Dorsal Lumbar Region Research Articles

Ankylosing Spondylitis and Autoimmune Thrombocytopenia: the First Senegalese Case

Introduction: Ankylosing spondylitis (AS) and autoimmune thrombocytopenia are two distinct diseases, and they can occur rarely. Objective: To determine the epidemiological, clinical, therapeutic profiles and impact of this rare association in the literature Observation: This was a 57-year-old teaching patient received on September 07, 2020. The examination of the musculoskeletal system revealed lumbar pain. The onset was 26 years ago and was marked by the progressive onset of pain located in the dorsal spine, lumbar and manubrio-sternal region, then a progressive extension to both wrists and the left knee with a VAS of 6/10. Associated signs were stiffness and synovitis of the left knee. The biology showed a non-specific biological inflammatory syndrome with accelerated blood pressure at 70 minutes in the first hour and CRP increased to 15 mg/l, normocytic normochromic anemia (hemoglobin 7.6 g/dl), thrombocytopenia at 51,000/mm3 (N : leukopenia at 3,100/mm3 and neutropenia at 1115/mm3 (pancytopenia). The transaminases ALAT was 60 IU/L and Gamma GT was increased to 265 IU/L, the immunological tests were negative with the presence of the HLA B27 positive antigen, and the fixed anti-platelet antibodies showed the presence of fixed autoantibodies directed against the glycoprotein complex IIb and IIIa and the absence of circulating antibodies directed against the glycoprotein complexes IaIIb, IIbIIIa and IbIX. The lumbar CT scan shows syndesmophytes and osteophytes (Fig 2) and the CT scan of the pelvis shows Forestier stage III sacroiliitis (Fig 1). Conclusion: The association of ankylosing spondylitis and autoimmune thrombocytopenia is rare but possible, and should be considered whenever a known spondyloarthritis patient presents with a platelet collapse. Treatment with methotrexate and anti-inflammatory drugs may be effective in some cases.

Analysis of the Different Lymphatic Drainage Patterns during Sentinel Lymph Node Biopsy for Skin Melanoma

In the last two decades, studies of lymphoscintigraphy imaging in lymphatic mapping reported an extreme heterogeneity of skin lymphatic drainage of some skin area, in contrast with the previous scientific literature. The aim of this study was to investigate the presence of any correlations between the topographical location of cutaneous melanoma and the topographical location of sentinel lymph nodes. Data from 165 patients undergoing sentinel lymph node biopsy between January 2013 and May 2021 were analyzed, demonstrating that melanomas in the Lumbar region presented a significant more heterogeneous drainage by site than those in the Scapular region (p < 0.01) and that melanomas in the Subscapular region were significantly more heterogeneous by laterality (unilateral vs. bilateral) than those in the Scapular region (p < 0.05). Results of this study supported the evidence of multiple lymphatic drainage as regards the sentinel node biopsy performed in skin melanoma located on the dorsal subscapular region and lumbar region. For this reason, the association of preoperative lymphoscintigraphy with another imaging evaluation is needed in these critical cutaneous areas. Recent technical developments enabling fluorescence lymphography together with indocyanine green have significantly improved the visualization of lymphatic drainage patterns at a microscopic level. In the preoperative phase, any doubt can be resolved by associating the SPET-CT scan to lymphoscintigraphy, while during the intraoperative phase, an additional evaluation with indocyanine green can be performed in doubtful cases. The aim of the duplex lymphatic mapping (pre and/or intraoperative) is an accurate search of sentinel nodes, in order to reduce the rate of false negatives.

Mechanically stimulating the lumbar region inhibits locomotor-like activity and increases the gain of cutaneous reflexes from the paws in spinal cats.

