Effects of saline nebulization on SARS-CoV-2 RNA spreading and exhaled bio-aerosol particles in COVID-19 patients

BACKGROUND

Nebulized therapy is the mainstay for treating obstructive airway diseases, but there is heightened concern about the potential risk for SARS-CoV-2 transmission during nebulization in COVID-19 patients.

AIM

To investigate the effects of 0.9% saline nebulization on SARS-CoV-2 RNA spreading in 11 COVID-19 patients (five females, mean age 62.45 ± 9.31 years); also to ascertain whether saline nebulization changed the number of exhaled bio-aerosol particles in six out of the 11 patients.

METHODS

Air samples were collected using suction pumps equipped with 0.45 μm PTFE filters and positioned around the patient's bed. Exhaled particles were quantified by using an optical particle counter.

FINDINGS

At baseline (i.e. before nebulization) SARS-CoV-2 was detected more frequently in the pumps close to the patient than in those far away. After saline nebulization, the detection of SARS-CoV-2 in the pumps close to the patient was comparable to that observed at baseline. In the pumps far from the patient, saline nebulization slightly, but not significantly, increased SARS-CoV-2 RNA detection compared to baseline. Overall, no significant changes in the SARS-CoV-2 RNA detection were observed after saline nebulization. At baseline, exhaled particle emission varied among patients, with two of them showing higher emission of particles than the remaining patients. Saline nebulization induced a marked decrease in exhaled particles in the two patients who displayed high emission at baseline, whereas no changes were observed in the remaining patients. Saline nebulization did not significantly change SARS-CoV-2 RNA spreading.

CONCLUSION

Saline nebulization does not significantly increase SARS-CoV-2 spreading.

Prognostic Value of the Kiel Classification of Malignant Non-hodgkin's Lymphomas

The aim of the present research was to evaluate the prognostic value of the Kiel classification of malignant non-Hodgkin's lymphomas. For this purpose a series of 100 consecutive, previously untreated adults with advanced malignant non-Hodgkin's lymphomas was analyzed. The median age of the patients was 54 years; 61 patients were males. Although the number of the various groups considered was limited, a statistically significant difference (p < 0.001) was found in the median survival of patients with lymphomas of low-grade malignancy (lymphocytic, lymphoplasmacytoid, centrocytic, centroblastic-centrocytic lymphoma) and lymphomas of high-grade malignancy (centroblastic, lymphoblastic, immunoblastic lymphoma). A difference in survival (p < 0.001) was also observed among the patients with lymphocytic lymphoma and those with centroblastic-centrocytic lymphoma, whereas no significant difference in survival was found between the histological subtypes of high-grade malignant lymphomas. Our observations support the opinion that the Kiel classification is useful in clinical practice to distinguish the histological types with a better prognosis from those with a worse one; in addition this classification appears to be of conceptual value.

Anti-fibronectin aptamers improve the colonization of chitosan films modified with D-(+) Raffinose by murine osteoblastic cells

The aim of the present study was to investigate how the enrichment of chitosan films with anti-fibronectin aptamers could enhance scaffold colonization by osteoblasts, by improving their adhesion and accelerating their proliferation. Chitosan discs were enriched with excess of anti-fibronectin aptamer. Aptamer adsorption on chitosan was monitored by measuring aptamer concentration in the supernatant by spectrophotometry, as well as its release, while functionalization was confirmed by labelling aptamers with a DNA intercalating dye. Chitosan samples were then characterized morphologically with atomic force microscopy and physically with contact angle measurement. Chitosan enrichment with fibronectin was then investigated by immunofluorescence and Bradford assay. 2% chitosan discs were then enriched with increasing doses of aptamers and used as culture substrates for MC3T3-E1 cells. Cell growth was monitored by optical microscopy, while cell viability and metabolic activity were assessed by chemiluminescence and by Resazurin Sodium Salt assay. Cell morphology was investigated by cytofluorescence and by scanning electron microscopy. Chitosan films efficiently bound and retained aptamers. Aptamers did not affect the amount of adsorbed fibronectin, but affected osteoblasts behavior. Cell growth was proportional to the amount of aptamer used for the functionalization, as well as aptamers influenced cell morphology and their adhesion to the substrate. Our results demonstrate that the enrichment of chitosan films with aptamers could selectively improve osteoblasts behavior. Furthermore, our results support further investigation of this type of functionalization as a suitable modification to ameliorate the biocompatibility of biomaterial for hard tissue engineering applications.

Systematic review of resection of primary midgut carcinoid tumour in patients with unresectable liver metastases

BACKGROUND

Surgery for small intestinal neuroendocrine tumours (SI-NETs) is limited by metastatic disease in most patients. However, resection of the primary lesion alone has been advocated in patients with unresectable liver metastases. The present systematic review investigated the value of surgical resection of the primary lesion in patients with unresectable metastatic disease.

METHODS

MEDLINE was searched for studies reporting the outcome of patients with SI-NETs and unresectable liver metastases where there was an explicit comparison between resection of the primary lesion alone and no resection. The primary outcome was overall survival. Secondary outcomes were progression-free survival, treatment-related mortality and relief of symptoms.

