Outcomes of biological therapy in patients with severe asthma with chronic rhinosinusitis in Saudi Arabia: patients with nasal polyps versus those without nasal polyps.

BACKGROUND: This study's purposes were to evaluate the impact of biological therapies on outcomes in patients with severe asthma (SA) and chronic rhinosinusitis (CRS) and to compare these effects among those with NP (CRSwNP) versus those without NP (CRSsNP) in the "real-world" setting in Saudi Arabian patients. METHODS: From March to September 2022, a retrospective observational cohort study was undertaken at the severe asthma clinics of the Armed Forces Hospital-Southern Region (AFHSR) and King Khalid University Hospital, Abha, Saudi Arabia, to delineate the effects of dupilumab therapy. Outcomes were assessed, including clinical outcomes, FEV1, and laboratory findings before and one year after dupilumab. Post-therapy effects were compared between CRSwNP and CRSsNP. RESULTS: Fifty subjects were enrolled, with a mean age of 46.56. There were 27 (54%) females and 23(46%) males. Significant improvements in clinical parameters (frequency of asthma exacerbations and hospitalizations, the use of OCs, anosmia, SNOTT-22, and the ACT), FEV1, and laboratory ones (serum IgE and eosinophilic count) were observed 6 and 12 months after using dupilumab (p < 0.001), respectively. However, after 12 months of dupilumab therapy, there were no significant differences between those with and without NP with regards to clinical (anosmia, ACT, and OCs use), laboratory (eosinophilic count, serum IgE level) parameters, and FEV1%. CONCLUSIONS: Patients with CRS experienced significant improvements in clinical, FEV1, and laboratory outcomes after dupilumab therapy. However, these improvements were not maintained when comparing CRSwNP with CRSsNP. There were no significant differences between those with and without NP regarding ACT and OCs use or laboratory (eosinophilic count, serum IgE level) parameters. Further prospective multicenter studies are warranted.

Resveratrol reduces oxidative damage and inflammation in mice infected with Trichinella spiralis.

Trichinellosis is a serious food-borne zoonotic infection of cosmopolitan distribution. Currently, treatment for trichinellosis is far from ideal. Given the important role of oxidative stress and immune-mediated inflammation in the pathogenesis of trichinellosis, this study was designed to evaluate the possible protective effects of resveratrol (RSV) during the intestinal and muscular phases of Trichinella spiralis infection in mice. The oral administration of RSV at a dose of 20 mg/kg once daily for two weeks resulted in significant reductions in both adult and larval counts; significant improvements in the redox status of the small intestine and muscles; a significant reduction in interleukin 4, pentraxin 3 and vascular endothelial growth factor expression; and the mitigation of intestinal and muscular inflammation. In conclusion, this study identifies RSV as a promising agent for the treatment of experimental trichinellosis, and more studies in experimental animals and humans are worth consideration.

Schistosoma mansoni and endocarditis: from egg to free DNA detection in Egyptian patients and infected BALB/c mice.

With the growing incidence of closed schistosomiasis and uncommon presentations, there is a risk of the infection rate being underestimated. A study in Japan reported an unexplained case of endocarditis that was finally diagnosed as a complex Schistosoma japonicum infection; in the absence of advanced techniques, the diagnosis was delayed. We therefore set out to explore the incidence of Schistosoma mansoni in endocarditis patients coming from areas of Egypt where S. mansoni is endemic. We also investigated histopathological changes in the cardiac valves and the presence of cell-free parasite DNA (CFPD) in cardiac tissues of laboratory mice infected with S. mansoni. The study included 186 patients with the manifestations of infective endocarditis. Eggs were detected in the stool samples of 5.91% of patients. Seropositivity was reported in 23.66% of patients and antigen was detected in the urine samples of 10.21%. Using real-time polymerase chain reaction (PCR), CFPD was detected in the blood of 6.98% of the endocarditis patients and 95% of the infected mice, while the cardiac samples of 45% of the mice tested positive for CFPD (means ± SD = 1390.2 ± 283.65, 2158.72 ± 1103.1 and 5.71 ± 2.91, respectively). Histopathological examination revealed abnormal collagen deposition, inflammatory cells and haemorrhagic pigmentation in the heart sections. Despite the low incidence of S. mansoni infection in the studied cohort, the presence of CFPD in the cardiac tissue of infected mice makes it necessary to: (1) investigate the hazards of CFPD deposition in endothelium-rich organs; and (2) test the potential of CFPD to trigger tissue inflammation, abnormal proliferation or genome integration.

