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At least 1,315 records · Page 73Linked to original sources

PubMed2005

The psychophysics of glaucoma: improving the structure/function relationship.

Perimetry of some kind remains an important tool in the detection, diagnosis and monitoring of glaucomatous damage to the visual pathway. However, recent studies have served to reinforce the suspicion that conventional perimetry does not possess the sensitivity to detect the earliest signs of functional loss resulting from glaucoma. The relationship between differential light threshold and ganglion cell loss is extremely weak and, in the early stages of glaucoma, non-existent. Alternative, more novel perimetric techniques seem to offer promise of better detectability for early loss by claiming to tap in to one or other of the separate parallel pathways of the visual system. While some of these tests show potential for better detection and monitoring of glaucoma, the reasons why this might be so are not always clearly formulated or represented. This leads to misunderstanding of what the test actually measures and of the glaucomatous disease process itself. This paper seeks to revisit and review the theory underlying psychophysical testing of visual function related to glaucoma and stresses the importance of developing tests that are based on a firm theoretical understanding of visual function and processing in order to both detect glaucoma at an earlier stage and better understand the mechanisms of loss from the disease process.

Glaucoma↗

PubMed1991

Altered cell function in microgravity.

Physiological changes in humans during spaceflight upon return to earth have been attributed to systemic adaptation, response to stress, and lack of normal exercise. Studies from the Skylab, SL-3, and D-1 missions have demonstrated that significant physiological alterations are seen in single cell prokaryotes and eukaryotes, as well as in animal tissues. Basic cellular functions such as electrolyte concentration, cell growth rate, glucose utilization, bone formation, response to growth stimulation, and exocytosis are modified in microgravity. Many of the physiological changes seen in humans, vertebrate and simple organisms in spaceflight may originate from dysfunction of basic biological mechanisms caused by microgravity. Aging humans share many of the symptoms seen in astronauts during spaceflight. These include reduced cardiac function, loss of bone and reduced immune response and orthostatic hypotension. It is possible that some of physiological adaptations seen in aging may share common physiological basis with those changes seen in spaceflight. Since microgravity affects prokaryotic and eukaryotic cell function at a subcellular and molecular level, space offers us an opportunity to learn more about basic biological mechanisms which are essential to life.

Adaptation, Physiological↗

PubMed1985

The extensor digitorum brevis muscle island flap for soft-tissue loss around the ankle.

The extensor digitorum brevis muscle flap, which has already been suggested as a local flap for the foot, has been applied by us in 2 cases with excellent results. This flap, as with other muscle flaps, provides an excellent bed for the skin graft. Furthermore, because of its width, it allows for covering an area of skin loss 5 X 7 cm in size in areas that are difficult to cover by other reconstructive means. The arch of rotation of this flap allows for coverage of the lateromedial and posterior surfaces of the ankle with no functional loss at the donor site. The relative ease of elevating this flap presents a reasonable justification for its wider application as a single local procedure for skin problems around the ankle.

Adult↗

PubMed2000

[Abdominal aortic aneurysm treated by endovascular stent-graft and conventional surgical repair: a comparison].

OBJECTIVE: To evaluate the feasibility of abdominal aortic aneurysm (AAA) treated by endovascular stent-graft. METHODS: The clinical data of 52 patients with AAA treated by endovascular stent-graft (n = 20) and conventional surgical repair (n = 32) were analysed retrospectively. Patients conditions, operative hours, blood loss, function recovery and complications were compared. RESULTS: No significant difference was observed in sex, age, other disease, anesthesia risk category, aneurysm type, aneurysm diameter, technical success rate, and mortality rate between the groups (P > 0.05). The patients who underwent intraluminal treatment had significant reductions in operative time, blood loss, intensive care unit and hospitalization. But there was a high complication rate in the endovascular stent-graft group. All complications were connected with the interventional technique; endo-leak was the chief complication after operation. CONCLUSIONS: Endovascular treatment has marked merits such as reduced trauma, short hospitalization stays, and early functional recovery. It is suitable for the patients who can't undergo open surgical repair. But the complications caused by this technique needs further study.

