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1.
Cureus ; 16(2): e54089, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38487147

RESUMO

Acromioclavicular ganglion cysts are uncommon, with only a limited number of cases reported in the medical literature. This case report presents a unique instance of an acromioclavicular ganglion cyst in an 81-year-old male patient, outlining the clinical presentation, diagnostic approach, and successful surgical management. The purpose of this report is to contribute to the existing body of knowledge on this rare condition and highlight the importance of accurate diagnosis and appropriate intervention.

2.
Cureus ; 16(2): e54173, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38496094

RESUMO

Glomus tumors are rare neoplasms originating from the glomus body that predominantly manifest in the subungual region of the digits and are distinguished by severe pain and a heightened sensitivity to cold. Bony erosion associated with glomus tumors is a rare phenomenon. Here, we present a unique case of a glomus tumor situated on the ventromedial aspect of the little finger, leading to notable bony erosion. A 42-year-old female from India presented with a chief complaint of severe and localized pain in the ventromedial region of her right little finger, exacerbated by exposure to cold temperatures. Radiological investigations demonstrated focal bone erosion at the site of the tumor. Surgical excision of the lesion was performed. A fish-mouth incision was made on the ventromedial aspect of the little finger, which was extended to the tip of the finger. The nail bed was kept intact. The tumor was excised using small forceps. The patient experienced complete resolution of symptoms postoperatively and reported no recurrence during the follow-up period. This case report highlights the exceptional presentation of a glomus tumor causing bony erosion on the ventromedial aspect of the little finger, a manifestation rarely encountered in clinical practice. Furthermore, this case contributes to the limited body of literature on this combination of uncommon clinical entities, shedding light on its diagnosis and management.

3.
Cureus ; 15(11): e48771, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38098919

RESUMO

A 41-year-old female patient sought medical attention due to a malunited distal radius fracture with a positive ulnar variance, experiencing wrist pain and limited range of motion. The patient was successfully treated with an isolated ulnar osteotomy and bone grafting, resulting in significant alleviation of symptoms and improved wrist mobility. Various surgical methods have been proposed to address malunited radius fractures, and ulnar osteotomy has shown promise as an effective technique for such cases.

4.
Cureus ; 15(10): e47393, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38021561

RESUMO

Osteoid osteomas (OOs) are non-malignant primary bone abnormalities marked by a central nidus surrounded by reactive sclerosis. They typically manifest as aggravated nocturnal pain that responds to non-steroidal anti-inflammatory drugs (NSAIDs). These growths are most frequently found within the intracortical bone and the diaphysis of elongated bones. Within the realm of uncommon conditions, intra-articular OOs (IAOOs) exhibit distinctive presentations, often leading to postponed or inaccurate diagnoses. We present a patient with OO at the distal femur, accessible through the knee joint, which was intraoperatively identified and localized using a needle pricking technique and treated by arthrotomy and mosaicplasty.

5.
J Photochem Photobiol B ; 245: 112733, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37311303

RESUMO

In cells that are exposed to terrestrial sunlight, the indole moiety in the side chain of tryptophan (Trp) can suffer photo/oxidative damage (POD) by reactive oxygen species (ROS) and/or ultraviolet light (UV-B). Trp is oxidized to produce N-formylkynurenine (NFK), a UV-A-responsive photosensitizer that further degenerates into photosensitizers capable of generating ROS through exposure to visible light. Thus, Trp-containing proteins function as both victims, and perpetrators, of POD if they are not rapidly replaced through protein turnover. The literature indicates that protein turnover and DNA repair occur poorly in chromosomal interiors. We contend, therefore, that basic chromosomal proteins (BCPs) that are enveloped by DNA should have evolved to lack Trp residues in their amino acid sequences, since these could otherwise function as 'Trojan horse-type' DNA-damaging agents. Our global analyses of protein sequences demonstrates that BCPs consistently lack Trp residues, although DNA-binding proteins in general do not display such a lack. We employ HU-B (a wild-type, Trp-lacking bacterial BCP) and HU-B F47W (a mutant, Trp-containing form of the same bacterial BCP) to demonstrate that the possession of Trp is deleterious to BCPs and associated chromosomal DNA. Basically, we show that UV-B and UV-A (a) cause no POD in HU-B, but cause extensive POD in HU-B F47W (in vitro), as well as (b) only nominal DNA damage in bacteria expressing HU-B, but extensive DNA damage in bacteria expressing F47W HU-B (in vivo). Our results suggest that Trp-lacking BCPs could have evolved to reduce scope for protein-facilitated, sunlight-mediated damage of DNA by UV-A and visible light, within chromosomal interiors that are poorly serviced by protein turnover and DNA repair machinery.


