The microstructure and micromechanics of the tendon-bone insertion

The exceptional mechanical properties of the load-bearing connection of tendon to bone rely on an intricate interplay of its biomolecular composition, microstructure and micromechanics. Here we identify that the Achilles tendon-bone insertion is characterized by an interface region of ∼500 μm with a distinct fibre organization and biomolecular composition. Within this region, we identify a heterogeneous mechanical response by micromechanical testing coupled with multiscale confocal microscopy. This leads to localized strains that can be larger than the remotely applied strain. The subset of fibres that sustain the majority of loading in the interface area changes with the angle of force application. Proteomic analysis detects enrichment of 22 proteins in the interfacial region that are predominantly involved in cartilage and skeletal development as well as proteoglycan metabolism. The presented mechanisms mark a guideline for further biomimetic strategies to rationally design hard-soft interfaces.

[Vocational rehabilitation after total laryngectomy]

BACKGROUND

Aim of this study was to find out how many patients after a total laryngectomy (TLE) return to work successfully and what factors support vocational rehabilitation.

PATIENTS AND METHODS

Laryngectomees (n=231) aged up to 60 years completed questionnaires and structured interviews before TLE (t1), before rehabilitation (t2), at the end of rehabilitation (t3), 1 year after TLE (t4), 2 years after TLE (t5), and 3 years after TLE (t6).

RESULTS

Prior to TLE, 38% of all respondents were employed, 34% were unemployed, 23% received disability-related and 3% age-related pension retirement. One year after TLE, 13% were employed, 15% 2 years and 14% 3 years after TLE. Unemployed were 10% (t4), 5% (t5), and 7% (t6) of the patients. For 59% of all respondents it was very important to have a job. Predictors of successful vocational rehabilitation were employment prior to TLE, age <50 years, being self-employed or clerical employee, good physical functioning, good speech intelligibility, high motivation to go back to work, and support from colleagues.

CONCLUSION

Only few laryngectomees return to work. However, even before TLE only a third of the patients was employed, another third was unemployed. Most of the patients receive pension retirement after TLE. As return to work is important for many patients, patient consultations should consider possibilities to support vocational rehabilitation before offering to apply for retirement.

[The role of sex in voice restoration and emotional functioning after laryngectomy]

BACKGROUND

Data on psychosocial factors of laryngectomized women is rare. All means of alaryngeal voice production sound male due to low fundamental frequency and roughness, which makes postlaryngectomy voice rehabilitation especially challenging to women. Aim of this study was to investigate whether women use alaryngeal speech more seldomly and therefore are more emotionally distressed.

MATERIAL AND METHODS

In a cross-sectional multi-centred study 12 female and 138 male laryngectomees were interviewed. To identify risc factors on seldom use of alaryngeal speech and emotional functioning, logistic regression was used and odds ratios were adjusted to age, time since laryngectomy, physical functioning, social activity and feelings of stigmatization.

RESULTS

Esophageal speech was used by 83% of the female and 57% of the male patients, prosthetic speech was used by 17% of the female and 20% of the male patients and electrolaryngeal speech was used by 17% of the female and 29% of the male patients. There was a higher risk for laryngectomees to be more emotionally distressed when feeling physically bad (OR=2,48; p=0,02) or having feelings of stigmatization (OR=3,94; p≤0,00). Besides more women tended to be socially active than men (83% vs. 54%; p=0,05).

CONCLUSIONS

There was no influence of sex neither on use of alaryngeal speech nor on emotional functioning. Since there is evidence for a different psychosocial adjustment in laryngectomized men and women, more investigation including bigger sample sizes will be needed on this special issue.

Münchhausen-Syndrom und chronische Otitis media

In this case report an artificial disorder with symptoms of chronic otitis media and progressive hearing loss is described. This represents a rare case of Munchausen syndrome. The difficulties in diagnosis and therapy are shown by the development of the disease, produced by self damaging activities.