Aged↗

PubMed2001

Marination performance of pale broiler breast meat.

Pale, soft, exudative (PSE) meat is a growing problem in the poultry industry and is characterized by rapid postmortem pH decline. The low pH condition while the body temperature has not yet chilled leads to protein denaturation, causing pale color and reduced water-holding properties. The water loss and the protein damage from the PSE condition may impact the ability of the muscle to uptake or retain marinade solution. This study was conducted to determine if a marination with salt and alkaline phosphates could rectify the protein functionality losses imparted by the PSE condition and to determine if marinade pH affects pale and normal fillets in the same manner. Pale (n = 175) and normal-colored (n = 160) fillets were collected from deboning lines at two commercial processing plants based on subjective color evaluation alone. The fillets were then characterized by L* value, pH, and expressible moisture. They were then tumbled with a solution containing salt and sodium tripolyphosphate at 4 C for 30 min. Marinade uptake, drip loss, and cook loss were all measured. As expected, the pale fillets had higher L* values and lower pH values than the normal fillets. For the pH 9 marinade, uptake and drip losses were similar in pale and normal fillets, but cook loss from pale fillets was greater than that of the normal fillets. Marinade solution at pH 11 showed no difference in pH or cook loss between pale and normal fillets. These results indicate that the PSE condition cannot be reversed by the marination treatments used in this study.

Animals↗

PubMed2000

Alterations of the PPP1R3 gene in hematological malignancies.

PPP1R3 (protein phosphatase 1, regulatory subunit 3) is a candidate tumor suppressor gene at chromosome 7q31, since nonsense and missense mutations of the PPP1R3 gene have been detected in a variety of human cancers. Loss of chromosome 7q is a recurrent abnormality in hematological malignancies, especially of myeloid lineage, and a common region of 7q deletions has been mapped to 7q31. Thus, it has been suggested that 7q31 harbors a tumor suppressor gene whose functional loss contributes to leukemogenesis. To evaluate the possible involvement of the PPP1R3 gene in the development of hematological malignancies, we examined 72 leukemia and lymphoma cell lines for alterations of the PPP1R3 gene by PCR-SSCP and direct sequence analyses. Mutations were detected in 1 (2.8%) of 36 myeloid cell lines, 4 (20.0%) of 20 B-lineage lymphoid cell lines and none of 16 T-lineage lymphoid cell lines. All the mutations were heterozygous, and they consisted of two missense mutations and three silent mutations. The PPP1R3 gene was expressed in cell lines of various cell lineages. These results indicate that PPP1R3 is not a major target of 7q deletions in myeloid leukemia, however, alterations of the PPP1R3 gene may contribute to the development of a subset of hematological malignancies.

Amino Acid Substitution↗

PubMed1998

[One hundred years of orthopedics in the Netherlands. VI. Surgical treatment of rheumatoid arthritis].

The prevalence of rheumatoid arthritis is about 1%. Loss of independence during daily activities is closely related to the multiple joint involvement of these patients. Also, chronic systemic autoimmune diseases and the extra-articular lesions cause considerable comorbidity. Goal of medical treatment is to reduce disease activity and local joint destruction. The surgical treatment consists of joint protective surgery and joint reconstructive surgery. The former procedure inhibits rapid progression of joint destruction by eradicating the bulk of synovial tissue. The latter procedure compensates for functional loss of an extremity by arthroplasties (both endoprostheses and arthrodeses) to increase the patient's independence. The perfect long-lasting functional prosthesis is available for some joints (hip and knee), but still in development for other joints (e.g. finger joints). In case of surgical reconstruction, a plan for possible complications (e.g. loosening) and their functional implications for the specific patient, should be part of the surgical indication policy. The outcome after a surgical procedure is closely related to preoperative patient factors (e.g. joint destruction) and the surgical expertise. Co-ordination of the treatment plan has to be done by the rheumatologist in close conjunction with the orthopedic/rheuma surgeon.

Arthritis, Rheumatoid↗

PubMed2005

Measures of visual function and time to driving cessation in older adults.

