Investigation of curcumin-cyclodextrin inclusion complexation in aqueous solutions containing various alcoholic co-solvents and alginates using an UV-VIS titration method. Studies of curcumin and curcuminoides, XXXV

The effect of pharmaceutical excipients like alcoholic co-solvents and water-soluble polymers on the inclusion complexation of curcumin in hydroxypropyl-beta-cyclodextrin and hydroxypropyl-gamma-cyclodextrin was investigated with a UV-VIS titration method. The association constants and the stoichiometries of the inclusion complexes in buffered media containing various amounts dl of alcoholic co-solvents and alginates were determined. The results showed a 1 : 1 stoichiometry between curcumin and both the cyclodextrins investigated in buffered media containing 10% (v/v) alcoholic co-solvents, although some 1 : 2 (host:guest) complexation was suspected between curcumin and hydroxypropyl-beta-cyclodextrin. The presence of 0.1% (w/v) sodium alginate or propylene glycol alginate did apparently not change the stoichiometry of the complexes formed. Curcumin was found to have a more than 30-fold higher association constant with hydroxypropyl-gamma-cyclodextrin compared to hydroxypropyl-beta-cyclodextrin in buffer containing 0.5% ethanol. Large variation in the association constants between curcumin and the cyclodextrins as a result of different co-solvents in the aqueous complexing media were found. A decrease in the association constant was seen as the chain lenght of the added co-solvent increased. Further, a decrease in the association constants was observed by addition of alginates in the case of hydroxypropyl-gamma-cyclodextrin at 0.5 or 5% (v/v) ethanol. The trend was opposite in the case of hydroxypropyl-beta-cyclodextrin, where a 30-90% increase in the association constant was observed in the presence of alginates. The results in the current study showed the large variations in the complexation between curcumin and hydroxypropyl-beta-cyclodextrin and hydroxypropyl-gamma-cyclodextrin, resepctively, as a result of various alcoholic co-solvents and alginates in the complexing media. The results also illustrated the importance of optimizing the solvent systems when utilizing cyclodextrins as drug carriers.

Prostaglandins, renin, aldosterone, and catecholamines in preeclampsia

Urinary excretion of prostaglandin E2 (PGE2) and F2 alpha (PGF2 alpha), plasma concentrations of renin (PRC), aldosterone (PAC), noradrenaline (PNA) and adrenaline (PA) were determined in the third trimester of pregnancy, 5 days and 3 months after delivery in preeclampsia and normotensive pregnant and non-pregnant control subjects. PGE2 was higher in pregnant control subjects than in non-pregnant subjects, but reduced to non-pregnant level in preeclampsia. PGF2 alpha was the same in preeclampsia and normotensive pregnancy but higher than in the non-pregnant group. PRC and PAC were increased during pregnancy, but considerably lesser in preeclampsia than during normotensive pregnancy. PNA and PA were the same in all three groups. All parameters were normal 3 months after delivery. There were no correlations between any of the hormones and blood pressure in any of the groups. PGE2 was positively correlated to PRC. The lack of renal PGE2 in preeclampsia might be responsible for the decrease in renal blood flow and sodium excretion, and the changes in PRC and PAC are supposed to be secondary to changes in PGE2. It is hypothesised that preeclampsia is a state of prostaglandin deficiency.

Seroprevalence of HIV/HBV coinfection in Malian blood donors

OBJECTIVES

A cross-sectional study was conducted to assess the prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and their coinfection among blood donors at the National Blood Transfusion Center in Bamako, Mali, from November 2001 to July 2002.

METHODS

Enzyme-linked immunosorbent assay techniques with reagents from Bio-Rad (France) were used to test the blood samples.

RESULTS

11,592 blood donors were tested for HIV and HBV surface antigens. The prevalence of HIV was 4.5% and the prevalence of HBV was 14.9%. The HIV/HBV coinfection rate was only 1.13% in this population.

CONCLUSION

The coinfection rate was unexpectedly low in this blood donor population where monoinfection with HIV or HBV prevalence was high.

Influence of formulation properties on chemical stability of captopril in aqueous preparations

The influence of various formulation properties on the chemical stability of captopril in aqueous media at pH 3 was investigated, in order to reformulate and increase the shelf-life of an oral mixture of the drug. At this pH, chemical stability is improved by an increase in drug concentration (1-5 mg/ml) and a decrease in temperature (5-36 degrees C), the latter demonstrated by a linear Arrhenius-plot. The activation energy is low (Ea = 10.2 kcal/mol), thus the Q10 value is only 1.8 in pure aqueous solutions. The degradation at the lowest concentration investigated in pure aqueous solution apparently follows zero order kinetics. The reaction order is changed at higher concentrations. We are presenting a hypothesis of intramolecular proton transfer from the thiol to the ionized carboxylic group as the initial step in the oxidative degradation pathways of captopril. Long-term stability of 1 mg/ml captopril in aqueous solutions at pH 3, stored at 36 degrees C for one year, shows that the sugar alcohol sorbitol accelerates degradation of the drug while Na-EDTA at a concentration as low as 0.01% is sufficient to stabilize these samples. Purging with N2-gas prior to storage is not essential for drug stability, as long as Na-EDTA is present. Only at a low level of Na-EDTA (0.01%) combined with a high level of sorbitol (35%), purging with N2-gas appears to have a small effect. The destabilizing effect of sugar alcohols is confirmed by accelerated degradation also in the presence of glycerol. The efficient stabilization in the presence of Na-EDTA at a low concentration indicates that the metal-ion-catalyzed oxidation pathway dominates the chemical degradation process at low pH, although several mechanisms seem to be involved depending on excipients present.

