The mitochondrial protein frataxin is downregulated in hemodialysis patients

Background

The mitochondrial protein frataxin regulates iron metabolism for heme and iron sulfur cluster synthesis in the mitochondria and could be associated with the regulation of oxidative stress. To clarify the expression of frataxin and its association with uremia, we evaluated the mRNA and protein levels of frataxin in the polymorphonuclear leukocytes (PMNLs) of patients on hemodialysis (HD).

Methods

Uremic patients on HD (n = 18) and healthy control subjects (n = 18) were investigated. PMNLs were isolated by differential centrifugation. The mRNA levels of frataxin in isolated leukocytes were quantified by TaqMan real-time polymerase chain reaction. Frataxin protein expression in the cell lysate was evaluated using SDS-polyacrylamide gel electrophoresis and Western blotting.

Results

The frataxin/glyceraldehyde-3-phosphate dehydrogenase mRNA ratio in PMNLs from uremic patients was significantly lower than that in control subjects. Frataxin protein expression in uremic patients was also significantly lower than that in controls. Multiple regression analysis showed that frataxin mRNA levels were independently associated with the serum levels of both the oxidative stress marker malondialdehyde and the proinflammatory cytokine tumor necrosis factor-α.

Conclusion

The downregulation of frataxin seems to be linked with uremic status, which is usually associated with chronic inflammation and the acceleration of oxidative stress. Mitochondrial iron regulation may play a role in several comorbidities and in the poor prognosis in uremic patients. Further investigation is needed to elucidate whether reduced frataxin levels are linked to the pathological status of uremic patients and whether uremic substances affect frataxin expression.     

Totally laparoscopic complete resection of the remnant stomach for gastric cancer

Background

In patients having carcinoma in the remnant stomach, total resection of the remnant stomach with lymph node dissection is a prerequisite.

Materials and methods

We present the first series of successful totally laparoscopic complete gastrectomy (TLCG) for gastric remnant cancer.

Results

TLCG was successfully performed without adverse events during surgery in five patients with gastric remnant cancer. The median age of the patients was 72 years (range, 56-84 years), and there were three men and two women. Three of them had a Billroth I reconstruction and two had a Billroth II reconstruction, and in four cases following partial gastrectomy for gastric cancer and one for gastroduodenal ulcer. The median operative time was 360 min; blood loss was 20 ml. The median number of retrieved lymph nodes was 19. No complications occurred postoperatively, and all of the patients were discharged within the ninth postoperative day.

Conclusions

Although TLCG for gastric remnant cancer is a technically difficult and challenging operation that requires careful lysis of adhesion and dissection along the major vessels, as well as intracorporeal anastomosis, this procedure is technically feasible. Long-term follow-up is mandatory to validate oncological outcome.     

Pulmonary lobar root clamping and stapling technique: return of the “en masse lobectomy”

Purpose

Most thoracic surgeons have experienced difficulty dissecting the pulmonary hilus because of scarring. In such potentially dangerous situations, we advocate a method of clamping and severing the pulmonary lobar root structure en masse. The aim of this study was to evaluate en masse lobectomy, particularly considering the constellation of pulmonary vessels and the bronchus.

Methods

Twelve patients (median age 70 years) underwent en masse lobectomy. We retrospectively evaluated the surgical procedures and clinical outcomes. Care was taken to consider the remaining vessels and bronchus, which regulate the direction of device placement.

Results

Seven patients had inflammatory lung disease, four had primary pulmonary carcinoma, and one had suffered blunt chest trauma. Ten operations were elective and two were emergent. Lobectomy included the right upper lobe in two cases, the right middle lobe in three, the right lower lobe in two, the right middle-lower lobe in two, and the left lower lobe in three. A stapler was used in ten patients, and sutures were applied in three (both were used in one case). Morbidities included a pyothorax and a persistent air leak; both made a recovery. Mortality included one emergency case of acute respiratory distress syndrome. No bronchopleural or bronchovascular fistulas occurred.

Conclusions

We believe that the en masse lobectomy is an alternative and necessary technique in critical or unexpected situations, possibly as a last resort. Trauma and severe inflammation may be good indications for en masse lobectomy.     

Adult umbilical hernia with vertical dislocation

We present a case of adult umbilical hernia with vertical dislocation along the abdominal wall. The hernial sac arose from the internal ring and connected to the umbilicus 20?mm below the internal ring. The postoperative course was uneventful. Two years and four months after the operation there was no evidence of recurrent hernia even when abdominal pressure was increased, and the umbilicus looked acceptable. An umbilical hernia is usually within the umbilicus. The hernial sac arose from the internal ring so should be called an umbilical hernia not an epigastric hernia. It is unusual that the umbilical hernia dislocates vertically along the abdominal wall, while the umbilicus stays depressed. This atypical form of umbilical hernia has not been described previously as far as we know.     

