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1.
Prague Med Rep ; 125(1): 69-78, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38470440

RESUMO

Gorlin-Goltz syndrome (GGS) is an infrequent multisystemic disease with an autosomal dominant trait, which depicted presence of numerous basal cell carcinoma in conjunction with multiorgan abnormalities. This syndrome may be diagnosed early by a dentist by routine radiographic exams in the first decade of life, since the keratocystic odontogenic tumour are usually one of the first manifestations of the syndrome. This article includes a case report of the GGS with regard to its history, incidence, etiology, features, investigations, diagnostic criteria, keratocystic odontogenic tumour and treatment modalities.


Assuntos
Síndrome do Nevo Basocelular , Carcinoma Basocelular , Tumores Odontogênicos , Neoplasias Cutâneas , Criança , Humanos , Síndrome do Nevo Basocelular/diagnóstico , Fenótipo
2.
Nat Commun ; 14(1): 8335, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097575

RESUMO

The combination of low-temperature scanning tunnelling microscopy with a mass-selective electro-spray ion-beam deposition established the investigation of large biomolecules at nanometer and sub-nanometer scale. Due to complex architecture and conformational freedom, however, the chemical identification of building blocks of these biopolymers often relies on the presence of markers, extensive simulations, or is not possible at all. Here, we present a molecular probe-sensitisation approach addressing the identification of a specific amino acid within different peptides. A selective intermolecular interaction between the sensitiser attached at the tip-apex and the target amino acid on the surface induces an enhanced tunnelling conductance of one specific spectral feature, which can be mapped in spectroscopic imaging. Density functional theory calculations suggest a mechanism that relies on conformational changes of the sensitiser that are accompanied by local charge redistributions in the tunnelling junction, which, in turn, lower the tunnelling barrier at that specific part of the peptide.


Assuntos
Aminoácidos , Sondas Moleculares , Peptídeos/química , Sequência de Aminoácidos , Microscopia de Tunelamento
3.
J Coll Physicians Surg Pak ; 32(9): 1219-1221, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36089726

RESUMO

Mucormycosis is an acute opportunistic infection caused by a saprophytic fungus found in the soil, decaying fruits, and vegetables. It is a rapidly progressing fungal infection mainly seen in nose and its surrounding sinuses due to inhalation of the spores of fungus from the contaminated areas. If not diagnosed and treated early, it can be life-threatening. A case of a 60-year male farmer is reported with an extensive spread of the fungal infection involving alveolar bone of maxilla, zygomatic process, and the right orbit. The radiographs demonstrated alveolar, palatal, and zygomatic bone destruction. The diagnosis of mucormycosis was made through clinical, radiographic, and histopathologic findings. An early diagnosis and treatment with antifungal drugs like amphotericin B and surgical resection can improve the prognosis. Key Words: Mucormycosis, Maxilla, Zygomatic bone, Antifungal.


Assuntos
Mucormicose , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Humanos , Masculino , Maxila/diagnóstico por imagem , Mucormicose/diagnóstico , Mucormicose/tratamento farmacológico
4.
J Family Med Prim Care ; 11(6): 3352-3355, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36119284

RESUMO

Oral proliferative verrucous leukoplakia (OPVL) is a rare form of oral leukoplakia first reported in 1985. It is a longterm progressive condition, which develops initially as a white plaque of hyperkeratosis that eventually becomes a multifocal disease with confluent, exophytic, and proliferative features. It has no racial preference with female predilection, associated with various factors including human papillomavirus (HPV) association, genetic susceptibility, and long-standing low-grade traumatic factors. The malignancy transformation rate varies from 0.13 to 17.5% with frequent recurrences. Here, we have reported two cases of PVL seen over the tongue and palate. It is confirmed by clinical and histopathological features and treated with Vitamin A and its supplements and a long-term follow-up showed no recurrence, and hence, Vitamin A has proven as a potent treatment option of PVL by its antioxidant and epithelialization property.