In vitro release of curcumin from vehicles containing alginate and cyclodextrin. Studies of curcumin and curcuminoides. XXXIII

Combinations of cyclodextrins and alginates were used to solubilize the hydrophobic compound curcumin in aqueous vehicles intended for topical delivery. A careful selection of the excipients is necessary to achieve a sufficient release of curcumin towards a membrane of hydrophilic character, e.g. mucosa. The aim of the study was to investigate the effect of different combinations of cyclodextrins and alginates on curcumin release towards hydrophilic membranes in vitro. The curcumin flux through semi-permeable membranes of different molecular weight cut-off was measured to differentiate between the flux of curcumin in its uncomplexed form (restricted flux), its uncomplexed form together with its inclusion complexes (partly restricted flux) and the overall flux of curcumin-cyclodextrin complexes and uncomplexed curcumin (unrestricted flux). A high viscosity of the vehicle was expected to inhibit curcumin flux. Vehicles containing 3% alginate were found to have lower unrestricted flux than the vehicles containing 0.5% alginate independent of the type of cyclodextrin used. The results indicate that the unrestricted curcumin flux (e.g. in the case of wounded skin) is rather independent of the composition of the hydrophilic vehicle and mostly limited by the viscosity. However, partly restricted and restricted curcumin flux were found to depend on both the viscosity and the composition of the vehicles. The cyclodextrin with the demonstrated lowest solubilisation capacity (i.e. hydroxypropyl-beta-cyclodextrin) resulted in the highest values of both the restricted and unrestricted curcumin flux. In conclusion, a combination of hydroxypropyl-beta-cyclodextrin and propylene glycol alginate seemed to be the best choice with respect to curcumin solubility and release from the vehicle.

Influence of lag-time between light exposure and color evaluation of riboflavin in the solid state

The lag-time between sample light exposure and evaluation of the samples strongly influences the observed change in surface color of riboflavin bulk substance and tablets. The decrease in total color change (deltaE*ab) as a function of time after exposure is ascribed to a change in the surface moisture content of the samples during storage. Our results emphasize the need for a standardization of the lag-time between light exposure and sample evaluation in the photostability testing protocol of drug substances and products.

Syndromic management training for non-formal care providers in Pakistan improves quality of care for sexually transmitted diseases STD care: a randomized clinical trial

We conducted a randomized, controlled, three-armed trial to assess whether training in syndromic management, with provision of packets, could improve the quality of STD services provided among non-formal care providers. The quality of STD case management service, observed by "incognito patients" in both intervention groups, improved substantially compared to the control group (p < 0.05). The training-and-packets group performed better in service delivery, HIV-testing referral, and condom provision when compared to the training-only group (all p < 0.05). The training-and-packets group also retained more knowledge and practiced more skillfully at six months post-intervention when compared to the training-only group (p < 0.05). Exit interviews of clients suggested that 81% of providers in the intervention groups offered advice on condom use when compared to none of those in the control group (p < 0.001). Syndromic management training and free syndrome packets for non-formal providers had a positive impact on the quality of STD care among the trained providers.

HIV-infected workers deported from the Gulf States: impact on Southern Pakistan

HIV prevalence is still very low in Pakistan, but its south Asian location and subgroups with recognized lifestyle risk factors suggest that Pakistan will experience expanded diffusion of HIV. We report the frequency of HIV infections identified by the AIDS Control Programme in the Sindh province of Pakistan. Most HIV positive cases currently reported to the Sindh AIDS Control Programme are found among Pakistani workers deported from the Gulf States and among foreigners. The 58 returned workers with HIV represent 61 to 86% of reported cases in any given year during the 1996-1998 period. Five wives of returning workers have been identified with HIV. Expatriate workers in the Gulf States are tested for HIV routinely, unlike other subgroups in Pakistan. Considering the risk of HIV/AIDS due to regular introduction of HIV from returned workers, and the limited awareness surrounding sexual health and HIV/STD transmission issues in Pakistan, intervention programmes targeted at overseas workers need to be implemented to control the expansion of the HIV epidemic in Pakistan (Int J STD AIDS 1999;10:812-14).

