Prevalence of Rho-inactivating epidermal cell differentiation inhibitor toxins in clinical Staphylococcus aureus isolates

Staphylococcus aureus produces exotoxins of the epidermal cell differentiation inhibitor (EDIN) family that ADP-ribosylate and inactivate Rho GTPases. The prevalence of genes encoding EDIN in clinical and nasal isolates of S. aureus was investigated. Of the 196 clinical S. aureus isolates tested, 15 (7.8%) were positive for 1 edin gene, whereas of 81 nasal isolates tested, only 3 (3.7%) were edin positive. Of the total 18 edin-positive isolates, 16 (90%) carried edin-B and 2 (10%) carried edin-C, but none was positive for edin-A. All edin-positive strains could produce the respective EDIN protein. Pulsed-field gel electrophoresis analysis suggested that the edin-B-positive S. aureus isolates are derived from one clone, and the edin-C-positive isolates are derived from another clone. Given that toxins acting on Rho GTPases are considered to be important for bacterial virulence, the EDIN toxins of S. aureus should receive more attention in future studies.

How recombinant insulin analogs improve insulin therapy of diabetes mellitus: pathophysiology, clinical practice and recommendations

According to the latest prognoses, 300 million people are expected to suffer from diabetes (particularly type 2) in 2025; diabetes will become a new epidemics of the coming century. Therefore it is so important to get acquainted with the pathomechanism of diabetes-related disorders and the possibilities of effective treatment. During the last decade, numerous prospective epidemiological studies have been completed, which have considerably extended our knowledge of the pathomechanism of disturbances and their effect on late complications of diabetes. Resistance to insulin has an important role in the etiology of type 2 diabetes. However, there is substantial evidence indicating that impairment or regression of rapid insulin secretion phase at the early stage of the disease is a factor of no lesser importance. The lack of appropriate insulin concentration after the stimulation by food ingestion (first 30 min after the meal), leads to permanent, treatment-resistant hyperglycemia. The postulated attempts to obtain a 'nearly normoglycemic' condition, as well as the results of prospective epidemiological studies proving that achieving this aim improves the prognosis of diabetic patients, prompt the researchers to search for the drugs or treatment schedules, which could effectively restore the impaired insulin secretion, and its early phase in particular, in type 2 diabetes. Human insulin analogs and their pre-formulated commercially available mixtures seem very promising in this respect.

[Influence of pre-conception pregnancy planning in women with diabetes mellitus I on the number of spontaneous abortions and major congenital malformations in their children]

OBJECTIVE

The study assesses the relationship between pre-conception pregnancy planning and number of spontaneous abortions and major congenital malformations in their children.

MATERIALS AND METHODS

138 pregnancies in women with type 1 diabetes without complications or only with simple retinopathy (White B, C, D) were analyzed. Women were treated in the Outpatient Family Planning Center in Warsaw between 1988 and 1998. Thirty women were planning the pregnancy prior to conception, 108 registered already when pregnant. The groups compared did not differ statistically in age, duration of diabetes or diabetic angiopathy. Mean values of HbA1C in consecutive trimesters were: 6.40%, 5.84%, 5.67% in the group of patients planning the pregnancy and 6.99%, 6.29%, 6.15% in the non-planning group. The differences were statistically significant (p < 0.05, p < 0.05, p < 0.01).

RESULTS

In the pre-conception group there were no spontaneous abortions and no and major congenital malformations. Mean value of HbA1C in early pregnancy was significantly higher in women with spontaneous abortions than in the remaining women in the non-planning group (respectively 7.9% and 6.9%). Also, mean value of HbA1C in early pregnancy was significantly higher in women who gave birth to children with major congenital malformations than in women had healthy children (respectively 8.23% and 6.81%, p < 0.05).

CONCLUSION

Pre-conception pregnancy planning improves metabolic control during pregnancy and decreases the rate of spontaneous abortions and major congenital malformations.

