Egg Parasitoids of Dalbulus maidis (Hemiptera: Cicadellidae) Within Maize Agroecosystems and in the Edge Zones of Maize Fields, and on Maize Varieties During the Wet Season in Mexico.

Little is known about Dalbulus maidis (DeLong) egg parasitoids within maize fields, in the edge zones that surround these fields, and the parasitism on D. maidis eggs oviposited on different maize varieties. The objectives of the present study were first to understand which egg parasitoid species attack D. maidis eggs within maize fields and in the surrounding edge zones, and second, to compare parasitism on two maize varieties (land race Ancho-pozolero and hybrid Tigre-Asgrow) during the maize-growing wet season. We used maize plants with sentinel eggs to attract the egg parasitoids in two consecutive wet seasons, in 2015 and 2016. In 2015, Anagrus sp. (Hymenoptera: Mymaridae) and Paracentrobia sp. (Hymenoptera: Trichogrammatidae) parasitized D. maidis eggs within the maize field and on its edges. However, much more parasitism was seen within the maize agroecosystem than in the maize edge zones. In 2016, two Mymaridae species, Anagrus columbi Perkins and Anagrus sp, and two Trichogrammatidae genera, Pseudoligosita sp. and Paracentrobia sp., attacked the D. maidis eggs laid on maize hybrids but not those oviposited on the maize land race. Our findings indicate that parasitism of corn leafhopper eggs differs with agroecosystem location and maize varieties.

The use of an algorithm for prophylactic mesh use in high risk patients reduces the incidence of incisional hernia following laparotomy for colorectal cancer resection. / Un algoritmo para la colocación de malla profiláctica en pacientes de riesgo reduce la incidencia de hernia incisional tras laparotomía por cáncer colorrectal.

OBJECTIVE: Incisional hernia (IH) after colorectal surgery is highly prevalent. The objective of this study is to assess the utility of an algorithm to decide on mesh augmentation after a midline laparotomy for colorectal resection to prevent IH in high-risk patients. METHODS: A prospective study was conducted including all patients undergoing a midline laparotomy for colorectal resection between January 2011 and June 2014, after the implementation of a decision algorithm for prophylactic mesh augmentation in selected high-risk patients. Intention-to-treat analyses were conducted between patients in which the algorithm was correctly applied and those in which it was not. RESULTS: From the 235 patients analysed, the algorithm was followed in 166 patients, the resting 69 cases were used as a control group. From an initial adherence to the algorithm of 40% in the first semester, a 90.3% adherence was achieved in the seventh semester. The incidence of IH decreased as the adherence to the algorithm increased (from 28 to 0%) with a time-related correlation (R2=0.781). A statistically significant reduction in IH incidence was demonstrated in high-risk groups in which the algorithm was correctly applied (10,2 vs. 46,3%; p=0,0001; OR: 7,58;95%; CI: 3,8-15). Survival analysis showed that the differences remained constant during follow-up. CONCLUSION: The implementation of the algorithm reduces the incidence of IH in high-risk patients. The adherence to the algorithm also correlates with a decrease in the incidence of IH.

Effects of voluntary slow breathing on heart rate and heart rate variability: A systematic review and a meta-analysis.

Voluntary slow breathing (VSB) is used as a prevention technique to support physical and mental health, given it is suggested to influence the parasympathetic nervous system (PNS). However, to date, no comprehensive quantitative review exists to support or refute this claim. We address this through a systematic review and meta-analysis of the effects of VSB on heart rate variability (HRV). Specifically, we focus on HRV parameters indexing PNS activity regulating cardiac functioning, referred to as vagally-mediated (vm)HRV: (1) during the breathing session (i.e., DURING), (2) immediately after one training session (i.e., IM-AFTER1), as well as (3) after a multi-session intervention (i.e., AFTER-INT). From the 1842 selected abstracts, 223 studies were suitable for inclusion (172 DURING, 16 IM-AFTER1, and 49 AFTER-INT). Results indicate increases in vmHRV with VSB, DURING, IM-AFTER1, and AFTER-INT. Given the involvement of the PNS in a large range of health-related outcomes and conditions, VSB exercises could be advised as a low-tech and low-cost technique to use in prevention and adjunct treatment purposes, with few adverse effects expected.