Photoreactivity of biologically active compounds. XVII. Influence of solvent interactions on spectroscopic properties and photostability of primaquine

The influence of solvent interactions on absorption properties, fluorescence properties (emission spectra and quantum yields) and relative photochemical degradation rates of primaquine has been investigated, in order to evaluate photochemical reaction mechanisms and chemical properties of the compound. The first absorption band (n - pi*) of primaquine is only slightly dependent on properties of the solvent, which can be ascribed to a strong, intramolecular hydrogen bond between the quinoline N and amine group in the ground state (S0). Amphiprotic solvents with predominant acidic properties (water and methanol) will to some extent stabilize the molecule and initiate hypsochromic shifts of the absorption band by protic interactions, while the other solvents (amphiprotic, basic and neutral) influence the absorption spectrum by general solvent effects only. The excited singlet (S1*) state of primaquine interacts more efficiently with the surrounding solvents than the S0 state, as evaluated by the Stokes shifts. The pKa value of the quinoline N is likely to increase in the S1* state, which is important for the observed protic interactions with amphiprotic solvents of predominant acidity. Specific solvent effects are highly important for the efficiency of the fluorescence (fluorescence quantum yields; phi f). The fluorescence is quenched by amphiprotic solvents, likely due to a rupture of the intramolecular bond and protonation of the quinolone N, and enhanced by polar, non-protic (basic) solvents, probably by stabilization of the delta intramolecular hydrogen bond. The observed photochemical degradation rates of primaquine in amphiprotic media are positively correlated with phi f, indicating that the photochemical degradation of primaquine is dependent on intramolecular hydrogen bonding and non protonated lone-pair electrons at the quinoline N. The intramolecular ring-formation with a subsequent increased lipophilic character and (lack of) interactions with the surroundings, are important factors for biological behavior as well as pharmaceutical properties of primaquine. Knowledge about solvent interactions with primaquine in the S0 and S1* states is essential for the proceeding evaluation of photostability and phototoxicity of the drug.

Photostability of symphatomimetic agents in commonly used infusion media in the absence and presence of bisulfite

Previous studies have indicated that epinephrine is photodegraded in sulfite-containing solutions by adrenochrome sulfonate. The present study was undertaken to investigate if the same degradation pattern is found for the symphatomimetic compounds isoprenaline, dopamine, and metaraminol. It was found that isoprenaline and dopamine followed the same degradation pattern as epinephrine--they are photodegraded more rapidly in the presence of bisulfite than in its absence, probably by formation of an aminochrome sulfonate. Metraminol was photostable under the given conditions. The photostability of isoprenaline, dopamine, and epinephrine was further investigated in the infusion media sodium chloride (9 mg/ml), glucose (50 mg/ml), Macrodex (dextran 70, 60 mg/ml, sodium chloride 9 mg/ml) and Ringer acetate. The influence of pH, conductivity, viscosity and media concentration were analyzed. In the presence of bisulfite it was found that Ringer acetate had a photodestabilizing effect, while Macrodex had a slight photoprotective effect, on the catecholamines. The pH of the media was shown to be the most important factor, a low pH being protective. Glucose had a destabilizing effect on epinephrine, dopamine, and isoprenaline in the absence of bisulfite.

Marginal validity of syndromic management for reproductive tract infections among pregnant women in Jamaica

We assessed the validity of a syndromic case management approach for reproductive tract infections (RTIs) among 371 pregnant women attending antenatal care facilities in Kingston, Jamaica, using an algorithm previously validated in high-risk Jamaican women. For our antenatal attenders, the algorithm had low sensitivities for all RTIs (66.7% for cervicitis, 35.4% for trichomoniasis, 11.1% for bacterial vaginosis (BV) and 24% for candidiasis). Specificities for BV (88.9%) and candidiasis (81.1%) were higher than for cervicitis (62.8%) and trichomoniasis (68.5%). The positive predictive values were lower than 36% for all diagnoses, especially BV (6.9%). Syndromic management of RTIs in pregnant women was problematic using a clinical algorithm that had worked well for high-risk women. Syndromic management for RTIs in Jamaican antenatal clinics is only a temporary solution until more simple and affordable diagnostic tests for RTIs are developed and/or until laboratory support and clinical care can be upgraded at antenatal clinics.

Photostability of epinephrine - the influence of bisulfite and degradation products

Sulfites are previously demonstrated to increase the photodegradation of epinephrine. The aim of this study was to clarify the factors responsible for this effect. Adrenochrome sulfonate seems to be the important substance. Photoproduction of singlet oxygen is indicated to be the mechanism by which adrenochrome sulfonate acts. Protection of epinephrine solutions from irradiation <418 nm prevented the photodegradation. A reaction pathway for thephotochemical decomposition of epinephrine in the presence of bisulfite is suggested.

