed and the performance of each assay was compared with LJ media. MGIT and FPTB demonstrated a greater sensitivity (95.92% and 87.68%), specificity (94.59% and 98.78%), positive predictive value (94.91% and 99.16%) and negative predictive value (96.56% and 90.92%), respectively, compared to LJ culture for both respiratory tract and non-respiratory tract specimens. However, the FPTB assay was unable to detect nontuberculous mycobacteria and few Mycobacterium tuberculosis complex cases from paucibacillary clinical specimens. It is likely that the analytical sensitivity of FPTB is moderately low and may not be useful for the direct detection of tuberculosis in paucibacillary specimens. The current study concluded that MGIT was a dependable, highly efficient system for recovery of M. tuberculosis complexes and nontuberculous mycobacteria from both respiratory and non-respiratory tract specimens in combination with LJ media.     

Production efficiency of the bacterial non-ribosomal peptide indigoidine relies on the respiratory metabolic state in <Emphasis Type="Italic">S. cerevisiae</Emphasis>

Background

Beyond pathway engineering, the metabolic state of the production host is critical in maintaining the efficiency of cellular production. The biotechnologically important yeast Saccharomyces cerevisiae adjusts its energy metabolism based on the availability of oxygen and carbon sources. This transition between respiratory and non-respiratory metabolic state is accompanied by substantial modifications of central carbon metabolism, which impact the efficiency of metabolic pathways and the corresponding final product titers. Non-ribosomal peptide synthetases (NRPS) are an important class of biocatalysts that provide access to a wide array of secondary metabolites. Indigoidine, a blue pigment, is a representative NRP that is valuable by itself as a renewably produced pigment.

Results

Saccharomyces cerevisiae was engineered to express a bacterial NRPS that converts glutamine to indigoidine. We characterize carbon source use and production dynamics, and demonstrate that indigoidine is solely produced during respiratory cell growth. Production of indigoidine is abolished during non-respiratory growth even under aerobic conditions. By promoting respiratory conditions via controlled feeding, we scaled the production to a 2 L bioreactor scale, reaching a maximum titer of 980 mg/L.

Conclusions

This study represents the first use of the Streptomyces lavendulae NRPS (BpsA) in a fungal host and its scale-up. The final product indigoidine is linked to the activity of the TCA cycle and serves as a reporter for the respiratory state of S. cerevisiae. Our approach can be broadly applied to investigate diversion of flux from central carbon metabolism for NRPS and other heterologous pathway engineering, or to follow a population switch between respiratory and non-respiratory modes.

     

Behavioural and cardiovascular responses to electrical stimulation of the medulla oblongata of the cat

Effects of stimulation of the nucleus tractus solitarii, the dorsal motor nucleus of the vagus, the nucleus reticularis paramedianus, and the nucleus cuneatus were studied in free-moving cats. Stimulation of the medullary nuclei that are known to be involved in the central nervous control of cardiovascular functions might activate preprogrammed motor responses such as licking and sniffing, and induce complex behavioural response patterns such as sleep or flight reaction. Moreover, both lever-pressing for rewarding brain stimulation, and eating in food deprived cats might be modulated by these stimulations. In a shuttle box the cats showed no tendency toward shuttling during stimulation, except the stimulation of the nucleus reticularis paramedianus which produced aversion. The cardiovascular and respiratory effects varied parallel with the behavioural responses. It is concluded that the medullary nuclei related to visceral functions are capable of affecting somatomotor behaviour either directly on the motor system, or by inducing complex response patterns in which somatomotor and visceral responses are integrated.     

Mesenchymal control of branching pattern in the fetal mouse lung

The effect of mesenchyme on specialization of respiratory epithelium in the fetal mouse was tested in organ cultures. Heterologous combinations were made between respiratory and non-respiratory lung epithelia and the corresponding mesenchymes. Isolated terminal respiratory buds of fetal mouse lungs were recombined with mesenchyme from chick lung parabronchi, mouse trachea or from the avascular, non-respiratory air sacs of chick lungs. Isolated non-branching chick air sacs were combined with mouse terminal bud mesenchyme or mesenchyme from the respiratory branches of chick lungs. Air sac epithelia branched in a pattern characteristic of the chick lung when combined with chick respiratory mesenchyme and in a pattern characteristic of mouse lung when combined with mouse terminal bud mesenchyme. Mouse terminal bud epithelia did not branch with either mouse tracheal mesenchyme or chick air sac mesenchyme but branched in a chick pattern with chick parabronchial mesenchyme. Electron microscopic examination of the cultures showed that all chick air sac epithelial cultures failed to produce surfactant (lamellar bodies) even when they branched. Control cultures of mouse terminal buds contained large numbers of lamellar bodies; mesenchyme which suppressed branching reduced the number of lamellar bodies to only a few in a small proportion of the cells. Culture medium supplemented with growth factors and hormones increased the number of lamellar bodies in heterologous mouse combinations but did not bring the number to control levels. Supplemented medium had no effect on lamellar body production by chick air sac epithelium. The results indicate that branching pattern is determined by the mesenchyme surrounding the epithelial primordium. However, the capacity to synthesize surfactant is determined by the source of the epithelium; mesenchyme may control the degree of expression but not the absolute presence or absence of the differentiated condition.     