Oral contraceptive pills: Risky or protective in case of Trichinella spiralis infection?

The aim of this study was to investigate how Trichinella spiralis infection can be affected by contraceptive pills in vivo. Methods included six groups of female Wistar rats; healthy, Trichinella infected, receiving combined contraceptive pills (COCPs), receiving progestin only pills (POPs), infected receiving COCPs and infected receiving POPs. Parasite burden was measured; adult worm counts, gravidity, larvae and reproductive capacity index). Histopathological examination, immunohistochemical detection of C-kit+ mast cells and Foxp3+ T-reg. cells in intestinal sections, eosinophils muscle infiltration and CPK level were performed. Rats infected and receiving COCPs showed a significant increase in parasitic burden, and infected receiving POPs showed a significant reduction compared to infected only, with a significant increase in nongravid females (Mean total worms=964.40±55.9, 742±52.63, 686±31.68, larvae/g=5030±198.75, 2490±143.18 and 4126±152,91, respectively). Intestinal sections from infected receiving COCPs showed intact mucosa (though the high inflammatory cells infiltrate), and significant increase in C-kit+ mast cells number and intensity (30.20±4.15 and 60.40±8.29), and Foxp3+ T-reg. cells (10±1.58). Infected receiving POPs showed a significantly less CPK (5886±574.40) and eosinophilic muscle infiltration (58±13.51). Oestrogen-containing pills established a favourable intestinal environment for Trichinella by enhancing Foxp+T-reg. cells and stabilizing C-kit+mast cells, while POPs gave a potential protection with less gravidity, larval burden and eosinophilic infiltrate.

Montelukast, a cysteinyl leukotriene receptor-1 antagonist protects against hippocampal injury induced by transient global cerebral ischemia and reperfusion in rats.

Cysteinyl leukotrienes (CysLTs) are potent pro-inflammatory and immune modulating lipid mediators involved in inflammatory diseases and were boosted in human brain after acute phase of cerebral ischemia. The antagonism of CysLTs receptors may offer protection against ischemic damage. Therefore it seemed interesting to study the possible neuroprotective effect of Montelukast, a CysLTR1 antagonist in global cerebral ischemia/reperfusion (IR) injury in rats. Global cerebral ischemia-reperfusion was induced by bilateral carotid artery occlusion for 15 min followed by 60 min reperfusion period. Animals were randomly allocated into three groups (n = 30 per group): Sham operated, I/R control and rats treated with montelukast (0.5 mg/kg, po) daily for 7 days then I/R was induced 1 h after the last dose of montelukast. After reperfusion rats were killed by decapitation, brains were removed and both hippocampi separated and the following biochemical parameters were estimated; lactate dehydrogenase activity, oxidative stress markers (lipid peroxides, nitric oxide and reduced glutathione), inflammatory markers (myeloperoxidase, tumor necrosis factor-alpha, nuclear factor kappa-B, interleukin-6 and interleukin-10), apoptotic biomarkers (caspase 3 and cytochrome C), neurotransmitters (glutamate, gamma aminobutyric acid), Cys-LTs contents and CysLT1 receptor expression; as well as total brain infarct size and histopathological examination of the hippocampus were assessed. Montelukast protected hippocampal tissue by reducing oxidative stress, inflammatory and apoptotic markers. Furthermore, it reduced glutamate and lactate dehydrogenase activity as well as infarct size elevated by I/R. These results were consistent with the histopathological findings. Montelukast showed a neuroprotective effects through antioxidant, anti-inflammatory and antiapoptotic mechanisms.

Impacts of cobalt and zinc on improving peanuts nutrient uptake, yield and irrigation water use efficiency under different irrigation levels.

