Harnessing the potential of fatty Acid-Surfactant-Based micellar gel for enhanced topical delivery of Apremilast in psoriasis treatment

Apremilast (APR) is a potent anti-psoriatic agent that inhibits the phosphodiesterase 4 enzyme. Due to the poor oral bioavailability and associated systemic side effects the clinical applicability of APR has been constrained. Nanotechnology-based carrier system presents a novel option to increase the efficacy of the topical treatment of APR. The current investigation deals with the development of fatty acid-surfactant conjugate-based hybrid mixed micellar gel (HMMG) for the topical delivery of APR. The developed micelles exhibited an average size of 83.59 ± 4.46 nm, PDI of 0.239 ± 0.047, % entrapment efficiency of ∼ 94.78 ± 3.98 %, with % practical drug loading of ∼11.37 ± 3.14 %. TEM analysis revealed the spherical shape of micelles. The hybrid micelles were further loaded in a carbopol®934P gel base for ease of application. Ex vivo permeation study revealed enhanced permeation and ∼ 38-fold higher retention in deeper layers of skin from a hybrid micellar gel. In vivo, assessment demonstrated augmented efficacy of APR-HMMG as compared to 0.1 % betamethasone valerate. Also, APR-HMMG showed no sign of irritation, suggesting superior safety as a topical application. Thus, the proposed formulation strategy represents a viable avenue for enhancing the therapeutic efficacy of various anti-psoriatic moieties.

Intranasal Drug Delivery by Nanotechnology: Advances in and Challenges for Alzheimer's Disease Management

Alzheimer's disease, a progressive neurodegenerative condition, is characterized by a gradual decline in cognitive functions. Current treatment approaches primarily involve the administration of medications through oral, parenteral, and transdermal routes, aiming to improve cognitive function and alleviate symptoms. However, these treatments face limitations, such as low bioavailability and inadequate permeation. Alternative invasive methods, while explored, often entail discomfort and require specialized assistance. Therefore, the development of a non-invasive and efficient delivery system is crucial. Intranasal delivery has emerged as a potential solution, although it is constrained by the unique conditions of the nasal cavity. An innovative approach involves the use of nano-carriers based on nanotechnology for intranasal delivery. This strategy has the potential to overcome current limitations by providing enhanced bioavailability, improved permeation, effective traversal of the blood-brain barrier, extended retention within the body, and precise targeting of the brain. The comprehensive review focuses on the advancements in designing various types of nano-carriers, including polymeric nanoparticles, metal nanoparticles, lipid nanoparticles, liposomes, nanoemulsions, Quantum dots, and dendrimers. These nano-carriers are specifically tailored for the intranasal delivery of therapeutic agents aimed at combatting Alzheimer's disease. In summary, the development and utilization of intranasal delivery systems based on nanotechnology show significant potential in surmounting the constraints of current Alzheimer's disease treatment strategies. Nevertheless, it is essential to acknowledge regulatory as well as toxicity concerns associated with this route; meticulous consideration is required when engineering a carrier. This comprehensive review underscores the potential to revolutionize Alzheimer's disease management and highlights the importance of addressing regulatory considerations for safe and effective implementations. Embracing this strategy could lead to substantial advancements in the field of Alzheimer's disease treatment.

Variability in the presentation of complicated jejunal diverticulosis

Jejunal diverticulosis is a rare disease which normally presents for the first time with acute complications, often requiring surgical intervention. The diverticulae are acquired, occurring more commonly after middle age, but their aetiology is unclear. We discuss this condition in the context of four cases which presented to our hospital as emergencies over a five year period: small bowel obstruction, gastrointestinal haemorrhage, small bowel volvulus, and visceral perforation. Our aim is to encourage clinicians to include jejunal diverticular disease as a differential diagnosis in patients with abdominal symptoms.

Perfusion CT to assess angiogenesis in colon cancer: technical limitations and practical challenges

OBJECTIVE

Perfusion CT may have the potential to quantify the degree of angiogenesis of solid tumours in vivo. This study aims to identify the practical and technical challenges inherent to the technique, and evaluate its feasibility in colorectal tumours.