CT slice index and thickness: impact on organ contouring in radiation treatment planning for prostate cancer

Objective: To assess the impact of CT slice index and thickness (3 mm versus 5 mm) on (i) prostate volume, dimensions, and isocenter coordinates, (ii) bladder and rectal volumes, and (iii) DRR quality, in the treatment of prostate cancer. Methods: 16 patients with prostate cancer underwent two planning CT‐scans using 3 and 5 mm slice index/thickness. Prostate, bladder, and rectum were outlined on all scans. Prostate isocenter coordinates, maximum dimensions, and volumes were compared along with bladder and rectal volumes. Bladder volumes and maximum diameters were further investigated using a second observer. A comparative analysis of DRR quality was conducted as well as a dosimetric analysis using DVH. Results: The differences in measurements of prostate volume, isocenter coordinates and maximum dimensions between the 3 and 5 mm scans, were small and not statistically significant. Similar finding was seen for rectal volume. However, bladder volume was always larger on the 3 mm scan (mean difference=27.9 cc;  SE=4.8 cc;  95% CI:  17.7−38.2 cc;  p<0.001) and the findings were reproduced with the second observer (mean difference=31.9 cc;  SE=4.7 cc;  95% CI:  21.9−41.9 cc;  p<0.001). The differences in volume are caused by a slight increase in (1) the measurement of the longitudinal dimensions on the 3 mm scans, and (2) the slice by slice measured bladder area on the 3 mm scans. The latter is due to partial volume effect. The 3 mm DRR were slightly better than the 5 mm DRR. The bladder DVH differed significantly in some patients. Conclusion: Bladder volume is significantly larger on the 3 mm scans. Differences in contoured areas may be accounted for, in part, by the partial volume effect.

PACS number(s): 87.57.–s, 87.53.–j

Vaginal infections in pregnant women in Jamaica: prevalence and risk factors

Trichomoniasis, bacterial vaginosis (BV) and candidiasis are reproductive tract infections (RTIs) of the vagina. We conducted a cross-sectional study in 4 prenatal clinics in Kingston, Jamaica, to estimate the prevalence of these infections and the risk factors that may facilitate their transmission among pregnant women. Of the 269 women studied, 18.0% had culture-positive trichomoniasis, 44.1% had BV (Nugent score > or = 7) and 30.7% were positive for candidiasis by wet mount. A multiple logistic regression analysis showed that having a malodorous discharge was associated with trichomoniasis (odd ratios [OR]=3.9, confidence intervals [CI]=1.04-14.7) and BV (OR=3.4, CI=1.3-8.7). Women who took action to prevent HIV infection had lower BV prevalence (OR=0.34, CI=0.12-0.98). Women who were employed were less likely to have any of the infections (OR=0.61, CI=0.36-1.03). The strong association of a symptomatic presentation with trichomoniasis and BV suggests the merit of considering syndromic management of vaginitis in this population.

Formulation and characterisation of primaquine loaded liposomes prepared by a pH gradient using experimental design

The effect of different formulation factors (lipid type, cholesterol, charge, internal buffer capacity, drug-to-lipid incubation ratio) on the encapsulation efficiency and size of primaquine liposomes (SUV's) in response to a pH gradient was investigated by a fractional factorial screen ing design. Three of the factors (charge, internal buffer capacity, drug -to-lipid incubation ratio) were further studied in a Box--Behnken optimisation design. The lipid type was the most important parameter followed by the drug-to-lipid incubation ratio, buffer capacity, cholesterol and charge. Several of the interactions wer e important. In the optimisation design a robust region with high encapsulation efficiency (>95%) was obtained for DSPC: 33.33 mol% cholesterol-liposomes at high internal citrate concentration (200 mM) by maintaining the drug-to-lipid incubation ratio below 0.15:1 (mol:mol) and varying the charge incorporation between 2 and 10%. In order to achieve long-term stability and sterility, the liposomes were lyophilised followed by gamma irradiation. The pH gradient was maintained during this treatment with little chemical degradation of the substances. The final preparation consisted of three separate vials with lyophilised liposomes, solid state primaquine and hydration medium.

HIV-infected workers deported from the Gulf States: impact on Southern Pakistan

HIV prevalence is still very low in Pakistan, but its south Asian location and subgroups with recognized lifestyle risk factors suggest that Pakistan will experience expanded diffusion of HIV. We report the frequency of HIV infections identified by the AIDS Control Programme on the Sindh province of Pakistan. Most HIV-positive cases currently reported to the Sindh AIDS Control Programme are found among Pakistani workers deported from the Gulf States and among foreigners. The 58 returned workers with HIV represent 61 to 86% of reported cases in any given year during the 1996-1998 period. Five wives of returning workers have been identified with HIV. Expatriate workers in the Gulf States are tested for HIV routinely, unlike other subgroups in Pakistan. Considering the risk of HIV/AIDS due to regular introduction of HIV from returned workers, and the limited awareness surrounding sexual health and HIV/STD transmission issues in Pakistan, intervention programmes targeted at overseas workers need to be implemented to control the expansion of the HIV epidemic in Pakistan.