Assuntos
Proteínas de Bactérias , Cromossomos , Dano ao DNA , Genoma , Histonas , Estresse Oxidativo , Luz Solar , Triptofano , Humanos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/efeitos da radiação , Cromossomos/química , Cromossomos/metabolismo , Cromossomos/efeitos da radiação , Cromossomos Bacterianos/química , Cromossomos Bacterianos/metabolismo , Cromossomos Bacterianos/efeitos da radiação , Escherichia coli/genética , Escherichia coli/efeitos da radiação , Genoma/genética , Genoma/efeitos da radiação , Histonas/química , Histonas/metabolismo , Histonas/efeitos da radiação , Concentração de Íons de Hidrogênio , Marcação In Situ das Extremidades Cortadas , Fatores Hospedeiros de Integração/química , Oxirredução/efeitos da radiação , Fenilalanina/genética , Fármacos Fotossensibilizantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/química , Triptofano/deficiência , Triptofano/genética , Triptofano/metabolismo , Raios Ultravioleta
6.
J Biol Chem ; 299(5): 104637, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36963493

RESUMO

The bacterial chromosome, known as its nucleoid, is an amorphous assemblage of globular nucleoprotein domains. It exists in a state of phase separation from the cell's cytoplasm, as an irregularly-shaped, membrane-less, intracellular compartment. This state (the nature of which remains largely unknown) is maintained through bacterial generations ad infinitum. Here, we show that HU and Dps, two of the most abundant nucleoid-associated proteins (NAPs) of Escherichia coli, undergo spontaneous complex coacervation with different forms of DNA/RNA, both individually and in each other's presence, to cause accretion and compaction of DNA/RNA into liquid-liquid phase separated condensates in vitro. Upon mixing with nucleic acids, HU-A and HU-B form (a) biphasic heterotypic mixed condensates in which HU-B helps to lower the Csat of HU-A and also (b) multiphasic heterotypic condensates, with Dps, in which demixed domains display different contents of HU and Dps. We believe that these modes of complex coacervation that are seen in vitro can serve as models for the in vivo relationships among NAPs in nucleoids, involving local and global variations in the relative abundances of the different NAPs, especially in demixed subdomains that are characterized by differing grades of phase separation. Our results clearly demonstrate some quantitative, and some qualitative, differences in the coacervating abilities of different NAPs with DNA, potentially explaining (i) why E. coli has two isoforms of HU, and (ii) why changes in the abundances of HU and Dps facilitate the lag, logarithmic, and stationary phases of E. coli growth.


Assuntos
Proteínas da Membrana Bacteriana Externa , DNA Bacteriano , Proteínas de Ligação a DNA , Proteínas de Escherichia coli , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas da Membrana Bacteriana Externa/ultraestrutura , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Isoformas de Proteínas/metabolismo , RNA Bacteriano
7.
Front Genome Ed ; 4: 870108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35558825

RESUMO

CRISPR/Cas-mediated editing has revolutionized crop engineering. Due to the broad scope and potential of this technology, many studies have been carried out in the past decade towards optimizing genome editing constructs. Clearly, the choice of the promoter used to drive gRNA and Cas9 expression is critical to achieving high editing efficiency, precision, and heritability. While some important considerations for choosing a promoter include the number and nature of targets, host organism, mode of transformation and goal of the experiment, spatiotemporal regulation of Cas9 expression using tissue-specific or inducible promoters enables higher heritability and efficiency of targeted mutagenesis with reduced off-target effects. In this review, we discuss specific studies that highlight the prospects and trade-offs associated with the choice of promoters on genome editing and emphasize the need for inductive exploration and discovery to further advance this area of research in crop plants.