METHODS

51 patients from 2 institutions prospectively underwent a single perfusion CT on 2 different multidetector scanners. The patients were advised to breath-hold as long as possible, followed by shallow breathing, and were given intravenous buscopan to reduce movement. Numerous steps were explored to identify the challenges.

RESULTS

43 patients successfully completed the perfusion CT as per protocol. Inability to detect the tumour (n=3), misplacement of dynamic sequence co-ordinates (n=2), failure of contrast injection (n=2) and displacement of tumour (n=1) were the reasons for failure. In 14 cases excessive respiratory motion displaced the tumour out of the scanning field along the temporal sequence, leading to erroneous data capture. In nine patients, minor displacements of the tumour were corrected by repositioning the region of interest (ROI) to its original position after reviewing each dynamic sequence slice. In 20 patients the tumour was stable, and data captured from the ROI were representative, and could have been analysed by commercially available Body Tumor Perfusion 3.0® software (GE Healthcare, Waukesha, WI). Hence all data were manually analysed by MATLAB® processing software (MathWorks, Cambridge, UK).

CONCLUSION

Perfusion CT in tumours susceptible to motion during acquisition makes accurate data capture challenging and requires meticulous attention to detail. Motion correction software is essential if perfusion CT is to be used routinely in colorectal cancer.

Anti-C1q antibodies and their association with complement components in Indian systemic lupus erythematosus patients

Systemic lupus erythematosus (SLE) is a prototype autoimmune disease, characterized by immune complex formation and systemic inflammation. Complement components such as C1q and mannose-binding lectin (MBL) play an important role in the clearance of immune complexes. Anti-C1q antibodies are associated with lupus nephritis and reduced levels of the complement components. The objective of this study was to detect anti-C1q antibodies in SLE patients and to evaluate their association with the complement components. Sixty SLE patients were included, of whom 75% had lupus nephritis (LN) and 25% were without renal manifestations (non-LN). The disease activity was assessed at the time of evaluation by the systemic lupus erythematosus disease activity index (SLEDAI). Anti-C1q antibodies, circulating immune complexes, and serum MBL levels were detected by enzyme-linked immunosorbent assay. The anti-C1q antibody prevalence was 58.3%. The LN patients showed 60% anti-C1q positivity with a higher percentage in membranoproliferative glomerulonephritis patients (51.9%). Anti-dsDNA positivity was slightly higher among the anti-C1q positives than in the anti-C1q negatives (65.7% vs. 60%). A higher percentage of reduced C3 and C4 levels was noted among the anti-C1q positives. The LN patients showed a higher percentage of low MBL levels among anti-C1q negatives than in the anti-C1q positives (61.1% vs. 55.6%). Non-LN patients showed a higher percentage of low MBL levels among anti-C1q positives than among anti-C1q negatives (87.5% vs. 57.1%). Anti-C1q antibodies were found in both LN and non-LN patients, but there was no correlation with the clinical severity of the disease.

Accuracy of radiological staging in identifying high-risk colon cancer patients suitable for neoadjuvant chemotherapy: a multicentre experience

AIM

A pilot study was undertaken to determine the accuracy of computed tomography (CT) staging in identifying patients with high-risk colon cancers who would be considered as candidates for a neoadjuvant therapy trial (FOxTROT) and those at low risk (T1/T2) who would be excluded.

METHOD

Participating radiologists from 19 centres attended workshops for standardization of image interpretation according to previously defined prognostic criteria: good prognosis tumours, including, T1/T2; intermediate prognosis, T3 < 5 mm tumour invasion beyond the muscularis propria (MP); and poor prognosis tumours, including T3 with tumour extension ≥ 5 mm beyond the MP or T4. The CT findings were compared with histopathology as the reference standard.