The contribution of sensory inputs to the pattern generation of breathing

Current concepts of the basic neural control system and its modulation by afferent inputs are reviewed. It is emphasized that, in analogy with locomotion, the central pattern generator (CPG) for automatic metabolic respiration does not depend on any afferent feedback from receptors sensitive to the movements of the "pump," or the streams of pumped air, for its production of a rhythmic motor output provides the CPG receives some "drive" inputs above threshold and adequate bias. The operation for a variety of reflexes and feedback loops is of fundamental importance, however, for adapting the breathing pattern to the varying requirements for gas exchange to the many behavioural, nonmetabolic demands on the breathing apparatus which are competing with its primary metabolic control functions. The presentation is focussed also on available evidence that the respiratory CPG exerts powerful modulations on the transmission in these reflex pathways controlling the pattern of breathing and adjusting it to the various metabolic and behavioural demands. Mechanisms for "gating," "phasic gain changes," and "phase-dependent reflex reversal" are exemplified.     

Spatio-temporal characterization of intercostal activity during breathing in the cat

It is envisaged that the motor control of the intercostal musculature--an assembly of mobile structures--can be characterized in terms of a conceptual spatially continuous control function, that underlies the discretely distributed muscular activity and reflects an inferred global dynamic control of the thoracic cage during breathing. The global control function is estimated by the spatio-temporal pattern obtained by averaging in time and space and interpolation of multichannel simultaneous intercostal EMG recording in the anaesthetized cat. Different examples of the experimental preparation in the presence of stimuli of different kinds are analysed. The resultant signal patterns are found to be self-consistent and capable of exhibiting systematically differing features in systematically differing experimental conditions, thus supporting the validity of the analysis and the choice of the estimator. It is concluded that a more detailed analysis of the requirements of this approach is then warranted. Such requirements are discussed, and, specifically, results that bear on the adequacy of spatial sampling rate are presented. It is suggested that such methods offer a promising approach in the study of motor control strategies of the respiratory apparatus.     

微电泳给予单胺类受体阻断剂对兔孤束区呼吸性单位的吗啡诱发抑制效应的影响

实验在46只局部麻醉、肌肉麻痹和切断双侧颈迷走神经的家兔上进行。记录延髓孤束区的单位放电活动。观察微电泳单胺类受体阻断剂对呼吸性单位的吗啡诱发抑制效应的影响。全身应用吗啡前,在86个吸气性单位中,妥拉苏林引起阻遏的只有9个,在92个吸气性单位中,赛庚啶引起兴奋的只有1个。而在全身应用吗啡诱发单位活动抑制的背景上,在59个吸气性单位中,妥拉苏林引起阻遏的有42个,在74个吸气性单位中,赛庚啶引起兴奋的有12个。但两者对非呼吸性单位的影响,吗啡应用前后均无明显差别。这些结果进一步支持下述假设,即在吗啡所致的呼吸抑制效应中,5-HT 可能起着抑制性递质的作用,而 NE 起着兴奋性递质的作用。     

呼吸道与非呼吸道标本主要非发酵菌分离株的耐药性比较

目的对2 229份住院患者标本进行分离培养,并对非发酵菌分离株进行药敏试验,了解呼吸道与非呼吸道主要分离株的耐药率差异,以便指导临床合理使用抗菌药物。方法收集2008年8月至2010年10月分离自患者呼吸道、非呼吸道标本的革兰阴性非发酵菌,采用VITEK-32全自动微生物鉴定药敏仪进行细菌鉴定,药敏测定采用K-B法,并比较呼吸道与非呼吸道标本所检出的主要革兰阴性非发酵菌对抗菌药物的耐药率差异。结果共检出非发酵菌556株,其中呼吸道标本366株,非呼吸道标本190株,前3位非发酵菌分离株分别为铜绿假单胞菌、鲍曼不动杆菌和嗜麦芽窄食单胞菌。非发酵菌菌株ESBLs、AmpC、MBL、同产ESBLs+AmpC和同产ESBLs+MBL检出率分别为17.62%、13.67%、14.39、12.23%和6.12%,其中呼吸道标本分离株铜绿假单胞菌的ESBLs、AmpC检出率明显高于非呼吸道标本(均P<0.05),鲍曼不动杆菌的ESBLs、AmpC检出率明显低于非呼吸道标本(均P<0.05);呼吸道、非呼吸道标本的铜绿假单胞菌、鲍曼不动杆菌和嗜麦芽窄食单胞菌分离株对多种抗生素的耐药率不同,差异均有统计学意义(均P<0.05)。结论呼吸道与非呼吸道标本分离的主要非发酵菌分离株对同一抗菌药物耐药率不同,治疗不同部位非发酵菌引起的感染,要考虑由于感染部位不同而产生的耐药性以及药物有效浓度的差异,根据药敏结果合理使用抗菌药物。     