8.
Biochem Biophys Res Commun ; 560: 27-31, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-33964504

RESUMO

In enteric bacteria such as Escherichia coli, there are two homologs of the DNA-binding nucleoid associated protein (NAP) known as HU. The two homologs are known as HU-A and HU-B, and exist either in the form of homodimers (HU-AA, or HU-BB) or as heterodimers (HU-AB), with different propensities to form higher-order oligomers. The three different dimeric forms dominate different stages of bacterial growth, with the HU-AB heterodimer dominating cultures in the stationary phase. Due to similarities in their properties, and the facile equilibrium that exists between the dimeric forms, the dimers are difficult to purify away from each other. Although HU-AA and HU-BB can be purified through extensive ion-exchange chromatography, reestablishment of equilibrium interferes with the purification of the HU-AB heterodimer (which constitutes ∼90% of any population with equal numbers of HU-B and HU-A chains). Here, we report the creation of a functional analog of HU-AB that does not appear to partition to generate any minority populations of HU-AA or HU-BB. The analog was constructed through genetic fusion of the HU-B and HU-A chains into a single polypeptide (HU-B-A) with a glycine/serine-rich linker of 11 amino acids separating HU-B from HU-A, and a histidine tag at the N-terminus of HU-B. HU-B-A folds to bind 4-way junction DNA, and displays a significant tendency to form dimers (i.e., analogs of HU tetramers), and a higher thermodynamic stability than HU-BB or HU-AA, thus explaining why it dominates mixtures of HU-B and HU-A chains.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Escherichia coli/química , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dimerização , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Conformação Proteica em alfa-Hélice , Dobramento de Proteína , Multimerização Proteica , Desdobramento de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Termodinâmica , Ureia
9.
J Biol Chem ; 296: 100532, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33713701

RESUMO

In biofilms, bacteria that possess a negatively charged surface are embedded within a matrix of polymers consisting mainly of negatively charged extracellular DNA (e-DNA). In all likelihood, a multivalent positively charged substance, for example, a basic protein, exists within biofilms to neutralize charge-charge repulsions and act as a 'glue' attaching negatively charged bacteria to negatively charged e-DNA; however, no protein capable of doing so has yet been identified. We decided to investigate whether a highly abundant nucleoid-associated histone-like protein (HU) happens to be the glue in question. In recent years, HU has been shown to possess qualities that could be considered desirable in the proposed glue, for example, (a) availability in association with e-DNA; (b) multivalent DNA binding; (c) non-sequence-specific DNA-binding; (d) enhancement of biofilm formation upon exogenous addition, and (e) disruption of biofilms, upon removal by HU-cognate antibodies. Geometric considerations suggest that basic residues in HU's canonical and noncanonical DNA-binding sites can interact with sugar-linked terminal phosphates in lipopolysaccharide (LPS) molecules in bacterial outer membranes. Here, using genetic, spectroscopic, biophysical-chemical, microscopy-based, and cytometry-based experiments, we demonstrate that HU's DNA-binding sites also bind to LPS, that this facilitates DNA-DNA, DNA-LPS, and LPS-LPS interactions, and that this facilitates bacterial clumping and attachment of bacteria to DNA. Exogenous addition of HU to bacteria in (nonshaken) cultures is shown to cause cells to become engulfed in a matrix of DNA, potentially arising from the lysis of bacteria with vulnerable cell walls (as they strain to grow, divide, and move away from each other, in opposition to the accreting influence of HUs).


Assuntos
Biofilmes/crescimento & desenvolvimento , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Vesículas Extracelulares/metabolismo , Proteínas de Ligação a DNA/genética , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/genética
10.
Biochem Biophys Res Commun ; 534: 47-52, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310187

RESUMO

HU, a DNA-binding protein, has a helical N-terminal region (NTR) of ∼44 residues and a beta strand- and IDR-rich C-terminal region (CTR) of ∼46 residues. CTR binds to DNA through (i) a clasp (two arginine/lysine-rich, IDR-rich beta hairpins that bind to phosphate groups in the minor groove), (ii) a flat surface (comprising four antiparallel beta strands that abut the major groove), and (iii) a charge cluster (two lysine residues upon a short C-terminal helix). HU forms a dimer displaying extensive inter-subunit CTR-CTR contacts. A single-chain simulacrum of these contacts (HU-Simul) incorporating all DNA-binding elements was created by fusing together the CTRs of Escherichia coli HU-A and Thermus thermophilus HU. HU-Simul is monomeric, binds to dsDNA and cruciform DNA, but not to ssDNA.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Dicroísmo Circular , DNA/química , DNA Cruciforme/química , DNA Cruciforme/metabolismo , DNA de Cadeia Simples/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Engenharia de Proteínas/métodos , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Thermus thermophilus/genética
11.
Ci Ji Yi Xue Za Zhi ; 32(2): 219-221, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32269959

RESUMO

Acute pseudo-obstruction of the colon is known as Ogilvie syndrome (OS). There are varied causes of OS. Myxedema ileus (MI) as a cause of acute pseudo-obstruction is rare. Surgery in cases of MI is reserved only in cases of cecal distension of >12 cm, bowel ischemia, and perforated bowel. We present a rare case of a 71-year-old female who was operated for abdominal compartment syndrome secondary to MI.

