Bio-Inspired Vision and Gesture-Based Robot-Robot Interaction for Human-Cooperative Package Delivery.

This research presents a novel bio-inspired framework for two robots interacting together for a cooperative package delivery task with a human-in the-loop. It contributes to eliminating the need for network-based robot-robot interaction in constrained environments. An individual robot is instructed to move in specific shapes with a particular orientation at a certain speed for the other robot to infer using object detection (custom YOLOv4) and depth perception. The shape is identified by calculating the area occupied by the detected polygonal route. A metric for the area's extent is calculated and empirically used to assign regions for specific shapes and gives an overall accuracy of 93.3% in simulations and 90% in a physical setup. Additionally, gestures are analyzed for their accuracy of intended direction, distance, and the target coordinates in the map. The system gives an average positional RMSE of 0.349 in simulation and 0.461 in a physical experiment. A video demonstration of the problem statement along with the simulations and experiments for real world applications has been given here and in Supplementary Material.

Nuclear magnetic resonance-based metabolomics reveals similar metabolomics profiles in undifferentiated peripheral spondyloarthritis and reactive arthritis.

INTRODUCTION: After exclusion of reactive, psoriatic and enteritis-associated arthritis, a group of "undifferentiated" peripheral spondyloarthritis (pSpA) remains. This group shares genetics, T-cell repertoire, and cytokines with reactive arthritis (ReA). ReA is preceded by gut or urogenital infection. Otherwise the two may be similar. We know little of the metabolic pathways driving undifferentiated pSpA or ReA. Nuclear magnetic resonance (NMR)-based metabolomics presents a hypothesis-free approach to study and compare metabolic pathways driving undifferentiated pSpA and ReA. METHODS: Serum and synovial fluid metabolomes of 19 ReA and 13 undifferentiated pSpA, and serum metabolome of 18 controls were profiled using 1 H-based NMR. Partial least square-discriminant analysis (PLS-DA) identified metabolites different in patients as compared to controls. Multivariate analysis confirmed these. Altered metabolic pathways were identified using metabolites set enrichment analysis (MSEA). The serum and synovial fluid metabolomes of ReA and undifferentiated pSpA were compared. RESULTS: Ten serum metabolites of ReA/undifferentiated pSpA were different from those of controls. Six metabolites were different between serum and synovial fluid of these patients. MSEA identified five pathways different between patients and controls, and five pathways different between serum and synovial fluid of patients. PLS-DA showed no difference between the metabolomes of serum or of synovial fluid between ReA and undifferentiated pSpA. DISCUSSION: Identified metabolic pathways may be explored further to understand the pathogenesis and to target therapeutics. The similar immuno-metabolic pathways suggest similar pathogenesis of ReA and undifferentiated pSpA. Thus, they should be studied as a single disease entity.

Arthritis in sarcoidosis: A multicentric study from India.

INTRODUCTION: Ten to 15% of patients with sarcoidosis have associated arthritis. Chronic arthritis is fairly uncommon. There is a paucity of data on articular manifestations of the disease from India. METHODS: Case records of adult patients with sarcoidosis presenting to 11 rheumatology centers from 2005 to 2017 were retrospectively reviewed. Joint involvement was assessed clinically, classified as acute or chronic depending on duration of symptoms less or greater than 6 months, respectively. RESULTS: A total of 117 patients with sarcoid arthritis were reviewed. Forty-five patients were classified as having Lofgren's syndrome. The pattern of joint involvement revealed the ankle to be most commonly affected in both the groups. Shoulder, wrist, metacarpophalangeal, proximal interphalangeal joints of hands and knee joint involvement were significantly more common in chronic sarcoid arthritis. Peripheral lymphadenopathy and uveitis were significantly more frequent in chronic sarcoid arthritis. Forty out of 49 patients with acute arthritis followed up over a median of 1.8 years had achieved complete remission. Twelve out of 16 chronic sarcoid arthritis (median follow up 2.5 years) had achieved complete remission with 15, 12 and five patients on steroids, methotrexate and hydroxychloroquine, respectively. One patient with acute sarcoid arthritis with concomitant interstitial lung disease had died due to lung infection. CONCLUSION: Acute oligoarthritis was the commonest presentation with the ankle being the most commonly affected joint. Upper limb joint (predominantly distal) and knee involvement were more common as reported in our largest series worldwide of chronic sarcoid arthritis in adults. Hilar adenopathy and erythema nodosum were common extra-articular features in both acute and chronic sarcoid arthritis. A limitation of the study was the retrospective nature of the analysis.

