Hormone responses to a continuous bout of rock climbing in men

Rock climbing is rapidly increasing in popularity as a recreational activity and as a competitive sport. Few studies have tested acute physiological responses to climbing, and no studies to date have tested hormone responses to a climbing-based workout. This study aimed to measure testosterone (T), growth hormone (GH), and cortisol (C) responses to continuous vertical climbing in young male rock climbers. Ten male rock climbers, aged between 21 and 30 years, climbed laps on a submaximal 55' climbing route for 30 min, or until exhaustion, whichever came first. Heart rate (HR) was recorded after every lap. Blood samples were collected by venipuncture before (Pre), immediately post (IP), and 15 min after the climbing exercise (P15) to assess blood lactate and plasma GH, T, and C. Subjects climbed 24.9 ± 1.9 min and 507.5 ± 82.5 feet. Peak HR was 182.1 ± 2.3 bpm, and lactate (Pre: 2.9 ± 0.6 mmol/dL, IP: 11.1 ± 1.0 mmol/dL) significantly (P < 0.05) increased from Pre to IP. T concentrations significantly (P < 0.05) increased from Pre (6.04 ± 0.31 ng/mL) to IP (7.39 ± 0.40 ng/mL) and returned to baseline at P15 (6.23 ± 0.33 ng/mL). Cortisol levels did not significantly change during the protocol. GH significantly (P < 0.01) increased from Pre (0.63 ± 0.17 ng/mL) to IP (19.89 ± 4.53 ng/mL) and remained elevated at P15 (15.03 ± 3.89 ng/mL). An acute, short-term bout of high-intensity continuous climbing was an effective exercise stimulus for elevating plasma testosterone and growth hormone levels in young males.     

Laser Ablation Facilitates Closure of Chronic Enterocutaneous Fistulae

This report describes the use of laser ablation for treatment of chronic enterocutaneous fistulae (ECFs) after failure of conservative therapy. Three patients underwent laser ablation for treatment of 8 ECFs. Mean duration of fistula patency was 28 months with mean fistula output of 134 mL/day. The initial technical success was 100% with no major or minor complications. Three ECFs required repeat treatment. At mean follow-up of 53 days, 7 of the fistulae were occluded. One fistula showed a markedly reduced output of 10 mL/day.     

Transvenous Biopsy in the Diagnosis of Intravascular or Perivascular Neoplasm: A Single-Center Retrospective Analysis of 36 Patients

Between September 2008 and August 2017, 36 patients (mean age 56 y; range, 30–89 y) underwent transvenous biopsy of suspected tumor thrombus or perivascular tumor. Intravascular biopsy was pursued because of inaccessible percutaneous access in 9 patients (25%) and as part of a planned revascularization procedure in 27 patients (75%). Histopathologic results showed malignancy in 26 patients (72%) and benign etiologies in 10 patients (28%). No patients required repeat biopsy. There were no complications related to the biopsy procedure. The present series suggests that transvenous biopsy is a safe and accurate method of intravascular and perivascular mass tissue sampling.     

Gaze during visually-guided locomotion in cats

Visual guidance is often critical during locomotion. To understand how the visual system performs this function it is necessary to know what pattern of retinal image motion neurons experience. If a locomoting observer maintains an angle of gaze that is constant relative to his body, retinal image motion will resemble Gibson's (The Perception of the Visual World (1950)) well-known optic flow field. However, if a moving observer fixates and tracks a stationary feature of the environment, or shifts his gaze, retinal motion will be quite different. We have investigated gaze in cats during visually-guided locomotion. Because cats generally maintain their eyes centered in the orbits, their gaze can be monitored with reasonable accuracy by monitoring head position. Using a digital videocamera, we recorded head position in cats as they walked down a cluttered alley. For much of the time, cats maintained a downward angle of gaze that was constant relative to their body coordinates; these episodes averaged 240 ms in duration and occupied 48-71% of the total trial time. Constant gaze episodes were separated by gaze shifts, which often coincided with blinks. Only rarely did we observe instances when cats appeared to fixate and track stationary features of the alley. We hypothesize that walking cats acquire visual information primarily during episodes of constant gaze, when retinal image motion resembles Gibson's conventional optic flow field.     