Mechanically stimulating the dorsal lumbar region inhibits locomotion and reduces weight support during standing in rabbits and cats. However, how this inhibitory effect from the lumbar skin is mediated is poorly understood. Here we evaluated the effect of mechanically stimulating (vibration or pinch) the dorsal lumbar region on short-latency (8- to 13-ms onset) cutaneous reflex responses, evoked by electrically stimulating the superficial peroneal or distal tibial nerves, in seven adult cats with a low thoracic spinal transection (spinal cats). Cutaneous reflexes were evoked before, during, and after mechanical stimulation of the dorsal lumbar region. We found that mechanically stimulating the lumbar region by vibration or manual pinch abolished alternating bursts of activity between flexors and extensors initiated by nerve stimulation. The activity of extensor muscles was abolished bilaterally, whereas the activity of some ipsilateral flexor muscles was sustained during vibration/pinch. Mechanically stimulating the lumbar region increased ipsilateral and contralateral short-latency excitatory responses evoked by cutaneous inputs, a phenomenon that was generalized to muscles crossing different joints and located in different limbs. Our results indicate that the inhibitory effect on locomotion and weight support is not mediated by reducing cutaneous reflex gain and instead points to an inhibition of central pattern-generating circuitry, particularly the extensor component. The results provide greater insight into interactions between different types of somatosensory inputs within spinal motor circuits.NEW & NOTEWORTHY Vibration or pinch of the lumbar region in spinal-transected cats abolished alternating bursts of activity between flexors and extensors initiated by nerve stimulation. Mechanically stimulating the lumbar region increased ipsilateral and contralateral short-latency excitatory responses evoked by cutaneous inputs in hindlimb muscles. Sensory inputs from mechanoreceptors of the lumbar region do not mediate their inhibitory effect on locomotion and weight support by reducing the gain of short-latency excitatory cutaneous reflexes from the foot.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P3. Recruitment of mesenchymal stem cells to the intervertebral disc via local chemokine delivery from an injectable hydrogel

BACKGROUND CONTEXT Biologic-based therapies for inhibiting or reversing intervertebral disc (IVD) degeneration have garnered considerable interest, however obtaining a stem cell source remains a resource-intensive hurdle. Strategies to recruit endogenous mesenchymal stem cells (MSCs) to the IVD would assist in circumventing these hurdles. PURPOSE The purpose of this study is to evaluate the ability of three homing chemokines to recruit marrow-derived MSCs to the IVD. METHODS Under IACUC approval, 24 female Lewis rats (n=6/group) underwent anterior, transperitoneal L5/L6 intradiscal injection of hydrogel containing homing chemokine (SDF-1, RANTES, or MCP-1) or hydrogel alone (control). Immediately postop, all rats were administered 1×107 MSCs labeled with CellVue Burgundy, via tail vein injection. In vivo near-infrared (NIR) fluorescence imaging was used to longitudinally track MSC migration to L5/L6 at 1, 2, 7, and 14days postinjection. At each time point, the dorsal lumbar region was shaved to minimize hair-related auto-fluorescence, rats were positioned prone on an imaging bed and NIR fluorescence imaging of the dorsal lumbar region was conducted at 700 nm. Following euthanasia at 14days, the lumbar spine was harvested, dissected, and the anterior aspect was re-imaged using 700 nm NIR. A consistently sized, circular region-of-interest was placed over L5/L6 and mean signal intensity was computed. In vivo and ex vivo imaging were normalized to skin and the L3/L4 disc, respectively, to account for nonspecific signal. Mean signal intensity of chemokine groups was compared to the control group using one-way ANOVA. Post-hoc tests were conducted using the Dunnett correction for multiple comparisons, and all reported P-values are compared to the control group. RESULTS Longitudinal in vivo NIR demonstrates measurable fluorescent signal at L5/L6 at 1day (control: 0.005±0.007, SDF-1: 0.008±0.008, P=0.918; RANTES: 0.017±0.011, P=0.074; MCP-1: 0.007±0.009, P=0.990); however, no significant differences were noted between groups. NIR signal was indistinguishable from skin at 3, 7, and 14day time points for all groups. Ex vivo NIR signal was appreciable at the L5/L6 disc level in all treatment groups, indicating successful migration of tagged MSCs to the target disc. RANTES and MCP-1 treatment groups exhibited significantly higher ex vivo signal compared to control (control: 0.0017±0.0006, SDF-1: 0.0025±0.0003, P=0.054; RANTES: 0.0030±0.0006, P=0.001; MCP-1: 0.0026±0.0006, P=0.017). CONCLUSIONS Following intra-discal injection, in vivo imaging demonstrates early recruitment of labeled MSCs to the L5/L6 IVD, with chemokine groups exhibiting anecdotally higher signal compared to control. Appreciable in vivo signal was only detected at 24hours, suggesting that the highest localization of MSCs to the L5/L6 disc level occurs acutely. Ex vivo imaging, which allows the removal of extraneous tissue and allows antero-posterior image acquisition, revealed notable fluorescent signal at L5/L6, demonstrating retention of labeled MSCs at the L5/L6 IVD at 14days following chemokine injection. Specifically, RANTES was most effective at recruiting MSCs to the IVD compared to control groups and will be used in future studies characterizing therapeutic effects of recruited MSCs in the setting of IVD degeneration. Ongoing histologic analysis will localize tagged cells within specific tissues.

