Multifunctional mats by antimicrobial nanoparticles decoration for bioinspired smart wound dressing solutions

Developing advanced materials for wound dressings is a very challenging, yet unaddressed task. These systems are supposed to act as temporary skin substitutes, performing multiple functions, including fluid absorption and antimicrobial action, supporting cell proliferation and migration in order to promote the skin regeneration process. Following a global bioinspired approach, in this study, we developed a multifunctional textile for wound dressing applications. Biodegradable polyhydroxybutyrate/poly-3-caprolactone (PHB/PCL) mats were fabricated by electrospinning to mimic the extracellular matrix (ECM), thus providing structural and biochemical support to tissue regeneration. Furthermore, inspired by nature's strategy which exploits melanin as an effective weapon against pathogens infection, PHB/PCL mats were modified with hybrid Melanin-TiO₂ nanostructures. These were combined to PHB/PCL mats following two different strategies: in-situ incorporation during electrospinning process, alternately ex-post coating by electrospraying onto obtained mats. All samples revealed huge water uptake and poor cytotoxicity towards HaCat eukaryotic cells. Melanin-TiO₂ coating conferred PHB/PCL mats significant antimicrobial activity towards both Gram(+) and Gram(-) strains, marked hydrophilic properties as well as bioactivity which is expected to promote materials-cells interaction. This study is going to provide a novel paradigm for the design of active wound dressings for regenerative medicine.

Fluorescent (rhodamine), folate decorated and doxorubicin charged, PEGylated nanoparticles synthesis

PEGylated silica nanoparticles, giving very stable aqueous sols, were successfully functionalised with rhodamine, one of the more stable fluorophore; they were also decorated with the targeting agent folic acid (FA) and charged with the well known drug doxorubicin. Rhodamine functionalization required a modification of the synthesis route of the nanoparticles (NP). Functionalization with FA required activation with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride. Folate decorated NP were easily charged with doxorubicin. The experimental results proved the successfulness of the functionalization. The bond to the NP does not reduce the therapeutic efficacy of the drug. The calculated encapsulation efficiency (32 %) was only a little lower than the value (47 %) reported for the very popular PEGylated PLGA NP.

Kidney and Sports

Several renal function modifications can be related to sports activity, as pre-existing renal dysfunction can influence the assessment of sports practice capability. The multiplicity of aetiologies requires an accurate diagnosis to correctly define the treatment approach and feasible activities. Previous nephrectomy or chronic renal failure are conditions that complicate the sport exercise fitness assessment and every patient should be assessed individually by a multidisciplinary medical team.

[Kidney and sports]

Several renal function modifications can be related to sports activity, as pre-existing renal dysfunction can influence the assessment of sports practice capability. The multiplicity of aetiologies requires an accurate diagnosis to correctly define the treatment approach and feasible activities. Previous nephrectomy or chronic renal failure are conditions that complicate the sport exercise fitness assessment and every patient should be assessed individually by a multidisciplinary medical team.

Iron, zinc and aluminium ferritin content of hemodialysis hyperferritinemic patients: comparison with other hyperferritinemic clinical conditions and normoferritinemic blood donors

The present study describes the specific content of ferritin iron, zinc and aluminium in four different groups: 1) hemodialysis hyperferritinemic patients; 2) septic patients; 3) iron overloaded patients with hematologic diseases; and 4) blood donors. In all four groups high levels of aluminium and zinc were found in addition to those of iron. However, the sum of the ferritin ions of the control group is significantly higher than that of the other three groups. Furthermore, while ferritin of hemodialysis patients has the same molecular ratio of metal ions as control group (high Al content vs. Fe and Zn), a lower Al/Fe ratio is found both in septic and hematological patients. The results of the present paper might help to explain the high percentage of hyperferritinemia found in hemodialysis patients also in presence of low transferrin saturation and in absence of inflammatory markers. Moreover, the high content of ions other than iron in the ferritin core leads us to believe that ferritin is not only an iron storage protein but rather a regulator of redox active ions.