1alpha,25-dihydroxyvitamin D(3) (calcitriol) and its analogue, 19-nor-1alpha,25(OH)(2)D(2), potentiate the effects of ionising radiation on human prostate cancer cells

Radiotherapy with external beam radiation or brachytherapy is an established therapeutic modality for prostate cancer. Approximately 30% of patients with localised prostate cancer relapse at the irradiated site. Secondary effects of ionising radiation (IR), for example, bowel and bladder complications, are common. Thus, the search for biological response modifiers that could potentiate the therapeutic effects of radiation and limit the occurrence of serious side effects is an important task in prostate cancer therapy. 1alpha,25-Dihydroxyvitamin D(3) (calcitriol), the active metabolite of vitamin D, and its analogues are under investigation for the treatment of several malignancies including prostate cancer. Here, we report that 1alpha,25-dihydroxyvitamin D(3) and its less calcaemic analogue 19-nor-1alpha,25-(OH)(2)D(2) (Zemplar) act synergistically with IR to inhibit the growth of the human prostate cancer cells in vitro. 1alpha,25-dihydroxyvitamin D(3) potentiated IR-induced apoptosis of LNCaP cells, and nanomolar doses of 1alpha,25-dihydroxyvitamin D(3) and 19-nor-1alpha,25-(OH)(2)D(2) showed synergistic inhibition of growth of LNCaP cells at radiobiologically relevant doses of IR (1-2 Gy). At higher doses of IR, the combination of 1alpha,25-dihydroxyvitamin D(3) and IR or 19-nor-1alpha,25-(OH)(2)D(2) and IR resulted in moderate antagonism. The synergistic effect at radiobiologically relevant doses of radiation suggests that a combination of 1alpha,25-dihydroxyvitamin D(3) or 19-nor-1alpha,25-(OH)(2)D(2) with IR could permit a reduction in the dose of radiation given clinically and thus potentially reduce treatment-related morbidity.     

Congenital and developmental deformities of the spine in children with myelomeningocele

The treatment of spinal deformities in children with myelomeningocele poses a formidable task. Multiple medical comorbidities, such as insensate skin and chronic urinary tract infection, make care of the spine difficult. A thorough understanding of the natural history of these deformities is mandatory for appropriate treatment to be rendered. A team approach that includes physicians from multiple specialties provides the best care for these patients. The two most challenging problems are paralytic scoliosis and rigid lumbar kyphosis. The precise indications for surgical intervention are multifactorial, and the proposed benefits must be weighed against the potential risks. Newer spinal constructs now allow for fixation of the spine in areas previously difficult to instrument. Complications appear to be decreasing with improved understanding of the pathophysiology associated with myelomeningocele.     

Hip fractures: condylocephalic rod versus compression screw

In a series of 70 consecutive patients with nonpathologic intertrochanteric or subtrochanteric hip fractures, the first 35 were treated by a single semi-flexible condylocephalic nail. The second 35 patients were treated by a sliding compression screw and side-plate. The groups were comparable regarding age and intercurrent medical illness. The average anesthesia time and blood loss were nearly the same in each group. The incidence of failure of fracture fixation was high in the group treated by the condylocephalic nail, statistically significant at p less than .001. None of the patients treated by the sliding compression screw and side-plate lost fracture fixation. In this series, condylocephalic nails did not provide good fixation of this type of fracture and did not lessen surgical morbidity.     

The Pathogenesis of Progressive Cavitation of the Spinal Cord

It has been suggested that the pathogenesis of cord cavitation is multifactorial, but that there may be a common mechanism, if not for their actual cause then at least for the increase in size. A case is discussed in which the location of the cavitation suggested the cause was chronic ischemia of vascular origin.     

Spacing of cytochrome oxidase blobs in visual cortex of normal and strabismic monkeys

Some models of visual cortical development are based on the assumption that the tangential organization of V1 is not determined prior to visual experience. In these models, correlated binocular activity is a key element in the formation of visual cortical columns, and when the degree of interocular correlation is reduced the models predict an increase in column spacing. To examine this prediction we measured the spacing of columns, as defined by cytochrome oxidase (CO) blobs, in the visual cortex of monkeys whose binocular vision was either normal or disrupted by a strabismus. The spatial distribution of blobs was examined in seven normal and five strabismic macaques. Tangential sections through the upper layers of the visual cortex were stained to reveal the two-dimensional (2D) pattern of CO blobs. Each blob was localized and their center-to-center spacing, packing arrangement and density were calculated using 2D nearest-neighbor spatial analyses. The mean center-to-center spacing of blobs (590 microm for normally reared and 598 microm for strabismic macaques) and the mean density of blobs (3.67 blobs/mm2 for normally reared and 3.45 blobs/mm2 for strabismic macaques) were not significantly different. In addition, the 2D packing arrangement of the blobs was not affected by strabismus. While it is clear that neural activity plays a key role in the elaboration and refinement of ocular dominance cortical modules, we conclude that it does not determine the spatial period of the pattern of CO blobs. This suggests that aspects of the neural circuitry underlying the columnar architecture of the visual cortex are established prenatally and its fundamental periodicity is not modifiable by experience.