[Prospective studies of diabetic retinopathy in a cohort of patients with type II diabetes mellitus]

To gain current data about epidemiology of diabetic retinopathy in a population of type 2 diabetics a long-term prospective study was started. The study included 1334 patients with type 2 diabetes mellitus registered in Warsaw regional Diabetes Center. The prevalence of any form of diabetic retinopathy in this group was 31.4% and proliferative retinopathy-1.3%. It was found that the patients with retinopathy had diabetes mellitus of longer duration, higher fasting and postprandial levels of glycemia and higher daily proteinuria in comparison with diabetics without retinopathy. Apart from that, a frequency of ischemic heart disease and lower extremity ischemic disease was higher in diabetics with retinopathy. 109 new cases of retinopathy were diagnosed during 3-year follow-up. The study allowed us to determine the current epidemiological parameters concerning diabetic retinopathy in type 2 diabetics and a set of parameters characterizing people at highest risk of a development of retinopathy.

[Microcirculatory evaluation of the early diabetic foot syndrome using laser doppler]

Recognition of early microcirculatory disturbances in feet of diabetics may facilitate the pathogenic interpretation of the diabetic foot syndrome, selection of the patients at risk of developing clinical problems and serve as the base for designing the preventive measures. This could be particularly true in diabetics with peripheral neuropathy. Therefore the study aimed at the assessment of functional parameters of the foot microcirculation in IDDM patients presenting signs of peripheral neuropathy but without any symptoms of the diabetic foot syndrome was undertaken. For comparison 20 IDDM subjects with the signs of peripheral neuropathy and 10 IDDM subjects without this complication were studied both clinically and metabolically. All of them underwent the examination of microcirculation of the feet with the use of Laser Doppler Flowmeter. The parameters measured were: resting blood flow, post-occlusive, hyperemic response, flow change after heating to 44 degrees C and the flow on dependency. In IDDM subjects with peripheral neuropathy the following functional microcirculatory abnormalities were found: delay and decrease in post-occlusive, hyperemic response (4.5 +/- 1.8 s in neuropathic vs 0.5 +/- 2.4 s in non-neuropathic IDDM patients), decrease of the peak flow (36 +/- 7.0 PU in non neuropathic vs 18 +/- 5.0 PU in neuropathic IDDM patients) and also impairment of the response of the skin flow to focal heating peak flow at 44 degrees C (48 +/- 7.0 PU vs 12 +/- 3.0 PU in non neuropathic IDDM patients). Also the venoarteriolar reflex measured as the ratio of resting to standing flow in the feet skin was significantly decreased (80% in non-neuropathic versus 35% in neuropathic IDDM patients).

CONCLUSION

Laser Doppler Flowmetry discovers the very early functional abnormalities in the microcirculation of the skin in the feet of IDDM with peripheral neuropathy, when none of the typical symptoms of the diabetic foot syndrome is present. It points to the significance of the relation between neuropathic and microcirculatory disturbances in the early pathogenesis of diabetic foot syndrome.

[Diabetes mellitus as a risk factor for atherosclerosis--a reminder of the facts]

Diabetes mellitus in all its forms is the pathological state, which includes the atherogenic mechanisms of intensive action. This results in a very significant increase of the incidence, morbidity and mortality due to atherosclerotic complications. Such negative relationship is observed since decades and everywhere. Atherosclerosis is the main case of death in the subpopulation of diabetics in the degree much higher than in the general population. Therefore the studies of the mechanisms of the atherogenic influence of diabetes mellitus also of the possibility of preventive and therapeutic interventions are of utmost importance. Many of such studies are documenting, that such interventions are effective in practice. Active prevention and early individual diagnosis of atherosclerotic risk appears as the affective approach. The bare fact of such possibility was reminded in the paper.

[Measurement of treatment efficacy in diabetes: effect of atherosclerosis prevention and general effects]

Numerous indirect and direct, long-term, well designate, multicenter studies are pointing to the fact, that intensification of the hypoglycemic therapy of diabetes mellitus and also the control of the non-hyperglycemic risk factors of atherosclerosis decrease the incidence, morbidity and mortality due to atherosclerosis complications in the subpopulation of diabetics type I as well as type II. This positive finding requires the objective monitoring of the quality of diabetes mellitus care. One has to be sure, that its activity exerts also the anti-atherogenic effect. The respective indices are presented using the suggestions of the experts committees of the European Association for the Study of Diabetes (EASD).

