Effect of feeding histidine and ß-alanine on carnosine concentration, growth performance, and meat quality of broiler chickens.

The high growth rates of modern broiler breeds increased the risk for novel breast muscle myopathies as serious quality issue, relevant for the industry. In affected muscles, a depletion of the dipeptides carnosine and anserine was reported. Therefore, this study was performed to test whether a supplementation of the precursors histidine and ß-alanine, alone or in combination can increase the dipeptide content in the breast muscle and improve meat quality. Ross 308 broiler chickens were supplemented with 3 different histidine:lysine ratios (0.44, 0.54, 0.64) of standardized ileal digestible amino acids (SID) combined with 0 or 0.5% ß-alanine in total. The birds' performance was recorded at different ages: birds were slaughtered in 2 batches after 33 and 53 d of life. Meat quality was tested at different time points after slaughter on breast fillets stored aerobically. The concentration of the dipeptides and amino acids in blood plasma and muscle tissue was tested postmortem at 35 and 54 d. All performance and meat quality data, as well as peptide and amino acid concentrations, of the 2 × 2 × 3 randomized block design were analyzed separately for the influence of both supplements and for slaughter age. Moreover, the influence of storage time was analyzed separately for meat quality parameters. At both slaughter ages, lesser feed intake (P ≤ 0.005) and breast yield (P ≤ 0.05) were observed in the birds receiving ß-alanine. A greater SID histidine:lysine ratio increased the carnosine concentrations in blood plasma (P < 0.001) and in skeletal muscle (P < 0.001), whereas ß-alanine increased carnosine in plasma at 35 d only (P = 0.004). Anserine was increased in plasma and muscle of older birds (P = 0.003), whereas carnosine was reduced in muscle tissue (P < 0.001). The main impact on meat quality parameters was seen for the age of the birds and storage time of the fillets. In conclusion, the supplementation of histidine increased carnosine in breast muscle but both supplements showed only minor effects on meat quality.

Astroblastoma. Case report, review of the literature, and analysis of treatment strategies.

Astroblastoma, a unique glial tumor, has been described in the literature in case reports and small series. Its rarity has prevented evidenced-based treatment stratification. An 8-year-old boy presented with signs and symptoms of raised intracranial pressure. Imaging studies of the brain demonstrated a large heterogeneously enhancing solid mass in the left frontal lobe with punctate calcifications and cystic components that created subfalcine and uncal herniation. After tumor resection, histological diagnosis revealed a high-grade cerebral astroblastoma. The child's postoperative recovery was complicated by hydrocephalus that necessitated placement of a ventriculoperitoneal shunt. Fifty-four months after undergoing gross total resection and adjuvant radiation therapy, the patient, now 12-years-old, remains tumor free and neurologically stable. Chemotherapy was reserved in the event of tumor recurrence. Since the first description of astroblastoma, its histopathological and clinical features have been debated. We review the histology, immunohistochemistry, and cytogenetics of astroblastoma as well as examine the current literature and treatment strategies for the management of both low and high-grade tumors. Continued clinical studies and longer patient follow-up with a tumor based registry would further clarify optimal treatment for this rare tumor.

Spinal cord injury in a 14-year-old male secondary to cervical hyperflexion with exercise.

STUDY DESIGN: Case report. OBJECTIVES: To present an interesting case of a 14-year-old male with acute paresis of upper extremities and progressive difficulty with lower extremities. The patient is a competitive wrestler and was performing his daily abdominal workout 'sit-ups' with hands interlocked behind his head. During the end and immediately following his abdominal workout, he felt progressive weakness in his upper extremities. He was rushed to the hospital within an hour and seen in the emergency room and admitted to the neurology service for a presumed thromboembolic event. SETTING: New York, USA. RESULTS: The patient was negative for any hematologic disease or coagulopathy. Magnetic resonance imaging was negative for any mass effect on the spinal cord and neurological examination revealed bilateral upper extremity paraparesis 3/5 and lower extremity spasticity and propioceptive dysfunction. The patient was treated with corticosteroids and rigid collar, follow-up examination at 3 months revealed resolution of symptoms. DISCUSSION/CONCLUSION: The pathophysiology of central cord syndrome is thought to be primarily secondary to a hyperextension injury, which causes buckling of the ligamentum flavum and increasing spinal cord diameter which leads to cord compression. This syndrome is more commonly seen in the spondylotic elderly. This case involves a teenager with normal canal diameter; however, combining aggressive exercise with extreme cervical hyperflexion, one can plausibly account for an acute ischemic event or repetitive microinjury to the spinal cord.

