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1.
Dermatol Surg ; 48(12): 1274-1278, 2022 12 01.
Article in English | MEDLINE | ID: mdl-36449867

ABSTRACT

BACKGROUND: Postoperative auricular defects heal well with secondary intention healing (SIH); however, potential complications include postoperative pain, perichondritis, and chondritis. OBJECTIVE: To compare postoperative pain and wound healing in auricular defects healing by secondary intention with and without the placement of a porcine xenograft. MATERIALS AND METHODS: Twenty-one subjects were enrolled in the study. The primary outcome was self-reported pain, measured on a 0 to 10 scale for 14 postprocedure days. Secondary outcomes included time to greater than 90% of reepithelialization and degree of wound contraction. RESULTS: There was a 1 to 2 point difference in median pain scores between the porcine graft and control groups during postoperative days 4 to 7, 12, and 13. Time to 90% or greater reepithelialization was not statistically different between groups (p = .94). The average wound contraction was 34.1% for the porcine group and 34.0% for the control group (p = .95). CONCLUSION: In this pilot study, overall pain scores were low in both groups. Placement of a porcine xenograft resulted in a slight reduction of median pain compared with traditional SIH. Patients in the control group were more likely to require analgesics. Similar rates of reepithelialization and degree of wound contracture were observed.


Subject(s)
Cartilage Diseases , Wound Healing , Humans , Swine , Animals , Pilot Projects , Heterografts , Pain Measurement , Pain, Postoperative/etiology
2.
AAPS PharmSciTech ; 21(2): 67, 2020 Jan 14.
Article in English | MEDLINE | ID: mdl-31938980

ABSTRACT

Onychomycosis is a chronic disorder that is difficult to manage and hard to eradicate with perilous trends to relapse. Due to increased prevalence of HIV, use of immunosuppressant drugs and lifestyle-related factors, population affected with fungal infection of nail (Onychomycosis) happens to increase extensively in last two decades. Modalities available for the treatment of onychomycosis include systemically administered antifungals, mechanical procedures, and topical drug therapy. But the efficacy of the most of approaches to deliver drug at targeted site, i.e., deep-seated infected nail bed is limited due to compact and highly keratinized nail structure. A series of advanced formulation approaches, such as transfersomes, liposomes, nano/micro emulsion, nail lacquers etc., have been attempted to improve the drug penetration into nail plate more efficiently. The manuscript reviews these formulation approaches with their possible mechanisms by which they improve the drug penetration.Comparative analysis of available treatment modalities for onychomycosis has been provided with pros and cons of each alternatives. Additionally, ongoing research about the application of biological materials such as modified cationic antimicrobial peptides (AMPs), plant-derived proteins, and synthetic antimicrobial peptidomimetics have also been explored.


Subject(s)
Antifungal Agents/therapeutic use , Onychomycosis/drug therapy , Administration, Cutaneous , Administration, Topical , Antifungal Agents/administration & dosage , Drug Compounding , Drug Delivery Systems , Humans , Onychomycosis/microbiology
3.
Drug Dev Ind Pharm ; 44(12): 1933-1941, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30102080

ABSTRACT

Precipitation inhibitory potential of polymers screened from precipitation study may be altered once it is formulated in amorphous solid dispersions (ASDs). OBJECTIVE: Present study was embarked with an objective to determine whether the polymers retain the same inhibitory potential after formulating them into ASDs. METHODS: Screening of polymers was based on a new dimensionless parameter 'Supersaturation Holding Capacity (SHC)' calculated from the precipitation study. Nifedipine ASDs were formulated using HPMC E3 and HPMC E50 (high SHC values), and HPMC K100M, PVP K25, and HPC M (low to moderate SHC values). Generated ASDs were characterized by DSC, FTIR, and PXRD and evaluated for stability under accelerated conditions (40˚C and 75% RH) for 6 months. RESULTS: Thermal analysis of the ASDs and theoretical prediction of the glass transition temperature (Tg) suggested a linear dependency of Tg on the content of HPMC E3 and HPMC E50. Under accelerated stability conditions, all ASDs of nifedipine with HPMC E3 and HPMC E50 (except ASDs with 70% drug load) were stable, which could be attributed to the molecular level dispersion of the drug in these polymers. SHC parameter calculated from the apparent solubility profile gave following rank order HPMC E50 (3.4) > HPMC E3 (3.2) > HPMC K100M (1.29) > PVP K25 (1.09) > HPC M (0.99). SHC calculated from the apparent solubility profile of ASDs demonstrated good agreement between the solution state and solid state screening of the polymers for precipitation inhibition. During dissolution study, nearly four-fold enhancement has been observed with ASDs comprising HPMC E3 and HPMC E50. CONCLUSIONS: The outcome of the study concluded that SHC can be a promising parameter in the screening of polymers for the development of the ASDs.


