Biomedical subjects

R A Prayson

Publications and source records attributed to R A Prayson.

At least 19 recordsLinked to original sources

PubMed2007

The value of interictal diffusion-weighted imaging in lateralizing temporal lobe epilepsy.

BACKGROUND: A subgroup of patients with nonlesional temporal lobe epilepsy (TLE) has no evidence of hippocampal sclerosis on standard temporal lobe protocol MRI. OBJECTIVE: To investigate whether interictal diffusion-weighted imaging adds lateralizing information in patients with TLE with and without lateralizing conventional MRI. METHODS: We studied 22 patients (9 right, 13 left TLE) who had undergone temporal lobectomy and 18 control subjects. We measured hippocampal volumes on high- resolution coronal magnetization-prepared rapid gradient echo scans. Apparent diffusion coefficients (ADCs) for the entire hippocampus and three arbitrarily defined areas of interest within the hippocampal head, body, and tail were measured from the coregistered ADC map. Pathology was reviewed and correlated with imaging findings. RESULTS: Fourteen of 22 patients had hippocampal atrophy on MRI (defined as volume asymmetry greater than 2 SDs compared with asymmetry in the control group). Overall, resected hippocampi (n = 22) were significantly smaller than contralateral hippocampi as well as ipsilateral hippocampi in controls. ADCs were significantly higher in resected hippocampi than contralateral hippocampi as well as ipsilateral hippocampi in controls. These differences were also observed within the three areas of interest. ADCs in the hippocampi contralateral to the epileptogenic zone (n = 22) were also higher than in ipsilateral hippocampi in controls. In the subgroup of eight patients with nonlateralizing conventional MRIs, ADCs of resected hippocampi were not significantly different compared with the contralateral side. Pathology in these patients revealed gliosis only without apparent neuron loss. CONCLUSION: Interictal apparent diffusion coefficients confirm lateralization in patients with hippocampal atrophy on standard temporal lobe protocol MRI. However, they do not provide lateralizing information in patients with nonlateralizing conventional MRI.

Adolescent↗

PubMed2006

Predictors of outcome after temporal lobectomy for the treatment of intractable epilepsy.

To assess short- and long-term seizure freedom, the authors reviewed 371 patients who underwent anterior temporal lobectomy to treat pharmacoresistant epilepsy. The mean follow-up duration was 5.5 years (range 1 to 14.1 years). Fifty-three percent of patients were seizure free at 10 years. The authors identified multiple predictors of recurrence. Results of EEG performed 6 months postoperatively correlated with occurrence and severity of seizure recurrence, in addition to breakthrough seizures with discontinuation of antiepileptic drugs.

Anterior Temporal Lobectomy↗

PubMed2004

Branch retinal artery occlusions as the presenting feature of primary central nervous system vasculitis.

A 39-year-old woman presented with multiple branch retinal artery occlusions almost three years before developing a mass lesion containing calcium in the left frontal lobe. Brain biopsy revealed a small vessel vasculitis and ischemic necrosis of brain with dystrophic calcification. We believe this to be the first case of primary CNS vasculitis with branch retinal artery occlusions and brain calcification.

Adult↗

PubMed2003

West Nile virus infection: a new acute paralytic illness.

OBJECTIVE: To determine the clinical, laboratory, electrodiagnostic, radiologic, and pathologic characteristics that define the spectrum of CNS disease caused by West Nile virus (WNV) infection. METHODS: The records of all patients hospitalized at the Cleveland Clinic from August 2002 to September 2002 with WNV infection were reviewed. RESULTS: Of 23 cases, the median age was 74 years old, and 74% were men. Symptoms included fever (100%), altered mental status (74%), gastrointestinal complaints (43%), back pain (35%), and rash (26%). In half, meningitis or encephalitis overlapped with flaccid weakness that progressed over 3 to 8 days, with a tendency to be proximal and asymmetric. Laboratory abnormalities included hyponatremia (30%) and initial CSF neutrophilic pleocytosis. Electrodiagnostic studies in two patients showed reduced motor amplitudes with normal conduction velocities and active denervation. In two other patients, reduced sensory amplitudes were also seen. MRI changes included cauda equina enhancement and parenchymal spinal cord signal abnormalities and parenchymal or leptomeningeal signal changes in the brain. Autopsy in three cases showed chronic perivascular inflammation in the brain and inflammatory changes with anterior horn cell loss in the spinal cord. CONCLUSION: An overlapping spectrum of meningitis, encephalitis, and myeloradiculitis occurs in CNS WNV infection. Fever, rash, abdominal and back pain, preceding a proximal, asymmetric flaccid weakness, with CSF pleocytosis help distinguish the motor syndrome from Guillain-Barré syndrome. Pathologic changes in the CNS resembled poliomyelitis.