Failure rate of frontal versus parietal approaches for proximal catheter placement in ventriculoperitoneal shunts: revisited.

Early studies on ventriculoperitoneal shunt malfunctions demonstrated that proximal catheter obstruction was the most common cause for shunt malfunction and choroid plexus was the primary culprit for catheter obstruction. Subsequently, several studies were performed using stereotactic and endoscopic guidance systems to assist with optimal placement of proximal shunt catheters. Surgeons collectively agree that optimum placement of the proximal catheter tip is away from choroid plexus in the frontal horn. To achieve this catheter placement, neurosurgeons typically choose a frontal or parietal approach. Two previous studies comparing parietal and frontal shunt failure rates in the pediatric population have different conclusions. Thus, we decided to compare proximal catheter failure rates of frontal versus parietal approaches on 117 patients (ages ranging from 1 month to 80 years) who had undergone ventriculoperitoneal shunt placement at our institution. Statistical analysis demonstrated a significantly higher malfunction rate in the patients less than 3 years of age and a lower overall malfunction rate in patients shunted for normal pressure hydrocephalus. Surprisingly, there was no significant difference between the two surgical approaches. Thus, we concluded after reviewing the literature, that regardless of the initial surgical approach, the most important variable in shunt malfunction appears to be the final destination of the catheter tip in relation to the choroid plexus.

Intramedullary inflammatory mass dorsal to the Klippel-Feil deformity: error in development or response to an abnormal motion segment?

STUDY DESIGN: Case study on a 45-year-old female with progressive weakness and paresthesias in her lower extremities and a magnetic resonance image of an intramedullary mass at the level of C5-6 and a Klippel-Feil (KF) deformity ventral to the lesion. OBJECTIVE: Present an interesting case of an intramedullary mass coexisting with a ventral KF deformity with review of the medical literature on intramedullary masses and cervical spine biomechanics. SETTING: New York city, New York, USA. METHODS: Case study with discussion of neurosurgical and neuropathological findings and review of the literature. RESULTS: The patient underwent open neurosurgical excisional biopsy of the intramedullary mass which revealed a non-neoplastic inflammatory mass that slowly resolved with medical management. CONCLUSIONS: While no definitive etiology was found in this case we offer two interesting mechanisms: (1) maldevelopment of the cervical spine or (2) this inflammatory mass is in response to an abnormal motion at the level of the Klippel-Feil.

A prospective analysis of the use of octylcyanoacrylate tissue adhesive for wound closure in pediatric neurosurgery.

OBJECTIVE: Cyanoacrylate monomers have been developed for use as skin adhesives. Previous studies have demonstrated that using this skin adhesive for the closure of traumatic lacerations results in excellent cosmesis, decreased procedure-related pain and timesavings. SURGICAL TECHNIQUE: Octylcyanoacrylate skin adhesive is applied after the placement of deep fascial sutures with close approximation of the skin edges. The adhesive is applied in liquid form and polymerizes rapidly to solid form. Multiple layers are applied forming a hard impenetrable barrier. RESULTS: This technique was prospectively evaluated in the closure of 102 elective neurosurgical operations with 142 incisions: ventriculoperitoneal shunt insertion/revision (53%) and craniotomy for tumors (10%) were the commonest procedures. There were a total of 83 scalp, 36 abdominal, 8 neck, 6 chest and 6 lumbar incisions. The mean incision length was 5.1 cm (range 0.25-50 cm). Fifty-nine percent of the wounds had previous areas of operative incisions. Complications included 1 poor cosmetic result and 4 cerebrospinal fluid (CSF) leaks. Of the 4 patients with CSF leaks, 2 required operative wound revision, and 1 required ventriculoperitoneal shunting for hydrocephalus. CONCLUSION: Cyanoacrylate skin adhesive is a viable means of obtaining cosmetic wound closure. Its use requires attention to proper skin approximation and hemostasis. In our experience, propensity for CSF leakage especially in reoperative procedures is a relative contraindication.