Subject(s)
Drug Carriers/chemistry , Drug Compounding/methods , Drug Liberation , Polymers/chemistry , Chemical Precipitation , Chemistry, Pharmaceutical , Crystallization , Nifedipine/administration & dosage , Nifedipine/chemistry , Solubility , Transition Temperature
4.
Am J Dermatopathol ; 39(4): 300-303, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27805920

ABSTRACT

Benign glandular schwannomas are rare and should be distinguished from malignant peripheral nerve sheath tumors with similar divergent tissue differentiation. The authors present a benign glandular schwannoma with ancient change that developed in the subcutis of a 46-year-old man's posterior calf. He lacked stigmata of neurofibromatosis type 1 (NF1). The glandular elements stained positively for epithelial membrane antigen and pancytokeratin. The spindled cells stained positively for SOX10 and S100 protein, supporting schwannian (neural crest) differentiation. The tumor's location and histopathology suggest that the pathogenesis stems from entrapment of sweat glands. Finally, it must be recognized that ancient change may mimic malignancy in these neoplasms as the malignant counterparts have a greater association with NF1 and a poorer prognosis.


Subject(s)
Neurilemmoma/pathology , Soft Tissue Neoplasms/pathology , Biomarkers, Tumor/analysis , Humans , Immunohistochemistry , Leg/pathology , Male , Middle Aged
5.
Am J Dermatopathol ; 38(12): 927-929, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27828803

ABSTRACT

Cutaneous meningiomas (CM) are a small subset of meningiomas, further classified into three subtypes. The authors present a 15-year-old male with a symptomatic congenital type I CM and describe the histopathological and immunohistochemical findings. To the authors' knowledge, this is the first report of an extraspinal lumbar type I CM with intradural attachment to the phylum terminale.


Subject(s)
Dura Mater/pathology , Meningioma/pathology , Meningocele/pathology , Skin Neoplasms/pathology , Adolescent , Biomarkers, Tumor/analysis , Biopsy , Dura Mater/chemistry , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Male , Meningioma/chemistry , Skin Neoplasms/chemistry
6.
J Cutan Pathol ; 42(1): 39-45, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25393781

ABSTRACT

BACKGROUND: Complications from graft-vs.-host disease (GVHD), a major contributor to morbidity and mortality following hematopoietic cell transplantation, may be mitigated by early diagnosis and intervention. However, differentiation between acute cutaneous GVHD and other common skin eruptions that develop in the post-transplantation period, such as drug hypersensitivity reaction, can be challenging clinically and microscopically. Because recent evidence indicates that CD123, a marker of plasmacytoid dendritic cells, can help to distinguish gastrointestinal GVHD from the clinicopathologic mimic cytomegalovirus colitis, we aimed to determine whether CD123 could aid in the diagnosis of acute cutaneous GVHD. METHODS: We studied 12 skin specimens of patients with grades I-II cutaneous GVHD and 12 from patients who had drug hypersensitivity reaction with vacuolar interface changes on biopsy. RESULTS: No differences were seen between the two groups with regards to density or distribution of CD123 expression. Specimens representing GVHD showed significantly less spongiosis (P < 0.001) and fewer dermal eosinophils (P = 0.03) compared to those representing drug hypersensitivity reaction. CONCLUSIONS: We conclude that CD123 does not appear to be a useful ancillary test in the diagnosis of acute cutaneous GVHD. Careful correlation between clinical findings and features with microscopy remains the cornerstone of accurate diagnosis of acute cutaneous GVHD.