Sphingosine 1-phosphate induces differentiation of adipose tissue-derived mesenchymal stem cells towards smooth muscle cells

Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid which regulates multiple biological parameters in a number of cell types, including stem cells. Here we report, for the first time, that S1P dose-dependently stimulates differentiation of adipose tissue-derived mesenchymal stem cells (ASMC) towards smooth muscle cells. Indeed, S1P not only induced the expression of smooth muscle cell-specific proteins such as alpha-smooth muscle actin (alpha SMA) and transgelin, but also profoundly affected ASMC morphology by enhancing cytoskeletal F-actin assembly, which incorporated alpha SMA. More importantly, S1P challenge was responsible for the functional appearance of Ca(2+) currents, characteristic of differentiated excitable cells such as smooth muscle cells. By employing various agonists and antagonists to inhibit S1P receptor subtypes, S1P(2) turned out to be critical for the pro-differentiating effect of S1P, while S1P(3) appeared to play a secondary role. This study individuates an important role of S1P in AMSC which can be exploited to favour vascular regeneration.

[Malnutrition in patients on chronic hemodialysis: prevalence, pathogenesis, and treatment]

Malnutrition is common in patients on hemodialysis and is a strong predicor of morbidity and mortality. Much progress has been made in recent years in identifying the causes and pathogenesis of malnutrition in hemodialysis patients as well as in recognizing the link between malnutrition and morbidity and mortality. Nevertheless, there is no consensus concerning its management. Conventional interventions such as nutritional counseling, oral nutritional supplements and intradialytic parenteral nutrition and novel preventive and therapeutic strategies such as appetite stimulants, growth hormone, androgenic anabolic steroids, and antiinflammatory drugs have been tested with contradictory and inconclusive results. Malnutrition still remains an important challenge for the nephrologist in the third millennium.

Effect of the solution flow rate on thein vitro bioactivity of 2.5CaO·2SiO2 glass

A comparative study of in vitro bioactivity of 2.5CaO x 2SiO(2) glass has been carried out by soaking it in a simulated body fluid, with continuously and periodic exchange of this solution (dynamic and differential protocols). Dynamic assays were carried out at different solution flow rates, 3 mL/h, 6 mL/h, 12 mL/h, to study the influence of flow rate on glass reactivity. Glass surface was studied by Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive spectroscopy so as to compare the behavior in the two procedures, revealing that in both cases an apatite layer is formed on the glass surface, although there are differences on deposition rate and morphology, which are also influenced by the solution flow rate.

Anorexia in hemodialysis patients: An update

Anorexia, defined as the loss of the desire to eat, is relatively common in hemodialysis (HD) patients, occurring in one-third of cases. The pathogenesis is essentially unknown. It has been proposed that uremic toxins as middle molecules, inflammation, altered amino-acid pattern, leptin, ghrelin, and neuropeptide Y are involved. Anorexia reduces oral energy and protein intakes, thus contributing to the development of malnutrition and cachexia. Unquestionably, it contributes to poor quality of life. The clinical relevance of anorexia as an independent prognostic factor in HD patients is a matter of debated issue. The treatment of this debilitating condition is based on a therapeutic strategy which may include daily dialysis sessions and nutritional counseling. Normalization of plasma branched-chain amino acids through branched-chain amino acids supplementation may decrease anorexia and improve energy and protein intake. The role of megestrol acetate as appetite stimulant needs to be validated through adequate randomized trials. Subcutaneous ghrelin administration and melanocortin-receptor antagonists appear promising therapeutic interventions.

Small bowel intussusception: what is the role of laparoscopy?

Small bowel intussusception in adults is a rare surgical disease which almost always occurs as a complication of either benign or malignant lesion of the bowel that is working as a leading point. In adults, the surgical approach consists of the resection of the bowel involved to ensure the excision of the lesion below. The authors report a case of ileocecal intussusception occurred in a young woman, 35 years old, observed for abdominal pain and signs of small bowel occlusion. She underwent surgical resection of the ileocecal segment with laparoscopic approach. The authors discuss the feasibility of the laparoscopic approach in this rare surgical disease and its benefits in terms of patient's postoperative comfort and outcome.

Swelling properties and bioactivity of silica gel/pHEMA nanocomposites

A novel hydrogel based on 2-hydroxyethyl- methacrilate and SiO(2) nanoparticles was prepared. The filler was added at a concentration of 30% w/w of silica nanoparticles to the mass of polymer. The composite material was characterised as far as concerns swelling behaviour in comparison to pHEMA. Swelling ratio of modified pHEMA was higher. Bioactivity of both SiO(2) nanoparticles and the modified hydrogel was evaluated by soaking samples into a simulated body fluid (SBF). FT-IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive system (EDS) results suggest silica nanoparticles keep bioactive in the polymer. SiO(2) filler in a p(HEMA) matrix makes the composite bioactive. Therefore, these composites can be used to make bioactive scaffold for bone engineering.