RESULTS

Of 94 patients with radiological and pathological data, 71% were categorized by CT as having a poor prognosis. The sensitivity and specificity of CT in identifying these tumours were 87% (95% CI, 74-94) and 49% (95% CI, 33-65). Sensitivity and specificity for tumour infiltration beyond the MP (T3/T4 vs T1/T2) were 95% (95% CI, 87-98) and 50% (95% CI, 22-77), respectively. Including all CT-staged T3 and T4 patients in the trial would have increased the proportion eligible for entry to 89% (n = 84) without affecting the false-positive rate of 7%. Some 20% of T3/T4 patients would have been ineligible for FOxTROT because of synchronous metastases.

CONCLUSION

In a multicentre setting, CT scanning identified high-risk (T3/4) colon cancers with minimal overstaging of T1/T2 tumours, thus establishing the feasibility of radiologically guided neoadjuvant chemotherapy.

Accuracy of multidetector computed tomography in identifying poor prognostic factors in colonic cancer

BACKGROUND

Recent neoadjuvant strategies for high-risk colonic tumours have renewed interest in accurate preoperative staging. The aim of this study was to validate prospectively the accuracy of multidetector computed tomography (MDCT) in stratifying patients into good and poor prognostic groups in a multicentre setting.

METHODS

Staging MDCT scans of 84 patients with colonic cancer were reviewed by two independent radiologists and stratified into low-risk (T1/T2 and T3 with extramural tumour depth (EMD) of less than 5 mm) and high-risk (T3 with EMD of at least 5 mm and T4) tumours. Nodal status and extramural venous invasion (EMVI) were also assessed.

RESULTS

The accuracy, sensitivity, specificity and positive predictive value of stratification by CT compared with histological examination was 74 (95 per cent confidence interval 64 to 82), 78 (65 to 87), 67 (49 to 81) and 81 (68 to 89) per cent respectively. Accuracy for detecting malignant lymph nodes and EMVI was 58 and 70 per cent respectively. The agreement for predicting prognostic stratification was moderate (kappa = 0.54).

CONCLUSION

As the ability of CT to identify node status is poor, the depth of tumour invasion beyond the muscularis propria is the most accurate way to identify patients with a poor prognosis who may be suitable for neoadjuvant treatment.

CT staging of colon cancer

Computer tomography (CT) has been the principal investigation in the staging of colon cancers. The information obtained with routine CT has been limited to identifying the site of the tumour, size of the tumour, infiltration into surrounding structures and metastatic spread. The Foxtrot trial National Cancer Research Institute (NCRI) has been specifically designed to evaluate the efficacy of neoadjuvant treatment in colon cancers by using preoperative chemotherapy with or without an anti-Epidermal Growth Factor Receptor (EGFR) monoclonal antibody to improve outcome in high-risk operable colon cancer. Patients are selected based on their staging CT examination. The criteria for poor prognosis are T4 and T3 tumours with more than 5mm extramural depth. Thus the success of the trial would depend upon the confidence of the radiologist to identify the patients that would receive the neoadjuvant treatment. The aim of this review is to explain the process of identifying high-risk features seen on the staging CT images. This will help to identify a cohort of patients that could truly benefit from neoadjuvant strategies.

Ruptured superficial femoral artery aneurysm treated by simple ligation

A 79-year-old man, with a background of peripheral vascular disease, presented to the emergency department with a sudden increase in the size of his swelling in the right thigh, indicating rupture of his right superficial femoral artery aneurysm. His past medical history included having had a left femoropopliteal bypass (1986), abdominal aortic aneurysm repair (1991), repair of false aneurysm on the right (1992) and repair of left common femoral artery aneurysm (1995). On surgical exploration, four contiguous aneurysms in the right superficial femoral artery were identified, which measured around 25 cm in total length. After achieving control of the aneurysm, it was noted that the popliteal artery was unsuitable for anastomosis. However, the leg was still adequately perfused via collaterals in spite of the ligation, so nothing further was done. The patient was put on a heparin infusion postoperation, and had an uneventful recovery with a viable limb on discharge. It is a useful reminder that ligation can still be an option in vascular emergencies in some situations.