RESULTS

Meta-analysis was not possible, but six studies were analysed qualitatively to highlight useful information. Possible confounders in these studies were the inclusion of patients with other primary tumour sites, unknown primary tumour or non-metastatic disease. Bearing in mind these limitations, there was a clear trend towards longer survival in patients who underwent surgical resection in all studies; their median overall survival ranged from 75 to 139 months compared with 50-88 months in patients who did not have resection. The difference between the two groups was statistically significant in three studies. Data on symptomatic improvement were scarce and did not suggest a clear benefit of surgery. Surgery-related mortality seemed low.

CONCLUSION

Available data suggest a possible benefit of resection of the primary lesion in patients with unresectable liver metastases, but the studies have several limitations and the results should therefore be considered with caution.

Ethyl-paraben and nicotinamide mixtures: apparent solubility, thermal behavior and X-ray structure of the 1:1 co-crystal

This work aims at investigating the nicotinamide (NA)-ethyl-paraben (EP) binary system both in solution and in the solid state. In particular, the apparent EP solubility in water was studied in the presence of different NA concentrations (between 0.28 and 1.64 M). It was found that the apparent EP solubility increase (nearly twofold) observed at the highest NA concentration tested can be ascribed to a change in the polarity of the solvent mixture, rather than to a direct effect of NA on EP. The effect of fusion and re-crystallization from water or ethanol solutions on EP and NA mixtures was investigated by means of differential scanning calorimetry, elemental analysis and X-ray diffraction both on powder and single crystal. It was discovered that EP and NA form a co-crystal having a 1:1 molar composition that can be easily crystallized from ethanol. Single crystal X-ray analysis of this species revealed that the NA and EP molecules form corrugated layers within which the two components are intimately associated by a dense network of hydrogen bonds. In the presence of an excess NA in solution, the EP-NA co-crystal has lower water solubility with respect to both the single co-crystal formers and precipitates in aqueous solutions at ambient temperature.

Novel platforms for oral drug delivery

The aim of this review is to provide the reader general and inspiring prospects on recent and promising fields of innovation in oral drug delivery. Nowadays, inventive drug delivery systems vary from geometrically modified and modular matrices, more close to "classic" pharmaceutical manufacturing processes, to futuristic bio micro-electro-mechanical systems (bioMEMS), based on manufacturing techniques borrowed from electronics and other fields. In these technologies new materials and creative solutions are essential designing intelligent drug delivery systems able to release the required drug at the proper body location with the correct release rate. In particular, oral drug delivery systems of the future are expected to have a significant impact on the treatment of diseases, such as AIDS, cancer, malaria, diabetes requiring complex and multi-drug therapies, as well as on the life of patients, whose age and/or health status make necessary a multiple pharmacological approach.

Primary tumour resection in metastatic nonfunctioning pancreatic endocrine carcinomas

BACKGROUND

The role of debulking surgery in metastatic nonfunctioning pancreatic endocrine carcinomas (M-NF-PECs) with resectable primary tumour and unresectable liver metastases is debated.

AIM

Aim of the study is to evaluate whether the resection of the primary tumour in metastatic nonfunctioning pancreatic endocrine carcinoma improves survival.

PATIENTS AND METHODS

Fifty-one metastatic nonfunctioning pancreatic endocrine carcinoma patients with unresectable liver metastases were enrolled from 1990 to 2004 at the time of diagnosis. Nineteen patients underwent complete resection of the primary tumour whilst 32 were judged unresectable. All cases were classified according to the WHO 2000 classification. All clinico-pathological parameters, including grade of differentiation and the Ki-67 proliferation index were considered in univariate and multivariate models.

RESULTS

Of the 19 resected patients, 14 (73.7%) underwent left-pancreatectomy and 5 (26.3%) pancreaticoduodenectomy. In the unresected group of 32 patients, 9 (28.1%) underwent surgical biliary and/or gastric by-pass. There was no postoperative mortality and the median survival was 54.3 months (95% CI: 25.7-82.9). No difference in survival was observed between the two groups [resected: median 54.3 months (95% CI: 25-83.6), unresected: median 39.5 months (95% CI: 5.4-73.6); p=0.74]. Upon multivariate analysis poor differentiation (HR 3.01; 95% CI 1.08-8.4; p=0.035) and a Ki-67 index > or = 10% (HR 4.4; 95% CI 1.2-16.1; p=0.023) were significant predictors of survival.

CONCLUSIONS

Resection of the primary pancreatic tumour in metastatic nonfunctioning pancreatic endocrine carcinoma patients with unresectable liver metastases does not significantly improve survival. Resection can be considered as symptomatic palliative therapy in patients with well-differentiated endocrine carcinomas and a proliferative index lower than 10%.