Application of spectroscopic techniques: ICP-OES, LA-ICP-MS and chemometric methods for studying the relationships between trace elements in clinical samples from patients with atherosclerosis obliterans.

The study was aimed to evaluate the influence of the vascular disease, atherosclerotic obliterans (AO), on the location and concentration of elements in the arterial wall and serum. Use of a modern method for studying element's concentration and distribution in samples of clinical material, i.e. laser ablation inductively coupled plasma mass spectrometry, is presented. Elements are not equally distributed between the inner (intima) and the outer (media + adventitia) layer of the arterial wall. Among the studied elements, calcium was found to have an unquestionable role in the calcification of the wall. Increased concentration of calcium found in the inner part of the atherosclerotic arterial wall and in the plaque, as compared to the control arterial wall samples, demonstrates the unquestionable role of this element in the calcification of the wall observed in AO. Applied chemometric methods were useful for demonstrating the differences in the element's concentration in blood serum and the arterial wall samples between AO and the control group.

The importance of ceruloplasmin oxidase activity in patients with chronic lower limb atherosclerotic ischemia.

AIM: Inflammatory reactions accompanying ischemia increase the cytokine synthesis what leads to the increase in serum ceruloplasmin (Cp) concentration and activity. The aim of the study was to evaluate the association between serum Cp oxidase concentration and activity and the grade of lower extremity ischemia. Moreover, the correlation of Cp concentration and activity with the levels of interleukin 6 (IL-6), C-reacting protein (CRP), and a-1-acid glycoprotein (AGP) in serum was studied. METHODS: Two groups of patients were examined: 15 patients with moderate (MI) and 32 patients with critical ischemia (CI) of the lower extremities. Cp oxidase activity was measured spectrophotometrically, after incubation with o-dianisidine. The concentration of IL-6 was measured with the ELISA method, and Cp, CRP and AGP concentration by rocket immunoelectrophoresis. RESULTS: Significant increase in Cp oxidase concentration and activity was observed in patients with critical limb ischemia (median: 164.8 U/L), especially in patients with necrotic changes (median: 216.6 U/L). Cp oxidase activity was dependent on its concentration in patients with critical limb ischemia with necrotic changes (r=0.56; P<0.01). In patients with critical limb ischemia, the increase in Cp concentration and activity correlated significantly with CRP concentration (r=0.46; P=0.0007) (r=0.62; P=0.0001), respectively. CONCLUSION: Concentration and the oxidase activity of Cp depend of the degree of lower extremity ischemia and correlates with the major markers of inflammation, such as CRP. Critical limb ischemia induces the inflammatory reaction triggering the increase in IL-6 and of acute phase protein production. These processes lead to the increase in Cp oxidase activity dependent of Cp and CRP concentration.

Altered elastase-alpha1-antitrypsin balance in the blood of patients with chronic venous disease.

OBJECTIVES: Although leukocyte elastase is suspected to be involved in the damage of vein wall during chronic venous disease, the equilibrium between this protease and its inhibitor, alpha1-antitrypsin, has not yet been evaluated. The aim of the present study was to determine the relationship between leukocyte elastase and alpha1-antitrypsin, in the blood of patients with chronic venous disease. PATIENTS AND METHODS: The concentration and the activity of leukocyte elastase along with the activity of alpha1-antitrypsin were evaluated in the blood of 55 chronic venous disease patients. The results were compared with those obtained in 33 healthy age and sex-matched volunteers. RESULTS: A significant decrease in the leukocyte elastase activity that correlated with an increased alpha1-antitrypsin activity was observed in the serum of patients with mild clinical symptoms of chronic venous disease. CONCLUSIONS: The results of the study did not confirm a hypothesis about an important role of proteolytic activity of leukocyte elastase in the vein wall injury mechanism. They show that the leukocyte elastase-alpha1-antitrypsin balance is rather shifted toward antiprotease activity, especially in an early stage of chronic venous disease.

Serum magnesium, copper and zinc concentration changes in lower limb ischemia and postoperative treatment.