The knowledge of proper fertigation across various irrigation levels is necessary for maximizing peanut yield and irrigation use efficiency in arid areas, and it also can effectively alleviate the risk of nutrient deficiency induced by water stress. This study evaluated the effectiveness of cobalt combined with two zinc application methods on peanut nutrient uptake, yield, and irrigation water use efficiency across varying irrigation levels. A split-split plot experiment was carried out in 2021 and 2022. Three peanut gross water requirement (GWR) levels (100%, 80%, and 60%) were designated for main plots. Subplots featured plants treated with either 0 or 7.5 mg L-1 of cobalt. The sub-sub plots assessed chelated zinc effects at rates of 0 and 2 g L-1 via foliar and soil applications. In comparison to the control (100% GWR), nutrient uptake decreased, with sodium being the exception, and there was an increase in soil pH at 60% GWR. The results showed also significant reductions in yield and water use by approximately 60.3% and 38.1%, respectively. At this irrigation level, applying zinc via soil, either alone or combined with cobalt, led to significant yield increases of 89.7% and 191.3% relative to the control. Also, it's crucial to note that cobalt application negatively affected iron and copper at 60% GWR, but this impact was lessened with soil-applied zinc. Hence, under a similar circumstance, treating stressed peanut plants with additional foliar applications of iron + copper and applying zinc via soil, could enhance nutrient uptake and improve yield. On the other hand, at 80% GWR, a combination of foliar-applied zinc and cobalt, had a tremendous impact on the absorption of (nitrogen, phosphorus, magnesium, and zinc), resulting in enhanced agronomic traits and decreased water losses. Additionally, at this irrigation level, foliar zinc application alone yielded a 32.4% increase compared to the 80% GWR control. When combined with cobalt, there was a 70.0% surge in water use. Based on this knowledge, the study suggests using 80% GWR and treating peanut plants with a combination of foliar-applied zinc and cobalt. This strategy aids plants in countering the adverse effects of water stress, ultimately leading to enhanced yield and irrigation water use efficiency.

Stimulating growth, root quality, and yield of carrots cultivated under full and limited irrigation levels by humic and potassium applications.

Water stress poses a significant challenge for carrot cultivation, leading to decreased yield and inefficient water use efficiency. Therefore, it is crucial to provide plants with suitable supplements that enhance their stress resistance. In this study, we investigated the effectiveness of humic and potassium applications on carrot growth, yield characteristics, root quality, and water use efficiency under varying irrigation levels. A split-split plot experiment was conducted, with two levels of gross water requirements (GWR) (100% and 80%) assigned to the main plots. The subplots were treated with humic acid through foliar application (Hsp) or soil drenching (Hgd). The sub-subplots were further divided to assess the impact of foliar potassium sources (potassium humate, Kh) and mineral applications (potassium sulfate, K2SO4). The results revealed a substantial reduction in carrot yield under limited irrigation, reaching about 32.2% lower than under GWR100%. Therefore, under limited irrigation conditions, the combined application of Hgd and K2SO4 resulted in a significant yield increase of 78.9% compared to the control under GWR80%. Conversely, under GWR100%, the highest average yield was achieved by applying either Hsp and Kh or Hsp and K2SO4, resulting in yields of 35,833 kg ha-1 and 40,183 kg ha-1, respectively. However, the combination of Hgd and Kh negatively affected the yield under both GWR100% and GWR80%. Nonetheless, applying Kh in combination with Hgd under GWR80% led to improved nitrogen, phosphorus, potassium, potassium/sodium ratio, and total sugar concentrations, while reducing sodium content in carrot roots. Based on this study, it is recommended to adopt GWR80% and treat plants with a combination of Hgd and foliar K2SO4. This approach can help plants overcome the negative effects of water stress, improve yield and root quality, and achieve optimal water use efficiency.

Impact of viral co-infection on clinical outcomes and mortality of COVID-19 patients: a study from Saudi Arabia.