Acute Disease↗

PubMed2001

In situ expression of interleukin-4 (IL-4) receptors in human brain tumors and cytotoxicity of a recombinant IL-4 cytotoxin in primary glioblastoma cell cultures.

We have reported that human malignant glioma cell lines express high levels of plasma membrane interleukin-4 receptors (IL-4R). We have also reported that biopsy/surgical samples or primary explant cell cultures from brain tumors express mRNA and protein for the IL-4Ralpha chain, a primary IL-4-binding protein. However, whether IL-4R are expressed in brain tumors in situ has not been resolved. In addition, expression of IL-4R on the cell surface of various normal brain tissues is not known. We examined the expression of IL-4R by using a monoclonal antibody to the IL-4Ralpha chain (also known as IL-4R beta) in surgical/biopsy samples of brain tumor tissues by immunohistochemistry. Our data indicate that 15 of 18 glioblastoma multiforme (GBMs) tumors obtained from two different institutions and 12 other brain tumor samples are moderately to intensely positive for IL-4Ralpha. In contrast, although IL-4Ralpha mRNA was expressed, no IL-4R protein was detectable in two adult and one pediatric brain tissue specimens. In addition, a commercially available human neural tissue grid containing fixed tissues from various areas of brain showed no positive staining for the IL-4Ralpha chain. IL-4Ralpha expression was also demonstrated on astrocytoma grades I, II, and III. Because IL-4 cytotoxin comprised of a circularly permutated IL-4 and a mutated form of Pseudomonas exotoxin [IL4(38-37)-PE38KDEL] is cytotoxic to IL-4R-expressing cells, we tested whether primary GBM explant cell cultures are sensitive to IL-4 cytotoxin. Our data indicate that 13 of 15 GBM cell cultures were 25-74 times more sensitive to IL-4 cytotoxin compared with normal human astrocytes or the NT2 neuronal cell line. These observations indicate that human brain tumors in situ overexpress IL-4R compared with normal brain tissues, thus confirming our previous conclusions that IL-4R in brain tumors may serve as an attractive target for anticancer therapy.

Brain Neoplasms↗

PubMed2001

Epidermal growth factor regulates astrocyte expression of the interleukin-4 receptor via a MAPK-independent pathway.

Human astrocytes express the interleukin (IL)-4 receptor alpha chain (IL-4R alpha) in vitro and in vivo but mechanisms governing astrocyte IL-4R alpha expression have not been established. We hypothesized that epidermal growth factor (EGF) and IL-4, agents that profoundly affect astrocyte proliferation, might also alter IL-4R alpha expression. Exposure to EGF for 24 h enhanced IL-4R alpha mRNA levels; in contrast, IL-4 yielded no increase. Immunoblotting demonstrated that EGF but not IL-4 increased astrocyte IL-4R alpha protein after 2--4 days of exposure. Similarly, EGF but not IL-4 strongly activated phosphorylation of p42/p44 extracellular regulated kinase isoforms, a reaction blocked by the mitogen-activated protein kinase (MAPK) inhibitor, PD98059. PD98059 also blocked EGF-stimulated DNA synthesis but not IL-4R alpha mRNA levels, while antibody to the EGF receptor (erbB1) blocked both EGF effects. Data suggest that astrocyte IL-4R alpha expression is upregulated by EGF but not by IL-4 in an EGF-receptor-dependent manner and that mechanisms are independent of MAPK activation.

Astrocytes↗

PubMed2001

Desmoplastic infantile ganglioglioma (DIG): cranial ultrasound findings.

Desmoplastic infantile ganglioglioma (DIG) is a rare brain tumor encountered in infants. In spite of its large size at presentation and occasional high mitotic activity on histopathology, the tumor has a good prognosis. A 7-month-old baby girl developed increasing head circumference. On ultrasound, a large multicystic mass was seen. We report the cranial ultrasound findings for the first time. Correlative imaging of this recently recognized entity is shown.