A prolonged state of ischemia of the lower limbs may affect the balance of some metal ion concentrations in blood. Ischemia of a critical degree, surgery and complicated postoperative periods invoke an inflammatory response, increased production of interleukin-6 (IL-6) and acute phase proteins (APhP) as a response to tissue destruction. The aim of the present study was to investigate the modification of Mg, Cu and Zn concentrations in the serum of patients with atherosclerosis obliterans (AO) before surgery and during the postoperative treatment, and the effect of chronic ischemia of the lower limbs on the relationship between the elements. The group studied consisted of 54 men with chronic ischemia of the lower limbs due to AO. The mean value of serum Mg concentration in men with AO was found to be significantly lower, and that of Cu to be higher, in comparison with the control group. In critical ischemia, the mean serum Cu concentration and the ratio Cu/Zn were found higher than in moderate ischemia. The postoperative treatment results in changes in Cu and Zn concentrations in the AO group that are inversely related to the levels before surgery.

Oxidase activity of ceruloplasmin and concentrations of copper and zinc in serum in chronic arterial occlusion of the lower limbs.

The presence of ischaemic tissue excites an inflammatory reaction and synthesis of acute phase proteins (APhPs). Ceruloplasmin (Cp) protein binds 90% of the copper in plasma and it is one of the positive APhPs, and its concentration increases in infection, inflammation or necrosis. The study presents the relationship of the oxidase activity of Cp and concentrations of Cu and Zn in serum of men with different degrees of ischaemia of the lower limbs. The subjects were 32 men with chronic arterial occlusion (AO) of the lower limbs. The oxidase activity of Cp was measured in serum with o-dianisidine as a substrate. Concentrations of Cu and Zn were determined by using atomic absorption spectrometry. The mean activity of Cp in serum in AO (173 +/- 69.2 U/l) was higher as compared with the control group (123.7 +/- 28.6 U/l), and in men with critical ischaemia (> or = 194.8 U/l) than in men with a moderate level of ischaemia (109.3 +/- 31.6 U/l). The mean concentrations of Cu and Zn in serum were found to be higher in AO (22.2 +/- 4.2 and 19.1 +/- 6.9 mumol/l, respectively) than in the control group (16.3 +/- 1.8 and 15.2 +/- 2.3 mumol/l), and in men with critical ischaemia (> or = 22.2 and 19.1 mumol/l) than in men with a moderate level of ischaemia (18.5 +/- 3.3 and 14.5 +/- 4.3 mumol/l). Significant positive correlation coefficients were calculated for the activities of Cp and concentrations of Cu in the control group (r = 0.86) and the AO group (r = 0.76), and low, but significant, correlations for Cp and Zn in the AO group (r = 0.66). The increase in the oxidase activity of Cp and concentration of Cu in serum in ischaemia is caused by the acute phase response. The relationship of Zn concentration and Cp activity in ischaemia is indirect and needs further study.

Relationship of calcium, magnesium, zinc and copper concentrations in the arterial wall and serum in atherosclerosis obliterans and aneurysm.

Changes in copper concentration in the arterial wall are important because of cross-linkage formation in collagen and elastin. The breakdown of the elastic layer is characteristic for aneurysm and is affected by the abnormalities in copper metabolism. This study was undertaken to evaluate Ca, Mg, Zn and Cu concentrations and their relationships in the arterial wall, serum and calcified plaque in atherosclerosis obliterans (AO) and abdominal aortic aneurysm (AA). Samples of the aorta wall were obtained at the endarterectomy in AO and the vascular reconstruction in AA. Elements were determined by means of atomic absorption spectrometry. Serum concentrations of Zn and Cu were higher and that of Ca lower in AO as compared to AA and the controls. Arterial concentrations of Zn, Cu and Mg were higher in AO as compared to AA. The ratios of element concentrations in serum (Ca/Mg, Ca/Zn and Mg/Cu) were higher in serum in AA than in AO. Positive correlations were calculated for Ca and Mg (r > or = 0.74), Ca and Zn (r > or = 0.73), Mg and Zn (r > or = 0.90) in the arterial wall in AO and AA. Low but significant correlation was calculated for Cu concentrations between serum and the arterial wall in AA (r = 0.43). Concentrations of Ca, Mg, Zn and Cu were higher in plaque than in the surrounding tissue. The results indicate differences in arterial and serum concentrations of Ca, Mg, Zn and Cu between AO and AA and the accumulation of these elements in the plaque rather than in the surrounding vascular tissue.

Serum glycerol ester hydrolase activity is related to zinc and copper concentrations in atherosclerosis obliterans and aneurysm.