Differences between adult and pediatric onset Henoch-Schonlein purpura from North India.

AIM: Henoch-Schönlein purpura (HSP), a primary vasculitis, characterized by purpura, abdominal pain, arthritis and renal involvement, is predominantly a disease of childhood. However, rarely it can occur in adults in whom it is believed to be a more severe form with poor renal outcomes. We aimed to answer if the age of onset affected the clinical spectrum and renal outcomes of the disease in a north Indian population. Hence, we studied the differences in clinical spectrum and renal outcomes between adult-onset HSP and childhood-onset HSP. METHODS: Case records of all adult patients diagnosed with HSP (onset ≥ 18 years) over the last 25 years in our department (1992-2017) were retrieved. Data on clinical features, lab abnormalities and outcomes were extracted and compared with that in pediatric HSP patients (onset < 18 years) seen during the same period. RESULTS: A total of 87 patients, including 30 adults and 57 children, were seen during this period. Compared to children, most of the adults had purpura as the first clinical manifestation (86.7% vs. 56.1%, P < 0.01) whereas abdominal pain was only rarely the initial symptom in adults (10.0% vs. 36.8%, P < 0.02). During the disease course, adults had a higher frequency of joint involvement as compared to children (90.0% vs. 43.9%, P < 0.001). There was no significant difference in the frequency of renal involvement (60.0% vs. 50.9%, P = NS) and gastrointestinal involvement (66.7% vs. 84.2%, P = NS) between adults and children. Outcomes were good in both groups and most adults and children achieved complete recovery (83.3% and 86.0%, respectively). There was no difference in the frequency of immunosuppressive treatment required by the two groups. None of the patients developed renal insufficiency on follow-up. CONCLUSION: Compared to children, adults with HSP seldom have abdominal pain as the first clinical manifestation while joint involvement is seen more commonly in them during the disease course.

IL-17 and IFN-γ producing NK and γδ-T cells are preferentially expanded in synovial fluid of patients with reactive arthritis and undifferentiated spondyloarthritis.

The IL-17/1L-23 axis is important in the pathogenesis of spondyloarthropathy. Innate cells produce IL-17 in addition to Th17 cells. We studied the frequencies of natural killer (NK) (total, CD56bright, CD56dim, perforin+ and granzyme+), NK-T, γδ-T, and IFN-γ+, IL-17+ NK and γδ-T cells in peripheral blood (PB) and synovial fluid (SF) of ReA/uSpA patients. PB from 45 patients and paired SF from 39 patients were studied, together with PB from 18 healthy controls (HC). The frequency of γδ-T cells was decreased (p<0.05) while IL-17 producing NK and γδ-T cells were increased (p<0.05) in PB of patients as compared to HC. In SF, CD56bright NK cells were increased (p<0.001) but had reduced expression of perforin and granzyme (p<0.0001) as compared to PB. Frequency of IL-17+, IFN-γ+ NK and γδ-T cells was higher in SF as compared to PB (p<0.05). We suggest that innate cells by producing pro-inflammatory cytokines may contribute to pathogenesis.

Methotrexate-induced pancytopenia: a case series of 46 patients.

AIM: Methotrexate (MTX) has the potential to cause serious adverse reactions and even mortality. We analyzed the predisposing factors and outcome in patients with MTX-induced pancytopenia admitted into our unit from 1996 to 2015. METHODS: Patients were identified by departmental database search. Pancytopenia was defined as white blood cell count (WBC) < 3500 cells/mm3 , hemoglobin (Hb) < 11 g/dL and platelet count < 150 000 cells/mm3 . Severe pancytopenia was defined as WBC < 2000 cells/mm3 , Hb < 10 g/dL and platelet count < 50 000 cells/mm3 . RESULTS: Forty-six patients were included in the study (female = 35). Twenty-four had been under the care of either primary care physicians or orthopedic surgeons and presented to us with pancytopenia. Sixteen patients had severe pancytopenia. Disease distribution was as follows: rheumatoid arthritis 33, psoriasis eight, systemic sclerosis two and others three. The median dose of MTX was 10 mg/week and median duration of treatment was 11 months. The median cumulative dose was 750 mg. Symptoms at presentation included: oral mucositis (n = 37); fever (n = 24); diarrhea (n = 12), bleeding gums (n = 5) and purpura (n = 3). The potential risk factors were: hypoalbuminemia (n = 23), renal insufficiency (n = 14), dosing errors (n = 13) and non-supplementation of folates (n = 7). Thirteen patients died. WBC at admission was found to determine survival (P < 0.05). CONCLUSION: In patients on MTX, oral mucositis and fever can herald pancytopenia. MTX-induced pancytopenia is associated with high mortality. WBC at admission is the most important prognostic factor. There is need for increased awareness among physicians to minimize prescribing errors. A national guideline on monitoring of patients on MTX is desirable.

