Intraosseous basivertebral nerve ablation for the treatment of chronic low back pain: a prospective randomized double-blind sham-controlled multi-center study.

PURPOSE: To evaluate the safety and efficacy of radiofrequency (RF) ablation of the basivertebral nerve (BVN) for the treatment of chronic low back pain (CLBP) in a Food and Drug Administration approved Investigational Device Exemption trial. The BVN has been shown to innervate endplate nociceptors which are thought to be a source of CLBP. METHODS: A total of 225 patients diagnosed with CLBP were randomized to either a sham (78 patients) or treatment (147 patients) intervention. The mean age within the study was 47 years (range 25-69) and the mean baseline ODI was 42. All patients had Type I or Type II Modic changes of the treated vertebral bodies. Patients were evaluated preoperatively, and at 2 weeks, 6 weeks and 3, 6 and 12 months postoperatively. The primary endpoint was the comparative change in ODI from baseline to 3 months. RESULTS: At 3 months, the average ODI in the treatment arm decreased 20.5 points, as compared to a 15.2 point decrease in the sham arm (p = 0.019, per-protocol population). A responder analysis based on ODI decrease ≥ 10 points showed that 75.6% of patients in the treatment arm as compared to 55.3% in the sham control arm exhibited a clinically meaningful improvement at 3 months. CONCLUSION: Patients treated with RF ablation of the BVN for CLBP exhibited significantly greater improvement in ODI at 3 months and a higher responder rate than sham treated controls. BVN ablation represents a potential minimally invasive treatment for the relief of chronic low back pain. These slides can be retrieved under Electronic Supplementary Material.

Improving telephone contact rates of patients discharged from the emergency department.

STUDY OBJECTIVE: This study investigated the rate of incorrect contact telephone numbers recorded during emergency department registration, and evaluated whether postdischarge contact rates can be improved by verifying the best contact number with the patient before discharge. METHODS: A prospective study was conducted with convenience sampling at a tertiary care hospital with an annual census of 60,000. Patients older than 18 years were enrolled, and the "unverified" telephone numbers recorded at registration were entered on the data sheet. Patients were then asked, "What number can we reach you at to discuss lab or x-ray results?" These "verified" numbers and additional demographic data were entered on the data sheet. Within 1 week, 3 calls were made to both the unverified and the verified numbers. Calls were considered successful if the patient, a friend, family member, or coworker was reached, or if the patient returned a message left on an answering machine. RESULTS: Four hundred eighteen patients (43% men) were enrolled; 72 (17%) patients provided a different best contact number than the one recorded on the chart. When unverified numbers were called, only 68.9% of patients were reachable, whereas when verified numbers were called, 81.8% of patients were contacted (P <.01). No statistical difference was found between patients who were successfully contacted and those who were not with regard to age, sex, race, or time of visit. Patients insured by health maintenance organizations were more likely to be reached (P =.02). CONCLUSION: Verification of a best contact telephone number significantly improves the ability to contact patients after ED discharge.

Vaginal evisceration.

Intestinal evisceration through the vagina is exceptionally rare. We report the cases of two patients presenting with this unusual clinical condition. Predisposing factors and management of vaginal evisceration are discussed.

Clonal deletion of some V beta+ T cells in peripheral lymphocytes from C57BL/6 mice infected with MHV3.

Mouse hepatitis virus type 3 infection is generally accompanied by a severe immune dysfunction involving thymic or splenic T cell subpopulations. We postulate that the peripheral lymphoid cell depletions were caused by a selective deletion of some V beta subsets of mature T cells, as observed with superantigens. We have examined the expression of V beta 6, V beta 8 and V beta 14 in T cell subpopulations from the spleen and lymph nodes of pathogenic L2-MHV3-infected C57BL/6 mice. Cytofluorometric study showed decreases in splenic V beta 8+, V beta 6+, and V beta 14+ T cell subpopulations at 72 hrs post-infection. Single positive CD4+ T cells were diminushed but not the CD8+ cells. In contrast, the various V beta splenic cell populations were not modified in mice infected with a non- pathogenic YAC-MHV3 variant. However, the V beta 8/CD4 ratio increased in splenic cells but decreased in lymphocytes from lymph nodes. The V beta 14/CD4 ratio decreased only in splenic cells while V beta 6/CD4 ratios were not modified. These results suggest that alterations in V beta cell populations may play a role in the L2-MHV3-induced immunodeficiency.