Although the body status of zinc and copper in cardiovascular disease (CVD) has been shown to be important little is known about the effect of these trace element alterations on lipolytic enzyme activities in atherosclerosis human subjects. The aim of the present study was to evaluate the multiple relationships between lipase (GEH = glycerol ester hydrolase, EC 3.1.1.3) activity, zinc, copper and lipid concentrations in serum and the arterial wall of men with atherosclerosis obliterans (AO) and abdominal aortic aneurysm (AA). The mean concentrations of zinc and copper in serum were found to be higher in AO in comparison to AA. Low but significant correlation coefficients for zinc and lipase catalytic activity (r > or = 0.64) and lipase metabolic activity GEH/TAG (r > or = 0.67) were calculated in serum in AA. Multiple correlation coefficients (R) for three variables GEH-Zn-Cu were found to be significant for both AO and AA (R > or = 0.45 and 0.68, respectively) in serum but not in the arterial wall. Multiple relations for GEH/TAG-HDL-C (LDLC)-Zn(Cu) were found to be significant (R > or = 0.63) in serum in AA. The results indicate the influence of zinc and copper on the activity of lipase and lipid concentrations and suggest that the multiple relations may provide a better understanding of the role these elements play in atherosclerosis than relations between 2 substances.

Oxidase activity of ceruloplasmin and concentrations of copper and zinc in serum of cancer patients.

A balance between oxidant carcinogens and endogenous antioxidant defence is of particular relevance to the carcinogenesis. Ceruloplasmin (Cp) carries up to 90% of Cu in plasma and performs ferroxidase, antioxidant and amine oxidase activity. Cu and Zn, as trace elements, have been recognized to play an important role as cofactors of SOD. The study presents the relationship of the Cp oxidase activity and concentrations of Cu and Zn in serum of 62 patients with breast (BCA), lung (LCA), gastrointestinal (GICA) and gynecological (GYNCA) cancer. The Cp oxidase activity was determined in serum with o-dianisidine as a substrate. Cu and Zn concentrations in serum were measured by using atomic absorption spectrometry. The results of the study have shown significant increase in the mean serum Cp oxidase activity and total Cu concentrations in all patient groups compared with the control one. The total mean serum Zn concentration was found to be decreased only in LCA group as compared with the control. The effect of the cancer progress on the Cp oxidase activity and concentrations of Cu and Zn was observed within the group of all cancer patients (ALLCA) and within the GICA group. The only significant difference in Cu concentrations among various stages of the disease was observed in GICA between local and distant one. Significant positive correlation coefficients were caLculated for the Cp activity and Cu concentrations in the control group and all patients groups, also according to the cancer progress. Future research is needed to evaLuate the consequences of the elevation of the serum Cp oxidase activity and concentration of Cp, Cu and Zn for the host antioxidant-oxidant balance.

Copper and zinc concentrations and the activities of ceruloplasmin and superoxide dismutase in atherosclerosis obliterans.

The relationships among concentrations of copper and zinc, the oxidase activity of ceruloplasmin (Cp) in serum, and Cu,Zn-SOD (superoxide dismutase) activity in erythrocytes were investigated in men with atherosclerosis obliterans (AO) and a control group. The oxidase activity of Cp was measured with o-dianisidine dihydrochloride as a substrate, and Cu,Zn-SOD activity in erythrocytes by using the RANSOD kit. The lipid profile and uric acid concentration were determined in AO and control groups. The results showed higher copper and zinc concentrations in serum in the AO group (20.0+/-3.5 and 18.0+/-3.2 micromol/L, respectively) in comparison with the control group (15.6+/-2.3 and 14.7+/-1.9 micromol/L). The Cp activity in serum was higher in the AO group (174.2+/-61.8 U/L) than in the control group (93.7+/-33.9 U/L), and a significant difference was found in the activity of Cu,Zn-SOD in erythrocytes (2389+/-1396 and 1245+/-365 U/g Hb, respectively) between both groups. The activity of Cu,Zn-SOD was positively correlated with copper in the control group (r=0.73), but not in AO, and negatively with uric acid concentration (r= -0.63) in the AO group. The oxidase activity of Cp was correlated with copper, but not zinc, in AO and control groups (r> or =0.65). Negative correlation coefficients were calculated for uric acid and copper and zinc concentrations in the AO group (-r > or = 0.61). Increased copper concentrations and oxidase activity of Cp in serum in AO and the activity of Cu,Zn-SOD in erythrocytes could result from atherosclerotic disease, accompanied by chronic ischemia of a lower limb. These results suggest also that relationship between copper concentration and Cu,Zn-SOD activity in erythrocytes found in the serum of healthy subjects may be disturbed in pathologic conditions.