Poly(2-hydroxyethyl methacrylate) biomimetic coating to improve osseointegration of a PMMA/HA/glass composite implant: in vivo mechanical and histomorphometric assessments

Bone implants must simultaneously satisfy many requirements, even though the surface properties remain a crucial aspect in osseointegration success. Since a single material with a uniform structure cannot satisfy all of these requirements, composite materials specifically designed for orthopedic or dental implant application should be envisaged. Two poly(methylmethacrylate)/hydroxyapatite composites reinforced by E-glass fibres, uncoated (PMMA/HA/Glass) and poly(2-hydroxyethyl methacrylate) (PMMA/HA/Glass+pHEMA) coated by the biomimetic method, were mechanically (push-out test) and histomorphometrically (Affinity Index, AI) investigated in an in vivo rabbit model. Cylindrical implants (diameter 2 mm x 5 mm length) were inserted into rabbit femoral cortical (mid-diaphysis) and cancellous (distal epiphysis) bone, under general anesthesia. The highest values of push-out force and ultimate shear strength were observed for the PMMA/HA/Glass at 12 weeks, which significantly (p < 0.001) differed from those of PMMA/HA/Glass+pHEMA at the same experimental time and from those of PMMA/HA/Glass at 4 weeks. At both experimental times, significantly (p < 0.0005) lower values of AI were observed in the PMMA/HA/Glass+pHEMA versus PMMA/HA/Glass (distal femoral epiphysis: 4 weeks = 33%; 12 weeks = 19%; femoral diaphysis: 4 weeks = 15%; 12 weeks = 11%). The good mechanical and histomorphometric results obtained with PMMA/HA/Glass should be followed by further evaluation of bone remodeling processes and mechanical strength around loaded PMMA/HA/Glass implants at longer experimental times. Finally, the biomimetic method applied to pHEMA needs to be further investigated in order to improve the positive effect of SBF on pHEMA and to enhance the coating adhesion.

Hydroxyapatite coating of titanium by biomimetic method

The biomimetic method was used in order to deposit, on titanium substrates, an hydroxyapatite (HA) coating. The bioactive HA layer was obtained by using, in the first stage of the process, a glass having the composition 2.5CaO.2SiO(2) different from the one proposed for the application of the biomimetic method. This glass can be obtained via sol-gel, a method that allows one to obtain, easily, very pure products. The growth of HA crystals was confirmed by Fourier transform infrared, SEM, EDS and X-ray photoelectron spectroscopy (XPS) results. The experimental results suggest that, as reported in the literature for other supports, the silicate ions released from the glass in the first stage bind themselves to the titanium support. In particular, from XPS analysis it is evident that the titanium substrate is well covered by a calcium phosphate layer of the type of HA.

Effect of the substitution of M2O3 (M = La, Y, In, Ga, Al) for CaO on the bioactivity of 2.5CaO x 2SiO2 glass

Glasses were prepared whose compositions are defined by the following general formula: (2.5 - x)CaO x x/3M2O3 x 2SiO2 (0 < or = x < or = 0.6) (M = Ga, Al, In). Their bioactivity was studied "in vitro" by soaking the glasses in a simulated body fluid (SBF). The consequent formation of calcium phosphate layer was studied by means of electron microscopy (EM) equipped with an energy-dispersive system (EDS) for elemental analysis and Infrared (IR) spectroscopy. The results are compared to the literature relative to the substitution of La2O3 and Y2O3 for CaO. It is observed that, in general, the substitution of M2O3 for CaO in the binary CaO-SiO2 glass composition progressively reduces the ability to form a calcium phosphate layer on the surfaces exposed to simulated body fluid (SBF). The composition limit can be related to the ionic field strength of the substituting cation and to the CaO content of the base glass. According to the mechanism reported in the literature a silica gel-like surface layer initially forms on the surfaces exposed to SBF. The observed results can be attributed to the effect of the substitution of M2O3 for CaO on the acidic properties of the silanolic groups.