Brain Neoplasms↗

PubMed2001

Choroid plexus papilloma with osseous and adipose metaplasia.

Rare cases of osseous and chondroid metaplasia in choroid plexus papillomas have been described. We report a case of left lateral ventricular choroid plexus papilloma presenting in a 25-year-old man. The tumor demonstrates prominent calcification with associated osseous metaplasia and a region of adipose metaplasia, which has not been previously described in these tumors. There is no evidence of mucin in the papilloma on mucicarmine and alcian blue stains. A MIB-1 labeling index (marker of cell proliferation) of 0.1% was noted. P53 immunoreactivity was not observed in the papilloma. Ann Diagn Pathol 5:43-47, 2001.

Adipose Tissue↗

PubMed2001

Neuropathology associated with ventricular assist devices: an autopsy series of 33 patients.

The ventricular assist device (VAD) is a mechanical pump that has been shown to be an effective modality of cardiac support in patients with heart failure refractory to pharmacologic intervention and who are awaiting cardiac allograft transplantation. Neuropathologic findings in these patients have not been well described. We retrospectively reviewed 2,632 autopsy reports (between 1990 and 2000) and found 64 patients who received VADs. Of these 64 patients, brain and spinal cord tissue was available for review in 33 patients (25 males and eight females; age range, 4 to 69 years; mean age, 52 years). The study group was composed of these 33 patients. Ventricular assist devices were in place from one to 603 days (mean 49 days). Twenty-five patients had left VAD, three had right VAD, and five had biventricular VADs. Brain weights ranged from 928 g to 1,740 g (mean 1,325 g). The most common central nervous system pathologic findings included infarct (N = 23; 70%), acute neuronal necrosis (N = 22; 67% focal and N = 1; diffuse anoxic encephalopathy), hemorrhage (N = 14; 42%), and herniations (N = 7; 21%). Two patients had no neuropathologic findings at autopsy. Cause of death was central nervous system-related in eight patients (24%) including six with massive parenchymal hemorrhage and herniations, one with brainstem infarction, and one with air embolism (radiographically diagnosed). The most common causes of death in the remaining 25 patients included sepsis (n = 10; 30%), pneumonia (n = 4; 12%), and embolic events with widespread infarcts (n = 4; 12%). The most common neuropathologic findings in patients with VAD were related to ischemia and infarction. In a significant subset of patients, central nervous system pathology, particularly hemorrhage with herniation, was the primary cause of death. Ann Diagn Pathol 5:67-73, 2001.

Adolescent↗

PubMed2001

Clinicopathologic study of retinoblastoma including MIB-1, p53, and CD99 immunohistochemistry.

UNLABELLED: Retinoblastoma is the most common intraocular tumor of childhood and has served as a model for the understanding or tumorigenesis. This study retrospectively examines the clinicopathologic features of 19 retinoblastomas and defines the MIB-1 (cell proliferation marker), p53 (tumor suppression gene), and CD99 (HBA71 or MIC2 antibody) immunoreactivity in 10 selected cases. Nineteen patients (11 boys), ranging in age from 6 to 47 months (mean, 20 months), were included for study. Clinical presentations included: leukocoria (n = 12), strabismus (n = 6), apparent decreased visual acuity (n = 5), and proptosis (n = 1). Five patients had bilateral tumors and one neoplasm arose in a patient with a known family history of retinoblastoma. All tumors were histologically characterized by a proliferation of small cells with high nuclear-to-cytoplasmic ratios. Commonly encountered histologic features included necrosis (n = 17, 89%), calcification (n = 16, 84%), fleurettes (n = 14, 74%), and Flexner-Wintersteiner rosettes (n = 11, 58%). Retinal involvement was noted in 18 tumors (95%) and optic nerve invasion in six cases (32%). The surgical optic nerve margin was positive in one case. Mitosis counts were evaluable in 18 cases and ranged from 1 to 42 mitotic figures/10 high power field (mean, 13 mitotic figures/10 high power field). Ten tumors were evaluated with MIB-1, p53, and CD99 antibodies by paraffin immunohistochemistry. MIB-1 labeling indices ranged from 31.4 to 77.1 (mean, 49.4). p53 immunostaining was observed in six tumors; less than 10% of tumor cells were noted to be p53 positive in each case. CD99 positivity was demonstrable focally in three tumors. Adjuvant chemotherapy and/or radiation therapy was administered in six patients. Tumor recurrence was not observed in any of the patients with a mean follow-up of 8.9 years. Only one patient died (20 years after enucleation) because of metastatic osteosarcoma. IN CONCLUSION: (1) Fleurettes and Flexner-Wintersteiner rosettes are variable findings in retinoblastoma. (2) Retinoblastomas are characterized by marked cell proliferation as evidenced by generally high mitosis counts and extremely high MIB-1 labeling indices, but this does not appear to adversely impact on prognosis. (3) Unlike peripheral primitive neuroectodermal tumors, most retinoblastomas do not stain positively with antibody to CD99. (4) Limited p53 immunostaining was present in 60% of tumors studied. (5) Enucleation with negative optic nerve margin is potentially curative in patients with retinoblastoma.

