SYK Model, Chaos and Conserved Charge

We study the SYK model with complex fermions, in the presence of an all-to-all $q$-body interaction, with a non-vanishing chemical potential. We find that, in the large $q$ limit, this model can be solved exactly and the corresponding Lyapunov exponent can be obtained semi-analytically. The resulting Lyapunov exponent is a sensitive function of the chemical potential $\mu$. Even when the coupling $J$, which corresponds to the disorder averaged values of the all to all fermion interaction, is large, values of $\mu$ which are exponentially small compared to $J$ lead to suppression of the Lyapunov exponent.Comment: 18pages, 4 figures, v2:references and acknowledgment added, typos correcte

Purpura fulminans due to acquired protein C deficiency

Purpura fulminans (PF) may be the presenting symptom in a patient with protein C (PC) deficiency. It is a hematological emergency and presents with extensive areas of hemorrhagic necrosis of the skin. PC deficiency is usually genetically inherited. However, we report a 1 year and 4 months boy, who presented with acquired PC deficiency possibly of postinfectious etiology and developed PF

Central nervous system involvement in a case of segmental nevus depigmentosus

Central nervous system involvement in segmental nevus depigmentosus (SND) is rare. A 7-month-old boy having convulsion and segmental hypopigmented patch in the right inguinal region. Magnetic resonance imaging of brain showed bilateral periventricular white matter hypoplasia with prominent subarachnoid spaces and mild dilation of ventricles with mild left cerebral hemispheric atrophy. Association of SND with seizure and white matter lesion has been rarely reported

Friedreich's Ataxia – A Clinical Diagnosis

Friedreich's ataxia (FA) is an autosomal recessive spinocerebellar degenerative disease characterized by hyperexpansion of GAA triplets in Frataxin gene. The hallmark of this disorder is ataxic gait, areflexia, Babinski's sign and positive Romberg test. We report a 9 year old child who presented with all these features and was diagnosed with FA on the basis of these clinical features. There are few case reports of FA where the diagnosis was made so earl

Bullous Henoch–Schonlein purpura with involvement of face

Henoch–Schonlein purpura (HSP) with facial involvement with bullous rashes are extremely rare. A 12-year-old boy presented with abdominal pain and features of arthritis. He also had multiple purpuric rashes over his lower limbs. Gradually, he developed bullous rashes which were seen on his legs and hands and progressed to involve the face. He was confirmed to be suffering from HSP from clinical presentation and skin biopsy. The child responded well to oral steroids. Bullous lesions may be seen in HSP. However, there is neither prognostic significance of this nor does it alter the management. Other causes of bullous lesions should be ruled out. As facial involvement is associated with renal and gastrointestinal involvement, these children should be monitored for sequelae

Common Presentation with Uncommon Diagnosis: Multifocal Epithelioid Hemangioendothelioma

A young female patient presenting with recurrent hemoptysis, neck swelling, and mediastinal mass mimicking lymphadenopathy was admitted to the Institute of Post Graduate Medical Education and Research and SSKM hospital, Kolkata, India. Clinical features, radiological studies, fibre optic bronchoscopy, and fine needle aspiration cytology from the neck swelling created a diagnostic dilemma until surgical resection and immunohistochemistry reports confirmed the diagnosis of multifocal epithelioid hemangioendothelioma, a rare vascular tumor with intermediate malignancy potential. Because it is a slow-progressing disease and due to the non-availability of standard chemotherapy, the patient, and her legal guardian, opted for palliative care only. She was asymptomatic for four years but again presented with hemoptysis, reappearance of the neck swelling on the same side, and a mediastinal mass compressing the superior vena cava and right pulmonary artery. This report describes the diagnostic problems and therapeutic challenges in the management of this rare tumor over a four-year follow-up period. The clinical course emphasizes the highly unpredictable nature of this tumor

Spectrum of diffuse parenchymal lung diseases with special reference to idiopathic pulmonary fibrosis and connective tissue disease: An eastern India experience

Objective: To evaluate the clinical spectrum of diffuse parenchymal lung diseases (DPLD) encountered in the Indian setting and to compare idiopathic pulmonary fibrosis (IPF) and connective tissue disease associated DPLD (CTD-DPLD), the two commonest aetiologies. Materials and Methods: A prospective study of clinical, imaging and laboratory parameters of patients diagnosed as DPLD and followed up in the Pulmonary Medicine Department of a tertiary-care teaching institution in eastern India was conducted over a period of one year. Results: 92 patients of DPLD were diagnosed in the study period with IPF (n = 35, 38.04%), CTD-DPLD (n = 29, 31.5%), hypersensitivity pneumonitis (n = 10, 10.9%), sarcoidosis (n = 5, 5.4%) and silicosis (n = 5, 5.4%) being the common causes. The CTD-DPLD group had a lower mean age (39.5 ± 1.86 vs 56.9 ± 1.12 years), a longer duration of symptoms (3.5 ± 0.27 vs 2.5 ± 0.26 years), more extra pulmonary manifestations, significantly more base line FVC and 6-minute-walk-distance than the IPF patients. 19 patients of IPF (54%) opted for treatment. All the IPF patients had a significant fall in FVC after six months (mean change -0.203 ± 0.01 litres) compared to the CTD-DPLD group (mean change - 0.05 ± 0.04 litres.) Conclusion: CTD-DPLD patients belong to a younger age group, with longer duration of symptoms, more extrapulmonary features, better physiological parameters and better response to therapy than IPF patients. Larger prospective epidemiological studies and enrolment in clinical trials are necessary for better understanding of the spectrum of diffuse parenchymal lung disorders and their therapeutic options

An Updated Review on Epidemiology, Pathophysiology, Diagnosis and Treatment aspects of COVID-19 Infection

In the current era, COVID-19 has become the most familiar term in the whole world. It is caused by the novel coronavirus SARS-CoV-2 which is a mutated congener of SARS COV and MERS COV. As per epidemiological studies, 83959 cases have been recorded only in China with 4637 deaths. More than 215 countries including Korea, Iran, Italy, Germany, Algeria, South Africa, Senegal, Nigeria etc have recorded over nine million deaths due to this pandemic. Diagnosis of COVID-19 can be carried out by several ways like identifying the increased level of lactate dehydrogenase, creatinine kinase, alanine and aspartate dehydrogenase in blood. IgG and IgM antibody detection is a key parameter in detection of SARS CoV-2. The real-time reverse transcriptase-polymerase chain reaction or RT-qPCR test is so far considered the most reliable diagnostic method. Recently, two current approaches get widely used in diagnosis for SARS CoV-2 namely “FELUDA” and “SHERLOCK” offering a cheap and less time taking procedure for the detection of SARS CoV-2. In FELUDA a protein called FnCas9 and a guide RNA (g RNA) helps in recognizing the viral gene which is contained by the sample whereas SHERLOK is associated with Cas12 protein