Improvement of swelling properties of poly(2-hydroxyethyl methacrylate) hydrogel by means of biomimetic method

Poly(2-hydroxyethyl methacrylates) (PHEMAs) structurally modified by means of polymer blends and random copolymers are intensively studied in order to improve mechanical properties. It was recently shown that a hydroxyapatite coating, which should improve the bonding of this biomaterial to the bone, can be obtained by means of the biomimetic method. When PHEMA is submitted to the biomimetic method, its swelling ratio is improved. This can be ascribed to the deposition of a silicatic layer, which improves the hydrophilicity, on the surface of the internal pores during the first stage of the method. This appears to be a valuable result for producing modified PHEMAs with improved mechanical properties and good swelling. The experimental results indicate the following: stronger interactions with the water molecules are set up, an induction period is observed that is linked to the rate of the reactions occurring at the surface of the glass and the establishment of a convenient concentration of the silicate ions at the external surface of the polymer, and the diffusion of simulated body fluid into the pores is the limiting stage of the process.

Incidence of incisional hernia following emergency abdominal surgery

BACKGROUND

A retrospective study was conducted to determine incidence and predisposing factors of incisional hernia after an emergency midline laparotomy.

PATIENTS AND METHODS

The study population consisted in 197 patients of whom 138 were followed-up for 2 years after surgery.

RESULTS

An incisional hernia developed in 25 (18.1%) patients at a mean follow-up of 11.2 months. Multivariate analysis showed the importance of age (> 60 years, p < 0.004), obesity (p < 0.008) and occurrence of post-operative wound infection (p < 0.00001) for the development of an incisional hernia. Univariate analysis showed that intestinal occlusion (p < 0.02), peritonitis (p < 0.006), upper abdominal access (p < 0.04) and post-operative wound infection (p < 0.003) in older patients and obesity (p < 0.003) and the presence of a neoplasm (p < 0.006) in younger patients, played a significant role. The comparison between young and old patients showed that upper abdominal access (p < 0.007), interrupted and layered wound closure (p < 0.02 and p < 0.01, respectively) and contamination of the operative field (p < 0.004) played a statistically significant role in older patients.

CONCLUSIONS

The rate of incisional hernia after an emergency midline laparotomy is higher than after elective procedures. However, it could be reduced with proper attention to the suture technique, i.e. mass and continuous suture, better preparation of the operative field and scrupulous sterility throughout the procedure in order to decrease the incidence of post-operative wound infection.

Antioxidant status and dialysis: plasma and saliva antioxidant activity in patients with fluctuating urate levels

The present study is concerned with the influence of processes occurring during dialysis on the antioxidant capacity of plasma and saliva. The biological fluids were also tested for uric acid and total protein content. Before hemodialysis, plasma antioxidant status of hemodialyzed patients appears slightly higher than the corresponding status in normal subjects; after hemodialysis it is found unchanged. The result can be explained by a balance between a reduction in uric acid plasma content, due to the dialytic procedure, and an increase in protein content, possibly due to a dialysis-related hemoconcentration. Moreover, pre-dialysis total antioxidant capacity of whole saliva samples is higher than in healthy individuals and drastically decreases towards normal values following dialytic procedure. Our data indicate a certain concentration of the uric acid in the saliva of hemodialyzed patients and evidence that both total protein concentration and uric acid level show a good correlation with saliva total antioxidant capacity, suggesting that proteins are major antioxidants of this fluid. Further observations are needed to assess whether this improved saliva antioxidant ability has any consequence on the periodontal conditions of hemodialyzed subjects.

[Exposure to wood dust in a group of carpentry craftsmen in secondary wood processing]

In order to evaluate the risk connected with wood dust exposure in millwork on a group of 13 craft industries, 74 area dust samplings and 74 personal dust samplings were made. In personal samplings both the total portion and the respirable fraction were calculated. Area samplings showed dust levels (average, standard deviation, fiducial limit, FLS95%) under ACGIH TLV-TWA for soft wood dust: TLV-TWA for hard wood was basically reached, and OTL levels gave evidence for high risk of exceeding TLV-TWA in the medium-long term. The exposure levels by personal samplings (average, standard deviation, fiducial limit, FLS95%) were clearly over TLV-TWA, both for hard woods and, although less clear, for soft woods. OTL levels gave evidence for a frankly unacceptable exposure condition in the medium-long term. Differences between average levels of total dust exposure (2.5 mg/m3) and respirable portion (2.3 mg/m3) were not statistically significant (p > 0.05) as well as the differences among the 4 groups of companies with homogeneous product activity (p > 0.05). In consideration of toxicological peculiarity of wood dust and carcinogenicity of wood manufacture as exposure circumstances classified in group 1 by IARC, the results show the need for prevention measures to reduce workers' exposure risk, by means of environmental improvement and better work organization, technological structures, individual attitudes and personal protection.