Hyaluronidase administered with xylazine–tiletamine–zolazepam into adipose tissue shortens recovery from anesthesia in pigs

ObjectiveTo evaluate the effect of hyaluronidase on uptake, duration and speed of elimination of xylazine–tiletamine–zolazepam administered in the subcutaneous fat over the dorsal lumbar region of swine. Study designBlinded, randomized, crossover study. AnimalsSix healthy Landrace/Large White pigs weighing 132±24 kg (mean±standard deviation). MethodsAnimals were administered xylazine (1 mg kg−1) and tiletamine–zolazepam (8 mg kg−1) (control treatment, CON), or xylazine–tiletamine–zolazepam at the same doses with hyaluronidase (400 IU) (treatment HYA). The treatments were administered into the dorsal lumbar adipose tissue, 2.5–3.0 cm laterally from the spinous process of the second lumbar vertebra. The latency, anesthesia and recovery periods were measured. Heart rate, noninvasive systolic, diastolic, and mean arterial pressures, respiratory rate, hemoglobin oxygen saturation and rectal temperature were recorded every 10 minutes for up to 50 minutes. ResultsOne animal in CON and one animal in HYA were responsive to stimulation and did not allow safe handling. No significant difference was found between treatments for latency (CON 11.3±5.9 minutes, HYA 7.4±5.1 minutes) and anesthesia (CON 53±53 minutes, HYA 49±38 minutes) periods. Recovery period was shorter in HYA (9±6 minutes) than in CON (32±16 minutes) (p < 0.05). Physiological variables were not significantly changed over time and were within accepted normal clinical limits for the species in both treatments. Conclusion and clinical relevanceHyaluronidase (400 IU) administered into adipose tissue in pigs did not reduce the latency and duration of dissociative anesthesia, but was associated with faster recovery.