Supercritical extraction of carotenoids from Rosa canina L. hips and their formulation with beta-cyclodextrin

The purpose of this research was to preliminary assess the suitability of a new method for the preparation of a solid formulation in form of powder composed by beta-cyclodextrin and the supercritical extract of Rosa canina hips. The method implies the extraction of carotenoids, in particular beta-carotene, from freeze dried fruits of R. canina with supercritical CO2 at 70 degrees C and 300 bar, in the presence of varying quantity of ethanol as entrainer. The obtained supercritical solution is then expanded at ambient conditions into an aqueous solution of beta-cyclodextrin to favour the interaction between beta-cyclodextrin and the lipophilic components of the extract. beta-carotene solubility (mole fraction) in supercritical CO2 or in supercritical CO2/ethanol mixtures were in the order of 1 10(-7). The beta-carotene extracted from R. canina fruits (nearly 10 microg/g of dry matrix), interacts almost quantitatively with beta-cyclodextrin affording a solid phase, which presents a low apparent solubility in water. Finally the interaction with beta-cyclodextrin results in a higher concentration of the beta-carotene trans- form relative to the cis- form in the extracted product when collected in an aqueous solution of beta-cyclodextrin with respect to the extract in n-hexane.

Prognostic factors at diagnosis and value of WHO classification in a mono-institutional series of 180 non-functioning pancreatic endocrine tumours

BACKGROUND

Non-functioning pancreatic endocrine tumours (NF-PETs) are an aggressive gastroenteropancreatic neoplasm. The present study assessed survival, value of World Health Organisation (WHO) classification and prognostic utility of clinicopathological parameters at diagnosis.

PATIENTS AND METHODS

From 1990 to 2004, 180 patients with NF-PETs were entered in a prospective database, and predictors of prognosis were tested in uni- and multivariate models.

RESULTS

There were 25 (14%) benign lesions, 38 (21%) neoplasms of uncertain behaviour, 100 well-differentiated carcinomas (56%) and 17 poorly differentiated carcinomas (9%). Radical resection was possible in 93 cases (51.6%). Overall 5-, 10- and 15-year survival rates were 67%, 49.3% and 32.8%, respectively, and were significantly higher in radically resected patients (93%, 80.8% and 65.2%, respectively; P < 0.00001). By multivariate analysis, poor differentiation [hazard ratio (HR) 7.3; P = 0.0001], nodal metastases (HR 3.05; P = 0.02), liver metastases (HR 3.29; P = 0.003), K(i)-67 >5% (HR 2.5; P = 0.012) and weight loss (HR 3.06; P = 0.001) were significantly associated with mortality.

CONCLUSION

This study confirms the good long-term survival of patients with NF-PETs and the prognostic value of WHO classification, liver metastases, poor differentiation, Ki-67, nodal metastases and weight loss. These latter two parameters have a prognostic value similar to that of liver metastases and Ki-67.

A case of intraductal papillary mucinous tumour following recurrent attacks of pancreatitis lasting 26 years

We report an interesting case of a patient with neither family nor personal history for pancreatic diseases that was admitted to our department in 1982, at the age of 25 years. At that time, medical history, absence of alcohol abuse, and radiological imaging suggested a diagnosis of idiopathic chronic pancreatitis. The patient underwent a left-pancreatectomy, with histological confirmation of chronic pancreatitis. He was asymptomatic until 1988, when episodes of pain arose, requiring a pancreatico-jejunostomy. No further problems ensued until 2004 when radiological investigation following pain-related symptoms revealed enormous dilation of the pancreatic duct. A pylorus-preserving pancreaticoduodenectomy resulting in total pancreatectomy was performed. Histological examination revealed an intraductal papillary mucinous non-invasive carcinoma. Review of the previously resected specimen revealed former misdiagnosis. This tumour usually affects an elderly population and nowadays is recognised as a possible cause of chronic obstructive pancreatitis. This report represents a slippery case of misdiagnosis and demonstrates that follow-up is always mandatory following a diagnosis of idiopathic chronic pancreatitis.

Predictive factors of efficacy of the somatostatin analogue octreotide as first line therapy for advanced pancreatic endocrine carcinoma

About 40% of nonfunctioning pancreatic endocrine carcinomas (NF-PEC) cannot be cured by surgery due to advanced stage disease. Somatostatin analogues have been proposed as first line therapy in these cases. We performed a prospective phase IV study to assess the efficacy of octreotide in advanced NF-PEC and identify factors predictive of response to therapy. Twenty-one consecutive patients with octreoscan-positive advanced-stage well-differentiated NF-PEC were treated with long-acting release octreotide 20 mg i.m. at diagnosis. The immunohistochemical expression of somatostatin receptor 2 (SSTR2) and the quantitative mRNA analysis of SSTR2 and SSTR5 were assessed in 12 tumours. The tumour proliferative fraction was assessed by immunohistochemistry for Ki-67. Eight patients (38%) had stable disease (SD) after a median follow-up of 49.5 months. Thirteen patients (62%) developed progression after a median of 18 months. Tumour progression correlated with a proliferative index>or=5% (P=0.016), weight loss (P=0.006) and absence of abdominal pain (P=0.003) at diagnosis. Other clinical (age, gender and primary tumour resection) or pathological parameters (site, size and liver metastasis) lacked significant correlation with tumour progression. No difference in the amount of SSTR2 mRNA and protein or SSTR5 mRNA was found between tumours that were stable (n=5) and seven tumours that progressed (n=7). Treatment with long-acting release octreotide was associated with stabilization of disease and a good quality of life in 38% of patients. A Ki-67 index>or=5% and/or the presence of weight loss may justify more aggressive therapy without waiting for radiologically proven progression of disease.