Cytomegalovirus oesophagitis in a patient with Non-Hodgkin's lymphoma

Cytomegalovirus (CMV) infection is frequent in immunocompromised patients, especially in AIDS, organ transplantation and rarely in Hodgkin's disease and Non-Hodgkin's lymphoma (NHL). We present a case of NHL with CMV oesophagitis, which has rarely been documented in literature. Apart from fungal and herpes simplex infections, as the common differential diagnosis for oesophagitis in patients of lymphoma, CMV should be considered an important etiologic agent. Early diagnosis and prompt treatment of CMV oesophagitis with gancyclovir can avert significant morbidity and avoid unacceptable treatment delays.

Preoperative chemotherapy and the outcome of liver resection for colorectal metastases

BACKGROUND

Neoadjuvant systemic chemotherapy is being increasingly used prior to liver resection for colorectal metastases. Oxaliplatin has been implicated in causing structural changes to the liver parenchyma, and such changes may increase the morbidity and mortality of surgery.

PATIENTS AND METHODS

A retrospective study was undertaken of 101 consecutive patients who had undergone liver resection for colorectal metastases in two HPB centers. Preoperative demographic and premorbid data were gathered along with liver function tests and tumor markers. A subjective assessment of the surgical procedure was noted, and in-hospital morbidity and mortality were calculated. The effect of preoperative chemotherapy on short-term and long-term outcome was analyzed, and actuarial 1 and 3 year survival was determined.

RESULTS

Patients who received neoadjuvant chemotherapy had a higher number of metastases (median 2, range 1-8 versus median 1, range 1-5; P = 0.019) and more had synchronous tumors (24 patients versus 8; P < 0.001). Overall morbidity was 37% and hospital mortality was 3.9%. Operative and in-hospital outcome was not influenced by chemotherapy. Long-term survival was worse in patients who had received preoperative chemotherapy (actuarial 3-year survival 62% versus 80%; P = 0.04).

CONCLUSIONS

This study shows no evidence that neoadjuvant chemotherapy, and in particular oxaliplatin, increases the risk associated with liver resection for colorectal metastases. Long-term outcome is reduced in patients receiving preoperative chemotherapy, although they have more advanced disease.

Invasive adenocarcinoma of the vagina following surgery for adenocarcinoma in situ of the cervix--recurrence or implantation?

A 51-year-old woman underwent cervical conization for severe glandular abnormal cells. Histology noted adenocarcinoma in situ (AIS) with incomplete excision margins. Four months later, hysterectomy revealed no residual disease. Six months subsequently she developed invasive adenocarcinoma of the upper vagina. This report documents the unusual behavior of AIS and its management difficulties.

Influence of higher rates of agitation on release patterns of immediate-release drug products

The dissolution procedure serves as a quality control test to assure batch-to-batch uniformity and bioequivalence of a product once the bioavailability of the product has been established. It can also be used to detect manufacturing and/or process variations that could reduce product bioavailability. Dissolution testing must be conducted at an appropriate agitation rate. Tests conducted at high agitation rates may lose the ability to differentiate between good and bad products. Although the effect of high agitation rates has been known for some time, several immediate-release drug products still have United States Pharmacopeia (USP) monograph dissolution procedures that require very high agitation rates. A systematic survey was conducted on marketed tablets of chloroquine phosphate, griseofulvin, hydroxychloroquine sulfate, isocarboxazide, primaquine phosphate, and sulfadiazine. Each of these products has a USP monograph requiring a dissolution test at a paddle speed of 100 rpm. To study the influence of agitation rate on the dissolution rate of these products, dissolution studies were conducted at paddle speeds of 50, 75, and 100 rpm with the USP apparatus 2 (paddle method). The dissolution rate increased with an increase in the agitation rate from 50 to 75 rpm. However, no significant increase in the dissolution rate was noted with an increase in the agitation rate from 75 to 100 rpm. The data support the position that the higher agitation rate of 100 rpm is not necessary for a quality control procedure or a compendial standard for the products tested.