Subject(s)
Drug Hypersensitivity/pathology , Graft vs Host Disease/pathology , Biopsy , CD4 Antigens/metabolism , Colitis/diagnosis , Colitis/pathology , Colitis/virology , Cytomegalovirus Infections/diagnosis , Cytomegalovirus Infections/metabolism , Cytomegalovirus Infections/pathology , Dendritic Cells/pathology , Diagnosis, Differential , Drug Hypersensitivity/diagnosis , Drug Hypersensitivity/metabolism , Forkhead Transcription Factors/metabolism , Graft vs Host Disease/diagnosis , Graft vs Host Disease/metabolism , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunohistochemistry , Interleukin-3 Receptor alpha Subunit/metabolism , Peptide Fragments/metabolism , Skin/pathology
7.
Dermatol Surg ; 41(2): 201-8, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25627628

ABSTRACT

BACKGROUND: Primary mucinous carcinoma of the skin (PMCS) is a rare adnexal eccrine sweat gland neoplasm, often mistaken for metastasis from extracutaneous sites or misdiagnosed. Primary mucinous carcinoma of the skin is a slow-growing tumor with a high recurrence rate after conventional excision. OBJECTIVE: To describe clinicopathologic features, rate of recurrence, and metastasis and to review relevant literature. MATERIALS AND METHODS: The authors identified patients with PMCS treated from January 1992 through December 2012 at Mayo Clinic. The authors retrospectively reviewed medical records and histology slides. Relevant publications were identified through Ovid MEDLINE and PubMed. RESULTS: Six patients with PMCS were identified (1 male). The average age at diagnosis was 63 years. Tumor size ranged from 0.5 to 2.0 cm, and all were confined within the dermis. No evidence of metastatic mucinous adenocarcinoma was documented at the time of diagnosis. Five patients underwent Mohs micrographic surgery, and 1 was treated with wide local excision. There were no episodes of recurrence or metastases after a median follow-up of 20 months (range, 0.5-207 months). CONCLUSION: Mohs micrographic surgery may offer reduced recurrence rates and better outcomes in PMCS. Further studies with longer follow-up and bigger cohorts of patients with PMCS are warranted.


Subject(s)
Adenocarcinoma, Mucinous/pathology , Skin Neoplasms/pathology , Adenocarcinoma, Mucinous/surgery , Aged , Aged, 80 and over , Diagnosis, Differential , Facial Neoplasms/pathology , Facial Neoplasms/surgery , Female , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/surgery , Humans , Male , Middle Aged , Mohs Surgery , Neoplasm Recurrence, Local/prevention & control , Retrospective Studies , Scalp/pathology , Scalp/surgery , Skin Neoplasms/surgery , Thoracic Wall/pathology , Thoracic Wall/surgery
8.
J Am Acad Dermatol ; 70(6): 1021-7, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24636890

ABSTRACT

BACKGROUND: In patients with malignancy-associated Sweet syndrome, a thorough evaluation for leukemia cutis should be considered. OBJECTIVE: We sought to describe the clinicopathologic characteristics of histiocytoid Sweet syndrome. METHODS: We retrospectively identified patients with histiocytoid Sweet syndrome at our institution from January 1992 through December 2010. We evaluated the underlying cutaneous infiltrate using immunohistochemistry and fluorescence in situ hybridization. RESULTS: We re-evaluated all 22 patients with hematologic malignancy-associated Sweet syndrome. Six patients had a monocytoid infiltrate that was consistent with histiocytoid Sweet syndrome; subsequent evaluation of these patients demonstrated cytogenetic abnormalities on prior bone-marrow biopsy specimens. Fluorescence in situ hybridization analysis was feasible in cutaneous specimens from 5 of the 6 patients and demonstrated the same cytogenetic abnormalities that were identified on prior bone-marrow biopsy specimens in 4 patients. Therefore, these 4 patients may have had a form of leukemia cutis. LIMITATIONS: This was a retrospective study. CONCLUSION: For patients with histiocytoid Sweet syndrome, an underlying hematologic malignancy, and a monocytoid infiltrate on biopsy specimen, fluorescence in situ hybridization of the cutaneous infiltrate may be beneficial to identify cytogenetic abnormalities that may indicate leukemia cutis.