Development of a disease-specific Quality of Life questionnaire module for patients with gastrointestinal neuroendocrine tumours

Quality of life (QoL) measurements are increasingly being used as an end point in cancer clinical trials. Standard generic QoL questionnaires may not assess symptoms produced by neuroendocrine tumours. Here we report the development of a disease-specific quality of life score questionnaire for patients with neuroendocrine tumours of the gut to supplement the EORTC core cancer questionnaire, the QLQ-C30. Phases 1-3 of the EORTC quality of life group guidelines for module development were used to design the new questionnaire. Forty-one relevant issues (questions) were generated after an extensive literature search. Following interviews of 15 health care workers and 35 patients, a 35 question provisional questionnaire was constructed. This was translated into seven European languages and pre-tested in 180 patients resulting in a 21-item module that will be validated in an international clinical trial. The EORTC QLQ-NET21 provides a site-specific module to supplement the QLQ-C30 for patients with neuroendocrine tumours.

[Essential thrombocythemia]

New diagnostic and therapeutic aspects of the essential thrombocythemia are summarized. A series of 14 patients with essential thrombocythemia is reported.

Carcinoma of pancreatic body and tail: are there improvements in diagnosis and treatment modalities over the past decade?

BACKGROUND AND AIM OF STUDY

The aim of the present study is to assess whether or not there has been improvement in the therapeutic strategy for body-tail pancreatic carcinoma over the past decade.

PATIENTS AND METHODS

A total of 215 patients suffering from cytologically and histologically documented ductal carcinoma in the pancreatic body-tail, observed from 1990 to 1999, were analysed. Changes in tumour stage at diagnosis, in the percentage of patients treated surgically, in resectability rates and in the use of anticancer therapies over the years were sought. Survival curves were evaluated in relation to the treatments adopted.

RESULTS

Over the 10-year period, no significant differences were observed with respect to the stage at diagnosis, resectability or type of surgery adopted. There was a significant increase in the percentage of unoperated patients (p < 0.0001) and, as expected, in the percentages of patients submitted to chemo- and/or radiotherapy (p < 0.0001). With the sole exception of tumour stage in the case of patients undergoing radiotherapy, a comparison between groups revealed no element of patient selection bias other than time. The survival of patients undergoing chemotherapy is significantly better, also at multivariate analysis, than that of patients not undergoing such therapy (13 vs. 5.8 months; p < 0.0001).

CONCLUSIONS

There has been no change over the years in the direction of earlier diagnosis and the prognosis remains distinctly poor. More extensive use of anticancer therapies, however, has led to a significant increase in median survival. Radical resection, when possible, assures the longest survival.

[Effectiveness of mesoglycan in the prevention of cerebral ischemia]

40 subjects who had a transitory ischemic cerebral attack were treated with Mesoglycan and controlled for two consecutive years. Only four patients showed relapse of ischemic cerebral attacks. There was also noted a positive effect on the patients' quality of life, examined using psycometric scales.

[Effectiveness and tolerability of selegiline in the treatment of pathological cerebral involutions]

A dysfunction of dopaminergic systems with reduction of active dopamine, is well-known in cerebral involution. Twenty patients with mild-moderate pathological cerebral involution of atrophic and/or vascular origin, were treated with Selegiline (L-deprenyl), a monoamino-oxidase B inhibitor (10 mg/die for six months). Compared with a control group, Selegiline treated patients showed a statistically significant improvement in cognitive and behaviour capacities. At the end of investigation, "Mini Mental State" showed an improvement of 26.5% in Selegiline group and of 3.7% in control group (P < 0.01). "Echelle Clinique d'Aptitudes Intellectuelles" showed an improvement of 29.4% and of 10.8% respectively (P < 0.01). Selegiline treatment has shortened significantly the reaction times and has improved mnesic capacities. No side effects were observed during the study.

Characterization of a surface modified dry powder inhalation carrier prepared by "particle smoothing"

Atomic force microscopy (AFM) was used to investigate drug-carrier interactions between beclometasone dipropionate (BDP) and a series of untreated and modified lactose surfaces. This quantitative information was correlated with bulk characterization methods and an in-vitro study. Modified lactose surfaces were prepared using a proprietary process referred to as "particle smoothing" to obtain smooth carrier surfaces with or without the presence of magnesium stearate. The engineering of lactose carrier surfaces using the particle smoothing process resulted in significant differences in surface morphology when compared with the "as supplied" starting material. The energy of separation, between BDP and lactose samples, determined by AFM suggested similar lognormal distributions with a rank decrease in median separation energy (e(0.5)) (26.7, 20.6 and 7.7 microJ for untreated, particle-smoothed and particle-smoothed with magnesium stearate, respectively). A series of in-vitro twin stage impinger studies showed good correlation with the AFM separation energy measurements. The mean fine particle dose increased for the two processed lactose samples, with a significant increase for the lactose processed with magnesium stearate, 102.0+/-16 microg compared with 24.2+/-10.7 microg for the untreated lactose. Thus, the AFM presents as a possible pre-formulation tool for rapid characterization of particle interactions.