Influence of blunt needles on surgical glove perforation and safety for the surgeon

BACKGROUND

Round-tipped blunt needle (BN) may decrease the risk of needlestick injuries and hand contamination. We prospectively determined the incidence of glove perforations in emergency abdominal procedures and the efficacy of BN in increasing the safety for surgeons.

METHODS

Two hundred patients were randomized to undergo closure of the abdominal fascia using sharp needle (SN) or BN. Gloves were tested at the end of the procedure.

RESULTS

Surgeons had 14 needlestick injuries and 76 perforations recorded in 69 pair of gloves. Sharp needles were responsible for all injuries and 58 (76%) perforations (P < 0.00004 and P < 0.00001, respectively). This difference was still higher when considering the perforations related to the abdominal fascia closure (BN 7% versus SN 50%; P < 0.0006).

CONCLUSION

The risk of glove perforation is sevenfold greater if SN are used. Blunt needles reduce sharp injuries and improve safety for surgeons.

Paroxystic hypertension in a long-term hemodialyzed patient. Successful adrenalectomy for a dopamine-producing pheochromocytoma

Pheochromocytoma (Pheo) is an uncommon neoplasm producing blood pressure troubles and it may be undiagnosed in chronic dialyzed patients in whom hypertension is a common finding. The symptoms in Pheo syndrome depends on the prevalent catecholamine released, the most common being epinephrine (E) and norepinephrine (NE). Recently, a particular clinical picture has been described for dopamine (DA)-producing Pheos, in whom a normo-hypotensive status is more often observed. The authors report a case of mainly dopamine-producing Pheo in a long-term dialyzed patient, successfully treated with adrenalectomy. The main steps in diagnosis and preoperative management are described and debated also in view of the particular background produced by the end-stage renal failure. The common imaging techniques adopted for adrenal medullary neoplasms (US, CT, MIBG scintiscan) confirmed to be decisive for diagnosis; HPLC assay of plasma catecholamines is the only biochemical test available in these patients although its significance is questionable due to the poor knowledge of catecholamine metabolism in chronic renal failure. The clinical findings observed in this case seem in disagreement with those already reported in DA producing Pheos. Pheo in hemodialyzed patients is a rare event and it may be hidden by other more common causes of hypertension. However, more awareness from the medical staff allows to diagnose the neoplasm correctly by the currently available methods and to plan a safe surgical therapy also in high-risk patients.

[Duplication of the gastrointestinal tract: a report of a rare case of mediastinal cyst]

An unusual case of alimentary tract duplication located in the left anterior mediastinum and observed in a 37-year-old woman is reported. Resection of the lesion through a left thoracotomy approach was resolutive and followed by an excellent long term outcome. Etiology, diagnosis and therapeutic problems as well as differential diagnosis with benign and malignant chest lesions of adult population are briefly discussed.

[Surgical day hospital: technical possibilities and organizational model]

The Authors propose an organizational model for a surgical day hospital program, which is being used for a pilot day surgery unit in the I Department of Surgery of the Rome University "La Sapienza". The program requires little capital investment, as it is closely linked, geographically and administratively, to the main surgical unit, and uses the present staff, facilities and support services. The model is based on a computerized LAN (Local Area Network), providing fast recording, scheduling, management and trannsfer of medical data for each patient. The present situation is reported in detail. Data from the authors' outpatient department for 1988, have been recorded and elaborated. The results show a low use of surgical day care, limited to minor surgical procedures, and with not a single operation performed under general anesthesia. The authors hope to see a growth in the use of day surgery and a more selective use of inpatient care.