12E7 Antigen↗

PubMed2001

Mycobacterium avium intracellulare otitis media.

Atypical mycobacterial infections of the middle ear are extremely rare. To our knowledge, only eight cases have been reported in the literature, five of which involve Mycobacterium avium intracellulare. We present a case of culture-proven, M. avium intracellulare otomastoiditis in an 8-year-old boy with common variable immunodeficiency syndrome. The patient clinically presented with pain and otorrhea. The histopathology was marked by acid-fast bacilli-laden histiocytes. Consideration of this entity in the differential diagnosis of chronic, recalcitrant otorrhea can lead to timely diagnosis, treatment, an decreased morbidity.

Child↗

PubMed2001

Metastatic adenocarcinoma to a pituitary adenoma.

Metastatic tumor to a pituitary adenoma has rarely been documented in the literature. We report a case of a 60-year-old man who presented with a history of progressive blurred vision and an incomplete homonymous hemianopsia. Magnetic resonance imaging showed a 5 cm heterogeneous mass which focally was contrast enhancing, involving the sella turcica and extending into the right cavernous sinus region. After worsening symptoms, repeat magnetic resonance imaging showed an increase in size of the lesion. Histologically, the mass consisted of a metastatic adenocarcinoma to a nonsecreting pituitary adenoma. The carcinoma stained focally positive with antibodies to carcinoembryonic antigen, cytokeratin 20, and p53 (60% of tumor cells), and did not stain with antibody to cytokeratin 7. The histologic appearance and immunohistochemical profile of the metastasis suggests a colorectal primary.

Adenocarcinoma↗

PubMed2001

Ultrastructural examination of the axillary skin biopsy in the diagnosis of metabolic diseases.

There is little information in the literature regarding the usefulness of ultrastructural examination of axillary skin biopsies in the evaluation of metabolic diseases. This is a retrospective clinicopathologic review of 143 patients who underwent axillary skin biopsies as part of evaluations for metabolic disease. Twenty-three (16%) had abnormalities, classified as follows: mitochondrial (n = 12), lysosomal (n = 6), increased glycogen (n = 3), nonspecific cytoplasmic inclusions (n = 2), ceroid lipofuscinosis (n = 1), and intradermal giant cells containing vacuoles and tubular inclusions (n = 1). Muscle biopsies were performed in 13 of the 23 patients; 11 showed abnormalities, including those related to mitochondria (n = 4) and other nonspecific changes (n = 7). Two patients underwent postmortem examination. Follow-up was available in 21 patients. A clinical or biochemical diagnosis was reached in 11 patients: metachromatic leukodystrophy (n = 2), electron transport chain abnormalities (n = 2), glutaric aciduria type II (n = 1), Unverricht disease (n = 1), Lennox-Gastaut syndrome (n = 1), ketotic hypoglycemia of childhood (n = 1), probable Leigh disease (n = 1), 5-methyl tetrahydrofolate homocystine methyltransferase deficiency (n = 1), and pyruvate dehydrogenase deficiency (n = 1). Of the 120 patients with negative skin biopsy results, 29 had abnormal findings on muscle (n = 27), nerve (n = 7), or brain (n = 3) biopsies. One patient had an abnormal heart biopsy result, and 3 patients underwent postmortem examinations. Follow-up was obtained in 27 of 29 patients. Diagnoses were achieved in 15 patients: electron transport chain abnormalities (n = 5), cortical dysplasia (n = 3), myoclonic epilepsy (n = 1), leukodystrophy (n = 2), Pallister-Killian mosaic syndrome (n = 1), Rett syndrome (n = 1), Landau-Kleffner syndrome (n = 1), and mitochondrial cardiomyopathy (n = 1). In conclusion, axillary skin biopsy is helpful in the evaluation of some causes of metabolic disease, but often the findings are nonspecific. A negative biopsy result does not rule out the possibility of metabolic disease, but a positive result may provide direction for further evaluation.