PURPOSE: Older adults may place restrictions on their driving once their visual function has become compromised, presumably in an effort to ensure their safety. It is important to identify the types of visual function loss that lead to driving cessation to better understand the relationship between vision and driving. METHODS: Data were used from the Salisbury Eye Evaluation project, a cohort study of 2520 older adults followed for 8 years with four rounds of data collection. Multiple measures of visual function were objectively assessed and driving information was collected through self-report from subjects or proxies. Cox regression was used to examine whether those with worse baseline and 2-year change scores in acuity, contrast sensitivity, visual fields, and glare sensitivity were more likely to stop driving after baseline after adjusting for demographic and health variables. RESULTS: Those with worse baseline scores in acuity, contrast sensitivity, central or lower peripheral visual fields were more likely to stop driving (trend p values < 0.05). Also, those who experienced 2-year losses in acuity, contrast sensitivity, or lower peripheral visual fields were more likely to stop driving (trend p values < 0.05). With the vision variables entered into the same model, baseline acuity and 2-year acuity loss were no longer statistically significant. Those with worse baseline scores in contrast sensitivity, central and lower peripheral visual fields were more likely to stop driving (trend p values < 0.05), and those who had 2-year losses in contrast sensitivity and lower peripheral visual fields were more likely to stop driving (trend p values < 0.05). Interactions with gender, other drivers in the house, or cognitive impairment were not detected. CONCLUSIONS: We present prospective data that indicate that older adults with worse scores in multiple measures of vision are more likely to stop driving and that contrast sensitivity and visual fields are most associated with driving cessation.

Accidents, Traffic↗

PubMed1995

Neurologic evaluation of the rat during sciatic nerve block with lidocaine.

BACKGROUND: Quantitative behavioral testing is necessary to establish a reproducible measure of differential functional blockade during regional anesthesia. Methods for assessment of the neurologic status (mental status, posture, gait, proprioception, motor function, autonomic function, and nociception) in veterinary neurology were adapted for the rat and used to monitor functional changes separately during a sciatic nerve block. METHODS: Sprague-Dawley rats were acclimated to laboratory routine before the study so that lidocaine (0.1 ml, 1%) could be injected near the sciatic notch without any chemical restraint. The onset, duration, and magnitude of functional losses were monitored. Proprioceptive integrity was evaluated by assessing the response to tactile placing and the hopping response. Extensor postural thrust, a test for postural reactions in small animals, was assessed on a digital balance and found adequate for quantifying motor function. Analgesia was assessed by measuring withdrawal response latencies to noxious thermal stimulation (51 degrees C) and to superficial and deep noxious pinches. Autonomic function was monitored by measuring skin temperature. Contralateral limb function was used as an internal control, and injection of saline was used as an external control in separate, control animals. RESULTS: Onset of postural and gait abnormalities were observed as early as 40 s after injection. On each occasion proprioceptive impairment was detected first, followed by impairment of motor function and nociception. Complete absence of proprioception occurred from 10 to 30 min (n = 9) and of motor function at 30 min after injection (n = 10); both functions were fully recovered by 120 min. A unilateral increase in skin temperature on the foot was detected by 1 min; had reached its maximum change, 5.3 +/- 0.7 degrees C, at 10 min; and had returned to control levels at 60 min after injection (n = 12). Withdrawal response to cutaneous or superficial pain was absent in all ten animals from 5 to 30 min whereas the response to deep pain was absent in all ten animals at 20 min only. The response to noxious stimulation recovered at 90 min. Attention was paid to the temporal relation of the impairment of various functions. CONCLUSIONS: Quantitative observations of the onset, offset, and intensity of differential functional impairment or block over time will make it possible to establish the doses and conditions for local anesthetics that result in differential nerve block and will permit comparison of these changes among different drugs and "clinical" protocols.

Animals↗

PubMed2002

Neutrophil specific granule deficiency and mutations in the gene encoding transcription factor C/EBP(epsilon).

