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Freshwater scarcity and soil salinity are amongst the main obstacles for sustainable development of irrigated agriculture, particularly in arid regions. A 2-year field investigation was conducted at an experimental field in south-east Iran during the 2017 and 2018 growing seasons to evaluate the individual and integrated effects of water-saving irrigation strategies and organic soil amendment (OSA) applications on yield and water productivity of ajwain (Trachyspermum ammi), which is known as an important medicinal plant in Iran. A split-plot design with 16 treatments was used in the field trial. Treatments were created by combining four irrigation strategies, including full irrigation with freshwater [FF], partial root-zone drying (PRD) with freshwater (PF), PRD with saline water (PS), and PRD with alternating application of fresh and saline water (PFS), were combined with four types of soil amendments, including no amendment (control), charcoal nano-biochar (NB), composted cow manure (CM), cow manure vermicompost (VM). Results showed that in the absence of OSA application, exposing crops to salinity/water stresses caused 3.7–17.6% and 4.5–17.7% reduction in the crop’s seed yield and above-ground biomass, respectively, while enhancing the crop’s oil concentration and oil yield by 9.1–30% and 1.4–18.3%, respectively. Along with a 34–63% freshwater saving, a 24.9–91.2% increase occurred in the crop’s water productivities compared to the FF treatments. Integrating OSA application with freshwater-saving irrigation caused up to 58, 27.1, 60, 138, and 285% increase in the crop’s seed yield, biomass, oil concentration, oil yield, and water productivity, respectively, compared to the FF-control treatment. However, VM performed best, and CM took second place. Based on the results, it can be concluded that such integrations provide opportunities for developing Ajwain’s production in arid regions with limited access to freshwater resources.

Objective: The purpose of the present preliminary study was to explore the prevalence of nonmedical abuse of benzodiazepines in a group of opiate-dependent patients who were on methadone maintenance treatment (MMT) program in outpatient clinics in the south-west of Tehran, Iran. Methods: 114 male and female opiate-dependent clients who met DSM.IV-TR criteria for opiate dependence with mean age 36.5 years participated in the study from 16 clinics and completed a self-report questionnaire on demographics and substance use details. Then the participants were interviewed on the details of nonmedical abuse of benzodiazepines. Results: The study findings indicated that the current nonmedical abuse of benzodiazepines was commonly prevalent among participants. The most common current benzodiazepines abused were alprazolam (100%) followed by chlordiazepoxide (96.5%), clonazepam (94.7%), diazepam (86.8%), lorazepam (79.8%) and oxazepam (73.7%) respectively. Depression (77%) and anxiety (72.8%) were frequently reported as the most important reasons associated with consuming benzodiazepines followed by problem in anger control (44.7%), suicide thought (12.3%), self-injury (7.9%), and suicide commitment (5.3%) respectively. Conclusion: Nonmedical abuse of benzodiazepines is an important problem among opiate addicts which should be considered in treatment interventions during MMT program.

The effect of enflurane on the firing activity (spikes/sec) of the inspiratory neurons of the dorsal respiratory group (DRG) of the medulla oblongata was studied in decerebrate, paralyzed, mechanically ventilated cats before and after bilateral cervical vagotomy. Inspiratory neuronal activity, phrenic neurogram, arterial blood pressure, tracheal pressure, and end tidal CO2 concentration were recorded. Cells whose firing activity was in phase with that of the phrenic nerve were considered inspiratory neurons. Administration of 1 and 2% enflurane in oxygen produced gradual, significant, and dose-dependent depression of the cell activity with cervical vagi either intact or severed. Recovery of the cell activity occurred after termination of enflurane administration. In cats with intact vagi, 10 min after introduction of 1 and 2% enflurane, the cell activity (mean +/- SE) expressed as percentage of the control was 70 +/- 6% (P less than 0.05) and 48 +/- 5% (P less than 0.01), respectively. Bilateral cervical vagotomy did not affect the degree of cell depression due to enflurane. Hypercarbia induced by inhalation of 5% CO2 increased cell activity, but it did not block enflurane-induced cell depression, although it reduced it. It may be concluded that enflurane depresses the activity of the inspiratory neurons of the DRG. The results also suggest that the respiratory depressant effect of enflurane has a central component and that the DRG region may serve as a site to mediate the enflurane-induced respiratory depression.