12.
BMJ Case Rep ; 12(11)2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31678921

RESUMO

Diffuse plane xanthomatosis is a normolipemic non-Langerhan cell histiocytosis. Clinically, patient presents as asymptomatic yellowish plaques involving eyelids, neck, upper trunk and flexures. Usually, there is an associated haematological or lymphoproliferative malignancy which may precede or follow dermatological manifestations by many years. Rarely inflammatory dermatosis like atopic eczema, photosensitive dermatosis, erythroderma, previous scars and lymphoedema have been found to be associated with these xanthomas. We are reporting a 46-year-old male patient who had a history of photosensitivity for the last 15 years and subsequently developed diffuse plane normolipemic xanthomas.


Assuntos
Dermatite Fototóxica/diagnóstico , Xantomatose/etiologia , Histiócitos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Xantomatose/patologia
13.
BMJ Case Rep ; 12(11)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31753825

RESUMO

Mucinous cystadenoma are rare benign mucin-producing tumours. Primary mucinous neoplasms most commonly involve ovary, pancreas or appendix. They may rupture to produce mucous ascites/pseudomyxoma peritonei. We are describing a 51-year-old man who presented to us with symptomatic gallstone disease but during preoperative ultrasound was found to have cystic lesions in spleen with free fluid in the abdomen. Splenectomy and drainage of mucin were done. Histopathology was done and a final diagnosis of primary mucinous cystadenoma of spleen with mucinous ascites was made.


Assuntos
Cistadenoma Mucinoso/complicações , Pseudomixoma Peritoneal/etiologia , Neoplasias Esplênicas/complicações , Cistadenoma Mucinoso/diagnóstico por imagem , Cistadenoma Mucinoso/cirurgia , Diagnóstico Diferencial , Drenagem , Humanos , Masculino , Pessoa de Meia-Idade , Pseudomixoma Peritoneal/diagnóstico por imagem , Ruptura Espontânea , Esplenectomia , Neoplasias Esplênicas/diagnóstico por imagem , Neoplasias Esplênicas/cirurgia , Tomografia Computadorizada por Raios X , Ultrassonografia
14.
BMJ Case Rep ; 12(7)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31302622

RESUMO

Transurethral resection of prostate (TURP) is the most common operation performed for obstruction secondary to prostatic enlargement. Though considered as a safe procedure, occasionally life-threatening complications may be seen. Intravesical explosion, secondary to ignition by diathermy of the accumulated mixture of hydrogen, hydrocarbons and higher concentration of oxygen, is a rarely reported complication (only 38 cases reported until). We are reporting a 60-year-old man suffering from benign prostatic hyperplasia in whom during TURP bladder explosion occurred which was suspected early and immediately explored and repaired leading to a favourable outcome.


Assuntos
Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/efeitos adversos , Bexiga Urinária/lesões , Humanos , Complicações Intraoperatórias/etiologia , Masculino , Pessoa de Meia-Idade , Ruptura
15.
BMJ Case Rep ; 12(3)2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30852501

RESUMO

Parkes Weber syndrome (PWS) is a rare disorder characterised by arteriovenous (AV) fistula, along with capillary, lymphatic, venous malformations and limb hypertrophy. Stewart-Bluefarb syndrome is a variant of acroangiodermatitis, which is associated with congenital AV malformation/fistulas. It usually begins early in life, unilaterally over lower extremities presenting as violaceous to dusky coloured macules, papules or plaques with tendency to ulcerate. We are reporting a case of AV malformation fulfilling the triad of PWS and presenting with acroangiodermatitis.