Facial reanimation by transposition of the masseter muscle combined with tensor fascia lata,using the zygomatic arch as a pulley

We have created a new way of reanimating the face, involving transposition of the masseter muscle combined with tensor fascia lata, and using the zygomatic arch as a trochlea to reconstruct the inferior facial paralysis. We used it on five patients who had facial palsy after excision of malignant parotid tumours. The wide skin defect that exposed the masseter muscle after total parotidectomy was reconstructed with a free flap. This method differs from those of other methods of transposing the masseter muscle in that force is applied at an upper lateral angle. Our method provided dynamic raising of the upper lip, the corner of the mouth, and the nasolabial fold in four patients. We consider it to be useful, particularly for prompt surgical reconstruction of facial palsy after total parotidectomy with a wide defect in the skin of the cheek.     

Pyogenic discitis due to Abiotrophia adiacens

INTRODUCTIONAbiotrophia species have been referred to as nutritionally variant streptococci because of their fastidious nutritional requirements for growth. Abiotrophia species are difficult to identify with conventional solid culture.PRESENTATION OF CASEA 48-year-old woman was admitted to our hospital with severe low back pain and body temperature of 38.2 °C. Magnetic resonance imaging revealed edema and contrast enhancement of the L4 and L5 vertebral bodies with high signal intensity in the L3-4 and L4-5 intervertebral discs on the T2-weighted images. The patient underwent needle biopsy of the L3-4 disk. Cultures of disk biopsy samples and blood yielded gram positive cocci in short chains with scanty growth on chocolate agar. Further subculture with supplemented medium and subsequent 16S ribosomal RNA gene sequencing identified the pathogen as Abiotrhophia adiacens. The patient was treated with intravenous ampicillin. At 6-month follow-up, the patient was free of symptoms.DISCUSSIONCausative microorganisms remain unidentified in 25–40% of spinal infection cases. Abiotrophia species grow poorly on conventional solid media, and require pyridoxal or thiol group supplementation. Use of Brucella HK agar or GAM agar plate is helpful for detection of Abiotrophia species. We first confirmed the diagnosis by direct identification of Abiotrophia adiacens from infected disk. Abiotrophia species are one of the major pathogens of infective endocarditis accounting for 5% of cases. Considering their fastidious nature, it is likely that most cases of Abiotrophia discitis are falsely classified as culture-negative discitis; therefore, their role in pyogenic discitis may be underestimated.CONCLUSIONSubculture using nutritionally supplemented media is crucial for their identification.     

A novel gene required for natural competence in Aggregatibacter actinomycetemcomitans

Tanaka A, Fujise O, Chen C, Miura M, Hamachi T, Maeda K. A novel gene required for natural competence inAggregatibacter actinomycetemcomitans. J Periodont Res 2012; 47: 129–134. © 2011 John Wiley & Sons A/S Background and Objective: Natural competence is the ability of bacteria to take up extracellular DNA and incorporate it into their genomes. Some strains of Aggregatibacter actinomycetemcomitans, a critical periodontal pathogen, are naturally competent for transformation. However, information on natural competence genes is limited for this species. The aim of this study was to confirm the involvement of a novel gene identified near the fimbriae gene cluster in natural competence. Material and Methods: The functions of putative open reading frames (ORFs), designated AA00863–AA00865, in the Oralgen project database for A. actinomycetemcomitans strain HK1651, have not been determined. Using naturally transformable A. actinomycetemcomitans strains D7S‐1 and ATCC29523, we created deletion mutants of homologous genes of these ORFs. Natural competence in the study strains was determined using an agar‐based transformation frequency assay. Results: Mutation of the AA00865 homolog, which we named urpA in A. actinomycetemcomitans strain D7S‐1, resulted in the loss of natural competence, whereas mutations of the AA00864 and AA00863 homologs, located downstream of urpA gene, did not. Similar results were also observed in the mutants of A. actinomycetemcomitans ATCC29523. Complementation of the deleted sequence in the urpA mutant restored natural competence. Conclusion: The urpA gene is a novel gene required for natural competence in A. actinomycetemcomitans and does not exhibit significant homology with any natural competence genes previously identified in other bacterial species.