Background: In COVID-19 patients undetected co-infections may have severe clinical implications associated with prolonged hospitalization, ICU admission, and mortality. Therefore, we aimed to investigate the impact of viral coinfections on the outcomes of hospitalized patients with COVID-19 in a large tertiary Saudi Arabian Hospital. Methods: A total of 178 adult patients with confirmed SARS-CoV-2 who were hospitalized at the Armed Forces Hospital Southern Region (AFHSR), Saudi Arabia, from March 1st to June 30th 2022, were enrolled. Real-time PCR for the detection of viral co­infections was carried out. Cases (SARS-CoV-2 with viral coinfections) and control (SARS-CoV-2 mono-infection) groups were compared. Results: 12/178 (7%) of enrolled COVID-19 patients had viral coinfections. 82/178 (46%) of patients were males. 58% of patients had comorbidities. During the study period, 4/12 (33%) and 21/166 (13%) cases and control patients died, p=0.047, respectively. Duration of hospitalization was the only significant independent factor associated with SARS-CoV-2 coinfections, OR 1.140, 95% CI 1.020-1.274, p=0.021. Conclusions: The findings of this study from a large tertiary Saudi Arabian Center revealed a prevalence of 7% for SARS-CoV-2 viral coinfections. SARS-CoV-2 coinfected patients had a significantly prolonged duration of hospitalization and higher mortality than those with SARS-CoV-2 alone. Future studies are needed.

Utility of the 4C ISARIC mortality score in hospitalized COVID-19 patients at a large tertiary Saudi Arabian center.

Background: The International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) 4C mortality score has been used before as a valuable tool for predicting mortality in COVID-19 patients. We aimed to address the utility of the 4C score in a well-defined Saudi population with COVID-19 admitted to a large tertiary referral hospital in Saudi Arabia. Methods: A retrospective study was conducted that included all adults COVID­19 patients admitted to the Armed Forces Hospital Southern Region (AFHSR), between January 2021 and September 2022. The receiver operating characteristic (ROC) curve depicted the diagnostic performance of the 4C Score for mortality prediction. Results: A total of 1,853 patients were enrolled. The ROC curve of the 4C score had an area under the curve of 0.73 (95% CI: 0.702-0.758), p<0.001. The sensitivity and specificity with scores >8 were 80% and 58%, respectively, the positive and negative predictive values were 28% and 93%, respectively. Three hundred and sixteen (17.1%), 638 (34.4%), 814 (43.9%), and 85 (4.6%) patients had low, intermediate, high, and very high values, respectively. There were significant differences between survivors and non-survivors with regard to all variables used in the calculation of the 4C score. Multivariable logistic regression analysis revealed that all components of the 4C score, except gender and O2 saturation, were independent significant predictors of mortality. Conclusions: Our data support previous international and Saudi studies that the 4C mortality score is a reliable tool with good sensitivity and specificity in the mortality prediction of COVID-19 patients. All components of the 4C score, except gender and O2 saturation, were independent significant predictors of mortality. Within the 4C score, odds ratios increased proportionately with an increase in the score value. Future multi-center prospective studies are warranted.

Burden of Transport-Related Injuries in the Eastern Mediterranean Region: A Systematic Analysis for the Global Burden of Disease Study 2017.

BACKGROUND: Transport-related injuries (TIs) are a substantial public health concern for all regions of the world. The present study quantified the burden of TIs and deaths in the Eastern Mediterranean region (EMR) in 2017 by sex and age. METHODS: TIs and deaths were estimated by age, sex, country, and year using Cause of Death Ensemble modelling (CODEm) and DisMod-MR 2.1. Disability-adjusted life years (DALYs), which quantify the total burden of years lost due to premature death or disability, were also estimated per 100000 population. All estimates were reported along with their corresponding 95% uncertainty intervals (UIs). RESULTS: In 2017, there were 5.5 million (UI 4.9-6.2) transport-related incident cases in the EMR - a substantial increase from 1990 (2.8 million; UI 2.5-3.1). The age-standardized incidence rate for the EMR in 2017 was 787 (UI 705.5-876.2) per 100000, which has not changed significantly since 1990 (-0.9%; UI -4.7 to 3). These rates differed remarkably between countries, such that Oman (1303.9; UI 1167.3-1441.5) and Palestine (486.5; UI 434.5-545.9) had the highest and lowest age-standardized incidence rates per 100000, respectively. In 2017, there were 185.3 thousand (UI 170.8-200.6) transport-related fatalities in the EMR - a substantial increase since 1990 (140.4 thousand; UI 118.7-156.9). The age-standardized death rate for the EMR in 2017 was 29.5 (UI 27.1-31.9) per 100000, which was 30.5% lower than that found in 1990 (42.5; UI 36.8-47.3). In 2017, Somalia (54; UI 30-77.4) and Lebanon (7.1; UI 4.8-8.6) had the highest and lowest age-standardized death rates per 100,000, respectively. The age-standardised DALY rate for the EMR in 2017 was 1,528.8 (UI 1412.5-1651.3) per 100000, which was 34.4% lower than that found in 1990 (2,331.3; UI 1,993.1-2,589.9). In 2017, the highest DALY rate was found in Pakistan (3454121; UI 2297890- 4342908) and the lowest was found in Bahrain (8616; UI 7670-9751). CONCLUSION: The present study shows that while road traffic has become relatively safer (measured by deaths and DALYs per 100000 population), the number of transport-related fatalities in the EMR is growing and needs to be addressed urgently.