An update on the prevalence of HIV/AIDS in Bangladesh

The National AIDS Committee was formed in 1985 to develop and support policies that prevent transmission of human immunodeficiency virus (HIV). In 1990, the Institute of Epidemiology, Disease Control and Research in the Ministry of Health began sero-surveillance for AIDS/HIV infection. Convenience sampling was conducted among prisoners, sailors, truckers, antenatal attendees, repatriated Bangladeshi workers, and brothel-based prostitutes in Dhaka. In 1994, commercial sex workers in other high-risk areas were included in surveillance activities. Among over 75,700 HIV tests through 1998, 119 have been confirmed positive for HIV. While the cumulative HIV prevalence rate was only 1.5/1,000 tests, it was significantly higher among men (p < 0.0001) than among women. The rates among men were as high as 28/1,000 tests in 1996 and 21/1,000 tests in 1997. Almost 50% of the reported HIV cases are from cities on the border of India and Myanmar. It is anticipated that HIV transmission will increase further given the high prevalence of risk behaviors, core high-risk groups, and extreme poverty.

[Ambulatory tonsillectomy. Is postoperative hemorrhage a risk factor?]

Out-patient surgery is being used increasingly to improve health care efficiency. In Norway, tonsillectomy is performed on an in-patient basis because of concern for the safety regarding primary haemorrhage. This study aims at investigating the safety of out-patient tonsillectomy by defining the incidence and timing of primary haemorrhage, thereby establishing a safe time period span for a possible discharge on the same day. Retrospectively recorded data on 1,632 tonsillectomies were reviewed. Serious primary post-tonsillectomy haemorrhage arose in 24 patients (1.5%). In view of the fact that one fifth of these tonsillectomy patients experience a serious primary post-tonsillectomy haemorrhage more than eight hours after the operation, tonsillectomy cannot be recommended as a safe routine out-patient procedure.

Photoreactivity of biologically active compounds, XIV: influence of oxygen on light induced reactions of primaquine

The influence of molecular oxygen and oxygen radicals on the photoreactivity of the antimalarial drug primaquine (PQ) has been investigated. Oxygen is directly involved in photodecomposition of the drug. Flushing with helium gas prior to and during irradiation to suppress the oxygen level of the medium, retards the degradation rate of PQ (followed by HPLC) and leads to the formation of only two degradation products (identified by MS) compared to eight main- and several minor products under normal atmospheric conditions. Flushing with oxygen gas prior to and during irradiation to increase the oxygen content of the medium accelerates the degradation rate of PQ. PQ produces oxygen radicals (hydroxyl and superoxide) during photolysis, while the photoproducts of PQ seem likely to induce singlet oxygen formation (detected by addition of radical scavengers). Sensitization reactions involving singlet oxygen lead to decomposition of PQ (followed by HPLC). On the basis of our results, photochemical reaction mechanisms of PQ are postulated and discussed. At physiological conditions (aqueous, neutral pH, oxygen rich) PQ has a large potential to decompose after light absorption. The photoreaction seems to be initiated at the quinoline nitrogen. The ability to form an intramolecular hydrogen bond seems to be essential for the luminescence properties of the drug. Phosphorescence lifetime of PQ is about 5 microseconds. Fast chemical reactions may occur from the short-lived triplet state of the drug, but the excited compound can diffuse only a limited distance prior to deexcitation. This can be important concerning light-induced adverse effects which may appear after medication with PQ.

[Is postoperative hemorrhage a risk in ambulatory tonsillectomy?]

Day-case surgery is being used increasingly to improve health care efficiency. In Denmark, tonsillectomy is performed on an in-patient basis because of safety concerns regarding primary haemorrhage. This study aims at investigating the likely safety of day-case tonsillectomy by defining the incidence and timing of primary haemorrhage and thereby to establish a safe time period for a possible same day discharge. Retrospectively recorded data on 2,888 tonsillectomies were reviewed. Serious primary posttonsillectomy haemorrhage arose in 34 patients (2.7 percent), of which 65 percent presented within eight hours and 95 percent within 23 hours postoperatively. In view of the fact that one quarter of the patients with a primary posttonsillectomy haemorrhage experience it more than 12 hours postoperatively, tonsillectomy cannot be recommended as a safe routine day-case procedure.

Health profile of Danish army personnel

The purpose of the present study was to delineate a health profile of professional Danish army personnel. Two-hundred twenty officers, noncommissioned officers, and gunners on active duty at Varde Barracks, housing the South Jutland Artillery Regiment and the Danish Army Artillery School, were asked about their physical and psychological health, interpersonal relations, and working conditions as well as their dietary, drinking, and smoking habits. Measurements were made of resting pulse rate, blood pressure, height, weight, waist and hip girth, and pulmonary function. The ratio of waist-to-hip girth and body mass index (BMI) were calculated. Psychological well-being was evaluated using the 12-item version of the General Health Questionnaire (GHQ). Psychosomatic symptoms were frequently reported, but very few of those surveyed appeared to have psychiatric disorders as measured by the GHQ. Also, somatic health problems were frequently reported, the most frequent being lower-back pain, mild chest pain, and sensory disorders. Differences in interpretation and reporting of "lasting health problems" may explain the relatively high score for this question. The interpersonal relations, both upward and downward in the hierarchy rank order, received high scores. Compared with the general population, alcohol consumption was very low, whereas smoking-in particular heavy smoking-was much more frequent among professional Danish army personnel. Lung function testing showed significantly poorer mean values of forced expiratory volume in 1st second of expiration and mean forced expiratory flow 25 to 75% of forced vital capacity among smokers compared with nonsmokers, although the mean values for the whole group of both smokers and nonsmokers were well above reference values for all lung function parameters. The frequency of moderately overweight individuals (25 < BMI < or = 30) was significantly higher among the male army personnel than in the general population, whereas this was not the case for obesity (BMI > 30). Abdominal obesity, regarded as an independent risk factor for the development of ischemic heart disease, stroke, diabetes, hypertension, and all-cause mortality, was present in 5%, and 3% belonged to the highest-risk group by having a low BMI as well as abdominal obesity.