Reconstructive Surgical Repair of a Forth Degree Iatrogenic Burn in a Dog

Background: Burns are uncommon in small animal surgery routine and represents a real therapeutic challenge. Skin can be affect in different degrees of deepness as superfcial, partial thickness, full thickness and full thickness affecting underlying tissues. Each degree has individual features. Progression through degrees can occur in the frst 24 h or if treatment is inadequate. This paper aims to describe therapeutic approach and surgical technique to treat a huge dorsal iatrogenic thermal burn injury. Case: A 4-year-old female German Shepard was referred to veterinary hospital after 11 days of elective ovariosalpingohisterectomy. The patient presented a severe skin injury with crusts, eschars, purulent discharge and myiasis on dorsal cervical, thoracic and lumbar region. Beside severity of the wound, animal present good general status and normal vital signs. Complete blood count and biochemical analysis were within normal ranges. Histopathologic analysis of a wound tissue sample revealed the presence of coagulation necrosis and inflammatory response. The absence of traumatic events, histopathologic result and wound features increased suspicious of an iatrogenic burn injury from a poorly regulated thermal mattress used during surgical intervention. “Rule of Nines” was estimated as 25% of total body surface area. Systemic antibiotics and topical treatment with 0.05% chlorhexidine digluconate and 2.5% silver sulfadiazine ointment followed by wet-wet bandage was performed after initial surgical debridement. Muscle and vertebral bone explosion were evident. Topical treatment with Silver Sulfadiazine and chlorhexidine persisted twice daily until granulation tissue formation. Pain killers and sedation were often necessary during bandage changes. At 65th day proceeded to en bloc excision of scar tissue and surgical reconstruction with skin advancement and recruitment technique. Tie-over dressing was applied to cover the fnal wound. After 14 days animal received hospital discharge, and was assessed bi-weekly for 60 days. Discussion: Besides great extension of the burn injury, patient’s age, absence of systemic involvement and fluid therapy or critical care the prognosis was good. Modifed “rule of nine” are used to estimate wound size in dogs. The wound was classifed as forth degree or full thickness injury due to exposed muscular layer and bone. Early debridement, standard topical and systemic treatment protocol applied granted good recovery of wound bed. Due to be uncommon in small animal routine, main diagnosis and therapeutic recommendations for veterinary patients are based on human data. Systemic antimicrobial drugs are usually not recommended due to low concentration in burned tissues, however, prophylactic use was necessary due to highly infected tissues and possible bacterial absorption from devitalized tissues. Delayed primary closure technique was necessary due to highly infection site and extension, which turns surgical approach hard to perform. After formation of a granulation tissue bed for wound reconstruction, surgical treatment was performed. Surgical reconstruction is indicated in large full thickness defects and for better cosmetic appearance. The correct use and regulation of thermal mattress can avoid burns that can be life threatening. This case report rises the important concept that even low contact temperatures when persistent for long time can cause burn injuries. Keywords: thermal, mattress, injury, dogs, plastic.

The critical role of spinal 5-HT7 receptors in opioid and non-opioid type stress-induced analgesia

The opioid and non-opioid types of stress-induced analgesia have been well defined. One of the non-opioid type involve the endocannabinoid system. We previously reported that the spinal serotonin 7 receptor (5-HT7) blockers inhibit both morphine and cannabinoid-induced analgesia, thus we hypothesized that descending serotonergic pathways-spinal 5-HT7 receptor loop might contribute to stress-induced analgesia.Stress-induced analgesia was induced with warm (32°C) or cold (20°C) water swim stress in male Balb-C mice. The effects of intrathecal injection of a selective 5-HT7 receptor antagonist, SB 269970, of the denervation of serotonergic neurons by intrathecal administration of 5,7-dihydroxytryptamine (5,7-DHT) and of lesions of the dorsolateral funiculus on opioid and non-opioid type stress-induced analgesia were evaluated with the tail-flick and hot plate tests. The expression of 5-HT7 receptors mRNA in the dorsal lumbar region of spinal cord were analyzed by RT-PCR following spinal serotonin depletion or dorsolateral funiculus lesion. The effects of the selective 5-HT7 receptor agonists LP 44 and AS 19 were tested on nociception.Intrathecal SB 269970 blocked both opioid and non-opioid type stress-induced analgesia. Dorsolateral funiculus lesion or denervation of the spinal serotonergic neurons resulted in a marked decrease in 5-HT7 receptor expression in the dorsal lumbar spinal cord, accompanied by inhibition of opioid and non-opioid type stress-induced analgesia. However, the systemic or intrathecal LP 44 and AS 19 alone did not produce analgesia in unstressed mice.These results indicate that descending serotonergic pathways and the spinal 5-HT7 receptor loop play a crucial role in mediating both opioid and non-opioid type stress-induced analgesia.