Urolithiasis update: clinical experience with the Swiss LithoClast

This article describes the authors' first experience using the EMS Swiss LithoClast pneumatic lithotriptor in the management of middle and distal ureteral calculi. Also presented is a review of the literature comparing different modalities of intracorporeal lithotripsy. A retrospective analysis was performed on 11 patients treated with the Swiss LithoClast using the Circon ACMI MR6 Rigid Mini-ureteroscope (7 patients with distal calculi and 4 patients with midureteral calculi). The lithotriptor successfully fragmented 91% of the calculi, independent of stone composition. Complete failure of fragmentation was only encountered in one patient, and this was secondary to the lithotriptor's inherent ballistic force causing retrograde passage of the calculus. One patient had postoperative radiographic evidence of stone fragments along the ureteral stent. There was no intraoperative morbidity or long-term complications encountered with use of the pneumatic lithotriptor. Additionally, patients' overall satisfaction was 91% with respect to the procedure itself and relief of preoperative pain. The only significant postoperative complaint was ureteral stent discomfort in one patient. The authors conclude that the EMS Swiss LithoClast pneumatic lithotriptor is a safe and effective tool in the management of middle and distal ureteral calculi. However, as noted with one patient, there is always a risk of stone push from the ballistic force of the lithotriptor.

Quantitation of human immunodeficiency virus type 1 RNA in different biological compartments

Little information is available describing viral loads in body fluids other than blood. In addition, the suitability of commercially available assays for human immunodeficiency virus type 1 (HIV-1) RNA quantitation has not been evaluated in most nonblood fluids. We compared Organon Teknika's nucleic acid sequence-based amplification method (NASBA) and Roche's Amplicor HIV-1 Monitor (reverse transcriptase PCR [RT-PCR]) for quantitating HIV-1 RNA in cerebrospinal fluid (CSF), saliva, breast milk, seminal plasma, and cervical-vaginal lavage fluid (CVL). Saliva and breast milk frequently demonstrated some inhibition in the RT-PCR assay, similar to the inhibition previously described in seminal plasma. Inhibition of the RT-PCR assay was not observed with CSF or CVL, nor in any of the NASBA assays. When fluids from HIV-infected individuals were tested by RT-PCR and NASBA, 73 and 27% of CSF samples and 60 and 40% of breast milk specimens had detectable RNA, respectively. These differences were not statistically significant. In cross-sectional studies using RT-PCR to measure viral RNA in paired blood plasma and CSF samples, 71% of blood plasma samples and 42% of CSF samples were positive. A similar analysis using NASBA with paired blood plasma and CVL, saliva, or seminal plasma samples revealed 91% were blood plasma positive and 55% were CVL positive, 76% were blood plasma positive and 46% were saliva positive, and 83% were blood plasma positive and 63% were seminal plasma positive. NASBA worked fairly well to quantitate HIV-1 RNA from all fluids without apparent inhibition. RT-PCR performed well on CVL and CSF, frequently with greater sensitivity, although its use in other fluids appears limited due to the presence of inhibitors. These studies demonstrate that viral loads in nonblood fluids were generally lower than in blood.

Potent antiretroviral treatment of HIV-infection results in suppression of the seminal shedding of HIV. The Swiss HIV Cohort Study

OBJECTIVE

The amount of HIV in semen likely influences infectiousness. Antiretroviral therapy decreases HIV-RNA in semen, but data on HIV concentrations in semen in a large cohort of men with suppressed HIV-RNA in blood is unavailable.

METHODS

Male patients with a treatment-induced reduction of HIV-RNA load in plasma below 400 copies/ml were asked to donate a semen and blood sample. Blood and seminal plasma were tested for the presence of HIV-RNA by the NucliSens method (detection limit 400 copies/ml). Seminal cell samples from 67 patients were further analysed for the presence of HIV-DNA using a nested DNA-polymerase chain reaction. Results of RNA and DNA testing in semen were compared with 55 HIV-positive antiretroviral therapy-naive men.

RESULTS

A total of 114 patients participated in the study. Seminal plasma HIV-RNA was detectable in only two patients [1.8%, 95% confidence ratio (CI), 0-4.2%] compared with a detection frequency of 67% in untreated controls [Odds ratio (OR), 0.01; 95% CI, 0-0.03]. Detection of cell-associated HIV-DNA in semen was significantly less frequent (16 versus 38%) in patients receiving suppressive therapy compared with untreated controls (OR, 0.32; 95% CI, 0.12-0.80).

CONCLUSION

In patients with treatment-induced suppression of blood viral load the likelihood of having detectable HIV in semen is very low (< 4%). In addition, seminal shedding of cell-free and cell-associated HIV is significantly lower than in an untreated population of HIV-infected asymptomatic men. On a population basis, this effect of therapy may help to reduce sexual transmission of HIV. However, individual patients may still be infected as evidenced by continued shedding of cells harbouring the HIV provirus.