Halothane does not alter Ca2+ affinity of troponin C

Troponin C has been suggested as a possible target for the negative inotropic action of volatile anesthetics. This study has examined the effect of halothane on the structure and response of isolated cardiac troponin C to Ca2+ and the response of skinned soleus and cardiac muscle fibers to Ca2+. The high-affinity Ca(2+)-binding sites of cardiac troponin C were assessed by measurement of the change in intrinsic tyrosine fluorescence and ultraviolet circular dichroism in response to Ca2+ in the presence and absence of halothane. Halothane (0.9 mM, 1.4%) did not alter the 45% enhancement in intrinsic tyrosine fluorescence that occurs with saturation of the high-affinity sites or change the Ca2+ concentration at which half-maximal enhancement occurred. The molar ellipticity in the far ultraviolet region, a measure of the secondary structure, increased to a similar extent with addition of 10(-6) M Ca2+ in the absence and presence of 1.0 mM (1.6%) halothane. The binding rate of the sulfhydryl reagent, 5,5'-dithiobis (2-nitrobenzoic acid), to troponin C in response to Ca2+ titration was used as a measure of the integrity of the low-affinity Ca(2+)-binding site in troponin C in the presence and absence of 1.0 mM (1.6%) halothane. The rate of reaction was stimulated twofold, and the half maximal effect was observed at pCa 4.8 +/- 0.2 in both control and halothane-treated samples. Halothane (5 mM; 7.8%) did not change the pCa/tension response of skinned soleus fibers; the data were fit to the Hill equation and yielded dissociation constants of 6.2 x 10(-7) M for control and halothane-treated specimens.(ABSTRACT TRUNCATED AT 250 WORDS)

Tolerance to inhaled Duovent. A long-term study

Fenoterol with ipratropium bromide (Duovent) is a recently used combination between an anticholinergic and a beta-adrenergic drug useful in obtaining a more effective bronchodilatation and/or reducing the single drug doses. It has been suggested that, as in the case of beta-agonists, its clinical efficacy may be limited by the development of tolerance. We studied the effects of inhaled Duovent in 15 asthmatic patients for 3 months, using a rigidly controlled protocol. Appropriate serial physiological measurements were made at regular intervals during the 90-day study. In all instances the day-one bronchodilator response was significant, prompt and sustained: at 1, 4, 8 and 12 weeks the response was statistically the same as on day 1. It is concluded that, when the important variables are properly controlled, no evidence of tolerance to long-term therapy with Duovent is demonstrable.

Acute controlled study of the dose-response relationship of fenoterol, ipratropium bromide and their combination

A double-blind study was carried out in a group of 9 patients with partially reversible airway obstruction, to evaluate the bronchodilator effect of gradually increased doses of fenoterol (cumulative doses: 100, 200, 400, 800 and 1,600 micrograms), ipratropium bromide (40, 80, 160, 320 and 640 micrograms) and a combination of these (100 + 40, 200 + 80 micrograms, etc.), denominated Duovent. The three treatments were carried out at random at the same time on 3 days, usually not consecutive days, whereby 1, 1, 2, 4 and 8 puffs (altogether 1, 2, 4, 8 and 16 doses) of each product were given in identical pressurized aerosols at intervals of 60 min. Respiratory (spirometry and flow-volume curve) and cardiovascular (blood pressure, heart rate) parameters were measured under basal conditions and 60 min after each administration. On average, with all three products, the bronchodilatory effect showed a linear correlation with the logarithm of the dose given. With the same number of puffs the side-effects (tremor in particular) of the combination fenoterol and ipratropium bromide or Duovent (FIB) were markedly fewer than those of fenoterol, while ipratropium bromide was very well tolerated. The three dose-response curves (parallel) show that, in respect of an increase in FEV1, 1 puff of Duovent (100 micrograms fenoterol + 40 micrograms ipratropium bromide) is approximately equal to 2 puffs of fenoterol (200 micrograms) and 4 puffs of ipratropium bromide (160 micrograms). FIB, therefore, makes it possible to maintain the same bronchodilatory effect as the full dose (400 micrograms) of fenoterol while improving the therapeutic value.

Protective effect of Duovent versus salbutamol in long-term treatment

The effect of the combination fenoterol-ipratropium bromide (Duovent) as a bronchodilator drug versus salbutamol and placebo was investigated in 20 patients with chronic obstructive lung disease in a random cross-over trial. Our study was performed not only to evaluate the bronchodilator response, but especially to quantify the possibly more prolonged action of Duovent versus salbutamol, based on registration of prevention of asthma attacks, time effects and protective activity, management and tolerance. Each patient received therapy for 3 weeks; in each week only one of the preparations: salbutamol, Duovent or placebo was used. Respiratory function tests were determined every week on the 3rd, 5th and 7th days at the same time exactly at 30 and 60 min after drug inhalation. Additionally we registered, for each patient, daily symptomatology (e.g., asthma attacks, cough, additional daily puff use, adverse reactions) by using a personal clinical diary. The results and analysis of the pulmonary tests (especially FEV1 and peak expiratory flow) confirmed the bronchodilator effect of both drugs, higher for Duovent but not sufficient to reach statistical significance. Clinical condition, regarding number, severity of asthma crises and additional puff use, showed a significant statistical variation for each symptom either as regards advantage of Duovent and salbutamol versus placebo, or advantage of Duovent versus salbutamol. Therefore, the results of this trial reveal an excellent bronchodilator effect of both drugs and confirm a higher clinical efficacy of Duovent if used in long-term treatment, with good tolerability.