Malignant glial tumor arising from the site of a previous hamartoma/ganglioglioma: coincidence or malignant transformation?

Gangliogliomas are generally considered benign tumors. Although more commonly found in the brain, spinal cord ganglioglioma is a well established, albeit infrequent, entity. We describe a 2-decade clinical course of a patient initially diagnosed with a thoracolumbar 'glial-neuronal hamartoma' at age 4. Seventeen years after his first operation, local recurrence was noted. Despite subsequent multiple gross total resections and adjuvant therapy, histologic features became increasingly ominous and ultimately proved fatal. This is an unusual report and histologic presentation of a resected spinal cord ganglioglioma recurring as an anaplastic ependymoma/astrocytoma and subsequently a glioblastoma. It is quite likely that the originally resected ganglioglioma was actually part of a primitive neuroectodermal tumor which had undergone extensive maturation.

[New approaches to the surgical treatment of diffuse peritonitis]. / Neue Ansätze in der chirurgischen Therapie der diffusen Peritonitis.

OBJECTIVE: We intend to analyze if additional treatment concepts are necessary in any case as a part of the standard therapy next to the well established principle of source control in the treatment of secondary peritonitis. DESIGN: A treatment concept with early intervention, source control and extensive intraoperative lavage (20-301) should be evaluated as a standard procedure in a prospective survey. Additional treatment concepts will be applied only for special reason (on demand). RESULTS: From 11/1993 to 9/1997 241 patients with diffuse peritonitis were treated with the concept mentioned above. Additional treatment concepts as continuous postoperative lavage (n = 20) and staged lavage (n = 4) were applied as primary treatment in 24 patients only (10%), mainly for impossibility of source control and evisceration. Source control at the initial operation was possible in 216 patients (90%). Due to secondary evisceration 3 patients had to undergo laparostomy for staged lavage later. Severity of peritonitis was determined according to the Mannheim Peritonitis Index (median 26, range 15-43). The primary causes of peritonitis were perforation, leakage and abscess after operation (n = 56), followed by diverticular (n = 42) and gastric or duodenal perforation (n = 39). The hospital mortality rate was 14% in the whole group, and the postoperative morbidity rate was 39%. CONCLUSIONS: Due to progress in intensive care and antibiotic treatment only a few patients (ca. 10%) need additional therapies such as postoperative or staged lavage. Surgical source control in combination with intraoperative lavage is sufficient in most of the patients with diffuse peritonitis.

Observer reliability in histological grading of astrocytoma stereotactic biopsies.

This study provides an objective assessment of the reliability of histological grading of astrocytoma specimens obtained using stereotactic biopsy. Pathological diagnosis of brain tumors provides an index of disease severity and guides clinical practice in their treatment. It also functions as the gold standard in assessing the validity of diagnostic tests such as magnetic resonance imaging. Often diagnoses are made from biopsy material obtained using stereotactic technique. The current study was designed to evaluate this gold standard with regard to interobserver and intraobserver variability. Four certified neuropathologists from academic centers in the United States and Canada were asked to grade 30 brain biopsy specimens obtained stereotactically in patients with astrocytomas. Intraobserver agreement was analyzed in individual observers by comparing their first and second readings, separated by 5 to 14 weeks. Interobserver data were analyzed by comparing initial readings across all observers for individual diagnoses. Kappa analysis was used to measure agreement beyond chance. Intraobserver agreement was 74.73% for glioblastomas multiforme, 51.43% for anaplastic astrocytomas, and 65.22% for low-grade astrocytomas. The most common disagreements were between anaplastic astrocytomas and glioblastomas multiforme, followed by disagreements between anaplastic and low-grade astrocytomas. Interobserver agreement on initial readings was 62.41% (kappa 0.39) for glioblastomas, 36.04% (kappa 0.06) for anaplastic astrocytomas, and 57.14% (kappa 0.48) for low-grade astrocytomas. A significantly greater degree of reliability was seen in histopathological diagnoses of low- or high-grade astrocytomas than in those of intermediate-grade astrocytomas. Therefore, the highest variability occurs at the point of clinical decision making--namely, intermediate-grade tumors that may or may not be selected to receive adjuvant therapy. This considerable variability is an issue that needs to be recognized and further addressed by analysis of current and proposed astrocytoma grading schemes.