Characterization of V3 sequence heterogeneity in subtype C human immunodeficiency virus type 1 isolates from Malawi: underrepresentation of X4 variants

We have examined the nature of V3 sequence variability among subtype C human immunodeficiency virus type 1 (HIV-1) sequences from plasma-derived viral RNA present in infected men from Malawi. Sequence variability was assessed by direct sequence analysis of the V3 reverse transcription-PCR products, examination of virus populations by a subtype C V3-specific heteroduplex tracking assay (V3-HTA), and selected sequence analysis of molecular clones derived from the PCR products. Sequence variability in V3 among the subtype C viruses was not associated with the presence of basic amino acid substitutions. This observation is in contrast to that for subtype B HIV-1, where sequence variability is associated with such substitutions, and these substitutions are determinants of altered coreceptor usage. Evolutionary variants in subtype C V3 sequences, as defined by the V3-HTA, were not correlated with the CD4 level in the infected person, while such a correlation was found with subtype B V3 sequences. Viruses were isolated from a subset of the subjects; all isolates used CCR5 and not CXCR4 as a coreceptor, and none was able to grow in MT-2 cells, a hallmark of the syncytium-inducing phenotype that is correlated with CXCR4 usage. The overall sequence variability of the subtype C V3 region was no greater than that of the conserved regions of gp120. This limited sequence variability was also a feature of subtype B V3 sequences that do not carry the basic amino acid substitutions associated with altered coreceptor usage. Our results indicate that altered coreceptor usage is rare in subtype C HIV-1 isolates in sub-Saharan Africa and that sequence variability is not a feature of the V3 region of env in the absence of altered coreceptor usage.

Perforation of acquired small bowel diverticulum

A 77-year old woman was seen with an unusual pathologic entity after emergent abdominal exploration--a ruptured small bowel diverticulum. This patient had a known previous history of colonic diverticulosis when she had acute onset of severe abdominal pain. The patient underwent an exploratory laparotomy with resection of representative segments of small and large bowel. The large bowel had evidence of diverticulosis, while the small bowel resected segment had evidence of diverticulitis with rupture. An extensive review of the literature revealed a very small number of reported cases in the world literature (less than 150 cases). We reviewed the history of reported cases of ruptured and nonruptured small bowel diverticular disease, as well as this case.

Comparison of NucliSens and Roche Monitor assays for quantitation of levels of human immunodeficiency virus type 1 RNA in plasma

We compared the performance of Organon Teknika's NucliSens and Roche Diagnostic Systems' Monitor quantitative human immunodeficiency type 1 RNA assays. Both had similar linearity and sensitivity over most of the dynamic range of the assays, although the Monitor assay was superior at the low range of RNA values while the NucliSens assay was more consistent at higher RNA values. NucliSens generally showed less interassay variability.

Quantitation of human immunodeficiency virus type 1 RNA in plasma by using blood dried on filter paper

We compared whole blood dried on filter paper to the standard assay with frozen cell-free plasma for use in the quantitation of the human immunodeficiency virus RNA load in blood. RNA values from filter paper, corrected for the hematocrit, gave results comparable to those of the standard assay in terms of sensitivity and reproducibility.

Quantitative culture of HIV-1 from bronchoalveolar lavage cells

Determination of the infectious virus burden at the organ level is critical for understanding the pathophysiology of human immunodeficiency virus type 1 (HIV-1) infection. To evaluate the burden of HIV-1 in the lung, quantitative cultures were performed on bronchoalveolar lavage (BAL) cells from 11 HIV-1 seropositive subjects without respiratory infections and compared with peripheral blood mononuclear cells (PBMC) obtained from the same subjects. Fifty percent (50%) of subjects had positive BAL cell cultures while 82% had positive PBMC cultures. There was much less virus cultured from BAL cells than from PBMCs, whether using phytohemagglutinin (PHA)-stimulated peripheral blood lymphocyte (PBL) targets (p < 0.05) or adherent monocyte targets (p < 0.02). There was no significant difference between the HIV-1 titers obtained for BAL cells whether using PHA-stimulated PBL or adherent monocyte targets (p = 0.13). These studies demonstrate that BAL cell cultures for HIV-1 in subjects without respiratory infections are less frequently positive than PBMC cultures, that less virus can be recovered from BAL cells than from PBMC, and that HIV-1 isolates from BAL cells replicate in both PHA-stimulated PBL targets and adherent monocyte targets. Quantitative assessment of virus burden in the lung is important for future studies of HIV-1 pathogenesis and for evaluating potential antiretroviral therapies aimed at altering the natural history of organ dysfunction associated with retroviral replication.