Assuntos
Acrodermatite/etiologia , Angiomatose/etiologia , Fístula Arteriovenosa/etiologia , Malformações Arteriovenosas/etiologia , Síndrome de Sturge-Weber/complicações , Acrodermatite/patologia , Adolescente , Angiomatose/patologia , Fístula Arteriovenosa/patologia , Malformações Arteriovenosas/patologia , Humanos , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/patologia , Masculino
16.
Clin Med Insights Case Rep ; 12: 1179547619828723, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30792586

RESUMO

Aggressive digital papillary adenocarcinoma (ADPA) is a rare tumour of eccrine origin. They present as asymptomatic nodules with flattened and thickened surface skin, most commonly on fingers and toes. It mimics many benign entities and tumours, hence leading to a delay in diagnosis. It has a high metastasizing potential, but is slowly progressive. Histopathologically, it has both a nodular and a cystic component with papillary projections into cystic spaces. We present a 54-year man with a tumorous mass on right heel, which was diagnosed by histopathology and immunohistochemistry as ADPA. Our case had ADPA lesion, a rarely reported malignancy on an uncommon site with distant metastasis.

17.
BMJ Case Rep ; 12(1)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679229

RESUMO

Idiopathic calcinosis (IC) is deposition of calcium hydroxyapatite crystals or amorphous calcium with no predisposing cause. IC presents in juxta-articular tissue in a tumour-like fashion is known as idiopathic tumoral calcinosis (ITC). Recurrent trauma and chronic pressure are thought to be the triggering factors. It usually presents in adolescents and adults. Presentation in early childhood is a rarity. We are reporting ITC in an 8-year-old child with the onset at 4 years of age.


Assuntos
Calcinose/diagnóstico , Dermatopatias/diagnóstico , Calcinose/complicações , Criança , Cotovelo/diagnóstico por imagem , Feminino , Pé/diagnóstico por imagem , Humanos , Radiografia , Dermatopatias/complicações , Úlcera Cutânea/etiologia
18.
BMJ Case Rep ; 11(1)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30567103

RESUMO

Situs inversus totalis is a rare genetic disorder. Single-incision laparoscopic cholecystectomy (SILC) in situs inversus totalis has been reported rarely. SILC has an advantage of being easier than conventional laparoscopic cholecystectomy in addition to better cosmesis and reduced postoperative pain. We report a case of single-incision laparoscopic cholecystectomy done in a young woman with situs inversus totalis using conventional laparoscopic instruments.


Assuntos
Colecistectomia Laparoscópica/instrumentação , Cálculos Biliares/cirurgia , Laparoscopia/métodos , Situs Inversus/diagnóstico por imagem , Feminino , Cálculos Biliares/diagnóstico por imagem , Humanos , Dor Pós-Operatória/prevenção & controle , Radiografia/métodos , Doenças Raras/cirurgia , Instrumentos Cirúrgicos/normas , Resultado do Tratamento , Ultrassonografia/métodos , Adulto Jovem
19.
BMJ Case Rep ; 11(1)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30567110

RESUMO

Dyskeratosis congenita (DKC) also known as Zinsser-Cole-Engman syndrome is a progressive genetic disease with a classical presentation characterised by a triad of reticulate pigmentation of skin, nail dystrophy and leukoplakia. It may be a multisystem disease with the involvement of haematological, gastrointestinal, genitourinary, neurological, ophthalmic, pulmonary and skeletal system. We report a sporadic case of DKC presenting with poikiloderma, nail dystrophy and oral leukoplakia.


Assuntos
Disceratose Congênita/patologia , Leucoplasia Oral/patologia , Doenças da Unha/patologia , Unhas Malformadas/patologia , Adulto , Assistência ao Convalescente , Diagnóstico Diferencial , Disceratose Congênita/diagnóstico , Disceratose Congênita/genética , Trato Gastrointestinal/patologia , Humanos , Masculino , Transtornos da Pigmentação/patologia , Pele/patologia
20.
BMJ Case Rep ; 20182018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-29982187

RESUMO

Hypomelanosis of Ito is a rare neurocutaneous syndrome. Cutaneous involvement is characterised by streaks and swirls of hypopigmentation arranged in a Blaschkoid pattern. Neural involvement along with other systemic features are seen. We report a case of a 13-year-old boy who presented with the characteristic skin involvement of hypomelanosis of Ito, mental retardation, teeth abnormalities and gynaecomastia along with psoriasis.


Assuntos
Ginecomastia/complicações , Hipopigmentação/complicações , Anormalidades Dentárias/etiologia , Adolescente , Diagnóstico Diferencial , Humanos , Hipopigmentação/diagnóstico , Deficiência Intelectual/etiologia , Masculino , Psoríase/etiologia
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