Subject(s)
Histiocytes/pathology , In Situ Hybridization, Fluorescence/methods , Leukemia/diagnosis , Skin Neoplasms/diagnosis , Sweet Syndrome/diagnosis , Aged , Aged, 80 and over , Biopsy, Needle , Chromosome Aberrations , Cohort Studies , Comorbidity , Female , Follow-Up Studies , Humans , Immunohistochemistry , Incidence , Leukemia/epidemiology , Male , Middle Aged , Retrospective Studies , Risk Assessment , Skin Neoplasms/epidemiology , Sweet Syndrome/epidemiology
9.
J Am Acad Dermatol ; 69(4): 557-64, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23891394

ABSTRACT

BACKGROUND: Sweet syndrome is a neutrophilic dermatosis with cutaneous tender lesions that can be associated with malignancies, infections, systemic inflammatory disorders, and medications. Although numerous studies have described Sweet syndrome, few studies have systematically investigated Sweet syndrome. OBJECTIVE: We sought to describe characteristics and treatments of patients with Sweet syndrome and evaluate clinical differences depending on the underlying cause. METHODS: A retrospective study was conducted to identify patients with Sweet syndrome evaluated at Mayo Clinic from 1992 to 2010. RESULTS: Of 77 patients with Sweet syndrome (mean age of onset 57 years), 43 (56%) were male. Eighteen patients (23%) reported a preceding infection. A total of 41 (53%) patients were classified as having classic Sweet syndrome, 27 (35%) patients had malignancy-associated Sweet syndrome, and in 9 (12%) patients drug-induced Sweet syndrome was considered. In all, 21 patients had a hematologic malignancy or myeloproliferative/myelodysplastic disorder, whereas 6 patients had solid tumors. The mean hemoglobin level, in both male and female patients (P < .0443 and P < .0035, respectively), was significantly lower in malignancy-associated versus classic and drug-induced Sweet syndrome. Systemic corticosteroids were the most frequently used treatment (70%). LIMITATIONS: This is a retrospective study and represents patients from a single academic center. CONCLUSIONS: Sweet syndrome is a distinctive disorder with certain clinical and histologic characteristics, which usually has a complete response to systemic corticosteroids. It is important to evaluate Sweet syndrome patients who have laboratory evidence of anemia for an underlying malignancy.


Subject(s)
Drug-Related Side Effects and Adverse Reactions/epidemiology , Neoplasms/epidemiology , Sweet Syndrome/drug therapy , Sweet Syndrome/epidemiology , Academic Medical Centers , Adjuvants, Immunologic/therapeutic use , Adrenal Cortex Hormones/therapeutic use , Adult , Age Factors , Age of Onset , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Antineoplastic Agents/therapeutic use , Cohort Studies , Comorbidity , Dermatologic Agents/therapeutic use , Drug Therapy, Combination , Female , Humans , Incidence , Male , Middle Aged , Neoplasms/pathology , Retrospective Studies , Risk Assessment , Severity of Illness Index , Sex Factors , Sweet Syndrome/etiology , Sweet Syndrome/physiopathology , Treatment Outcome
10.
Nat Med ; 11(7): 731-9, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15980865

ABSTRACT

The Poxviridae family members vaccinia and variola virus enter mammalian cells, replicate outside the nucleus and produce virions that travel to the cell surface along microtubules, fuse with the plasma membrane and egress from infected cells toward apposing cells on actin-filled membranous protrusions. We show that cell-associated enveloped virions (CEV) use Abl- and Src-family tyrosine kinases for actin motility, and that these kinases act in a redundant fashion, perhaps permitting motility in a greater range of cell types. Additionally, release of CEV from the cell requires Abl- but not Src-family tyrosine kinases, and is blocked by STI-571 (Gleevec), an Abl-family kinase inhibitor used to treat chronic myelogenous leukemia in humans. Finally, we show that STI-571 reduces viral dissemination by five orders of magnitude and promotes survival in infected mice, suggesting possible use for this drug in treating smallpox or complications associated with vaccination. This therapeutic approach may prove generally efficacious in treating microbial infections that rely on host tyrosine kinases, and, because the drug targets host but not viral molecules, this strategy is much less likely to engender resistance compared to conventional antimicrobial therapies.