5.
J Family Med Prim Care ; 11(4): 1549-1551, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35516665

RESUMO

The terminology choriostoma describes a tumor-like lesion belonging to hamartomatous group of pathology, that is, normal tissue found in abnormal location. Osseous choriostomas in oral cavity are rare and mostly the cases have been reported in tongue but rarely arising from the interdental gingiva. There are various pathological entities arising from gingiva that give a thought of wider differential diagnosis starting from inflammatory to traumatic origin. Hamartomas in oral cavity are very rare which can definitely be attributed to the sparse literature which leads to misdiagnosis as well failure to understand its biology. In this report, we present a case of osseous choriostoma arising from interdental gingiva in a young female patient in the lower arch.

6.
Stat Biopharm Res ; 14(3): 270-282, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37275462

RESUMO

Despite numerous innovative designs having been published for phase I drug-combination dose finding trials, their use in real applications is rather limited. As a working group under the American Statistical Association Biopharmaceutical Section, our goal is to identify the unique challenges associated with drug combination, share industry's experiences with combination trials, and investigate the pros and cons of the existing designs. Toward this goal, we review seven existing designs and distinguish them based on the criterion of whether their primary objectives are to find a single maximum tolerated dose (MTD) or the MTD contour (i.e., multiple MTDs). Numerical studies, based on either industry-specified fixed scenarios or randomly generated scenarios, are performed to assess their relative accuracy, safety, and ease of implementation. We show that the algorithm-based 3+3 design has poor performance and often fails to find the MTD. The performance of model-based combination trial designs is mixed: some demonstrate high accuracy of finding the MTD but poor safety, while others are safe but with compromised identification accuracy. In comparison, the model-assisted designs, such as BOIN and waterfall designs, have competitive and balanced performance in the accuracy of MTD identification and patient safety, and are also simple to implement, thus offering an attractive approach to designing phase I drug-combination trials. By taking into consideration the design's operating characteristics, ease of implementation and regulation, the need for advanced infrastructures, as well as the risk of regulatory acceptance, our paper offers practical guidance on the selection of a suitable dose-finding approach for designing future combination trials.

7.
Prague Med Rep ; 122(3): 222-227, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34606435

RESUMO

Melanoma is a malignant neoplasm of the epidermal melanocytes. Awareness and early recognition of pigmented lesion inside oral cavity helps in initial diagnosis and further investigation and treatment. Oral malignant melanoma is a rare aggressive neoplasm commonly seen among middle age. The diagnosis of melanoma initiates from the pre-existing pigmented lesions. The poor prognosis of oral melanomas requires that pigmented lesions of undetermined origin be routinely biopsied. A case of malignant melanoma of hard palate with its clinical, radiological and histopathological presentation along with brief review is presented. Prognosis of these lesion is poor with survival rate of 5 years.


Assuntos
Melanoma , Neoplasias Bucais , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Prognóstico
8.
Small ; 17(42): e2102037, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34528384

RESUMO

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kinetic energy and current density of the fast electrons. Recent studies have demonstrated that the presence of certain species of atoms can catalyze atomic bond dissociation processes under the electron beam by reducing their threshold energy. Most of the reported catalytic atom species are single atoms, which have strong interaction with single-layer graphene (SLG). Yet, no such behavior has been reported for molecular species. This work shows by experimentally comparing the interaction of alkali and halide species separately and conjointly with SLG, that in the presence of electron irradiation, etching of SLG is drastically enhanced by the simultaneous presence of alkali and iodine atoms. Density functional theory and first principles molecular dynamics calculations reveal that due to charge-transfer phenomena the CC bonds weaken close to the alkali-iodide species, which increases the carbon displacement cross-section. This study ascribes pronounced etching activity observed in SLG to the catalytic behavior of the alkali-iodide species in the presence of electron irradiation.