Predicting the environmental suitability for onchocerciasis in Africa as an aid to elimination planning.

Recent evidence suggests that, in some foci, elimination of onchocerciasis from Africa may be feasible with mass drug administration (MDA) of ivermectin. To achieve continental elimination of transmission, mapping surveys will need to be conducted across all implementation units (IUs) for which endemicity status is currently unknown. Using boosted regression tree models with optimised hyperparameter selection, we estimated environmental suitability for onchocerciasis at the 5 × 5-km resolution across Africa. In order to classify IUs that include locations that are environmentally suitable, we used receiver operating characteristic (ROC) analysis to identify an optimal threshold for suitability concordant with locations where onchocerciasis has been previously detected. This threshold value was then used to classify IUs (more suitable or less suitable) based on the location within the IU with the largest mean prediction. Mean estimates of environmental suitability suggest large areas across West and Central Africa, as well as focal areas of East Africa, are suitable for onchocerciasis transmission, consistent with the presence of current control and elimination of transmission efforts. The ROC analysis identified a mean environmental suitability index of 0·71 as a threshold to classify based on the location with the largest mean prediction within the IU. Of the IUs considered for mapping surveys, 50·2% exceed this threshold for suitability in at least one 5 × 5-km location. The formidable scale of data collection required to map onchocerciasis endemicity across the African continent presents an opportunity to use spatial data to identify areas likely to be suitable for onchocerciasis transmission. National onchocerciasis elimination programmes may wish to consider prioritising these IUs for mapping surveys as human resources, laboratory capacity, and programmatic schedules may constrain survey implementation, and possibly delaying MDA initiation in areas that would ultimately qualify.

Atorvastatin in nano-particulate formulation abates muscle and liver affliction when coalesced with coenzyme Q10 and/or vitamin E in hyperlipidemic rats.

AIMS: Statins are the most widely used to lower elevated low-density lipoprotein levels and preventing cardiovascular diseases in humans. However, about 20% of patients treated with this medication suffer from statin-related myalgia. To this end, this study investigated the potential effect of nano-particulate formulation in alleviating the muscles and liver damage either alone or when co-administered with nano coenzyme Q10 and nano vitamin E. MATERIALS AND METHODS: Male Wistar rats were fed normal diet or high-fat diet for 12 weeks, following which rats were treated with either (i) atorvastatin (5 or 20 mg/kg/day, p.o.) or (ii) atorvastatin with CoQ10 (10 mg/kg/day, p.o.) (iii) and/or vitamin E (30 mg/kg/day, p.o.) in free particle or nanoparticle forms for another 4 weeks. In all rats, serum total cholesterol (CH), triglycerides (TGs), low (LDL) and high (HDL) density lipoproteins, alanine (ALT) and aspartate (AST) transaminases, alkaline phosphatase (ALP), creatine kinase (CK), albumin (ALB), as well as hepatic malondialdehyde (MDA) and antioxidants "reduced glutathione (GSH) and superoxide dismutase (SOD)" were measured. Additionally quadriceps muscles and liver tissues were used for histopathological examination. KEY FINDINGS: The antihyperlipidemic effect of statins was not altered when formulated as nanoparticles; albeit the former showed a prominent reduction in the liver and muscle enzymes and histopathological alterations together with a marked decline in the oxidative stress as compared to the free particulate form. These results were augmented when atorvastatin was combined with CoQ10 and/or Vit.E. SIGNIFICANCE: Nanoparticulate formulation alleviated the statins induced liver and muscle damage especially when combined with CoQ10 and/or Vit.E.