Multiple myeloma masquerading as severe seropositive rheumatoid arthritis with subcutaneous nodules and mononeuritis multiplex.

Multiple myeloma can rarely mimic seronegative rheumatoid arthritis (RA). We report a 55-year-old woman who presented with longstanding deforming polyarthritis with extensive subcutaneous nodules, tenosynovitis, anti-cyclic citrullinated peptide positivity and mononeuritis multiplex. Even though the clinical picture was consistent with seropositive RA, the absence of bone erosion or joint space narrowing on hand and knee radiographs led us to question the diagnosis of RA. Further investigation revealed a diagnosis of multiple myeloma with cutaneous amyloid deposits, based on serum immunofixation, bone marrow aspiration and biopsy of a subcutaneous nodule. The only clue to suspect myeloma from the basic investigations and clinical examination was mild hypercalcemia. This case serves to reiterate the need to maintain a heightened suspicion for other diagnoses even when RA appears most likely.

Gangrene in Takayasu's arteritis: a report of two cases and review of literature.

Takayasu's arteritis (TA) is a granulomatous large vessel vasculitis more commonly seen in India. The vascular inflammation in TA results in stenoses of affected vessels. Usually this is a slow process with good collateral circulation; only rarely does critical limb ischemia result. We present two patients of TA who presented with gangrene of extremities, and review eight prior such patients reported in the literature. With appropriate diagnosis and treatment with oral corticosteroids and low-dose aspirin, none of our patients had recurrence at a mean follow-up of 3.8 ± 2.8 years. Although rare, TA can present with gangrene and rheumatologists need to be aware of this unusual but limb-threatening manifestation of TA to institute appropriate therapy in a timely manner.

Behcet's disease without oral ulcers presenting with erythema nodosum and deep venous thrombosis.

We present a young male with recurrent erythema nodosum and recent deep vein thrombosis with scrotal ulcers but no oral ulcers. He was diagnosed as having Behcet's disease (BD) and subsequently responded to immunosuppressants and anticoagulation. This case highlights that up to 2% patients with BD may not have oral ulcers. Timely institution of therapy in our patient resulted in a favorable outcome.

Refractory polymyositis undergoing remission following antitubercular therapy.

Opportunistic infections pose a significant problem in patients receiving immunosuppressive therapy for autoimmune diseases. We present a case of a woman with polymyositis refractory to high-dose steroid and methotrexate, as a consequence of which she developed miliary tuberculosis. Her myositis went into remission after initiation of antitubercular therapy, in spite of bringing down the intensity of immunosuppression. This is the first reported case of myositis undergoing remission after treating intercurrent infection, and illustrates the complex relationship between autoimmune disease and host response to infection.

Pulmonary co-infection with Nocardia and Aspergillus in a patient with adult-onset Still's disease receiving steroids and tacrolimus.

Patients on immunosuppression are at risk of unusual infections. We present a man diagnosed to have adult-onset Still's disease who, on high-dose oral steroid and tacrolimus, developed a cavitating pneumonia due to co-infection with Aspergillus flavus and Nocardia. Timely diagnosis and institution of appropriate therapy resulted in a favourable clinical outcome. Such co-infection in a patient receiving tacrolimus is rare in the published literature. This case serves to emphasise the need to be vigilant for unusual infections in patients who are immunosuppressed, either due to drugs or underlying disease condition.

Lepra reaction with lucio phenomenon mimicking cutaneous vasculitis.

Leprosy is a disease typically found in the tropics. Patients with leprosy can have varying presentation with constitutional symptoms, joint pains, skin nodules, and rarely a vasculitis-like picture with skin ulcers and neuropathy. We present a young lady who presented with the rare manifestation of skin infarcts mimicking cutaneous vasculitis, diagnosed on histopathology to have Lucio phenomenon on a background of lepromatous leprosy. With increasing migration and widespread use of biologic response modifiers, clinicians all over the world need to be aware of various presentations of leprosy as well as needing to keep an open mind while considering the differential diagnoses of vasculitis.