10.
Organometallics ; 40(15): 2478-2488, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34393318

RESUMO

The understanding and control of stereoselectivity is a central aspect in ring-opening metathesis polymerization (ROMP). Herein, we report detailed quantum chemical studies on the reaction mechanism of E-selective ROMP of norborn-2-ene (NBE) with Mo(N-2,6-Me2-C6H3)(CHCMe3)(IMes)(OTf)2 (1, IMes = 1,3-dimesitylimidazol-2-ylidene) as a first step to stereoselective polymerization. Four different reaction pathways based on an ene syn or ene anti approach of NBE to either the syn- or anti-isomer of the neutral precatalyst have been studied. In contrast to the recently established associative mechanism with a terminal alkene, where a neutral olefin adduct is formed, NBE reacts directly with the catalyst via [2 + 2] cycloaddition to form molybdacyclobutane with a reaction barrier about 30 kJ mol-1 lower in free energy than via the formation of a catalyst-monomer adduct. However, the direct cycloaddition of NBE was only found for one out of four stereoisomers. Our findings strongly suggest that this stereoselective approach is responsible for E-selectivity and point toward a substrate-specific reaction mechanism in olefin metathesis with neutral Mo imido alkylidene N-heterocyclic carbene bistriflate complexes.

11.
J Ayub Med Coll Abbottabad ; 33(2): 354, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34137563
12.
J Coll Physicians Surg Pak ; 30(5): 612-613, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34027884
14.
Med Gas Res ; 11(1): 30-33, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642335

RESUMO

Hyperbaric oxygen therapy refers to inhalation of pure oxygen in a closed chamber. Hyperbaric oxygen has a therapeutic effect in numerous pathological conditions, such as decompression sickness, arterial gas embolism, carbon monoxide poisoning and smoke inhalation, osteomylitis, osteoradionecrosis and wound healing. Hyperbaric oxygen therapy is used for treating underlying hypoxia. This review indicates the action of hyperbaric oxygen on biochemical and various physiological changes in cellular level. Narrative review covers the current indications and contraindications of hyperbaric oxygen therapy. The review also focuses on the therapeutic effects of hyperbaric oxygen pretreatment and precondition in different pathological conditions. The complications and side effects of hyperbaric oxygen therapy are discussed.


Assuntos
Oxigenoterapia Hiperbárica , Humanos
15.
Med Gas Res ; 10(4): 189-192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33380587

RESUMO

Application of ozone in oral care comes as new and alternative treatment modality in dentistry. The impact of biological and digital information leads to use of ozone application by various means for numerous treatment options in oral cavity. Ozone is a form of oxygen, which has an effective role in management of oral diseases. This review mainly emphasizes on utility of ozone in oral health care management. Its therapeutic potential and its clinical application in oral pathologies, periodontology, endodontics, oral surgery, prosthodontics, orthodontics, restorative dentistry, wound healing, tooth mineralization as treatment choice are reviewed.


Assuntos
Odontologia , Ozônio/uso terapêutico , Humanos
16.
Prz Menopauzalny ; 19(2): 101-103, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32802020

RESUMO

Postmenopause is a phase of life which leads physical and emotional instability from multiple health related issues. Oral health in this stage of life is also compromised. Oral health has an impact on general wellbeing of the individual as oral cavity is commonly act as a mirror to general health. Menopause is phase in a woman's life when menstrual cycles cease by reduced secretion of the ovarian hormones, such as estrogen and progesterone. This review article has emphasized on the diverse oral presentations of peri- and postmenopausal phase of women's life. Practicing dental surgeons and general physician should be aware of the possible association of postmenopause and its various oral signs and symptoms in this midlife phase of women. It also focuses on its symptomatic management of various oral health issues. This article explains diverse oral conditions in detailed and their management. Stress causing anxiety and depression among this midlife phase of women can lead to alteration in immunity which can again lead to various oral conditions, like lichen planus, apthous ulcer that can cause burning sensation in oral mucosa and alter the food habit. By dealing with all this diverse condition, practicing oral physician can help to reduce and manage oral manifestation of postmenopausal phase of life.