Scanning Electronmicroscopic Observations on Development and Structure of Pericarp of Nelumbo nucifera Gaertn

Pericarp of Hindu lotus is developed from the ovary wall only. It is differentiated intothe exocarp, mesocarp and endocarp which can be clearly recognized. The vascular bundles,secretory apparatus and aerenchyma are present in the ground tissue. The aeration system is.associated with stomata (St), air passages (Ap)and chamber (Ch). St apparatus with a specific form are located deeply under epidermal cells. Ap is schizogenous. Chisschizolysigenous. The wall of Ch has perforations which lead to surrounding cells. Ap and Ch arein contact with St in both outer and inner epidermis (Ep), so the aeration system covers the wholepericarp. In Ep, there are several kinds of secretory apparatus with different slimes. Lacticifers are articulated, some of them are branched and some not. In xylem, annular and helicaltracheids and vessels, in phloem, sieve tubes, companion cells and their contents can be observed. On the opposite side of the funicular attachment near stigma develops a hump. Thepericarp hump (Ph) is a specific structure in lotus. After studies on its fine structure, developing process and the relation between fruit development and Ph, the author considered thatPb functions probably as a respiratory apparatus of the developing seed.     

Stimulation of the respiratory and phosphorylating activities in rat brain mitochondria by idebenone (CV-2619), a new agent improving cerebral metabolism

The effects of 6-(10-hydroxydecyl)-2,3-dimethoxy-5-methyl-1,4-benzoquinone (CV-2619) on the respiration and non-respiratory oxygen consumption induced by ascorbate and Fe2+ in rat brain mitochondria were studied. When CV-2619 (100 and 300 mg/kg) was orally administered to rats for 3 days, it increased the state 3 respiration stimulated by ADP, slightly decreased the state 4 respiration after the consumption of ADP and resulted in a significant increase of the respiratory control index (RCI) by 14-19% for glutamate oxidation (p less than 0.01) and 10-17% for succinate oxidation (p less than 0.05), respectively. The RCI increasing effect of CV-2619 was dose dependent, but the compound had no effect on the ADP/O ratio. CV-2619 significantly suppressed by about 10% the non-respiratory oxygen consumption (p less than 0.02), which closely associated with non-enzymatic reactions such as lipid peroxidation, membrane lysis and swelling of mitochondria. Thus, CV-2619 may contribute to stimulate the net ATP formation by the well-coupling of electron and energy transfer, and by the reduction of non-respiratory oxygen consumption in cerebral metabolism.     

National survey of tuberculosis notifications in England and Wales 1978--9. Report from the Medical Research Council Tuberculosis and Chest Diseases Unit.

A survey of all tuberculosis notifications in England and Wales for a six-month period showed that 70% of 3732 newly notified, previously untreated patients had respiratory disease only, 23% had non-respiratory disease only, and 7% had both. Fifty-seven per cent of patients were of white and 35% were of Indian subcontinent (Indian, Pakistani, or Bangladeshi) ethnic origin, the latter group contributing over half the cases of non-respiratory disease. The estimated overall annual notification rate per 100 000 population for 1978--9 was 16.4 for England and 13.5 for Wales. The rates differed considerably between the different ethnic groups in England, the highest rates occurring in the Indian and in the Pakistani and Bangladeshi groups and the lowest in the white group; the differences in the non-respiratory rates were the more striking. Nearly a quarter of patients with respiratory disease had large pulmonary lesions, the proportion being higher for the white group than for the Indian subcontinent group. Over half the patients had positive cultures for tubercle bacilli and over a third had positive smears; both proportions were higher for the white group. This survey has identified many of the problems which tuberculosis presents in England and Wales today. These include the substantial number of patients with sputum-positive disease, the considerable variation in the rates in the different ethnic groups, and the not uncommon occurrence of childhood tuberculosis.     