Nonconvulsive status epilepticus.

A 49-year-old man presented with dizziness and altered behavior associated with a nonconvulsive seizure. He had a long history of well-controlled tonic-clonic seizures and daily episodes of 10-second staring spells. Despite normal neurological and laboratory examinations, an emergent electroencephalogram showed changes consistent with nonconvulsive generalized status epilepticus.

Incidence of aspiration after urgent intubation.

This study sought to determine the incidence of aspiration after urgent endotracheal intubation (ET) performed in the emergency department (ED), and to offer a descriptive evaluation of these intubations. In a retrospective review of 133 charts, 87 patients met inclusion criteria. Aspiration occurred in 3 (3.5%) patients (95% confidence interval, 0%, 7.4%). One had witnessed aspiration, and 2 had positive sputum cultures. None of the 87 patients had a positive chest radiograph or unexplained hypoxemia up to 48 hours after ET. Rapid-sequence induction and oral ET was performed in 79 (91%) patients, whereas 4 spontaneously breathing patients were nasally intubated. Seventy percent of patients underwent ET by PGY I or II residents, 29% by PGY III or IV residents, and 1% by ED attending physicians. Seventy-seven patients were intubated on the first attempt, and airway blood or vomitus during ET was noted in 11 patients. This study offers significant descriptive information regarding urgent ET performed in the ED, and shows that aspiration after urgent ET occurs infrequently in ED patients.

[Cloning, expression and characterization of HIV-1 gp60 partially or completely deleted in the V3 loop]. / Clonage, expression et caractérisation de gp160 du VIH-1, portant des délétions partielles ou totales dans la boucle V3.

In order to better understand the role of the immunodominant V3 loop in the type-specific immune response and also to determine if this sequence has a role in AIDS pathogenesis, notably in the induction of apoptosis in CD4+ cells, we have introduced 2 modifications in the env gene from pNL4-3: a partial deletion in the V3 loop, keeping only the conserved tip of the loop GPGRAF consensus sequence (env delta V3-GPGRAF) and, secondly, a complete deletion of V3 sequence plus 43 nucleotides in C3 (env delta V3+). These constructions as well as the non-modified env gene, were cloned and expressed in a baculovirus system. Western blot analysis has shown that both modified env gene products reacted with a reference anti-HIV-1 serum to the same extent as the non-modified gp 160. However, in contrast to the non-modified env-protein and to env delta V3-GPGRAF, the env delta V3+ protein failed to bind to CD4 molecule, although V3 is not directly involved in receptor binding. These modified and non-modified recombinant proteins will be very useful to determine the potential of the partially or totally V3-deleted gp 160 to induce broadly reactive neutralizing antibodies and also to determine if V3 has a role in certain aspects of HIV-induced pathogenesis, notably apoptosis.

Evaluation of auditory enhancement and auditory suppression in listeners with normal hearing and reduced speech recognition in noise.

A number of individuals complain of difficulties with speech recognition in noise in spite of normal hearing. This has prompted a search for disruptions in other areas of auditory processing that may account for these deficits. Two processes that may be related to speech recognition, auditory suppression and auditory enhancement, were evaluated in five listeners with normal speech recognition in noise (NSRN) and five listeners with reduced speech recognition in noise (RSRN). Although differences between the two groups were not observed for enhanced forward masking, significant differences were observed in two-tone suppression when the duration of the suppressor was varied. Those with RSRN showed greater suppression than those with NSRN when the suppressor onset preceded the masker onset.

Long-term lumboureteral shunt removed secondary to iatrogenic meningitis.

With the advent of ventriculoperitoneal cerebrospinal fluid shunts for communicating hydrocephalus, rarely does the physician see patients with alternate types of shunting devices. The once popularized lumboureteral shunt is unique for its potential complications of dehydration, electrolyte imbalances, infection, and the sacrifice of a functioning kidney. This article presents the case of a woman with a longstanding lumboureteral shunt that was removed after the onset of iatrogenic meningitis secondary to an ascending urinary tract infection.