17.
ACS Nano ; 14(4): 4626-4635, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32283013

RESUMO

Formation and characterization of low-dimensional nanostructures is crucial for controlling the properties of two-dimensional (2D) materials such as graphene. Here, we study the structure of low-dimensional adsorbates of cesium iodide (CsI) on free-standing graphene using aberration-corrected transmission electron microscopy at atomic resolution. CsI is deposited onto graphene as charged clusters by electrospray ion-beam deposition. The interaction with the electron beam forms two-dimensional CsI crystals only on bilayer graphene, while CsI clusters consisting of 4, 6, 7, and 8 ions are exclusively observed on single-layer graphene. Chemical characterization by electron energy-loss spectroscopy imaging and precise structural measurements evidence the possible influence of charge transfer on the structure formation of the CsI clusters and layers, leading to different distances of the Cs and I to the graphene.

18.
J Family Med Prim Care ; 9(10): 5127-5131, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33409175

RESUMO

Maintaining a patient's quality of life is main the aim while treating cancer patients. Patients getting treated for oral cancer encountered with numerous symptoms at the time of radiotherapy and most of these are side effect which can persist even after few months to year after the treatment gets over. Radiotherapy is a vital aspect of both curative and palliative cancer care. Understanding the basics complications of radiotherapy along with its primary management of oral symptoms can assist family physicians in providing complete primary care for their cancer patients. Palliative oral care helps to ease symptoms from the cancer treatment. Oral care negligence is still a major cause of worsening of posttreatment quality of life of an individual. The article mainly empathies on the oral health care need to be taken care by primary care physicians in the cancer patients during and after the radiotherapy. Consequences associated with radiotherapy in oral cavity and its systematic overview of preventing and managing acute and chronic condition. It enlightens the importance of dentist role on improving quality of life of these patients.

19.
J Family Med Prim Care ; 8(3): 793-798, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31041203

RESUMO

Pemphigus is comprised of a group of life-threatening autoimmune diseases that is characterized by circulating IgG antibodies targeting several types of keratinocyte antigens. After introduction of systemic steroids, survival has improved dramatically. However, mortality and morbidity were still very high due to side effects of steroids. Pulse therapy is defined as discontinuous/intermittent intravenous infusion of very high doses of corticosteroids along with certain immunosuppressive agents over a short period. This therapy was introduced to minimize the side effects of conventional corticosteroid therapy. The target is to achieve a faster response and stronger efficacy and to decrease the need for long-term use of systemic corticosteroids. As a result, this therapy has gained its popularity since three decades. The purpose of this article is to review the various available pulse therapy regimens with dosage, indications and contraindications and side effects.

20.
J Am Chem Soc ; 141(20): 8264-8276, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31030510

RESUMO

A series of neutral molybdenum imido alkylidene N-heterocyclic carbene (NHC) bistriflate and monotriflate monoalkoxide complexes as well as cationic molybdenum imido alkylidene triflate complexes have been subjected to NMR spectroscopic, X-ray crystallographic, and reaction kinetic measurements in order to gain a comprehensive understanding about the underlying mechanism in olefin metathesis of this new type of catalysts. On the basis of experimental evidence and on DFT calculations (BP86/def2-TZVP/D3/cosmo) for the entire mechanism, olefinic substrates coordinate trans to the NHC of neutral 16-electron complexes via an associative mechanism, followed by dissociation of an anionic ligand (e.g., triflate) and formation of an intermediary molybdacyclobutane trans to the NHC. Formation of a cationic complex is crucial in order to become olefin metathesis active. Variations in the NHC, the imido, the alkoxide, and the noncoordinating anion revealed their influence on reactivity. The reaction of neutral 16-electron complexes with 2-methoxystyrene is faster for catalysts bearing one triflate and one fluorinated alkoxide than for catalysts bearing two triflate ligands. This is also reflected by the Gibbs free energy values for the transition states, Δ G‡303, which are significantly lower for catalysts bearing only one triflate than for the corresponding bistriflate complexes. Reaction of a solvent-stabilized cationic molybdenum imido alkylidene N-heterocyclic carbene (NHC) monotriflate complex with 2-methoxystyrene proceeded via an associative mechanism too. Reaction rates of both solvent-free and solvent-stabilized cationic Mo imido alkylidene NHC catalysts with 2-methoxystyrene are controlled by the cross-metathesis step but not by adduct formation.

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