Clinical use of asymmetric collimators

PURPOSE

To illustrate some of the radiation treatment techniques with asymmetric collimators in one field dimension.

METHODS AND MATERIALS

Treatment planning for various sites is done with an in-house developed treatment planning system. Dose distributions in the central plane are illustrated.

RESULTS

The use of asymmetric collimation, in addition to being a replacement for cerrobend and lead blocks, can facilitate treatment setup with boost fields and with half-beam asymmetric fields as in matching two adjacent fields, in avoiding nearby critical organ or tissue, and in tangential breast treatment. The use of asymmetric collimators would alter the dose distribution across the radiation field and should be accounted for during treatment planning. In conjunction with arc rotation or multiple asymmetric fields, two-dimensional conformal radiotherapy is possible.

CONCLUSION

The full potential of asymmetric collimation requires the use of a proper treatment planning algorithm. Some of the treatment techniques with asymmetric collimation in one field dimension are shown here.

Post-operative nocturnal hypoxia in septoplasty: the value of nasal packing with airway tubes

Nasal obstruction influences respiration during sleep and post-operative nasal packing may cause nocturnal oxygen desaturation and obstructive sleep apnoea. In order to investigate the influence of nasal packing with airway tubes on post-operative hypoxia during sleep, the oxygen saturation was monitored perioperatively in 18 patients, undergoing septoplasty followed by nasal packing using Merocel packs with airway tubes. For the group as a whole, no significant perioperative change of either median minimal or median mean oxygen desaturation could be demonstrated. A similar, non-significant perioperative prolongation of the relative time of nocturnal oxygen desaturation, expressed as per cent of the total nocturnal observation time, was seen. The results indicate that nasal packing with airway tubes may prevent post-operative hypoxia during sleep, but further investigation of post-operative nocturnal hypoxia and nasal packs, is needed.

Ultrasonographically guided fine-needle aspiration biopsy of intrathoracic tumors

PURPOSE

Evaluation of diagnostic accuracy and complication frequency at ultrasonographically guided fine-needle aspiration biopsy of intrathoracic tumors.

MATERIAL AND METHODS

A total of 134 ultrasonographically guided percutaneous fine-needle aspiration biopsies were performed on 128 patients with intrathoracic tumors abutting on the pleura. A cytologic diagnosis was obtained in 119 patients (93%).

RESULTS

In 83 patients, cytologic malignancy was found; in 34, benignity; and in 2, cellular atypia. A total of 117 diagnoses were correct and 2 diagnoses were false-positive. A malignancy subtyping based on the cytologic aspirates was made in 80 patients. In 40 (93%) of 43 histologically proven subtypes, the subtyping was correct. The complication frequency in terms of pneumothorax was 3.7%.

CONCLUSION

Ultrasonographically guided percutaneous fine-needle aspiration biopsy is a safe and reliable method of establishing the cytologic diagnosis of intrathoracic tumors.

Mediastinal staging of non-small-cell lung cancer: computed tomography and cervical mediastinoscopy

The exact indications for computed tomography (CT) of the thorax and mediastinoscopy (MS) in lung cancer still remain incompletely defined. The present study was designed to establish a standard approach to cervical MS for otolaryngologists, who in Denmark are traditionally involved in the staging of non-small-cell lung cancer (NSCLC). Sixty-four potentially operable patients with NSCLC underwent thoracic CT prior to bronchoscopy and cervical MS. Cervical MS alone established the histological diagnosis in 20% of the patients. In diagnosing lymph node metastases in the superior mediastinum, a criterion of 10 mm for abnormal enlargement resulted in an overall sensitivity and specificity of mediastinal CT of 81 and 84%, respectively, and the overall false-negative and false-positive rates appeared to be 10 and 29%, respectively. It could be demonstrated that mediastinal lymph nodes in patients with mediastinal metastases were significantly larger than mediastinal lymph nodes in patients without metastases. No clinicopathological characteristics could be identified to influence the accuracy of CT, except for the finding that the rate of false-negative mediastinal CT was significantly higher in patients with right-sided than in patients with left-sided lesions. It is concluded that because of the relatively low sensitivity and specificity of mediastinal CT, cervical MS remains essential in the evaluation of patients with presumed or verified NSCLC and that cervical MS, in experienced hands, is a safe and accurate procedure. For Danish otolaryngologists, the strategy of routine cervical MS, performed under general anaesthesia in the same stage as bronchoscopy, is advocated as a standard approach to mediastinal assessment for the staging of NSCLC. However, thoraco-abdominal CT is advocated for all patients with NSCLC, in whom operation is contemplated, as a supplementary investigation after other routine diagnostic and staging procedures, including cervical MS, have been carried out.