Adolescent↗

PubMed2001

The significance of perivascular inflammation in the absence of arteritis in temporal artery biopsy specimens.

We retrospectively compared 81 temporal artery biopsy specimens demonstrating perivascular inflammation without evidence of temporal arteritis and 76 specimens demonstrating no inflammation. Patients with perivascular inflammation included 43 women (mean age, 71.2 years). Nineteen patients met the 1990 American College of Rheumatology (ACR) criteria for the diagnosis of temporal arteritis. All patients demonstrated chronic perivascular inflammation consisting primarily of lymphocytes. Granulomas were noted in 4 specimens. Internal elastic lamina disruption, intimal fibroplasia, and dystrophic calcification were noted in 86 arteries examined. Fibrosis or scarring of the vessel walls was observed in 10 specimens. Corticosteroid therapy was beneficial to 33 of 56 patients. In patients with no evidence of inflammation (50 women; mean age, 66.6 years), 21 met ACR criteria for temporal arteritis. Histologically, disruption of the elastic lamina was noted in 75 of 81 arteries biopsied, intimal fibroplasia in 66, microcalcifications in 5, and fibrosis or scarring in 5. In this group, 47 patients received corticosteroid therapy; clinical improvement was noted in 28. Patients with chronic perivascular inflammation but no arteritis seem no more likely to have temporal arteritis on clinical grounds than similar patients without inflammation on biopsy.

Adrenal Cortex Hormones↗

PubMed2001

Diagnostic yield muscle biopsy in patients with clinical evidence of mitochondrial cytopathy.

We retrospectively reviewed 118 muscle biopsy specimens from 113 patients with clinical and/or biochemical evidence of mitochondrial cytopathy. Light microscopic evaluation revealed histologic abnormalities in 65 specimens. The most common histologic findings included angular atrophic esterase-positive muscle fibers, type II muscle atrophy, regenerating muscle fibers, and scattered cytochrome-oxidase deficient fibers. Ragged red fibers were noted in 3 specimens on a Gomori trichrome stain. Electron microscopic evaluation was performed in 113 muscle specimens, and in 34, no abnormalities were identified. Increased numbers of mitochondria, particularly in the subsarcolemmal region, were identified in 54 specimens. Increased mitochondrial size was seen in 8 specimens and paracrystalline mitochondrial inclusions in 3. Other ultrastructural findings included focally increased glycogen deposition, focal Z-band streaming, and focally increased lipid accumulation. For 39 cases, concomitant skin biopsy specimens were available; abnormalities were identified by electron microscopy in 12. The majority of biopsy specimens demonstrated some light or electron microscopic abnormality. Specific histologic findings suggestive of mitochondrial abnormalities (partial cytochrome oxidase deficiency, ragged red fibers) were noted in a minority of cases. Ultrastructural evidence of mitochondrial abnormalities was noted in the majority of cases.

Adolescent↗

PubMed2001

Dura mater involvement in ochronosis (alkaptonuria).

Clinical manifestations of alkaptonuria have been well described and are most commonly characterized by ochronosis or pigmentation of connective tissue. Sites most commonly involved in ochronosis include joints, heart, skin, and kidney. We describe a 66-year-old woman with a history of alkaptonuria who had widespread ochronosis. The dura mater showed extensive pigment deposition, which was evident both grossly and microscopically at autopsy. To our knowledge, description of dura mater involvement by ochronosis has not been previously reported in the literature.

Aged↗

PubMed2001

Bcl-2, Bcl-x, and Bax expression by immunohistochemistry in inclusion body myositis: a study of 27 cases.