A guanine-ethylthioethyl-glutathione adduct as a major DNA lesion in the skin and in organs of mice exposed to sulfur mustard

Sulfur mustard (SM) is an old chemical warfare but it remains a threat to both militaries and civilians. SM mainly targets skin, eyes and lungs and diffuses to internal organs. At the molecular level, SM is able to damage DNA through the formation of monoadducts and biadduct. Glutathione (GSH) is another critical target of SM in cells since it is part of the detoxification mechanism against alkylating agents. In the present work, we investigated whether SM could form covalent bonds simultaneously with a DNA base and the sulfhydryl group of GSH. The expected guanine adduct, S-[2-(N7-guanyl)-ethylthioethyl]-glutathione (N7Gua-ETE-GSH), was synthesized and detected in several tissues of SKH-1 mice exposed to 60mg/kg of SM in the dorsal-lumbar region. N7Gua-ETE-GSH was detected in all organs studied, except in the liver. The tissue exhibiting the highest levels of N7Gua-ETE-GSH was skin, followed by brain, lungs, kidneys and spleen. N7Gua-ETE-GSH was detected in skin, brain and lungs as long as two weeks after exposure. The persistence was less in other organs. The observation of the formation of N7Gua-ETE-GSH in vivo confirms the variety of damages induced by SM in DNA. It also provides another example of the formation of DNA adducts involving glutathione following in vivo exposure to bifunctional alkylating compounds.

Histomorphometric Analysis and Regional Variations of Full Thickness Skin Grafts in Dogs

To (1) compare thickness of the epidermis and dermis of anatomically different donor sites in dogs, and (2) evaluate hair follicle damage during full thickness skin grafts (FTSG) preparation from anatomically different donor sites. Another objective was to compare the extent of agreement between gross and histologic quality of graft preparation. Ex vivo study. Healthy Beagle dogs (n = 12). Skin samples were harvested from fresh cadavers free of gross dermatopathology and FTSG prepared. Regional, epidermal and dermal thickness, and hair follicle density in intact skin and FTSG specimens from different regions were determined by histomorphometric analysis. Hair follicle density in intact skin and FTSG specimens, and skin thickness measurements were compared among regions. Mean epidermis and dermis thickness of the dorsal lumbar and lateral neck regions were significantly greater when compared with other sites. Total hair follicle (superficial and deep dermis) densities were significantly less in prepared FTSG versus intact skin specimens. The dorsal lumbar region had the highest hair follicle density. Thickness of the epidermis and dermis is dependent on body region. Hair follicle density in the FTSG specimens was decreased compared with intact skin specimens, which may affect hair regrowth in FTSG.

Patient with perforation caused by emphysematous cholecystitis who showed flare on the skin of the right dorsal lumbar region and intraperitoneal free gas

We report an 84-year-old man with perforation caused by emphysematous cholecystitis who showed flare on the skin of the right dorsal lumbar region and intraperitoneal free gas. The patient was admitted for abdominal pain, abdominal swelling, and consciousness disorder 18 days after the onset. Abdominal computed tomography (CT) revealed emphysema in the gallbladder and a small amount of intraperitoneal free gas. Intraoperative findings suggested gangrenous cholecystitis. The gallbladder wall was perforated, and an abscess involving the right subphrenic region, the periphery of the liver and gallbladder, and the right paracolonic groove, was detected. The flare on the body surface may have reflected abscess formation in the right abdominal cavity. Emphysematous cholecystitis induces necrosis and perforation in many patients, and immediate strategies such as emergency surgery are important.