[Use of ursodeoxycholic acid combined with silymarin in the treatment of chronic ethyl-toxic hepatopathy]

30 patients, affected by chronic ethylic hepatopathy, were treated with 450 mg/daily of ursodeoxycholic acid (UDCA): after six months, a significant decrease of serum hepatic enzymes was noted. The addition of silymarin (400 mg/daily) to UDCA in other 30 patients, induced a further improvement of hepatic function.

[Reaction times during citicoline treatment]

The effects of Citicoline were investigated in 40 patients with pathological cerebral involution of atrophic origin. The dose was 1000 mg/die by parenteral injection for 4 weeks; 20 patients, after a wash-out of a week, received another cycle of Citicoline at the same doses for other 4 weeks. Citicoline treatment has shortened significantly the reaction times and has improved cognitive and behaviour capacities, evaluated according to the "Clifton test" and "Green Relatives Stress Scale". Better results were obtained in patients who received two cycles of therapy. No side effects were observed during the study.

Surgical strategy in the treatment of gastrointestinal neuroendocrine tumours

The aim of this study was to analyze the indications and type of surgery to be performed in patients suffering from the more common gastrointestinal neuroendocrine tumours. The different patterns of tumour spread are considered (local, locoregional and metastatic disease) along with the indications according to three main objectives, namely, identification of the disease, cure and care. The surgical procedures of choice in relation to the different tumour subtypes are also analyzed, and the main controversies relating to cytoreductive surgery are discussed.

Influence of layer position on in vitro and in vivo release of levodopa methyl ester and carbidopa from three-layer matrix tablets

A versatile oral controlled release system for the simultaneous delivery of levodopa methyl ester and carbidopa, consisting of a three-layer matrix tablet, has been studied and developed. Each individual layer of the matrix exhibited a different release mechanism, i.e. the first layer was swellable (S), the second one was erodible (E) and the third one was disintegrating (D). The three layers have been assembled in the monolithic matrix in different relative positions. It was found that in the monolith the three layers could interact, producing in vitro release profiles depending on their relative position. The monoliths having the configurations DSE and SDE were administered to human volunteers in order to determine the plasma profiles. The pharmacokinetic data showed a significant difference between the early time plasma curves: the monolith DSE, having the fast release profile, gave rise to a rapid appearance of a high levodopa plasma level, whereas the slower releasing monolith SDE produced a smoothed plasma concentration profile.

Early stromal invasion in cervical cancer: immunocytochemical changes occurring in infiltrating neoplastic cells

Early Stromal Invasion (ESI) in cervical cancer progression should be considered as a separate histological diagnostic category for its morphological characters very different from those of both carcinoma in situ (CIS) and microcarcinoma (MIC). To have some more microscopical details on these differences we performed immunocytochemical investigation addressed to evaluate, in cervical cancer malignancy progression, the evolutionary changes in the expression of some proteins involved in cell differentiation and cell cycle regulation. The results provide data improving the knowledge about ESI and supporting, with objective proofs, the nosological autonomy of ESI, with respect to CIS and MIC.

Cystic tumours of the pancreas: a review

The detection of a cystic tumour of the pancreas is a challenge which puts not only the surgeon's knowledge and expertise to the test, but also those of the team of radiologists and pathologists with whom he works. The diagnosis of a suspected pancreatic cystic tumour is morphological and is based on modern imaging techniques and, in the case of intraductal papillary mucinous tumours, on endoscopic findings. In the search for the correct preoperative diagnosis, however, it is of fundamental importance to bear in mind the limitations of the various instrumental investigations, and particularly those of fine-needle aspiration cytology. In this light the main morphological and clinicopathological features of serous cystadenomas, mucinous adenomas and adenocarcinomas, intraductal papillary mucinous tumours and papillary cystic and solid tumours are analysed as well as the surgical indications. In fact only the surgeon, on the basis of his knowledge of the patient's medical history and symptoms, will be in a position to determine to which nosological "cystic" entity the morphological findings described belong. A deeper knowledge of the natural history of each of these cystic tumours will help the surgeon formulate the most appropriate treatment indication. Providing the patient's condition fulfills the necessary operability criteria, resection will be mandatory whenever there exists a doubt that the tumour may be malignant or whenever its natural history suggests a malignant potential.

Infection prevention in necrotizing pancreatitis: an old challenge with new perspectives

Necrotizing pancreatitis still remains a life-threatening disease despite several improvements in diagnosis, prevention and treatment. In recent years, some important questions have been answered such as the need for early intensive medical treatment rather than early surgery, but others are still strongly debated. The aim of this paper is to present an up-to-date assessment of current challenges in the management of necrotizing pancreatitis in order to prevent infection.