Subject(s)
Piperazines/pharmacology , Poxviridae/pathogenicity , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-abl/antagonists & inhibitors , Pyrimidines/pharmacology , Actins/antagonists & inhibitors , Actins/metabolism , Animals , Benzamides , Cells, Cultured , Female , Imatinib Mesylate , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Poxviridae/drug effects , Poxviridae Infections/drug therapy , Proto-Oncogene Proteins c-abl/metabolism , Pyridines/pharmacology , Survival Rate , Vaccinia/drug therapy , Vaccinia/mortality , Vaccinia virus/metabolism , Virion/drug effects , Virion/metabolism , src-Family Kinases/antagonists & inhibitors , src-Family Kinases/metabolism
11.
Dermatol Ther ; 24(2): 219-28, 2011.
Article in English | MEDLINE | ID: mdl-21410611

ABSTRACT

The treatment of cutaneous graft-versus-host disease (GVHD) is one of the most challenging clinical scenarios in a dermatological practice. Given the significant risk of morbidity and mortality in this patient group, it is important for a dermatologist to understand the pathophysiology of GVHD, as well as their role within a multidisciplinary practice where many immunosuppressants are prescribed. A significant proportion of the patients with GVHD will require a combination treatment regimen in order to stem the progression of their disease. In this review, the stages, type of GVHD and treatment options are reviewed for the dermatologist.


Subject(s)
Graft vs Host Disease/therapy , Skin Diseases/therapy , Acute Disease , Chronic Disease , Graft vs Host Disease/classification , Graft vs Host Disease/diagnosis , Graft vs Host Disease/physiopathology , Humans , Skin/pathology , Skin Diseases/classification , Skin Diseases/diagnosis , Skin Diseases/physiopathology , Treatment Outcome
12.
J Drugs Dermatol ; 9(7): 851-5, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20677543

ABSTRACT

Angioimmunoblastic T-cell lymphoma (AITL) is a systemic lymphoproliferative disease characterized by a polymorphous neoplastic infiltrate involving lymph nodes as well as extranodal locations, including the skin. Cutaneous involvement is seen in approximately 50 percent of cases and is usually secondary to systemic disease. Patients with cutaneous involvement classically present with a transient morbilliform eruption of the trunk; however, papules, nodules, urticarial plaques and erythroderma have also been reported. In contrast, primary cutaneous AITL is exceedingly rare. The authors report a case of a 79-year-old woman with AITL who presented with primary cutaneous tumors and ulcerated nodules, with no evidence of systemic involvement, hypergammaglobinemia, or B symptoms. Histologically, a subtle lymphoid infiltrate was present, dominated by marked fibrosis and a diffuse infiltrate of neutrophils, eosinophils and plasma cells, mimicking an inflammatory or infectious etiology. This presentation presents a unique diagnostic challenge; careful investigation and strong clinical suspicion must be utilized in order to correctly identify AITL in this setting.


Subject(s)
Dermatitis/pathology , Immunoblastic Lymphadenopathy/pathology , Lymphoma, T-Cell, Cutaneous/pathology , Skin Neoplasms/pathology , Aged , Dermatitis/diagnosis , Diagnosis, Differential , Female , Humans , Immunoblastic Lymphadenopathy/diagnosis , Lymphoma, T-Cell, Cutaneous/diagnosis , Skin Neoplasms/diagnosis
13.
Drug Deliv Transl Res ; 10(1): 70-82, 2020 02.
Article in English | MEDLINE | ID: mdl-31407270

ABSTRACT

Supersaturated drug delivery systems are commonly used to address the problems of poor aqueous solubility posed by most of the active pharmaceutical ingredients (APIs). However, the supersaturated systems are highly unstable due to their high free energy levels and demonstrate a tendency to precipitate. Understanding the crystallization tendency based on the mechanisms of crystallization, that is nucleation and crystal growth, is imperative to design formulation strategies and select appropriate precipitation inhibitors. This study aims to provide a classification system, based on both the nucleation and crystal growth tendency in the solution state of 60 APIs and nutraceuticals (in absence of polymer) from their desupersaturation profiles monitored by UV-Visible spectroscopy. The APIs and nutraceuticals are divided into four classes based on their induction time (tind) and crystal growth rate as fast nucleators-fast crystal growth (class I), fast nucleators-slow crystal growth (class II), slow nucleators-fast crystal growth (class III) and slow nucleators-slow crystal growth (class IV). Most of the molecules fall in the class I and class IV. An easy-to-use protocol for nucleation and crystal growth studies has been optimized. This protocol will find application to assess the crystallization tendency of the molecules in the preliminary screening stages, enabling appropriate formulation strategies to inhibit crystallization.