Analysis of serum copper and zinc concentrations in cancer patients.

Several studies have shown that plasma copper concentrations are increased in various carcinomas. Zinc acts as a cellular growth protector, including growth of neoplastic cells, and its deficiency was demonstrated to be involved in several stages of malignant transformation. However, the usefulness of the serum zinc and copper determinations in cancer prevention, detection, monitoring treatment, and prognosis requires further investigations. The aim of the present study was to compare the serum copper and zinc levels in patients with cancer of the lung (PC), breast (BC), gastrointestinal tract (GIC), and gynecological (GYNC) malignancy with progress of the disease. The results of the study have shown a significant increase in the mean total serum Cu levels and the serum Cu/Zn ratio in all patient groups with cancer compared to a control group. Increased mean serum concentrations and Cu/Zn ratios were found in the whole group (ALLC), and for the GIC and GYNC groups with local as well as metastasized (Meta) disease in comparison with the control group. The mean serum concentrations of Zn were decreased only in metastasized ALLC and GYNC groups.

A feasibility study of realtime telemedicine in Croatia using Internet videoconferencing.

We explored the feasibility of realtime telemedicine in Croatia using Internet videoconferencing. A 33 kbit/s link was established between a team of specialists in the General Hospital 'Sveti Duh' in Zagreb and a general practitioner's clinic in Selca, on the island of Brac. During a two-week study, 16 patients (median age 51 years) were studied. Twenty-one teleconsultations (seven initial and 14 follow-up visits) were conducted, 13 with a specialist in internal medicine, six with a surgeon and two with a neurologist. In 18 cases (86%) telemedicine successfully replaced hands-on examination. The mean duration of the teleconsultations was 7.2 min (initial visits 7.4 min, follow-up visits 7.1 min). Each computer system cost about US$700. The total connection cost for the study was US$4.95. The teleconsultations saved the patients US$272 in travel costs. We suggest forming a permanent on-line specialist service connected to networked clinics via the Internet to improve access to health-care in Croatia.

Un algoritmo para la colocación de malla profiláctica en pacientes de riesgo reduce la incidencia de hernia incisional tras laparotomía por cáncer colorrectal / The use of an algorithm for prophylactic mesh use in high risk patients reduces the incidence of incisional hernia following laparotomy for colorectal cancer resection

INTRODUCCIÓN: Existe una alta incidencia de hernia incisional (HI) tras cirugía de colon. El objetivo de este estudio fue analizar la utilidad de un algoritmo de decisión para la colocación de malla profiláctica tras laparotomía media por cáncer colorrectal en pacientes de riesgo. MÉTODOS: Se planteó un estudio prospectivo que incluyera a los pacientes intervenidos de cáncer colorrectal por laparotomía media entre enero de 2011 y junio de 2014, tras la implementación de un algoritmo de decisión para la colocación de malla profiláctica en pacientes seleccionados de alto riesgo. Se realizó análisis por intención de tratar entre los pacientes en los que se siguió correctamente el algoritmo y en los que no. RESULTADOS: De los 235 pacientes analizados, el algoritmo se siguió correctamente en 166 pacientes, los 69 restantes se usaron como grupo control. Partiendo de una adherencia inicial del 40% en el primer semestre del estudio, se logró llegar a un cumplimiento del 90,3% en el último semestre. La incidencia de HI disminuyó progresivamente a medida que aumentaba la adherencia (de 28 a 0%), con una correlación tiempo-dependiente (R2=0,781). Se logró una disminución estadísticamente significativa de HI en los grupos en los que el algoritmo se aplicó correctamente (10,2 vs. 46,3%; p = 0,0001; OR 7,58;95% IC: 3,8-15). El análisis de supervivencia demostró que las diferencias se mantuvieron constantes durante el seguimiento. CONCLUSIONES: La implementación del algoritmo redujo la incidencia de HI en pacientes de riesgo. La adherencia al algoritmo se correlaciona con el descenso en la incidencia de HI