Cutaneous metastasis of primary appendicular osteosarcoma in a dog

A 6-year-old, neutered male Rottweiler was presented to the University of Illinois Veterinary Teaching Hospital because of a lytic bone lesion involving the distal portion of the right radius and possible pulmonary metastases on thoracic radiographs. Results of serum biochemical analysis were unremarkable. Aspiration and cytologic examination of the bone lesion indicated likely sarcoma with reactive bone. Cutaneous masses were found on the left thigh, interscapular region, and dorsal lumbar region, 4 weeks after initial presentation. Neoplastic spindle cells were found in aspirates from 2 of the masses. The neoplastic cells stained positive for alkaline phosphatase activity using cytochemistry. Re-evaluation of serum biochemical values at this time revealed a marked increase in alkaline phosphatase activity (413 U/L, reference interval 12-110 U/L) compared with the initial value (26 U/L). Due to progressive disease, the dog was euthanized and a necropsy was performed. Histologic findings included primary osteosarcoma of the distal portion of the right radius, with metastases in the lungs, spleen, left fourth and fifth ribs, soft tissue of the right medial thigh, and T1-T3/interscapular region. Cutaneous metastasis of primary appendicular osteosarcoma has been reported rarely in animals and humans. Increased serum alkaline phosphatase activity may be a potential indicator of poor prognosis for this neoplasm.

Cytological evaluation of the tissue–implant reaction associated with subcutaneous implantation of polymers coated with titaniumcarboxonitride in vivo

The aim of the present study was to evaluate the influence of titanium-coated polymers on the inflammatory response and remodeling of connective tissue during wound-healing processes. Discs of polyethyleneterephthalate (PET) and silicone as well as high-weight meshes of polypropylene (PP) were coated with a titaniumcarboxonitride (Ti(C,N,O)) layer by a plasma-assisted chemical vapor deposition process (PACVD) and implanted subcutaneously in the dorsal lumbar region of Wistar rats. Light microscopic and histological evaluation of capsule thickness, capsule quality, implant–tissue interface and collagen composition was performed 7, 14, 21 and 28 days post-operatively. All implants were surrounded by a fibrous capsule with decreasing thickness after 2–4 weeks post-implantation. Titaniumcarboxonitride-coated polymers showed no significant differences in capsule thickness and inflammatory cellular response. An increased collagen type III/I ratio, especially for titaniumcarboxonitride-coated materials, was found in week one after implantation remaining elevated up to week 4. This might be associated with disordered collagen metabolism and immature scar reaction. In contrast to previous in vitro experiments, Ti-coating of polymers did not improve biocompatibility after subcutaneous implantation in rats. Material reduction to low-weight meshes and enlargement of pore size may demonstrate a benefit of Ti-coated meshes with an increased biocompatibility.

Melanocyte and gonad activity as potential severity modifying factors in C3H/HeJ mouse alopecia areata.

Circumstantial evidence has previously suggested gonad derived steroid hormones and melanogenesis related antigens may modify human alopecia areata (AA). AA-like hair loss can be induced in C3H/HeJ mice after skin allografts from spontaneous AA-affected mice. This inducible model was used to evaluate hormones and hair follicle melanocyte presence as disease-severity modifiers. Ten females and 9 males were gonadectomized and received AA-affected allografts. All gonadectomized mice had 2-4 weeks delay in AA onset relative to non-gonadectomized controls. Two females and 4 males failed to develop any AA by 25 weeks after grafting. The experiment was repeated with gonadectomized female and male mice plus non-gonadectomized mice subcutaneously implanted with silastic capsules containing 80 microg 17beta estradiol or 10 mg 5alpha dihydrotestosterone, respectively. Five of 11 ovariectomized and 9 of 11 non-ovariectomized, estradiol supplemented females developed AA with extremely rapid progression. Three of 8 castrated, but none of 11 non-castrated, dihydrotestosterone-supplemented males expressed AA. In a separate study, 14 mice were freeze-branded, producing white hair on the dorsal lumbar region, and later received full-thickness allografts. Thirteen mice developed patchy pigmented and non-pigmented hair loss. One mouse developed diffuse, pigmented hair loss, but with white hair survival persisting 25 weeks after grafting. The results suggest that gonadal steroid hormones can modulate C3H/HeJ mouse AA where estradiol promoted rapid progression of AA while dihydrotestosterone increased resistance to AA onset. In general, both pigmented and non-pigmented C3H/HeJ mouse hair is susceptible to AA. Murine AA susceptibility and severity clearly involves an interplay between genetic and epigenetic factors.