The perioperative changes in the serum concentration of creatine phosphokinase (CPK) and its isoenzymes MM, MB, and BB and of lactic dehydrogenase (LDH) and its isoenzymes LDH1 to LDH5 were determined during craniotomy in order to distinguish operation-induced changes in these enzymes from those due to acute myocardial infarction and malignant hyperthermia. Twenty-eight male patients, 29 to 76 years of age (mean +/- SD = 58 +/- 13.2 years), undergoing craniotomy for tumor reseaction (n = 26) or cerebral artery aneurysm clipping (n = 2) were included in this study. Ten serial blood samples were obtained from each patient: one sample before and another after induction of anesthesia, and eight samples after the incision, over a period of 70 h. The preinduction serum CPK level of 97 +/- 32 U/L (mean +/- SD) increased gradually and significantly and reached the peak level of 542 +/- 116 U/L 34 h after incision (p

The mechanism of action of local anesthetics on synaptic transmission and their effects on synaptic components and on electrophysiologic properties of the nerve cell body are not clear. Therefore, the effects of lidocaine and bupivacaine on pre- and postsynaptic mechanisms underlying synaptic transmission in sympathetic ganglia were studied utilizing the techniques of intracellular recording and stimulation on isolated superfused superior cervical ganglia of rats. Lidocaine and bupivacaine either depressed or completely blocked synaptic transmission in sympathetic ganglia in a dose-dependent manner. Blockade of axonal conduction in presynaptic fibers was preceded by increased latency (the latency increased from 11.2 +/- 0.9 to 16.5 +/- 1.4 ms, mean +/- SEM, P less than 0.01) when the drugs were applied to the presynaptic nerves. Application of the drugs directly to the ganglion produced alterations in postsynaptic membrane properties consisting of decreased membrane resistance (from 40 +/- 3 to 32 +/- 3 M omega, P less than 0.01), increased firing threshold (from 14 +/- 0.5 to 18 +/- 0.5 mV, P less than 0.01), and decreased action potential amplitude (P less than 0.01) and/or blockade of action potential generation. Resting postsynaptic membrane potential did not change significantly. These changes were reversible. However, even after the excitatory postsynaptic potential resulting from presynaptic nerve stimulation had fully recovered during washout of the local anesthetic, the threshold for evoking the spike potential (firing level) still remained elevated for both presynaptic and intracellular stimulation of the ganglion cell, suggesting prolonged cell depression.(ABSTRACT TRUNCATED AT 250 WORDS)

While the effects of local anaesthetics on axonal conduction and axonal membrane have been extensively studied, there is little information about the actions of these agents on nerve cell soma. Therefore, the effects of the amide local anaesthetic bupivacaine on the electrophysiologic properties of the nerve cell soma were studied on isolated superfused superior cervical ganglia of rats. Administration of 100-200 nM of bupivacaine to the preparation produced marked changes in membrane properties of the cell soma. The resting membrane potential did not change, but the membrane resistance decreased 20% (P less than 0.01). The firing threshold, the action potential duration at 50% of maximal amplitude, and the intracellular current threshold for firing the cells increased significantly (P less than 0.01), while the action potential amplitude decreased significantly (P less than 0.01), before its complete blockade. The results show that the cell soma is a major site of action of local anaesthetics. The implication of the results is that when local anaesthetics are applied to areas where cell bodies and processes (axons and dendrites) are present together, such as during celiac plexus block, lumbar sympathetic block, stellate ganglion block, etc., they will all be effectively depressed and/or blocked.

The effects of intravenous administration of fentanyl (50 and 100 micrograms/kg) on the discharge activity of the medullary inspiratory neurons and of the phrenic nerve were studied following vagotomy in nine decerebrate, paralyzed mechanically ventilated cats. In six cats, the inspiratory neurons explored were in the dorsal respiratory group (DRG) associated with the nucleus of the tractus solitarius (NTS), while in the remaining three, they were in the ventral respiratory group (VRG). In the former group, the rhythmic discharge of the inspiratory neurons was disrupted by fentanyl and replaced by a continuous discharge superimposed with irregularly occurring bursts. These changes were also reflected by the phrenic nerve discharge. Inspiratory neuronal activity increased significantly (P less than 0.05) at 1 and 5 min after completion of fentanyl injection. Disruption of the rhythmic activity of the inspiratory neurons and its replacement by a continuous and irregular discharge may lead to sustained contraction of inspiratory muscles and cessation of respiration. In the VRG, the activity of the inspiratory neurons was totally abolished by fentanyl. Thus, it appears that different groups of medullary inspiratory neurons have differential sensitivity to fentanyl. Nalbuphine, an opiate agonist-antagonist, restored the normal pattern and magnitude of the activity of the inspiratory neurons.