The coupled evolution of breathing and locomotion as a game of leapfrog

Because the increase in metabolic rate related to locomotor activity places demands on the cardiorespiratory apparatus, it is not surprising that the evolution of breathing and of locomotion are coupled. As the respiratory faculty becomes more refined, increasingly aerobic life strategies can be explored, and this activity is in turn expedited by a higher-performance respiratory apparatus. This apparent leapfrogging of respiratory and locomotor faculties begins in noncraniate chordates and continues in water-breathing and air-breathing vertebrates. Because both locomotor and cardiorespiratory activities are coordinated in the brain, neurological as well as biochemical coupling is evident. In spite of very different breathing mechanisms in various vertebrate groups, the basic respiratory control mechanisms appear to have been conserved, and respiratory-locomotor coupling is evident in all classes of vertebrates. Hypaxial body wall muscles that were strictly locomotor in fish have respiratory function in amniotes, but some locomotor function remains in all groups.     

Effects of levodopa therapy in Parkinson's disease II. Measurement of behavioural changes

Forty-seven patients with Parkinson''s disease were evaluated prior to and during levodopa treatment (at five weeks and at six months), to obtain quantitative measures of the effects of the disease and of levodopa on a variety of cognitive and psychomotor functions, by means of psychological tests and special apparatus. Analysis of the findings in relation to a comparable control group shows that before treatment patients had impaired performance of all motor tasks, but no differences in cognitive functioning were found. Most motor functions had improved after five weeks on levodopa and this improvement was maintained at the six-month follow-up, but cognitive functions remained largely unchanged. The relationship between patients'' age, disability, duration of illness and drug tolerance is also discussed in relation to the functions measured.     

Comparative analysis of the effects of physical exercise

The purpose of this study was to assess anthropometrical, somatomotor, and cardio respiratory characteristics of athletes and non-athletes subjects to establish which effects of the organized physical training discriminate well between them. Subjects were 61 athlete and non-athlete medical students. Four groups were formed relying upon gender and physical activity. Body measures were computed. The motor abilities were tested by a set of static and dynamic motor tests, and cardio respiratory functions were recorded. No statistically significant differences were obtained from the comparisons of the body measures of basketball players and non-athlete medical students, except the body height. In contrast, significant differences were found both between the motor performances and between the cardio respiratory functions of the athlete and non-athlete groups. The body mass index (BMI) and the body fat (%) correlated negatively with static hanging, vertical jumping, and balance capability. On the contrary, BMI and body fat correlated positively with systolic blood pressure and vital capacity. The present results show that the effects of regular physical exercise on motor performances and cardio respiratory functions differentiate better between the athlete and non-athlete subjects than the changes in body measures.     

Assembly and stability of flagellar motor in Escherichia coli

Bacterial flagellar motor is a highly ordered and complex supramolecular structure that powers rotation of flagella and serves as a type III export apparatus for flagellar assembly. Motor biogenesis represents a formidable example of self-assembly, but little is known about early steps of the motor structure formation. Here we used a combination of fluorescence microscopy techniques to dissect the order of the motor assembly in Escherichia coli cells, to map in vivo the underlying protein interactions and to investigate dynamics of protein exchange in the assembled motor structure. Our data suggest that motor self-assembly is initiated by oligomerization of the membrane export apparatus protein FlhA, which is followed by the recruitment of the MS ring component FliF and by the ordered association of other motor proteins. The assembly process combines the hierarchy with cooperativity, whereby the association of each subsequent motor structure stabilizes the growing assembly. Our results provide a novel and so far the most complete view of the early steps in flagellar motor assembly and improve understanding of the motor structure and regulation.     

继发性肺结核伴呼吸衰竭患者肺功能与血气指标的相关性

摘要 目的：探讨继发性肺结核伴呼吸衰竭患者肺功能与血气指标的相关性。方法：2018年3月到2020年1月选择在本院诊治的继发性肺结核患者122例,所有患者都给予肺功能与血气指标检测,并进行相关性分析。结果：122例患者根据合并呼吸衰竭情况分为呼吸衰竭组(n=48)与非呼吸衰竭组(n=74)。呼吸衰竭组的用力肺活量(Forced vital capacity,FVC)、第一秒用力肺活量(forced expiratory volume in one second,FEV₁)、FEV₁/FVC、MMEF、MEF50、MEF25值都显著低于非呼吸衰竭组(P<0.05);呼吸衰竭组的PaO₂与Hb值显著低于非呼吸衰竭组(P<0.05),两组PaCO₂、pH值对比差异无统计学意义(P>0.05);呼吸衰竭组的低氧血症、高血红蛋白血症等发生率显著高于非呼吸衰竭组(P<0.05),两组高碳酸血症发生率对比差异无统计学意义(P>0.05)。在呼吸衰竭组中,Spearman 相关性检验分析显示FVC、FEV₁、FEV₁/FVC、MMEF、MEF50、MEF25与PaO₂、Hb存在相关性(P<0.05)。结论：继发性肺结核伴呼吸衰竭患者在临床上比较常见,多伴随有肺功能下降与血气指标异常,呼吸衰竭患者的肺功能与血气指标存在相关性。