The determination of draining lymph node cell cytokine mRNA levels in BALB/c mice following dermal sodium lauryl sulfate, dinitrofluorobenzene, and toluene diisocyanate exposure.

Differential modulation has been demonstrated in interleukin-4 (IL-4), IL-10, and interferon gamma (IFN-gamma) mRNA and protein secretion patterns of cells isolated from the draining lymph nodes of mice following exposure to T cell and respiratory sensitizers. Using a multiprobe ribonuclease protection assay, the following investigation examined the mRNA expression patterns of multiple cytokines associated with respiratory sensitization for modulation following exposure to chemicals known primarily to induce irritation (sodium lauryl sulfate), respiratory sensitization (toluene diisocyanate), or T cell-mediated hypersensitivity (dinitrofluorobenzene) responses. On days 0 and +5 female BALB/c mice were exposed to either test article or vehicle on the shaven dorsal lumbar region; on days +10 through +12 the mice received test article on the dorsal aspect of each ear. On day +13 animals were euthanized, draining lymph nodes were excised, and mRNA was isolated immediately or following 24 or 48 h of culture in the presence or absence of concanavalin (Con) A. Differential expression of cytokine mRNA was most notable following 24 h incubation with Con A. Modulation of IL-4, -10, and IFN-gamma following chemical exposure was consistent with previous studies. In addition, IL-9, -13, and -15 were significantly elevated only following toluene diisocyanate exposure. Further investigations of these cytokines may provide additional insight into the mechanisms of chemically induced respiratory sensitization and provide endpoints for the detection of a chemical's ability to elicit IgE-mediated hypersensitivity responses.

Diagnostic imaging of foreign body reactions in dogs with diffuse back pain.

Six hunting dogs were investigated after showing signs of diffuse back pain. In three of the dogs, prodromal signs included coughing. Swelling in the dorsal lumbar region was noted in four of the dogs, but in two there was no visible or palpable swelling. Initial radiographs of the lumbar region were normal in two of the dogs and showed mild to moderate ventral periosteal reactions in the L1 to L4 region in the remaining four. On ultrasonography and magnetic resonance imaging, changes were seen in the sublumbar muscles (e.g., abnormal echogenicity and increased signal intensity) in five dogs examined. Exploratory surgery revealed plant material foreign bodies in the sublumbar muscles in the L1 to L4 region in five of the six dogs. The concurrent infections were caused predominantly by anaerobic bacteria common to the mucous membranes of the oropharyngeal and respiratory tracts. All dogs recovered, with restored hunting ability. The mean follow-up period was five years (range 1.3 to 7.8 years). It is proposed that the plant parts were inhaled, and then migrated along either diaphragmatic crus to lodge in the sublumbar muscles.

Lumbar dura mater biomechanics: experimental characterization and scanning electron microscopy observations.

There is no consensus about the anatomical structure of human dura mater. In particular, the orientation of collagen fibers, which are responsible for biomechanical behavior, is still controversial. The aim of this work was to evaluate the mechanical properties and the microstructure of the lumbar dura mater. We performed experimental mechanical characterization in longitudinal and circumferential directions and a scanning electron microscopy observation of the tissue. Specimens of human dura mater were removed from the dorsal-lumbar region (T12-L4/L5) of six subjects at autopsy; specimens of bovine dorsal-lumbar dura mater were obtained from two animals at slaughter. Human and bovine tissues both exhibited stronger tensile strength and stiffness in the longitudinal than in the circumferential direction. Scanning electron microscopy observations of dura mater showed that the collagen fibers are mainly oriented in a longitudinal direction, which accounts for its stronger tensile strength in this direction. We conclude that dura mater has a different mechanical response in the two directions investigated because the fiber orientation is predominantly longitudinal. In this experimental work, we studied the structural and functional relationship of human lumbar dura mater. We performed mechanical tests and microscopic observations on dura mater samples. The results show that the dura mater is mainly composed of longitudinally oriented collagen fibers, which account for higher tissue resistance in this direction.