Analysis of long-term viral expression in CEM cells persistently infected with non syncytium-inducing HIV-1 strains.

CEM cells were infected with three HIV-1 non syncytium-inducing (NSI) strains obtained from AIDS patients or seropositive individuals. The surviving cells were followed for several months in the persistently infected cultures designated 65870/CEM, 65871/CEM and 3929/CEM, and analyzed for virus expression using light and electron microscopy, immunofluorescence, reverse transcriptase assay, polymerase chain reaction amplification (PCR), nucleic acid hybridization and flow cytometry. The virus isolates induced relatively few syncytia and other cytopathic effects in the corresponding cell lines and the number of cells positive for virus expression never rose above 44%. Distinct peaks of antigen-positive cells were obtained, coincident with high levels of reverse transcriptase activity. The cultures were strongly resistant to superinfection by laboratory strain Lai, with the exception of 65870/CEM which expressed HIV antigens in up to 15% of the cells for a few days. However, cell lysis was minimal in all cases. After long-term cultivation of the three cultures, no antigen-positive cells were detected and no trace of virus expression could be observed. The remaining cells consisted entirely of CD4-negative cells. PCR analyses indicated that cells harboring a provirus were progressively eliminated from the cultures, leaving only virus-free cells. In this system, cells carrying a latent provirus survive for a limited period of time before virus activation induces cell lysis. These results suggest that at least three types of cells exist in the CEM cell line: CD4-positive cells which are rapidly killed by the virus, a second type harboring a latent viral genome after the infection and which grow normally until activation of the resident genome by external or internal signal(s), and a third type which represents rare CD4-negative cells present in the initial CEM population and which are selected for by the NSI isolates. This is the first study documenting specific interactions between NSI strains of HIV-1 and distinct subpopulations of CEM cells grown as a single cell culture.

Exploration of factors beyond audibility that may influence speech recognition.

The effects of reduced ability to differentiate acoustic information on speech reception are difficult to separate from the effects of reduced absolute sensitivity. One possible way is to explore abilities to differentiate acoustic information while holding absolute sensitivity constant. Two auditory phenomena known as enhancement and suppression, which are thought to be related to speech reception ability, were evaluated in persons with normal absolute sensitivity who had either normal or reduced speech recognition in noise. Results of forward masking experiments do not support the notion that enhancement or suppression is reduced in persons with reduced speech recognition in noise. However, their pattern of performance differed from that of listeners with normal speech recognition in noise when the duration of certain complex maskers was varied.

Consistency of electroacoustic characteristics across components of FM systems.

In the absence of national or international electroacoustic standards for the evaluation of Frequency Modulated (FM) amplification systems, it becomes important to know the variability one may expect across similar models. Evaluation of thirty FM systems of the same model obtained from three different educational sites was performed to determine the variability that may occur as a result of the receiver, lapel microphone, or neckloop. There was a range as great as 20 dB in high frequency average saturation sound pressure level and equivalent input noise across receivers, lapel microphones, and neckloops. These results highlight the need for regular electroacoustic monitoring of not only the FM transmitter and receiver, but also the individual components, such as the lapel microphone and the neckloop.

Performance of hearing-impaired persons on auditory enhancement tasks.

An auditory enhancement effect was evaluated in normal and hearing-impaired persons using a paradigm similar to that used by Viemeister and Bacon [J. Acoust. Soc. Am. 71, 1502-1507 (1982)]. Thresholds for a 2000-Hz probe were obtained in two forward-masking conditions: (1) the standard condition in which the masker was a four-component harmonic complex including 2000 Hz, and (2) the enhancing condition in which the same harmonic complex except for the exclusion of the 2000-Hz component preceded the four-component masker. In addition, enhancement for speech was evaluated by asking subjects to identify flat-spectrum harmonic complexes that were preceded by inverse vowel spectra. Finally, suppression effects were evaluated by measuring forward-masked thresholds for a 2000-Hz probe as a function of suppressor frequency added to a 2000-Hz masker. Across all subjects, there was evidence of enhancement and better vowel recognition in those persons who also demonstrated evidence of suppression; however, two of the normal-hearing persons demonstrated reduced enhancement yet normal suppression effects.