OBJECTIVE: Incisional hernia (IH) after colorectal surgery is highly prevalent. The objective of this study is to assess the utility of an algorithm to decide on mesh augmentation after a midline laparotomy for colorectal resection to prevent IH in high-risk patients. METHODS: A prospective study was conducted including all patients undergoing a midline laparotomy for colorectal resection between January 2011 and June 2014, after the implementation of a decision algorithm for prophylactic mesh augmentation in selected high-risk patients. Intention-to-treat analyses were conducted between patients in which the algorithm was correctly applied and those in which it was not. RESULTS: From the 235 patients analysed, the algorithm was followed in 166 patients, the resting 69 cases were used as a control group. From an initial adherence to the algorithm of 40% in the first semester, a 90.3% adherence was achieved in the seventh semester. The incidence of IH decreased as the adherence to the algorithm increased (from 28 to 0%) with a time-related correlation (R2=0.781). A statistically significant reduction in IH incidence was demonstrated in high-risk groups in which the algorithm was correctly applied (10,2 vs. 46,3%; p = 0,0001; OR: 7,58;95%; CI: 3,8-15). Survival analysis showed that the differences remained constant during follow-up. CONCLUSION: The implementation of the algorithm reduces the incidence of IH in high-risk patients. The adherence to the algorithm also correlates with a decrease in the incidence of IH

Activities of copper,zinc-superoxide dismutase in erythrocytes and ceruloplasmin in serum in chronic ischemia of lower limbs.

Cu,Zn-superoxide dismutase is an endogenous scavanger of superoxide radicals (O(2)(*-)) which also induce the synthesis of this enzyme. Ceruloplasmin is an antioxidant and acute-phase reactant. Changes in the synthesis of both enzymes are related to the metabolism of copper and zinc. Concentrations of copper and zinc were previously found to be increased in the serum and arterial wall of atherosclerotic subjects. The aim of this study was to investigate the Cu,Zn-superoxide dismutase activity in erythrocytes and ceruloplasmin activity in serum, and to measure serum concentrations of copper, zinc, and malonyldialdehyde in patients with moderate and critical chronic ischemia of the lower limbs. A group of 26 patients with chronic arterial occlusion of the lower limbs was divided into two groups depending on the degree of ischemia: moderate and critical. Cu,Zn-superoxide dismutase activity in erythrocytes was measured using the RANSOD kit, the serum ceruloplasmin oxidase activity was determined with o-dianisidine as a substrate. Copper and zinc concentrations in serum were determined by atomic absorption spectrometry. There was an increase in the ceruloplasmin activity and serum copper concentration in critical ischemia (194.4+/-51.94 U/l and 23.5+/-4.2 micromol/l, respectively) compared with moderate ischemia (139.1+/-34.9 U/l and 18.5+/-2.0 micromol/l, respectively). The Cu,Zn-superoxide dismutase activity in erythrocytes was higher in moderate ischemia (2,657+/-1,564 U/g hemoglobin) than in controls (1,205+/- 353 U/g hemoglobin), but not different from critical ischemia. There was a negative correlation for Cu,Zn-superoxide dismutase and ceruloplasmin (r=-0.60, P

The interaction of cholinomimetics, peptides and compounds 48/80 on histamine secretion from the mast cell.

The mechanism of selective, non-immunological histamine release from mast cells, caused by various endogenous substances, is not clearly understood. Since in vivo experiments indicate that the local control of secretory cells is influenced by acetylcholine and peptides, we investigated whether the secretion of histamine is similarly regulated in the mast cell. Experiments were performed with peritoneal cavity cell suspensions (PCS) of the rat. The endogenous polypeptide substance P, compound 48/80 and a non-hydrolysable cholinomimetic agonist, carbachol, were used. The concentrations of the drugs were kept low to avoid non-specific histamine release caused by morphological damage of mast cells. It was found that: (1) carbachol (2 X 10(-5) M) did not release histamine from PCS, (2) substance P (6.5 X 10(-6) M) released histamine and this effect was increased by the addition of carbachol (2 X 10(-5) M); the effect of carbachol was inhibited by atropine , (3) carbachol (2 X 10(-5)M) did not increase histamine release caused by compound 48/80 (0.02 micrograms/ml). From these experiments it may be concluded that activation of peptidergic receptor(s) can cause histamine release from mast cells and that muscarinic agents may be involved in the regulation of the(se) receptor(s).