Analytical methods validation: bioavailability, bioequivalence and pharmacokinetic studies. Conference report

This is a summary report of the conference on Analytical Methods Validation: Bioavailability, Bioequivalence and Pharmacokinetic Studies. The conference was held from December 3 to 5, 1990 in the Washington, DC area and was sponsored by the American Association of Pharmaceutical Scientists, US Food and Drug Administration, Federation International Pharmaceutique, Health Protection Branch (Canada) and Association of Official Analytical Chemists. The purpose of the report is to represent our assessment of the major agreements and issues discussed at the conference. The report is also intended to provide guiding principles for validation of analytical methods employed in bioavailability, bioequivalence and pharmacokinetic studies in man and animals. The objectives of the conference were: 1. To reach a consensus on what should be required in analytical methods validation and the procedures to establish validation; 2. To determine processes of application of the validation procedures in the bioavailability, bioequivalence and pharmacokinetic studies; 3. To develop a report on analytical methods validation (which may be referred to in developing future formal guidelines). Acceptable standards for documenting and validating analytical methods with regard to processes, parameters or data treatments were discussed because of their importance in assessment of pharmacokinetic, bioavailability and bioequivalence studies. Other topics which were considered essential in the conduct of pharmacokinetic studies or in establishing bioequivalency criteria, including measurement of drug metabolites and stereoselective determinations, were also deliberated.

Correlation of in vivo bioavailability of erythromycin stearate tablets with in vitro tests

Correlations between the bioavailability parameters for erythromycin stearate tablets from five manufacturers and in vitro tests of these tablets were examined using forward (stepwise), multiple linear regression analysis. Bioavailability parameters were determined in clinical studies employing a balanced, incomplete block design. In vitro tests used disintegration, dissolution, and dissolution/dialysis as the independent variables in regression equations. Significant correlations were found between linear combinations of these parameters and the time of peak and the peak serum levels. The inclusion of an in vitro disintegration test to describe peak serum levels of erythromycin is noteworthy since it has been suggested that disintegration tests are of less value than dissolution techniques employed in the present investigation may be useful for selection of appropriate physicochemical tests for continued monitoring of the bioavailability of erythromycin stearate tablets.

Bioavailability of imipramine tablets relative to a stable isotope-labeled internal standard: increasing the power of bioavailability tests

A new methodology for comparative bioavailability testing is described in which each drug formulation is compared with a stable isotope-labeled variant of the drug that is consumed orally in solution at the same time the tested formulation is ingested. The methodology is used to determine the comparative bioavailabilities of two commercially available brands of imipramine hydrochloride. The power of the new methodology to detect differences between drug formulations, when, in fact, such differences exist, is shown to be superior to that of conventional bioavailability tests.

The effect of keto-analogues of essential amino acids in severe chronic uremia

Alpha keto-analogues of valine, leucine, isoleucine, methionine, phenylalanine, and (in one instance) tryptophan and histidine, along with the remaining essential amino acids, were administered orally to 10 patients with severe chronic uremia fed a diet low in protein but adequate in calories. Ketoacid dosage varied from 6 to 14 g daily, as sodium or calcium salts. Net nitrogen intake, calculated as intake minus urinary protein nitrogen, averaged 1.8 g/day. The urea space was either estimated or measured with [(14)C]urea and daily changes in the body urea pool were calculated. Urea appearance was measured as the sum of urea excretion and the change in urea pool. If these ketoacids were converted to amino acids and utilized for protein synthesis, a fall in urea nitrogen appearance should occur. In five subjects, ketoacids were given for 15-18 days and then withdrawn. Urea nitrogen appearance increased 1.55 g/day on withdrawing ketoacids, and corrected nitrogen balance decreased by 1.73 g/day. In two other subjects ketoacid administration was followed, on two occasions each, by a period of administration of nine essential amino acids. In three of these four instances, urea appearance rose significantly with amino acids. In four patients studied at high blood urea levels, ketoacid treatment was relatively ineffective; two of these patients responded more favorably when studied again after peritoneal dialysis. One of these improved enough clinically to be managed as an out-patient for short intervals, despite virtual anuria. No accumulation of ketoacids in plasma or urine could be detected, and no toxicity was identified.