Neutrophil specific granule deficiency (SGD) is a rare congenital disorder. The neutrophils of these patients display atypical bilobed nuclei; lack expression of at least one primary and all secondary and tertiary granule proteins; and possess defects in chemotaxis, disaggregation, receptor upregulation, and bactericidal activity. SGD patients suffer frequent and severe bacterial infections. Although the first of five patients worldwide was reported in the early 1970s, the molecular basis for the defect was discovered only recently. This review presents data implicating the functional loss of the myeloid transcription factor CCAAT/enhancer binding protein (C/EBP(epsilon)) as a causative agent in the development of SGD. The murine model for SGD provides evidence for defects in eosinophil granule gene expression and indicates abnormalities in macrophage maturation and function. Deficiencies in multiple myeloid lineages, in addition to neutrophils, indicate the importance of C/EBP(epsilon) in regulating important innate immune and inflammatory responses critical for host defense.

Animals↗

PubMed1990

Is thioridazine retinopathy progressive? Relationship of pigmentary changes to visual function.

Thioridazine toxicity has been described as a 'progressive chorioretinopathy', but this designation can be misleading. During the first year after thioridazine exposure retinal pigmentation evolves from a granular to a patchy or nummular appearance. However, visual function and the electroretinogram typically improve during this period. Some cases may show chorioretinal atrophy and functional loss many years later, but there is little evidence for ongoing drug-related progression. Late atrophy may represent degeneration of cells that were injured subclinically at the time of initial drug exposure. Although thioridazine toxicity produces an evolving pigmentary disturbance, functional changes must be monitored independently of fundus appearance.

Atrophy↗

PubMed1987

[Expert assessment of reduced earning capacity in legal accident insurance following traumatic loss of the spleen].

For legally binding assessment of reduced earning capacity after loss of spleen in adolescents and adults--in accordance with the Federal German compulsory accident insurance regulations--the article offers a brief review of expertising practice and then proceeds to examine dogmatically which of the cases of subsequent damage after loss of spleen are relevant according to German social security laws. The risk covered by Federal German compulsory accident insurance is critically discussed while bearing in mind that assessment of reduced earning capacity is done exclusively under the viewpoint of objectifiable functional losses.

Adult↗

PubMed1994

Genetic analysis of Fasciclin II in Drosophila: defasciculation, refasciculation, and altered fasciculation.

The Drosophila neural cell adhesion molecule Fasciclin II (Fas II) is expressed dynamically on a subset of embryonic CNS axons, many of which selectively fasciculate in the vMP2, MP1, and FN3 pathways. Here we show complementary fasII loss-of-function and gain-of-function phenotypes. Loss-of-function fasII mutations lead to the complete or partial defasciculation of all three pathways. Gain-of-function conditions, using a specific control element to direct increased levels of Fas II on the axons in these three pathways, rescue the loss-of-function phenotype. Moreover, the gain-of-function can alter fasciculation by abnormally fusing pathways together, in one case apparently by preventing normal defasciculation. These results define an in vivo function for Fas II as a neuronal recognition molecule that controls one mechanism of growth cone guidance-selective axon fasciculation--and genetically separates this function from other aspects of outgrowth and directional guidance.

Animals↗

PubMed2006

Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study.

Normal aging is associated with progressive functional losses in perception, cognition, and memory. Although the root causes of age-related cognitive decline are incompletely understood, psychophysical and neuropsychological evidence suggests that a significant contribution stems from poorer signal-to-noise conditions and down-regulated neuromodulatory system function in older brains. Because the brain retains a lifelong capacity for plasticity and adaptive reorganization, dimensions of negative reorganization should be at least partially reversible through the use of an appropriately designed training program. We report here results from such a training program targeting age-related cognitive decline. Data from a randomized, controlled trial using standardized measures of neuropsychological function as outcomes are presented. Significant improvements in assessments directly related to the training tasks and significant generalization of improvements to nonrelated standardized neuropsychological measures of memory (effect size of 0.25) were documented in the group using the training program. Memory enhancement appeared to be sustained after a 3-month no-contact follow-up period. Matched active control and no-contact control groups showed no significant change in memory function after training or at the 3-month follow-up. This study demonstrates that intensive, plasticity-engaging training can result in an enhancement of cognitive function in normal mature adults.

Adult↗

PubMedDate not supplied

Short-wavelength automated perimetry can predict glaucomatous standard visual field loss by ten years.

