Respiratory damage caused by long-term inhalation of high concentration of sulphur-dioxide in dogs

It has been tried in this study to produce chronic obstructive bronchitis in dogs by exposing them to high concentrations of SO2. The study was extended to 175 days and during that period the animals were exposed to 300-500 ppm SO2 for a total of 435 h. None of the three dogs developed serious respiratory damage. Most of the symptoms were transitory. Histological examinations showed increased number of goblet cells in trachea, main- and lobar bronchi and a slight alteration of the bronchial glands.

[Airway resistance and lung volumes (author's transl)]

Whole-body plethysmography for measuring airway resistance and intrathoracic gas volume is a valuable tool for diagnosing pulmonary and airway functions. It is desirable to know momentary airway resistance in the course of a forced expiration and vital capacity in relation to predicted and actual thoracic gas volume as well as predicted and actual total capacity. This is a reliable means of discovering limitations of lung ventilation despite normal airway resistance during normal ventilation. With a computer and plotter attached to a whole-body plethysmograph such volume-airway resistance curves can be rapidly and well reproduced without stressing the test person. In addition, it also makes it possible to measure routinely the volume resistance breaking point (largely comparable to "closing capacity") even in ill patients.

Mechanism of increased tracheo-bronchial response to inhalative acetylcholine aerosol in pulmonary vascular congestion and unilateral pulmonary artery occlusion

The study was carried out in anesthetized, intubated and spontaneously breathing dogs. The aim of this study was to examine the responsiveness of the tracheo-bronchial system to inhalative ACh. It was considered that any change in ACh-sensitivity signifies the involvement of receptors in the lung itself. Increased pressure in the right heart and main pulmonary artery did not affect the ACh-sensitivity. Whereas, the sustained pulmonary vascular congestion produced by blocking the ascending aorta or by glass bead embolism provoked greater ACh-sensitivity. Increased ACh-sensitivity was also observed in unilateral pulmonary artery occlusion. ACh-sensitivity was greater in the later part of occlusion or vascular congestion and persisted even after the occlusion or block was withdrawn. It is concluded that the increased ACh-sensitivities in pulmonary vascular congestion and in unilateral pulmonary artery occlusion are due to the formation of edema and atelectasis respectively. Anyway, the disturbance of the metabolism of the receptor cells around the small vessels of the lung circulation seems to be essential.

Relationship between pulmonary embolism, airway obstruction and hypersensitivity of the airways in dogs: influence of partial vagus nerve blockade

Experiments in dogs showed an increase in deltaPoes/100 ml TV after embolization which returns to normal after blocking the vagus nerves, indicating an increase in airway resistance. A marked sensitization to ACh inhalation by embolism with both blood clots and glass beads was demonstrated. This hypersensitivity is vagus-dependent.

[Reaction of the cardio-respiratory-system following acetylcholine inhalation and the dependency from the body position on anaesthetised dogs (author's transl)]

The bronchomotoric reaction following ACH-aerosol in low concentrations is dependend on the position of the body on dogs. Up till one maximal reaction the increase of the airway resistance is always stronger in the lateral position. Nevertheless the breathing minute volume is constant. Concentration reaction curves will be shown. Arterial blood gases, heart rate, and pressure in the arteria femoralis were also measured. The different strongness of the reaction following ACH-inhalation will be caused by the predominantely unilateral ventilation of the animals in the lateral position.

Effect of unilateral vagus blockade on antigen-induced airway obstruction

Respiratory hypersensitivity and the effect of unilateral vagus blockade on the same, after the use of Ascaris extract aerosol, are studied in three boxer dogs with spontaneous reactivity to this aerosol. The dogs were exposed initially to Ascaris extract aerosol, and this exposure was repeated after unilateral vagus blockade and after its lavage. The principal parameters, deltaPoes (mm Hg)/100 ml TV, are given as a measurement of airway flow resistance and respiratory rates. The spontaneous respiratory distress observed in all the animals after exposure to the mentioned aerosol was avoided with unilateral blockade of the nervus vagus.

Differential diagnosis of ventilatory disorders with the help of volume/flow diagram

Volume/flow (V/v) diagrams obtained from 82 healthy and pulmonary diseased subjects were analyzed. A formula had been worked out on the basis of determined slow vital capacity, for the calculation of maximum forced expiratory flow (VEmax). The expiratory volume/flow curves were used for the computation of lung conpliance (C1). These calculated values of VEmax and C1 were highly correlated to the measured values. It is concluded that these calculated values would provide a good index for the preliminary differential diagnosis of the pulmonary disorders.

Antigen-induced airway obstruction and the influence of vagus blockade

Respiratory hypersensitivity to Ascaris antigens is carried out on 9 dogs. The participation of vagus reflex on this respiratory distress is studied in 4 of these dogs. The dogs were exposed initially to Ascaris aerosol, then to egg albumin and NaCl aerosol for control, and once more to Ascaris aerosol after bilateral vagi blockade and lavage, respectively. The principal parameters studied were deltaPoes (mm Hg)/100 ml TV as a measurement of flow resistance in the airways, and respiratory rates (Poes=changes of oesphagus pressure; TV=tidal volume). All the animals presented a significant respiratory distress with Ascaris aerosol, which could be clearly avoided with the central bilateral blockade of nervus vagus.