Polypoidal carcinosarcoma of the oropharynx: a clinicopathological and immunohistochemical study

Polypoidal squamous cell carcinomas, with a sarcomatous stroma, in the upper aerodigestive tract are very rare but well described tumours. They are associated with a multifarious nomenclature because of different opinions regarding their histology and histogenesis. The main issue is whether the stroma component is a true sarcoma or a benign reactive lesion. In order to draw the attention of otolaryngologists and pathologists to the characteristic features of this rare tumour, two cases originating from the oropharynx are presented. Both tumours were pedunculated and polypoidal, and their bulk consisted of a bizarre sarcoma-like stroma covered with granulation tissue. In some areas of the surface, however, atypical squamous cell epithelium with foci of invasive carcinoma was found. In the vicinity of the latter both tumours contained areas of adenocarcinoma. After surgical excision followed by radiation therapy, there was no recurrence after two and five years, respectively. The histological and immunohistochemical findings support the assumption that these two tumours are carcinosarcomas. Adenocarcinomatous elements in this type of tumour have to our knowledge been reported only twice previously and have never been observed in the pharynx.

Mediastinal staging of lung cancer. Is mediastinoscopy still essential?

The significance of computed tomography of the thorax and mediastinoscopy in pretherapeutic mediastinal assessment for the staging of lung cancer remains controversial. The presents study was designed to establish a standard approach to cervical mediastinoscopy for otolaryngologists, who in Denmark traditionally are involved in the staging of non-small cell lung cancer. Sixty-four potentially operable patients with non-small cell lung cancer underwent thoracic computed tomography prior to bronchoscopy and cervical mediastinoscopy. Thirty-six of the 43 mediastinoscopically negative patients additionally underwent thoracotomy, which in 32 cases was considered curative. Mediastinoscopy alone established the lung cancer diagnosis in 20% of the patients. In diagnosing lymph node metastases in the superior mediastinum, a criterion of 10 mm for abnormal enlargement resulted in an overall sensitivity and specificity of mediastinal computed tomography of 72% and 85%, respectively, and the overall false-negative and false-positive rates appeared to be 18% and 25%, respectively. No clinicopathological characteristics could be identified that influenced the occurrence of mediastinal metastases or the accuracy of computed tomography. It is concluded that mediastinoscopy remains essential in the evaluation of patients with presumed or verified non-small cell lung cancer. For otolaryngologists, the strategy of routine cervical mediastinoscopy, performed under general anesthesia in the same procedure as bronchoscopy, is advocated as a standard approach to preoperative mediastinal assessment for the staging of non-small cell lung cancer.

Photoreactivity of biologically active compounds. VIII. Photosensitized polymerization of lens proteins by antimalarial drugs in vitro

The drugs commonly used in the treatment of malaria are photochemically unstable. Several of these compounds cause dermal and ocular toxic reactions that may be light induced. The in vitro photopolymerization of calf lens proteins in the presence of antimalarial drugs was studied as part of a screening of the photochemical properties and phototoxic capabilities of these compounds. The pseudo-first-order rate constant for the reaction was calculated, and related to the amount of light absorbed by the compounds in order to determine the relative photosensitizing effect of each drug. The reaction mechanisms were evaluated by adding a variety of quenchers to the reaction medium during irradiation. Based on the results obtained in this study and previous knowledge about the pharmacokinetic behavior of these compounds, several of the drugs investigated have to be considered as potential photosensitizers in the human lens, the retina and the skin.

Photoreactivity of biologically active compounds. VII. Interaction of antimalarial drugs with melanin in vitro as part of phototoxicity screening

The drugs commonly used in the treatment of malaria are photochemically unstable. Several of these compounds accumulate in melanin-rich tissues and cause toxic reactions which may be light induced. As part of the screening of the photochemical properties and phototoxic capabilities of antimalarials, the in vitro interaction of eight antimalarials with melanin was studied. The dissociation constant for the drug-melanin complex and the relative number of binding sites on melanin were estimated for six of the drugs using a curve-fitting program. The reaction rate for the formation of the melanin-drug complex was determined, and the complexes were further characterized by zeta potential measurements.

The effect of budesonide (Rhinocort) in the treatment of small and medium-sized nasal polyps

The objectives of this study were to determine if the size of nasal polyps could be assessed in a reproducible way and to study the effect of budesonide in patients suffering from eosinophilic nasal polyposis with small and medium sized polyps. Ninety-one patients entered the study. Budesonide 200 micrograms b.i.d. (aerosol or aqua) and placebo (aerosol or aqua) were compared in a 3-month double-blind, multi-centre, randomized study. Efficacy was measured by an assessment of polyp size, nasal peak-flow index and the patient's assessment of nasal symptoms. The conclusions were that the size of polyps could be assessed in a reproducible way, and that budesonide delivered either as a water-based suspension or as an aerosol is effective in the treatment of patients with small and medium sized polyps.