Plasma and skin concentration of 5-methoxypsoralen in psoriatic patients after oral administration

The aim of this work was to investigate the distribution of 5-methoxypsoralen in the skin after oral administration of the drug and to examine the correlation between skin and plasma concentrations. 5-Methoxypsoralen skin concentration was measured in both healthy and psoriatic sites of 10 psoriatic patients after single and multiple oral doses. The results obtained show that 5-methoxypsoralen accumulates at higher levels in the more external layers of the skin after oral administration. The high affinity of drug for the stratum corneum was confirmed by in vitro skin affinity measurements. The concentration of 5-methoxypsoralen in the skin was similar in both psoriatic and healthy sites, indicating that the pathology does not influence drug distribution in the skin. After single dose administration, a linear correlation was found between skin and plasma drug concentration. After multiple dose administration, drug concentration in the skin was fairly constant despite the variable plasma concentrations in different subjects.

Solubility and conversion of carbamazepine polymorphs in supercritical carbon dioxide

The aim of this work was to investigate whether mixtures of carbamazepine polymorphs could be processed in supercritical (SC) CO(2) in order to obtain the pure stable crystalline phase. To accomplish this goal the solubility of carbamazepine polymorphs I and III in supercritical CO(2) was first assessed using a low solvent flux dynamic method. Mixtures of Form I and Form III were processed in dynamic or static conditions in SC-CO(2). Differential scanning calorimetry, Fourier transformed infrared spectroscopy, and powder X-ray diffractometry were used to analyse solid samples in terms of polymorph composition. It was found that Form I and Form III of carbamazepine have different solubility in supercritical CO(2) at 55 degrees C above 300 bar. Due to the transformation of the metastable form, conversion of Form I into Form III can be carried out on a binary mixture of the two polymorphs by treating the mixture at 55 degrees C and 350 bar, under both static and dynamic conditions, via its solubilization in supercritical CO(2).

Translocation of drug particles in HPMC matrix gel layer: effect of drug solubility and influence on release rate

The aim of this work was to study the release mechanisms of drugs having different solubility (buflomedil pyridoxalphosphate 65%, sodium diclofenac 3.1%, nitrofutantoin 0.02% w/v,) from hydroxypropyl methylcellulose (HPMC) matrices by concomitantly studying swelling, diffusion and erosion fronts movement and drug delivery. The main goal was to clarify the role played by polymer swelling in drug transport. The results showed that the rate and amount of drug released from swellable matrices was dependent not only from drug dissolution and diffusion but also from solid drug translocation in the gel due to polymer swelling. In fact, as drug solubility decreased, the slower drug dissolution rate in the gel layer allowed drug particles to be transported close to the matrix erosion front. The presence of solid particles in the gel reduced the swelling and the entanglement of polymer chains and affected the resistance of gel towards erosion. As a consequence, the matrix became more erodible. The erosive delivery accelerated after the matrix had been completely transformed into the rubbery state, particularly when a considerable amount of solid drug particles remained in the gel phase.

Controlled delivery of biotechnological products

Peptides, proteins, and nucleotides or DNA fragments are the new generation of drugs. They are becoming attractive owing to the fast development of biotechnology. The admnistration of such molecules, however, may be a problem as sensitivity to temperature, instability at some physiological pH values, short plasma half-life, and high molecular dimension, which hinders the diffusive transport, make, at the moment, parenteral route the only possible way of administration of such molecules. Controlled drug delivery that comprises the development of new administration routes could be the answer to the problems for administration of biotechnological molecules. The rational of drug delivery is to change the pharmacokinetic and pharmacodynamic of drugs by controlling their absorption and distribution. Rate and time of drug release at absorption site could be programmed using a so called delivery system. Different technologies, such as chemical (pro-drugs), biological, polymers, lipids (liposomes, LDL), have been proposed to obtain controlled drug release. Also the use of new administration routes is part of controlled drug delivery. In fact, it could increase the drug absorption and reduce the effects of the active ingredient in those districts not interested in the therapy. Drug delivery systems allowing for an effective release in vivo of new biotechnological molecules, such as recombinant antiidiotypic antibodies with antibiotic activity, devoted to the treatment of pulmonary (tuberculosis and pneumocystosis) and mucosal (candidiasis) diseases are discussed under that perspective.

Disintegration propensity of tablets evaluated by means of disintegrating force kinetics

The aim of this work was to measure the disintegrating force concomitantly with tablet disintegration, in order to evaluate the disintegration propensity of tablets. Disintegration and dissolution were measured on tablets containing two poorly soluble drugs (diclofenac sodium or ketoprofen), including different percentages of two disintegrants (Explotab or Ac-Di-Sol). Because of the experimental setup, the disintegrating force measured was the result of the force generated by disintegrant swelling and dissipated by tablet disintegration. The disintegrating force versus time curves had shapes ranging from a skewed distribution curve to a bell-shaped curve, depending on slow or rapid disintegration of tablets, respectively. Interestingly, the shape of the resulting curves was very sensitive to the composition of the tablet. When the disintegrant in the formula was increased, the force-time curve approached the bell-like shape. The disintegration propensity of the tablet can be evaluated by the disintegrating force development during disintegration. The disintegration improvement of the formula can be predicted. The disintegrating force curve allows for the clear identification of the optimal percentage of disintegrant to be used.