Ischemic preconditioning and postconditioning alleviates hippocampal tissue damage through abrogation of apoptosis modulated by oxidative stress and inflammation during transient global cerebral ischemia-reperfusion in rats.

INTRODUCTION: It has been argued recently that ischemic preconditioning (IPre) and postconditioning (IPost) have beneficial effects in many ischemic disorders however; their effects on global ischemia/reperfusion (I/R) are poorly understood. Thus, the present work aimed to study the possible mechanisms underlying the neuroprotective effects of IPre and IPost. METHODS: Animals were randomly allocated into 4 groups (n = 30): (1) Sham operated (SO); (2) I/R group, animals were subjected to 15 min global ischemia followed by 60 min reperfusion; (3) IPre, animals were subjected to 3 episodes of 5 min ischemia followed by 10 min reperfusion before I/R; (4) IPost, animals were subjected to three episodes of 10s of ischemia and 10s of reperfusion after the period of ischemia followed by a 60 min reperfusion period. Lactate dehydrogenase activity, oxidative stress, inflammatory and apoptotic biomarkers, as well as neurotransmitters, infarct size and histopathological examination were assessed. RESULTS: I/R induced hippocampal damage through increasing oxidative stress, inflammatory, excitotoxic and apoptotic markers as well as lactate dehydrogenase activity and infarct size. Both, IPre and IPost attenuated most markers induced by I/R. CONCLUSIONS: IPre and IPost neuroprotective effects can be explained through their anti-oxidant, anti-inflammatory and anti-apoptotic mechanisms.

Flow cytofluorometric characterization of bovine blood and milk leukocytes.

Flow cytometry and sorting proved to be a rapid method that facilitated the identification of different leukocyte populations in bovine blood and milk. After briefly incubating whole blood and milk samples in a hypotonic phosphate buffer, containing supravital acridine orange, 5 classes of leukocytes were found in the blood (lymphocytes, neutrophils, eosinophils, basophils, and monocytes) and 4 in the milk (lymphocytes, neutrophils, monocytes, and macrophages) by flow cytometry. Cells were morphologically identified by fluorescent microscopy after flow cytometric sorting and by light microscopy after Papanicolaous staining. Udder parenchymal and ductal tissue cells (secretory and epithelial cells) were not found in the milk samples evaluated. Large differences in the total and differential cell counts were found in the different milk secretions.

Total dissolved and particulate lead in the Western Harbor of Alexandria, a Mediterranean basin under stress.

The Western Harbor of Alexandria, the largest harbor of Egypt on the Mediterranean Sea, receives different internal and external untreated pollutants affecting dramatically its water, sediments and biota. Surface and bottom water samples were collected bimonthly from this harbor for studying vertical, regional and monthly distributions of total suspended matter (TSM), total dissolved lead (TDPb) and total particulate lead (TPPb). The high surface TSM values coincided with air-borne dust, organic aggregates, plankton productivity and discharged wastes. The high TSM averages in winter resulted mainly from turbulence of the water column by wind action. The highest averages of TDPb in the petroleum and coal basins in the Western Harbor reflect their effects on the water column, while the lowest averages of TDPb and TPPb were found at a location far away from pollution sources. For the water column, the maximum and minimum monthly averages of TPPb and TDPb respectively in June reflect the increase in the rate of lead uptake by phytoplankton abundant in summer, favored by temperature elevation. The annual mean concentration of TPPb was nearly double that of TDPb, indicating that lead was transported to the Western Harbor mainly in particulate form. This reflects the high TSM content in the harbor water onto which a considerable part of lead was adsorbed.

[Adaptation to hypotension may involve the cerebral hemispheres]. / L'adaptation à l'hypotension peut mettre en jeu les hémisphères cérébraux.