Examination of visual fields using standard achromatic automated perimetry (SAP) is essential for glaucoma management. However, as many as 35-50% of retinal ganglion cells can be lost before a visual field defect is detected. Previous studies have indicated that examination of the short-wavelength (blue) sensitive color system may be able to detect early functional loss in glaucoma. Moreover, it has been reported to detect glaucomatous visual field loss as many as 5 years earlier than SAP. We describe the case of a patient who demonstrated visual field defects on short-wavelength automated perimetry (SWAP) ten years prior to developing visual field defects in SAP.

Female↗

PubMed1989

The reverse digital artery flap for fingertip reconstruction.

Reverse digital artery flaps were performed successfully to resurface the major fingertip defect in 10 patients and the volar defect of the middle phalanx in 1. This thin flap with its long vascular pedicle containing a digital artery and its perivascular cuff tissue has a wide arc of transposition. It can be used to reconstruct the defect located from the proximal phalanx to the fingertip of all fingers. No loss of the flap in this series was noted. The procedure is a time-saving, one-stage operation. Patients who received this procedure had no uncomfortable immobilization of the hand or long hospitalization. It also causes no disfigurement and no functional loss of the involved digit. Our clinical experience showed favorable results.

Adult↗

PubMed2002

Peri-ischemic aminoguanidine fails to ameliorate neurologic and histopathologic outcome after transient spinal cord ischemia.

Inhibition of neurotoxic events that lead to delayed cellular damage may prevent motor function loss after transient spinal cord ischemia. An important effect of the neuroprotective substance aminoguanidine (AG) is the inhibition of inducible nitric oxide synthase (iNOS), a perpetrator of focal ischemic damage. The authors studied the protective effects of AG on hind limb motor function and histopathologic outcome in an experimental model for spinal cord ischemia, and related these findings to the protein content of iNOS in the spinal cord. Temporary spinal cord ischemia was induced by 28 minutes of infrarenal balloon occlusion of the aorta in 40 anesthetized New Zealand White rabbits. Animals were assigned randomly to two treatments: saline (n = 20) or AG (n = 20; 100 mg/kg intravenously before occlusion). Postoperatively, treatment was continued with subcutaneous injections twice daily (saline or 100 mg/kg AG). Normothermia (38 degrees C) was maintained during ischemia, and rectal temperature was assessed before and after subcutaneous injections. Animals were observed for 96 hours for neurologic evaluation (Tarlov score), and the lumbosacral spinal cord was examined for ischemic damage after perfusion and fixation. Lastly, iNOS protein content was determined using Western blot analysis 48 hours after ischemia in five animals from each group. Neurologic outcome at 96 hours after reperfusion was the same in both groups. The incidence of paraplegia was 67% in the saline-treated group versus 53% in the AG-treated group. No differences in infarction volume, total number of viable motoneurons, or total number of eosinophilic neurons were present between the groups. At 48 hours after reperfusion, iNOS protein content in the spinal cord was increased in one animal in the AG-treated group and in three animals in the control group. The data indicate that peri-ischemic treatment with high-dose AG in rabbits offers no protection against a period of normothermic spinal cord ischemia. There was no conclusive evidence of spinal cord iNOS inhibition after treatment with AG.

Animals↗

PubMed2005

[Laparoscopic rectocele repair with mesh--a case report].

Relaxation of the pelvic floor causes changes in the anatomy. This results in symptoms, which can be treated with different operations. The use of modern, minimal invasive methods and tension free mesh implants for the reconstruction is widely used in rectocele repair as well. We present a 59 year-old patient undergone both vaginal hysterectomy and cystocele repair previously who complained of progressive constipation. Physical examination and dynamic defecography confirmed the presence of a significant rectocele. Anal manometry showed no functional loss. Mobilisation of the rectum and division of the recto-vaginal septum was performed laparoscopically followed by rectopexy and reinforcement of the septum by fixing polypropylene mesh in each position. There was no complication and recovery was fast. Control defecography and functional test one month later did not show pathological findings. One year after surgery the patient is free of complaints or recurrence. In selected patients both laparoscopic approach and mesh implants are safe.

Defecography↗