Swellable matrices for controlled drug delivery: gel-layer behaviour, mechanisms and optimal performance

The majority of oral drug delivery systems (DDS) are matrix-based. Swellable matrices are monolithic systems prepared by compression of a powdered mixture of a hydrophilic polymer and a drug. Their success is linked to the established tabletting technology of manufacturing. Swellable matrix DDS must be differentiated from true swelling-controlled delivery systems. This review focuses on hydrophilic swellable matrix tablets as controlled DDS. Gel-layer behaviour, front movement and release are described to show the dependence of the release kinetics on the swelling behaviour of the system. In vivo behaviour of matrix systems is also considered.

Physical properties of parabens and their mixtures: solubility in water, thermal behavior, and crystal structures

The peculiar solubility behavior of propylparaben (propyl ester of 4-hydroxybenzoic acid) in aqueous solution, when tested separately and together with methyl-, ethyl-, and butyl-parabens, has been investigated in detail. The results clearly indicate that the decrease in solubility (approximately 50% compared to the solubility value of propylparaben alone) is typical of those mixtures containing also ethylparaben, as demonstrated by solubility experiments on binary, ternary, and quaternary mixtures of the parabens. Phase diagrams of all the six binaries show that propylparaben and ethylparaben are the only pair that form almost ideal solid solutions near the melting temperatures. Moreover, phase-solubility analysis shows that propylparaben and ethylparaben, at room temperature, can also form solid solutions whose solubility is related to the composition of the solid phase at equilibrium. To achieve an independent confirmation of the possible solid solution formation that supports the above interpretation of the solubility behavior, the crystal structures of the four parabens have been examined and isostructurality has been found to exist only between ethylparaben and propylparaben. Powder X-ray diffraction has also been performed on ethylparaben, propylparaben, and their solid solutions obtained by recrystallization from water. The progressive shift of distinctive diffraction peaks with phase composition clearly indicates that propylparaben and ethylparaben form substitutional solid solutions. The small value (<1) of the disruption index provides thermodynamic support for substitutional solid solutions based on isostructural crystals.

Drug volume fraction profile in the gel phase and drug release kinetics in hydroxypropylmethyl cellulose matrices containing a soluble drug

In the present work, the drug volume fraction profiles of a colored and very soluble drug, buflomedil pyridoxal phosphate, in the gel layer of initially glassy hydroxypropylmethyl cellulose matrices were studied, using image analysis of pictures of the matrices during swelling and release. The goal was to correlate the drug release kinetics with the dynamic behavior of the drug gradient in the gel layer. An inert (nonswellable) matrix, manufactured by substituting hydroxypropylmethyl cellulose with an inert polymer and containing the same amount of buflomedil pyridoxal phosphate, was prepared as well. The drug color gradient in the partially extracted region and the flux of this matrix were compared to the swellable matrix. The drug gradient in the dissolved drug gel layer of swellable matrices was observed. It was demonstrated that drug release kinetics does not only depend on drug diffusion and matrix erosion, but also on drug dissolution in the gel and on polymer relaxation.

Observation of swelling process and diffusion front position during swelling in hydroxypropyl methyl cellulose (HPMC) matrices containing a soluble drug

The behavior of gel layer thickness in swellable hydroxypropyl methyl cellulose matrices loaded with increasing amounts of soluble and colored drug and exhibiting swelling, diffusion and erosion fronts, was studied using a colorimetric technique. The effect of the drug loading on the front position in the gel layer, in particular, on the presence of a diffusion front and its movement, was investigated. In addition, the swelling, diffusion and erosion front positions at different releasing times were measured and a theoretical analysis of the overall process was provided. It was found that the diffusion front was visible in systems with more than 30% drug, due to the presence of an undissolved drug layer. The physical analysis of such systems clearly showed the importance of drug solubility and loading in the observation of the diffusion front.

Multiple myeloma index: verification of a new prognostic approach with evaluation of treatment response

BACKGROUND AND OBJECTIVE

Currently adopted prognostic criteria for multiple myeloma (MM) still lack reliable predictive ability to select subsets of patients for different therapies, in particular for intensive treatment protocols. In this work we aimed to test the prognostic value of the MM Prognostic Index (MMPI), developed in 1996 by Grignani et al. from Pavia University as a clinical and investigational tool.

DESIGN AND METHODS

Ninety-three MM patients were eligible for the study. All received initial induction therapy based on a standard 6-month melphalan + prednisone (M + P) protocol. Clinical and laboratory parameters, conventional staging and bone marrow infiltration percentage and cytopathology (BMIC) were assessed at diagnosis, while treatment response (TR) was evaluated using criteria after induction therapy. Cox's multivariate survival analysis was applied on prognostic data.