Arterial vasodilatation was obtained by a slow injection of nicardipine (0.1 microgram/20 min) to normotensive Long Evans rats. Reflex tachycardia was a consequence of a sympathetic activation as labetalol injected prior to nicardipine prevented the calcium antagonist-induced heart rate changes. The slope of the mean blood pressure (mmHg) - heart period (msec) curve was reproducible after a 75 min interval. This index of baroreflex sensitivity was calculated before and after a transient cerebral ischemia. Hemispheric ischemia was induced by electrocauterization of the vertebral arteries and a transient occlusion of the common carotid arteries for 10 min. Brainstem perfusion was maintained with this protocol. The second dose of nicardipine was injected 15 min after recirculation. The tachycardic response to the vasodilatation was markedly reduced after ischemia (1st slope: 0.48 +/- 0.05 msec/mmHg, 2nd slope: 0.12 +/- 0.05 msec/mmHg, n = 12, p less than 0.001, paired t test). We conclude that nicardipine injection is applicable to the study of baroreflex sensitivity in rats. The impairment of baroreflex sensitivity after a transient hemispheric ischemia could reflect a hemispheric interference with brainstem cardiovascular centres involved in the baroreceptor-heart rate reflex.

Ischaemia of the insular cortex increases the vagal contribution to the baroreceptor reflex in the rat.

Neurones in the insular cortex have been shown to innervate medullary autonomic nuclei. Occlusion of the stem of the left proximal middle cerebral artery in rats caused a lesion in the insular and adjacent lateral frontoparietal cortices. Nine and 10 days after lesioning or sham operation, we examined the relationship between mean blood pressure and the heart rate in conscious rats, using the steady-state method. Individual contributions to blood pressure from the cardiac vagus and sympathetic nerves were determined after the administration of atenolol and methylatropine, respectively. Lesioning the insular cortex did not affect mean blood pressure or the heart rate. However, the lesion selectively enhanced the reflex vagal bradycardia that occurred when blood pressure was artificially elevated. There was no effect on the sympathetic heart rate range. These observations suggest that the unilateral cortical lesion chronically affected the baroreceptor control of the heart rate through mechanisms affecting the vagus.

Dissolved organic matter status in Damietta estuary of the Nile.

The seasonal distribution of dissolved organic matter (DOM) in Damietta estuary of the Nile was investigated to show the influence of organic pollution. The DOM values increased generally with depth. The vertical values of DOM varied from 0.23-9.97 mg O/l. The average DOM values gave noticeable local variations in each month and pronounced monthly variations at each station. The maximum monthly average value in August coincided principally with elevation of temperature and the minimum in December is due mainly to the drop in temperature. The direct effect of pollution, in increasing the DOM content in the estuary, decreases relatively towards the sea, as indicated by the minimum regional average DOM value at the mouth of Damietta estuary. An inverse relationship was found generally between the averages of DOM and those of dissolved oxygen.

Is gastric ulceration different in normal and malnourished rats?

Protein malnutrition can adversely affect all tissues. The aim of the present study was to test the hypothesis that protein deprivation influences gastric ulcer formation, as well as metabolism and organ growth, in rats. In the present study, there was a significant reduction in the body and organ weight of rats fed a low-protein diet (P<0.001). Malnourished rats were less susceptible to ulceration of the gastric mucosa in ethanol and indomethacin models of acute gastric ulcers when compared with rats fed a normoproteic diet (17 % protein). Mucus production and prostaglandin E2 formation increased in malnourished rats, possibly explaining the lower number of acute ulcers in these animals. Pylorus ligature altered gastric juice composition (increased pH and gastric volume, and decreased total acid concentration) in the animal group fed a low-protein diet compared with the group fed a diet containing 17 % protein (P<0.05). The gastric mucosa was more damaged in malnourished rats than in normal rats evaluated for 14 d after acetic acid injection (P<0.001). Malnourished rats exhibited resistance to acute gastric lesions, owing to an increase in prostaglandin GE2 release and mucus secretion, which protected their gastric mucosa. This phenomenon was not seen in subchronic gastric ulceration.