CONTEXT: Bcl-2, Bcl-x, and Bax are among the variety of proteins that have been described as being involved in the regulation of apoptotic cell death. Bcl-2 and Bcl-x(L) inhibit apoptosis, and Bax is proapoptotic. OBJECTIVE: To evaluate the expression of Bcl-2, Bcl-x, and Bax in inclusion body myositis (IBM).Design.-We examined muscle specimens from 27 patients (17 men, 10 women) with IBM to evaluate Bcl-2, Bcl-x, and Bax expression by immunohistochemistry. RESULTS: Patient ages ranged from 29 to 80 years (mean 62.2 years). All biopsies were marked by endomysial chronic inflammation, muscle fiber necrosis, and regeneration. Rimmed (autophagic) vacuoles were present in all cases. Ragged red fibers were noted in 4 biopsies (15%), and cytochrome oxidase-deficient fibers were found in 10 biopsies (37%). Ultrastructural evidence of intranuclear or cytoplasmic tubulofilamentous inclusions, confirming the diagnosis of IBM, were noted in all cases. Paracrystalline mitochondrial inclusions were seen in 5 biopsies (18.5%). Inflammatory cells stained positively with Bcl-2 in all biopsies, Bax in 26 biopsies (96%), and Bcl-x in 8 biopsies (30%). Degenerating muscle fibers were highlighted with Bax in 24 biopsies (89%), Bcl-2 in 2 biopsies (7%), and Bcl-x in 3 biopsies (11%). Regenerative muscle fibers were noted to stain with Bax in 24 muscles (89%), Bcl-2 in 21 muscles (78%), and Bcl-x in 4 muscles (15%). Rimmed vacuoles were highlighted by Bax in 24 biopsies (89%) and only rarely by Bcl-2 (n = 2, 7%) and Bcl-x (n = 3, 11%). A subsarcolemmal staining pattern was observed in 21 biopsies (78%) with Bax, 6 biopsies (22%) with Bcl-2, and only 1 biopsy (4%) with Bcl-x. CONCLUSIONS: (1) Bax (proapoptotic) immunostaining highlighted most autophagic vacuoles; (2) subsarcolemmal Bax and Bcl-2 immunoreactivity may be associated with mitochondrial defects that are commonly noted in IBM; (3) Bcl-2 and Bax immunoreactivity were not confined to degenerating muscle fibers and in fact appeared to be expressed more commonly in regenerating fibers, suggesting that their expression may be independent of apoptosis in the setting of IBM.

Adult↗

PubMed2000

Seizure outcome after surgery for epilepsy due to malformation of cortical development.

PURPOSE: To explore seizure outcome after surgery for focal epilepsy due to malformation of cortical development (MCD), with focus on the role of MRI. METHODS: Thirty-five patients who had surgery for intractable focal epilepsy due to MCD identified by preoperative MRI and confirmed by histopathologic analysis of resected tissue were studied. Patients were aged 3 months to 47 years (median, 14 years) at the time of surgery. Duration of follow-up was 1 to 7.9 (mean, 3.4) years. RESULTS: At latest follow-up, 17 patients (49%) had Engel Class I outcome with no seizures or auras only; eight patients (23%) had Class II outcome, with rare disabling seizures; seven patients (20%) had worthwhile improvement; and three patients (9%) had no improvement. Seizure-free outcome tended to be more frequent among patients who had complete resection of unilateral MCD (excluding hemimegalencephaly) based on postoperative MRI (7/12; 58%), compared with patients with unilateral MCD who had incomplete resection (3/11; 27%), but the difference was not significant. The frequency of seizure-free outcome did not differ significantly between children (8/14; 57%), adolescents (7/15; 47%) or adults (2/6; 33%); between patients who had daily (12/24; 50%), weekly (4/9; 44%), or monthly (1/2; 50%) seizures preoperatively; between patients who had temporal (2/6; 33%) or extratemporal or multilobar resections (14/28; 50%); or between patients who were (9/16; 56%) or were not (8/19; 42%) studied with subdural electrodes. Results for all analyses were similar when analyzed at latest available follow-up or at 1 year after surgery. CONCLUSIONS: Surgery can offer seizure-free outcome for approximately one half of carefully selected patients with intractable focal epilepsy due to MCD. Complete resection of the MRI-apparent lesion may improve the likelihood for favorable outcome. MRI evidence of hemimegalencephaly or bilateral MCD suggests a low likelihood for postoperative freedom from seizures.

Adolescent↗