[Highly purified pig insulin (WO-S) preparations--properties and clinical application]

Suggestions are actual trends in insulin production are presented with special stress paid on preparations made by Polfa Tarchomin S.A. Therapeutical indications and practical described according to actual rules.

Rho is a negative regulator of human monocyte spreading

Monocyte spreading is a sequential series of events including cell flattening, formation of new actin structures and focal adhesions, as well as development of cytoplasmic projections. To investigate the involvement of the GTP-binding protein Rho in spreading, we treated human blood monocytes or PMA-stimulated U937 or THP1 cells with Clostridium botulinum C3-transferase (C3), which ADP-ribosylates and inactivates Rho in intact cells. The C3 treatment caused 1) a four- to fivefold increase in the number of THP1 cells that spread on fibronectin within 24 h of PMA stimulation, 2) a greater area covered by the spread cells, and 3) accelerated and enhanced development of macrophage-like filopodial and pseudopodial projections. Similar results were obtained with PMA-stimulated U937 cells and human blood monocytes. Furthermore, cell staining revealed disorganization of subcortical actin in C3-treated THP1 cells, whereas circular actin formations at the substrate-attached part of the cells and vinculin-containing focal complexes/adhesions were unaffected. Finally, we found a decrease in membrane-associated RhoA in normal spreading THP1 cells, which suggests endogenous inactivation of Rho and might provide an explanation for the acceleration of spreading caused by the C3-transferase. In conclusion, these results indicate that active Rho is an important, negative regulator of human monocyte spreading by maintaining cell tension and cortical actin organization.

Rho is a negative regulator of human monocyte spreading

Monocyte spreading is a sequential series of events including cell flattening, formation of new actin structures and focal adhesions, as well as development of cytoplasmic projections. To investigate the involvement of the GTP-binding protein Rho in spreading, we treated human blood monocytes or PMA-stimulated U937 or THP1 cells with Clostridium botulinum C3-transferase (C3), which ADP-ribosylates and inactivates Rho in intact cells. The C3 treatment caused 1) a four- to fivefold increase in the number of THP1 cells that spread on fibronectin within 24 h of PMA stimulation, 2) a greater area covered by the spread cells, and 3) accelerated and enhanced development of macrophage-like filopodial and pseudopodial projections. Similar results were obtained with PMA-stimulated U937 cells and human blood monocytes. Furthermore, cell staining revealed disorganization of subcortical actin in C3-treated THP1 cells, whereas circular actin formations at the substrate-attached part of the cells and vinculin-containing focal complexes/adhesions were unaffected. Finally, we found a decrease in membrane-associated RhoA in normal spreading THP1 cells, which suggests endogenous inactivation of Rho and might provide an explanation for the acceleration of spreading caused by the C3-transferase. In conclusion, these results indicate that active Rho is an important, negative regulator of human monocyte spreading by maintaining cell tension and cortical actin organization.

[Basal and reactive renin and aldosterone secretion in arterial hypertension of insulin dependent diabetics]

The aim of the study was to assess the significance of the renin-angiotensin-aldosterone system (R-A-A) in the pathogenesis of arterial hypertension in patients with diabetes type I (IDDM). Testing was accomplished in the hospital conditions in a group of 131 patients with long-term IDDM, who beside of diabetes mellitus and its chronic complications did not show any symptoms of additional diseases. The patients were divided in 5 groups (A-E) depending on the type of coexisting late diabetic complications. The control group was consisted of 20 healthy persons matched for sex and age. In each case the following tests were performed: measurement of blood pressure in succumbent position, daily profile of glycemia and glucosuria, Hb A1 level, ophthalmoscopy, functional assessment of kidney and autonomic system status. Tenin activity in plasma (ARO) and plasma aldosterone (ALD) were determined in basal (after 6 h of succumbent position) and after i.v. administration of 40 mg of furosemide and 3 h of standing position (reactive values). In all groups under study the significant decrease of average, basal and reactive ARO was found in comparison with the control group. This abnormality was the most distinct in subjects with diabetic nephropathy. The autonomic neuropathy was abolishing this tendency. The mean concentration ob basal ALD was in all diabetic subgroups similar as in the controls. The mean reactive ALD was however significantly decreased. In diabetes complicated by retinopathy the negative correlation between ARO and systolic, diastolic and mean blood pressure existed. In diabetes complicated by nephropathy the dependence between blood pressure and ARO and ALD was not found.(ABSTRACT TRUNCATED AT 250 WORDS)