Subject(s)
Dietary Supplements/classification , Pharmaceutical Preparations/chemistry , Crystallization , Drug Compounding , Pharmaceutical Preparations/classification , Solubility
14.
Drug Deliv Transl Res ; 10(4): 903-918, 2020 08.
Article in English | MEDLINE | ID: mdl-32378174

ABSTRACT

The present study was designed to determine the applicability of a newly derived dimensionless number precipitation parameter, "supersaturation holding capacity (SHC)" in development of amorphous solid dispersion (ASD) of a rapidly crystallizing drug, nisoldipine. Also, ASD preparation from lab scale formulation technique to scalable spray drying technique followed by oral bioavailability study was demonstrated. Solution state screening of polymers was performed by determining nucleation induction time (tin) and SHC. With screened polymers, lab scale ASDs of nisoldipine were prepared using rotary evaporation (solvent evaporation) method, and the optimized stable ASDs were scaled up by spray drying. The ASDs were characterized by DSC, PXRD, and FTIR for amorphous nature and evaluated for apparent solubility, dissolution, and solid-state stability improvement. The spray dried ASDs were additionally evaluated for micrometric properties and oral bioavailability study.PVP grades demonstrated superior crystal growth inhibition properties (with 2-4-fold enhancements in SHC). ASDs prepared by both lab scale and scale-up technique using PVP stabilized the amorphous nisoldipine via antiplasticization effect that maintained the stability under accelerated stability conditions (40 °C/75% RH) for 6 months. Additionally, FTIR study confirmed the role of intermolecular interactions in amorphous state stabilization of PVP-based solid dispersions. PVP-based spray dried ASDs improved the apparent solubility 4-fold for PVP K17 and more than 3-fold for remaining spray dried ASDs. The enhanced solubility was translated to improved dissolution of the drug when compared with crystalline and amorphous form complementing the outcome of the solution state study. The spray dried ASD showed 2.3 and > 3-fold the improvement in Cmax and AUC (0-24 h) respectively when compared with crystalline nisoldipine during oral bioavailability study which highlights the significance of SHC parameter of polymers. The spray dried ASD has shown improved micromeritics properties then crystalline nisoldipine in terms of flow behavior.This unique study provides a rational strategy for selection of appropriate polymer in development of ASDs that can tackle both precipitation during dissolution and amorphous state stabilization in solid state and also considers the SHC in scale-up study. Graphical abstract.


Subject(s)
Chemistry, Pharmaceutical/methods , Animals , Crystallization , Drug Compounding , Drug Liberation , Drug Stability , Feasibility Studies , Female , Nisoldipine/administration & dosage , Nisoldipine/chemistry , Nisoldipine/pharmacokinetics , Polymers/chemistry , Rats, Sprague-Dawley , Solubility , Solvents/chemistry , Suspensions
17.
Talanta ; 199: 679-688, 2019 Jul 01.
Article in English | MEDLINE | ID: mdl-30952315

ABSTRACT

Niclosamide, an anthelmintic drug recently repurposed for its activity against cancer, crystallizes into three solvated forms, two monohydrates (NHa, NHb) and one anhydrous (NAn) form. NAn is sensitive to pseudopolymorphic transformations that affect its dissolution and consequently, its bioavailability. NAn exhibits a polymorphic conversion to metastable monohydrate (NHa) form during high-energy milling in presence of poorly soluble solvents like water. It is hence very important to quantify polymorphic conversion from NAn to NHa, as water is a commonly used solvent during various processing like ball milling and wet granulation. This main objective of the study was to examine the feasibility of Raman, NIR and MIR spectroscopic techniques for identification and quantification of polymorphic forms of niclosamide in binary mixtures and multicomponent mixtures. Calibration models were developed and validated by vibrational spectroscopic techniques in binary mixtures of NAn and NHa and in multicomponent mixtures by chemometric techniques. These techniques were further used to identify and quantify NHa during ball milling, granulation and in presence of other polymorphic forms of niclosamide. Identification and quantification of pseudopolymorphs in binary and multicomponent mixtures with an acceptable recovery of 100.13-102.99% for Raman and 100.07-101.28% for NIR with low % RSD of 2.38-3.12 for both techniques were obtained. The % NHa determined during ball milling and granulation was similar by NIR and Raman. Raman spectroscopy however showed a greater advantage over other techniques in determining the NHa in presence of NHb due to significant difference in the spectral region of hydrates, when compared to NIR and MIR.