RESULTS

In our patients independent prognostic value was confirmed for British Medical Research Council staging, BMIC and TR, the three factors considered in MMPI. Risk classes obtained via MMPI identify patients with different outcomes; moreover, the index discriminates significantly among Stage II patients.

INTERPRETATION AND CONCLUSIONS

This new approach to MM prognosis is simple and reliable from the prognostic point of view; it refers not only to neoplastic mass, but also to intrinsic proliferative capacity of the malignant clone and to tumor-host interactions. We recommend its adoption in clinical practice and in the evaluation and design of therapeutic trials.

Partial permselective coating adds an osmotic contribution to drug release from swellable matrixes

A swellable matrix tablet is described which is partially coated with cellulose acetate (CA) to obtain a film having the shape of a cup, whose permeability to water and solutes was altered by mixing increasing amounts of poly(ethylene glycol) 400 (PEG). The drug-release mechanism from such systems was assessed by carrying out drug-release experiments both in water and saline solutions. Drug permeability through the polymeric cup and SEM analysis on the films were also performed. It was found that the systems exhibited drug-release kinetics very close to linearity. The mechanisms governing drug release were (i) drug diffusion through the uncoated gel layer, (ii) drug transport through the gel layer due to the osmotic pressure difference, and (iii) drug diffusion through the cup pores. The relative importance of each contribution depended on the amount of PEG in the film. The systems with a cup containing 1%, 13%, and 33% PEG w/w behaved in part as osmotic systems, whereas the system having a permeable cup behaved as a hybrid reservoir system. These modifications of the coating permeability introduce a further possibility of modulating drug-release kinetics and lead to a reduced dependence of swellable matrix tablet release on environmental conditions.

Transdermal iontophoresis of salmon calcitonin can reproduce the hypocalcemic effect of intravenous administration

Salmon calcitonin (sCt) was administered by transdermal iontophoresis in rabbits, using a new drug reservoir assembled directly on the skin, based on a dry disc containing sCt to be dissolved at the application site. The hypocalcemic effect was taken as a measure of the pharmacodynamic response. In rabbits, the results obtained show that salmon calcitonin skin penetration by iontophoresis, using pulsatile current of 0.8 mA/cm2 on a reservoir containing 100 IU/Kg of sCt, was governed by the quantity of electric charge applied, mimicking the hypocalcemic response of 10 IU/Kg intravenous administration.

Verification and comparison of two different predictive equations in Hodgkin's disease

BACKGROUND AND OBJECTIVE

In recent years, two predictive equations to estimate median expected survival at diagnosis for patients affected with Hodgkin's disease have been developed at the University of Pavia Medical School. The present retrospective work was aimed at testing correlation between mean survival estimated using the two equations and observed survival, and at comparing the results of the two different equations.

METHODS

Fifty-three deceased patients were considered from a series of 114 consecutive ones. All these patients had been treated in a conventional way according to therapeutic modalities similar to those used in the series from which the two equations were derived. Expected median survival values calculated with the older, linear equation and with the newer exponential one were compared with observed survival.

RESULTS

Mean survival of the whole series was over 24 years, with survival probabilities of 85% after 5 years and 74% after 10 years. Using the first predictive equation on the 53 deceased patients resulted in a satisfactory correlation between estimated median survival and real survival: Pearson's R correlation coefficient value is 0.5996, with a t value of 5.35 and p < 0.001. The more recent exponential predictive equation showed a better correlation between estimated median survival and observed survival: R = 0.7338, t = 7.71, p < 0.001.

INTERPRETATION AND CONCLUSIONS

The new exponential equation, while apparently complex, is superior to the older one, and is a very reliable and straightforward tool for estimating median expected survival: its forecast proves to be an important pretreatment parameter in every HD patient. These observations support widespread use of this tool in clinical practice to evaluate the prognosis of Hodgkin patients in a more accurate and flexible way.

Drug reservoir composition and transport of salmon calcitonin in transdermal iontophoresis

PURPOSE

The aim of the work was to study iontophoretic transdermal administration of salmon calcitonin (sCt) in rabbits, with particular attention to drug reservoir composition. A dry sCt disc, to be dissolved on the application site, was used for preparing the reservoir for transdermal iontophoresis. As a reference drug reservoir, a pad wetted with drug solution was used.

METHODS

Experiments were done in rabbits depositing 100 IU of salmon calcitonin on skin and applying anodal iontophoresis. Serum calcium concentration was measured during iontophoresis, passive diffusion and after i.v. administration. Parameters such as pH value and reservoir type were examined.

RESULTS

Transdermal iontophoresis of sCt elicited a decrease in the serum calcium level, whereas, in the absence of electric current, no significant fall was measured. Using the reservoir prepared from drug solution, anodal iontophoresis at pH 4.2 was more effective than at pH 7.4, probably due to higher sCt net positive charge. Using the reservoir prepared from dry disc, similar kinetics and extent of drug effect were observed at both pH values. The reservoir prepared from solid drug deposit concentrated sCt next to the skin.

CONCLUSIONS

Anodal iontophoresis for transdermal calcitonin administration shows therapeutical applicability. The type of reservoir is an important parameter affecting sCt transdermal iontophoresis.