[Principles of hypotension treatment in patients with diabetes]

Epidemiological studies have revealed, that elevated blood pressure is in diabetics 1.5-3.0-times more frequent that in general population. It is one of the most important factors increasing the morbidity and mortality due to small and big arteries disease. Hypotensive therapy should be commenced in diabetic persons earlier than in patients without diabetes mellitus. In many such diabetic patients blood pressure normalization could be obtained by dietary adaptations and metabolic compensation. In more advanced cases pharmacological treatment should be undertaken. When selecting the drug for a diabetic person one has to balance between positive and adverse actions. The drugs of the first choice are the ACE inhibitors, drugs blocking the slow calcium channel and alpha 1-adrenergic receptors, because they do not influence negatively the carbohydrate and lipid metabolism. On contrary, prazosin and ACE inhibitors increase the tissue sensitivity to insulin. The latter group decrease also intraglomerular pressure and albuminuria. As a routine the treatment begins with small, testing dose of a single hypotensive drug. The dosage may be increased slowly up to the average dose level. If this manipulation does not permit normalization of blood pressure one may combine 2 or 3 hypotensive drugs. Selection of the drug and of its dose rely also on the type and intensity of late diabetic complications--at first nephropathy and autonomic neuropathy.

[Relative effectiveness of tolbutamide, chlorpropamide and gliclazide]

In clinical practice of hypoglycemic therapy of diabetes mellitus the problem of the optimal selection of oral hypoglycemic agent, corresponding to the individual patterns of regulatory and metabolic disturbances is of primary importance. The individual, pathophysiological basis should be met as much as possible by the pharmacodynamic properties of the selected, hypoglycemic drug. For this reason group of 23 diabetics type II underwent a prolonged, open trial of controlled pharmacotherapy with 4 sulphonylurea derivatives. Pertinent clinical and metabolic parameters were assessed before, during and after planned periods of therapy with Tolbutamide or Chlorpropamide to Gliclazide and Gliclazide to Glibenclamide. In the same time the levels of serum insulin fasting and after breakfast were determined. Also the comparative efficacy of the exchange of the drug in a subgroup of diabetics with fasting glycemia below and above 160 mg% was assessed. It was shown, that the change of Tolbutamide or Chlorpropamide to Gliclazide or Glibenclamide improved the therapeutical effectiveness in general. The individual responses to such a change were however individually differentiated. The change of Tolbutamide or Chlorpropamide to Gliclazide increased the therapeutical efficacy only in these patients, in whom such a change was associated with an increase of prandial, reactive serum insulin level (IRI). In practice they were patients with the fasting glycemia lower than 160 mg%. In patients with fasting glycemia higher than 160 mg% the change of oral compounds under study was not connected with an increase of prandial serum insulin. The metabolic parameters have not improved either. Perhaps they were patients with diabetes mellitus type II, who should be primarily qualified to insulin.

[Multiple insulin injections with the help of a subcutaneous catheter or metered syringe (Pen)]

Multiple, daily injections of insulin in intensified insulin therapy of diabetes mellitus has many important advantages. From the technical point of view however it requires new instruments, which could further limit the trauma of injection and facilitate the necessary manipulations. For these reasons a combination of typical insulin syringe (Novo-Noraisk Pen) and a special subcutaneous insulin catheter (Vigo-Spectramed Insuflon) was examined in a systematic way. Insuflon was inserted for 7 days. Insulin injection was made with a syringe through the head of the Insuflon. The needle of a syringe easily penetrated the membrane inside the Insuflon 4 times daily for 7 days without any damage. The acceptance of this method was high. It increased the compliance in general. The parameters of diabetes mellitus control changed positively. No side-effects of such procedure were noted.