Insert earphones for speech recognition testing.

Performance-intensity functions for PB word lists were run on 19 normal-hearing subjects and 15 subjects with sensorineural hearing losses. Comparisons were made between standard supra-aural earphones (TDH-49P) and insert phones (ER-3A). Results showed that, at least for the higher sensation levels where word recognition tests are usually performed, the phones may be used interchangeably. Using insert earphones for word recognition tests can have several beneficial effects with respect to cross hearing and masking.

[Oral and parenteral immunization with HIV immunosome induce the secretion of IgA specific of HIV-1 in the salivary and the production of circulatory IgA in mice and rabbits]. / Une immunisation orale et parentérale avec l'immunosome-VIH induit une sécrétion d'IgA spécifique du VIH-1 dans la salive et la production d'IgA circulants chez la souris et le lapin.

Given the sexual transmission of HIV, the establishment of a genital mucosal immunity through secretory IgA may be necessary to achieve protection. We have investigated if repeated stimulations of oral mucosa with HIV-Immunosomes would lead to the production of secretory IgA in saliva and also, if such an oral immunization could prime the immune system to an early systemic immune response following a parenteral immunisation with a low dose of the antigen. HIV-1 gp 160-specific secretory IgA were detected in the saliva of all rabbits orally immunized with HIV-Immunosomes. As early as one week after the parenteral immunization, high titers of serum IgA, IgM and IgG were detected both in mice and rabbits that had been orally stimulated with the antigen. These antibodies could neutralize HIV infectivity in vitro. Animals that were immunized only parenterally showed a very weak humoral immune response.

Use of electrophysiologic tests to measure disease progression in ALS therapeutic trials.

A battery of electrophysiologic tests was developed to assess the relative degree of lower and upper motor neuron (spasticity) deficit in a group of ALS patients enrolled in a therapeutic trial. Test results were correlated with strength in the tibialis anterior muscle as determined by measurement of maximum voluntary isometric contraction (MVIC), using strain gauge tensiometers, and were also correlated with a clinical spasticity rating scale. Patients were tested every 6 to 8 weeks over more than 1 year. Compound muscle action potential amplitude (CMAPa) from tibialis anterior correlated best with MVIC and also showed a strong linear correlation with time, as did MVIC. Other tests correlated poorly with MVIC on the average, although individual patients did show high correlations. In those patients where correlation between CMAPa and MVIC was low, MVIC did not show a high linear correlation with time and was also highly variable. This study suggests that the addition of CMAPa should be considered in ALS therapeutic trials if MVIC is not available. In addition, CMAPa can be useful in study samples where MVIC deterioration is not linear over time or is highly variable.

5-azacytidine and 5-azadeoxycytidine inhibit human immunodeficiency virus type 1 replication in vitro.

Chemotherapeutic agents which affect the integration, stability, or inducibility of the human immunodeficiency virus (HIV) provirus would have considerable value in treating acquired immunodeficiency syndrome. Two nucleoside analogs of cytosine, 5-azacytidine and 5-azadeoxycytidine, which seem to have such value because of their capabilities to affect both the stability and the methylation patterns of the nucleic acids into which they are incorporated, were tested for their ability to inhibit the replication of HIV type 1 (HIV-1) in human CEM T cells in vitro. 5-Azadeoxycytidine (1 microM) completely inhibited HIV replication in CEM cells, by the criteria of reduced viral antigen expression and decreased supernatant reverse transcriptase activity, with little toxicity for the treated cells. 5-azacytidine (1 microM) also inhibited HIV replication, but less effectively. When added 2 or more h after CEM cells were infected with HIV-1, both 5-azacytosine derivatives were less effective than they were when added at the time of infection. Even 2 h of exposure to 5-azadeoxycytidine was sufficient for inhibition of HIV replication. Although long exposure to either analog at concentrations of 1 microM would result in pronounced cellular cytotoxicity, the the fact that short exposures to the same dose of drug inhibit HIV replication but are not toxic for the cells implies that cellular toxicity itself is not an important mechanism of the antiviral action of the analogs.