Effect of ascaris extract applied intravenously, on segment bronchus and the influence of ipsilateral vagus blockade

Respiratory hypersensitivity and systemic effects after local application of Ascaris suum extract on the segmental bronchus and after its intravenous infusion are studied on four boxer dogs. Influence of ipsilateral vagus blockade on the respiratory hyperreactivity after intrabronchial application of ascaris was also investigated on the same dogs. Ascaris extract was applied in liquid form directly through a catheter into the right segmental bronchus. Egg albumin was applied in the same way for control. Local application of ascaris was repeated after ipsilateral central vagus blockade and once more after recovering vagus effect by lavage. At the end of the experiments ascaris extract was infused intravenously. The parameters studied were: deltaP(oes) mm Hg/100 ml TV (as a measurement of flow resistance in the airways), respiratory rates, arterial blood gases and pH, heart frequency, systemic blood pressure and histamine concentration per milliliter of plasma. All the animals presented a remarkable respiratory distress with local ascaris application, which could be clearly avoided with ipsilateral central vagus blockade. This respiratory hyperreactivity was not observed after intravenous infusion of ascaris extract, but a significant systemic effect, which was not the case after local application, could be observed.

An outbreak of dysentery caused by Shigella dysenteriae type 1 on a coral island in the Bay of Bengal

An epidemic of severe dysentery occurred on St. Martin Island in the Bay of Bengal at a time when the island, with a population of 1,318, was isolated from the mainland because of the monsoon season. There were 434 cases and 28 deaths within a three-month period. Mortality (2%) was limited to the very young and the elderly. Shigella dysenteriae type 1 (Shiga bacillus) was isolated from 12 of 65 rectal swab specimens. All strains gave similar biochemical reactions and were resistant to tetracycline, chloramphenicol, streptomycin, and the sulfonamides but were sensitive to ampicillin, kanamycin, and gentamicin. No other organism was implicated in the outbreak. The disease disappeared from the island after institution of chlorination of the sources of drinking water and effective treatment of patients.

[Local oversensitivity of sensoric receptors as cause of reflectoric airway obstruction (author's transl)]

The effect of local intratracheal, intrabronchial, and intravenous application of histamine, has been studied in dogs. Control studies are also carried out with saline. There is an increase in intrathoracic pressure per 100 ml of tidal volume due to locally applied histamine. This change is considered as the measure of bronchoconstriction. There is also a significant change in the bronchial sensitivity to acetylcholine inhalation. The intravenous application of the same quantity of histamine produces very little change in the bronchial sensitivity though it has produced strong and prolonged circulatory effect and even transitory respiratory arrest. The application of saline produces no change. It is concluded that the local chemical stimulus can sensitize the whole respiratory system and produces greater bronchconstriction involving some reflex path.

Effects of shade and nitrogen levels on quality Bangladhonia production

A field experiment was conducted to determine the optimum shade level and nitrogen fertilizer for quality Bangladhonia (Eryngium foetidum L.) production at the Bangahandhu Sheikh Mujibar Rahman Agricultural University (BSMRAU) Research Farm during December 2002 to May 2003. The treatments consisted of four shade levels (0, 25, 50, and 75% shades) and five nitrogen rates (0, 115, 138, 161, and 184 kg N/ha). Shades were artificially created by using nylon nets of different mesh sizes and colours. Fifty percent shade and application of 161 kg N/ha independently as well as in combination gave the maximum fresh yield of Bangladhonia. β-carotene and vitamin C contents in Bangladhonia leaves were maximum in full sun light (0% shade) followed by 25 and 50% shade. Application of 161 kg N/ha produced the highest amount of β-carotene and vitamin C followed by 184 kg N/ha. The lowest amount of leaf fibre (1.30%) was recorded from 75% shade closely followed by 50% shade (1.76%), whereas the maximum amount of leaf protein was found at 50% shade. Application of 184 kg N/ha gave the highest amount of leaf protein and less leaf fibre that was followed by 161 kg N/ha. The results revealed that Bangladhonia performed better in terms of fresh yield and quality under 25-50% shade condition. Key Words: Bangladhonia; shade; nitrogen; yield; quality. DOI: 10.3329/bjar.v34i2.5791Bangladesh J. Agril. Res. 34(2): 205-213, June 2009

An Unusual Orbitocranial through and through Penetrating Injury by in Situ Teta: Can we do Better for this type of Unfortunate Patient?

Through and through orbitocranial penetrating injury by in situ teta is extremely rare. We managed such a case in Dhaka Medical college hospital with many limitations. In spite of all possible supports that were available in our set up, patient did not survive. Presentation, investigations, surgical and other supportive management will be highlighted in this case report. Key Words: Orbitocranial injury; penetrating injury; teta. DOI: 10.3329/jdmc.v18i2.6285 J Dhaka Med Coll. 2009; 18(2) : 185-187

Effects of planting material and earthing-up on yield and yield contributing attributes of Mukhi Kachu

An investigation was carried out at Agricultural Research Station, Pahartali, Chittagong during February to August 2002 to select suitable size of planting material and proper time of earthing-up to obtain higher yield of Mukhi Kachu. Three planting materials, primary corm (40g), half cut corm (20g), and secondary corm (10g) and four times of earthing-up, 1 month, 2 months, 3 months, and 4 months after planting were used. Different planting materials showed significant difference on weight of total corms/plot, weight of total cormels/plot and cormel yield. Different times of earthing-up showed significant effects on the parameters studied except no. of cormels/hill and weight of cormels/hill. The highest (3.71 t/ha) corm yield was obtained when primary corms were planted and earthing-up was done three months after planting. The combination of P1E ( primary corm x 3 months after planting) gave the highest (8.37 t/ha) cormel yield. Key Words: Mukhi Kachu; corm; cormel; planting material; earthing-up.  DOI: 10.3329/bjar.v34i2.5798Bangladesh J. Agril. Res. 34(2): 263-267, June 2009