Glucocorticoid inhibitory action on the response to PHA of residual circulatory lymphocytes in renal transplant patients following immunosuppressive therapy

The inhibitory effect of glucocorticoids on the in vitro response to phytohaemagglutinin of the residual circulating T lymphocytes in renal transplant patients during maintenance immunosuppressive therapy with glucocorticosteroids and azathioprine has been investigated. As in normal subjects, the steroid-induced inhibition of transplanted patients' lymphocyte response was inversely correlated with the mitogen concentration used. On the other hand, the response of the various lymphocyte preparations from transplanted patients appeared less inhibited by steroids than the corresponding preparations from normal subjects. The addition to the culture of the adherent cell product interleukin 1 was effective in removing to a similar extent the steroid inhibitory effect on lymphocytes from normal and transplanted subjects. Thus, the lesser inhibitory effect of glucocorticoids on transplanted patient lymphocytes could be explained by the higher percentages of monocytes present in all peripheral blood mononuclear cell preparations. These results suggest that during immunosuppressive therapy with glucocorticoids and azathioprine the residual circulating lymphocytes have a responsiveness to in vitro dexamethasone suppression similar to that of normal peripheral blood lymphocytes.

Imbalances in peripheral blood T-cell subpopulations in renal transplant patients

The distribution of T-lymphocyte subpopulations bearing receptors for the Fc portion of IgG (TG) or IgM (TM) was monitored in 22 renal allograft recipients treated with immunosuppressive therapy and in 10 uraemic patients on haemodialysis. No significant difference in the distribution of T cells and T-cell subsets was found between normal controls and haemodialysed patients. In transplanted patients, however, a significant reduction of the total T-cell percentage (P less than 0.005), of TM subset percentage (P less than 0.025) and absolute number (P less than 0.005) and of TG absolute number (P less than 0.05) was observed. Considering patients with allografts functioning for more than 1 year only, the reduction in TM cells in terms of percentage (P less than 0.0005) and absolute number (P less than 0.025) was significant, while TG subset levels did not change significantly. In patients transplanted less than 1 year previous to our study, total T cells and T-cell subsets were reduced significantly only as absolute numbers. During the 1st year we observed several increments of TM values towards normal levels, especially in the first 2 months after transplantation. During this period, TM subset levels sharply increased at acute rejection crisis and returned to previous values with rejection reversal. Our results suggest that the TM subset plays a prominent role in the mechanisms involved in the immunological response to allografts, and therefore repeated TM cell monitoring could be useful in the follow-up of renal transplant patients.

Autoimmunity in ocular and generalised myasthenia gravis

Restricted ocular myasthenia gravis (OMG) and generalised myasthenia gravis (GMG) have been shown to differ in a number of respects. In OMG, antiacetylcholine receptor, antistriational and antinuclear antibodies were rare relative to their frequency in GMG. In contrast, antithyroid antibodies and a history of thyroid disease were much more prevalent in OMG than in GMG, OMG was not associated with the female predominance seen in GMG and appeared to be relatively common in some races rather than others. It is suggested that different pathogenetic mechanisms are responsible for these two forms of MG.

A new HLA antigen apparently not controlled by the known HLA loci

The human allogeneic serum RM3 recognizes a lymphocyte structure inherited with the HLA chromosome. Population studies show several positive associations with antigens of the HLA-A and HLA-B series. Negative association have been found with antigens of the HLA-C series. Moreover the distribution of the RM3 factor is in Hardy-Weinberg equilibrium with that of the HLA-C alleles. However, serological investigations (namely the 'lysostrip' technique) bring evidence that RM3 serum does not appear to contain antibodies directed against any of the antigens of the HLA-A, B and C series. The study of a segregant family, showing a crossing over between the HLA-A and HLA-B loci, shows that the RM3 factor segregates on the side of the HLA-A locus. In conclusion, within the limits of the serological approach used, the present study presents evidence of a new serologically defined HLA locus, different from those so far described.