18.
Asian J Pharm Sci ; 14(3): 248-264, 2019 May.
Article in English | MEDLINE | ID: mdl-32104456

ABSTRACT

Cellulose derivatives have gained immense popularity as stabilizers for amorphous solid dispersion owing to their diverse physicochemical properties. More than 20 amorphous solid dispersion-based products that have been approved for marketing consist of cellulose derivatives as stabilizers, thus highlighting their importance in generation of amorphous solid dispersions. These polymers offer numerous advantages like drug solubilization, crystallization inhibition and improvement in release patterns of drugs. Exploring their potential and exploiting their chemistry and pH responsive behaviour have led to the synthesis of new derivatives that has broadened the scope of the use of cellulose derivatives in amorphous formulation development. The present review aims to provide an overview of different mechanisms by which these cellulose derivatives inhibit the crystallization of drugs in the solid state and from supersaturated solution. A summary of different categories of cellulose derivatives along with the newly explored polymers has been provided. A special segment on strengths, weaknesses, opportunities, and threats (SWOT) analysis and critical quality attributes (CQAs) which affect the performance of the cellulose based amorphous solid dispersion will aid the researchers in identifying the major challenges in the development of cellulose based solid dispersion and serve as a guide for further formulation development.

19.
Eur J Pharm Sci ; 139: 105048, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31446077

ABSTRACT

Co amorphous systems are supersaturated drug delivery systems which offer a basic platform for delivery of multicomponent adducts (combination of more than one active pharmaceutical ingredient (API)) and/or as a fixed dose combination therapy, in addition to their potential to improve the apparent solubility, dissolution rate and ultimately bioavailability of poorly water soluble APIs. In the present work, a new drug-drug co amorphous system namely valsartan-nifedipine was prepared by quench cooling technique. Prepared co amorphous system was characterized for its solid state behavior with the help of Fourier Transform Infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Powder X Ray Diffractometry (PXRD). The optimized co amorphous system was stable for 1 month when exposed to accelerated stability condition (40 ±â€¯2 °C and 75 ±â€¯5% RH). The improved stability of amorphous nifedipine in co amorphous system was attributed to improved miscibility and intra and intermolecular non-covalent interactions mainly due to presence of hydrogen bonding between valsartan and nifedipine which was studied by FTIR analysis. Co amorphous systems were evaluated by mainly in vitro dissolution and in vivo benefit. In vitro dissolution study showed nearly 5.66 folds and 1.61 folds improvement which was translated to 3.63 and 2.19 times enhancement in vivo Cmax for nifedipine and valsartan respectively.


Subject(s)
Angiotensin II Type 1 Receptor Blockers , Calcium Channel Blockers , Nifedipine , Valsartan , Angiotensin II Type 1 Receptor Blockers/chemistry , Angiotensin II Type 1 Receptor Blockers/pharmacokinetics , Animals , Calcium Channel Blockers/chemistry , Calcium Channel Blockers/pharmacokinetics , Drug Combinations , Drug Compounding , Drug Liberation , Female , Nifedipine/chemistry , Nifedipine/pharmacokinetics , Rats, Sprague-Dawley , Valsartan/chemistry , Valsartan/pharmacokinetics
20.
Case Rep Dermatol Med ; 2019: 7930123, 2019.
Article in English | MEDLINE | ID: mdl-31781414

ABSTRACT

Cutaneous involvement of multiple myeloma (MM) is uncommon, typically occurs in late stage disease, and is a poor prognostic indicator with an approximate eight month median survival. We present a 51-year-old man with relapsed lambda light chain MM who developed abrupt asymptomatic skin metastases. Biopsy revealed a dermis replete of atypical plasma cells, positive for CD138 and CD45. In situ hybridization confirmed lambda light chain restriction. Despite rescue antimyeloma therapy with the anti-CD38 drug daratumumab, he rapidly declined clinically and succumbed to the disease four weeks after presentation. A standard treatment approach for cutaneous MM does not currently exist; however, various techniques to detect cytogenetic abnormalities are emerging and will provide additional prognostic value and direct individualized therapy.

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