Effects of intravenous injection of sheep hydatid cyst fluid on respiratory and cardiovascular systems were studied in sodium pentobarbital-anesthetized dogs. Under sterile conditions, the fluid was drawn from the liver and lung hydatid cysts of sheep, and centrifuged for 20 min at 500g. The supernatant fluid was used as the test solution. In a majority of animals, administration of 5 ml of the cyst fluid caused a sharp fall in arterial blood pressure, with or without respiratory changes. The latter, when present, included temporary cessation of respiration followed by rapid shallow breathing. There was usually an increase in the heart rate as the arterial blood pressure dropped. Atropine, 0.5 mg/kg body wt, given subcutaneously prior to the cyst fluid administration, did not block the responses. Cardiovascular responses produced by intravenous injection of cyst fluid were similar in dogs with positive pressure breathing and with spontaneous breathing. In 7 out of 10 responsive dogs, pretreatment with the antihistamine, chlorpheniramine, abolished the respiratory and cardiovascular responses.

The purpose of the present investigation was to determine the normal perioperative variations in the serum concentration of creatine phosphokinase (CPK) and its isoenzymes MM, MB, and BB, and of lactic dehydrogenase (LDH) and its isoenzymes LDH1 to LDH5 to distinguish operation-induced changes in these enzymes from those due to acute myocardial infarction or malignant hyperthermia. In 30 patients, 52 to 75 years of age undergoing elective orthopedic operations, 10 serial blood samples were obtained in the perioperative period: two samples before skin incision and eight samples after the incision over a time span of 70 hours. The preinduction mean serum CPK level of 141 U/L increased gradually and significantly and reached a maximum mean concentration of 809 U/L 34 hours after incision (p less than 0.01). The CPK-MM percent increased after incision, whereas that of CPK-MB and CPK-BB decreased, although their absolute values in terms of U/L rose. The preinduction mean serum LDH value of 173 U/L increased gradually after incision and achieved peak levels at 34 hours (203 U/L) and 58 hours (210 U/L) after incision (p less than 0.05). The LDH1:LDH2 ratio did not change. The LDH5 percent increased and peaked 10 hours after incision (p less than 0.05). There was a significant correlation between severity of operation-induced tissue damage and the serum CPK concentration (p less than 0.001). The large increase in total CPK (primarily MM fraction) occurring after surgery may minimize the percentile effects caused by an increase in MB level due to myocardial infarction.

The effects of intravenously administered fentanyl (25 micrograms/kg, n = 9; 50 micrograms/kg, n = 5) and alfentanil (12.5 micrograms/kg, n = 5; 25 micrograms/kg, n = 7) on the noxiously evoked, single-unit activity of cells in the nucleus reticularis gigantocellularis (NRGC) were studied in decerebrate cats. Only cells of the NRGC excited exclusively by supramaximal electrical stimulation of A delta fibers (noxious stimulation) of the superficial radial nerve were studied. The noxiously evoked activity of all cells in the NRGC was suppressed by the administration of opioids (by 58 and 88% for fentanyl, 25 micrograms/kg and 50 micrograms/kg, respectively; by 35 and 78% for alfentanil 12.5 micrograms/kg and 25 micrograms/kg, respectively). Fentanyl and alfentanil effects were antagonized by the intravenous administration of naloxone. These results indicate that opioid suppression of noxiously evoked activity is seen in neurons located in the brainstem, and thus suppression of brainstem neurons may be important in the production of fentanyl and alfentanil analgesia.

Intracellular recording and dye injection were used to study the morphological and electrophysiological properties of rat pelvic ganglion cells. The dye-injected cells measured on the average 37 μm by 22.5 μm and had a mean number of 1.5 primary processes (axon and dendrites). The cells received unmyelinated preganglionic inputs from either the pelvic (parasympathetic) or the hypogastric (sympathetic) nerves, but no cells received inputs from both nerves. The number of synaptic inputs to each cell varied between 1 and 5 with a mean of 2. Each cell had at least one large amplitude suprathreshold EPSP which always initiated an action potential. These properties, namely, morphological simplicity, small number of inputs, security of synaptic transmission and lack of convergence between sympathetic and parasympathetic inputs, suggest that the capacity for synaptic modulation and integration in this ganglion is minimal. Such a structure should therefore relay preganglionic information to target organs with little or no alteration.

Three groups of cats, a conscious, an anesthetized, and a decerebrate one, were subjected to heat stress while their respiratory rate and rectal temperature were continuously monitored.Panting developed in the conscious and anesthetized cats, but not in the decerebrate ones. The mean panting rectal temperature among the conscious cats was 38.9 and among the anesthetized cats 40.1 °C. The corresponding mean respiratory rates were 272.8 and 244.8/min respectively.The difference in the rectal temperature thresholds for panting and the difference between the corresponding respiratory rates for the above two groups were statistically significant (p