Spontaneous healing of traumatic tympanic membrane perforations in man: a century of experience

Widespread controversy exists concerning the treatment of traumatic tympanic membrane perforations. To elucidate the issue, a reference value for the rate of spontaneous tympanic membrane closure in man, to which the healing rates following different techniques of early surgical repair should be compared, was established on the basis of a review of more than 500 texts covering a century's literature on the traumatically perforated tympanic membrane. The spontaneous healing rate appeared to be close to 80 (78.7 per cent) in 760 evaluable cases of traumatic tympanic membrane perforations of all sorts diagnosed within 14 days post injury. A relative, causal-related variation of spontaneous healing could be demonstrated, and a pathogenetic classification of direct traumatic tympanic membrane perforations into ruptures induced by air-pressure changes, heat or corrosives, solids, and water pressures, is of proved clinical value and may have medico-legal validity. There is an obvious need for clinically controlled studies on the spontaneous healing of all kinds of traumatic perforations of the tympanic membrane in humans, and important elements in the design of future studies are advocated.

[Emphysematous pyelonephritis]

A case of emphysematous pyelonephritis (EPN) is described. EPN is a severe suppurative infection of the renal parenchyma and the perirenal tissue, characterized by intra-renal, and possibly perirenal, gas formation. This is a rare form of acute pyelonephritis. The condition is associated with a high mortality. Diabetic patients are particularly prone to the disease. The diagnosis is established with great certainty by computed tomography of the kidneys. The condition should be treated with an intensive combined medical-urological regimen with percutaneous nephrostomy guided by computed tomography or ultrasound should be performed. If no therapeutic response occurs, surgical incision and drainage or nephrectomy are recommended. In the present case of EPN, the medical treatment proved adequate.

Muscular hamartoma of the breast. A case report

A case of a muscular hamartoma of the breast in a 47-year-old woman is presented. Tumors containing smooth muscle are rare in the breast. Radiologically it appears as a circumscribed tumor with homogeneous or varying density. Histologically these lesions are composed of ducts, lobules, stroma prominently adipose, and smooth muscle.

Nasal packing and nocturnal oxygen desaturation

Nasal obstruction influences respiration during sleep, and nasal packing may be the cause of obstructive sleep apnoea. In order to investigate this phenomenon, perioperative nocturnal oxygen saturation was monitored for 3 nights with continuous, non-invasive pulse oximetry in 12 patients who had total nasal packs after septoplasty. Significant extension of nocturnal accumulated time of oxygen saturation less than 90% was demonstrated both during the first and second postoperative nights. The clinical significance of these results is as yet unknown, but the use of partial nasal packing in association with septoplasty is advocated and further investigations on nocturnal oxygen saturation are called for.

The peak flow nasal patency index

The peak flow nasal patency index (NPI) is the ratio between the nasal and oral peak airflow. This index was found to be a good indicator of nasal patency present in 24 patients following septoplasty and indicated significant improvement postoperatively. The peak flow nasal patency index was also correlated to self-assessment scores of nasal function in each patient. In this latter study, a low index correlated to a high self-assessment score, both of which indicated poor nasal patency. Our studies have shown that the peak flow nasal patency index is a useful measure for determining nasal patency, particularly for defining the results of any applied therapies.

[Malignant tracheal tumor--differential diagnosis in bronchial asthma]

Primary tumours of the trachea are rare and most of the symptoms relate to obstruction of the air passage leading to inspiratory and expiratory stridor. Unfortunately, the inclusion of malignant tracheal neoplasms in the differential diagnosis of onset of wheeze in adults is even more rare than the tumours themselves. We report a case where a tracheal adenoid cystic carcinoma presented symptoms suggestive of bronchial asthma. It is emphasized that delay by the physician in diagnosing tracheal tumours is the principal problem, and that adult patients who experience onset of stridor and dyspnoe and do not respond to accepted medical treatment deserve systematic radiographic and endoscopic evaluation of the entire air passage.

Episodic nocturnal hypoxia and nasal packs

Nasal obstruction influences respiration during sleep and nasal packs may cause obstructive sleep apnoea. In order to investigate this, the perioperative oxygen saturation was monitored for 3 nights with continuous pulse oximetry in 12 patients, who had bilateral nasal packs after septoplasty. A significant increase in the number of nocturnal episodes of hypoxia and a significant prolongation of the mean duration of the individual hypoxic periods were demonstrated during the first and the second post-operative nights. The clinical significance of these results is as yet unknown, but the use of partial nasal packing in septoplasty is advocated. Further investigations of nocturnal oxygen desaturation and design of nasal packs, securing the post-operative nasal airway, are needed.