Lumbar Dura Mater Biomechanics

There is no consensus about the anatomical structure of human dura mater. In particular, the orientation of collagen fibers, which are responsible for biomechanical behavior, is still controversial. The aim of this work was to evaluate the mechanical properties and the microstructure of the lumbar dura mater. We performed experimental mechanical characterization in longitudinal and circumferential directions and a scanning electron microscopy observation of the tissue. Specimens of human dura mater were removed from the dorsal-lumbar region (T12-L4/L5) of six subjects at autopsy; specimens of bovine dorsal-lumbar dura mater were obtained from two animals at slaughter. Human and bovine tissues both exhibited stronger tensile strength and stiffness in the longitudinal than in the circumferential direction. Scanning electron microscopy observations of dura mater showed that the collagen fibers are mainly oriented in a longitudinal direction, which accounts for its stronger tensile strength in this direction. We conclude that dura mater has a different mechanical response in the two directions investigated because the fiber orientation is predominantly longitudinal.In this experimental work, we studied the structural and functional relationship of human lumbar dura mater. We performed mechanical tests and microscopic observations on dura mater samples. The results show that the dura mater is mainly composed of longitudinally oriented collagen fibers, which account for higher tissue resistance in this direction.

Effect of dietary selenium and magnesium on human mammary tumor growth in athymic Nude Mice

The effect of dietary selenium (Se) supplementation and low dietary magnesium (Mg) on growth of cells of the human mammary tumor cell line (HTB123/DU4475) and the tissue glutathione (GSH) content in female athymic nude mice was studied. Sixty three- to four-week-old female athymic nude mice were randomly divided into six dietary groups of 10 animals. The mice were fed a modified AIN-76A diet with two levels of Mg (100 and 665 mg/kg) and three levels of Se (0.04, 0.2, and 4.0 mg/kg). At the fourth week of dietary treatment, mice were subcutaneously inoculated with 2.5 x 10(6) viable tumor cells on the dorsal lumbar region and then fed their respective diets for another four weeks. Dietary Se supplementation had no significant effect on tumor growth or tissue GSH content. Low dietary Mg limited both tumor growth and tissue GSH synthesis but raised Mg and GSH levels in tumor tissues. The growth of mice fed the diet containing 100 mg/kg Mg and 4.0 mg/kg Se was significantly retarded. This study demonstrated that neither Se deficiency nor Se supplementation had any effect on mammary tumor growth or tissue GSH content in athymic nude mice. Low dietary Mg did retard tumor growth and inhibited GSH synthesis. Low dietary Mg also resulted in an apparent increase in Se toxicity in these animals.

Sequelae from radiotherapy in the soft tissues of the pelvic abdominal wall and of the dorsal-lumbar region. (Italian)

Sequelae from radiotherapy in the soft tissues of the pelvic abdominal wall and of the dorsal-lumbar region. (Italian)

A Medicolegal Encounter In Maryland

To the Editor.— A matter of great importance to the Medical and Legal community in Maryland came about during the first week of December 1974. The precedent it so nearly established raises great fear in my mind as to how state power and arrogance can infringe on the rights of members of its citizenry. The story started Oct 15, when a baby girl was born in Holy Cross Hospital, in Silver Spring, Md. The child was the second child to a young, intelligent, professional couple, but was born with severe birth defects—a widely opened and uncovered meningomyelocele or rachischisis in the dorsal-lumbar region, severe clubbing of the feet and deformity of the long bones of both lower extremities, genu recurvatum, no movement or sensation below the waist, and no bladder or bowel control. In addition to this, there was evidence of a beginning hydrocephalus. The pediatrician called in for consultation