Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation

Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by gradient centrifugation for use in assisted reproductive procedures. Efficacy was assessed in terms of percentages of sperm recovery, sperm vitality and motility, normal sperm morphology and normal sperm chromatin condensation. No significant difference was found in the recovery of spermatozoa for men with both normal sperm counts and oligozoospermia, between PVP-coated and silane-coated particle solutions. Iodixanol had significantly lower sperm recovery compared to the other products. Sperm vitality, progressive motility, normal morphology and normal chromatin condensation did not differ significantly between any of the sperm isolation products.      

The meaning of pain influences its experienced intensity

This experiment tested whether meaning influences the experience of pain. Thirty-one healthy students participated in a study on evaluations of various stimuli placed against the neck. By suggesting that a very cold metal bar was either hot or cold, the potentially tissue-damaging property of the stimulus was experimentally manipulated. A manipulation check revealed that participants believed the experimenter's information, as they rated the bar as more hot in the corresponding condition than in the other condition. Confirming the hypothesis that tissue-damaging meaning influences the experience of pain, participants who were told that the bar was hot rated it as more painful than participants who were told that it was cold. Damage interpretations mediated the effect of information on pain intensity scores, which supported the theory that tissue-damage is a crucial aspect of meaning to influence the subjective intensity of pain.     

Caffeine-mediated effects on reproductive health over two generations in rats

The present study was designed to investigate the mechanism(s) underlying previously observed birth weight differences found in the first litter of the second (F₂) generation bred from caffeine-exposed F₁ females. The effect of exposure to caffeine in utero on subsequent sexual receptivity, fertility, gestation length, parturition, nesting activity, maternal behaviour, and reproductive senescence in the F₁ mothers, and the viability of the F₂ offspring was investigated. This information was collected by breeding control or caffeine exposed females for 8 consecutive litters. It was demonstrated that exposure to caffeine did not affect the sexual receptivity, fertility, gestation length, or maternal behaviour of the F₁ females, but parturition was prolonged and the viability of the F₂ generation was seriously jeopardised. Many F₂ pups were born significantly larger than their control counterparts and a significant proportion of litters (after the first two litters) were wholly stillborn. It was concluded that a changed genetic program, mediated via the F₂ fetus, delayed the normal progression of parturition. This, in turn, compromised the F₁ mothers and caused increased mortality of their offspring. The severity of the outcome was dose dependent.     

Development and validation of a questionnaire assessing the perceived control in health care among older adults with care needs in the Netherlands

Purpose

In response to the increased emphasis placed on older people’s self-reliance in many welfare societies, we aimed to develop and validate a measurement instrument, assessing perceived control in health care among older adults with care needs. The target group consists of older people who live (semi-)independently and use professional health care, with or without informal care.

Methods

Phase I (development) of the study consisted of the construction of the instrument based on the input from a variety of stakeholders. Phase II (validation) entailed a quantitative study in a sample of 247 respondents selected from the Longitudinal Aging Study Amsterdam, to assess the instrument’s construct validity (structural validity and hypotheses testing) and reliability (internal consistency).

Results

The questionnaire consists of 29 items, related to organizing professional care, communication with care professionals, health management in the home situation, planning (more) complex care in the future, and perceived support from the social network. Based on a factor analysis, we identified three subscales: (I.) ‘perceived personal control in health care’; (II.) ‘anticipated personal control regarding future health care’; and (III.) ‘perceived support from the social network,’ with internal consistencies varying from Cronbach’s α = .71 to .90. Factor I was associated with mastery, self-efficacy, self-esteem (r = .31–.35) and factor III with social loneliness (r = ?.42). Factor II correlated less strongly with mastery, self-efficacy, and self-esteem (r < .30).

Conclusion

Our questionnaire revealed sufficient construct validity and internal consistency. The instrument provides a basis for further quantitative research regarding control, especially in relation to health care-related outcomes.

     

FcγR interaction is not required for effective anti-PD-L1 immunotherapy but can add additional benefit depending on the tumor model

Immunomodulatory antibodies blocking interactions of coinhibitory receptors to their ligands such as CTLA-4, PD1 and PD-L1 on immune cells have shown impressive therapeutic efficacy in clinical studies. The therapeutic effect of these antibodies is mainly mediated by reactivating antitumor T cell immune responses. Detailed analysis of anti-CTLA4 antibody therapy revealed that an optimal therapeutic efficacy also requires binding to Fc receptors for IgG, FcγR, mediating depletion of intratumoral regulatory T cells. Here, we investigated the role of Fc binding in anti-PD-L1 antibody therapy in the MC38 C57BL/6 and CT26 BALB/c colon adenocarcinoma tumor models. In the MC38 tumor model, all IgG subclasses anti-PD-L1 showed similar therapeutic efficacy when compared to each other in either wild-type mice or in mice deficient for all FcγR. In contrast, in the CT26 tumor model, anti-PD-L1 mIgG2a, the IgG subclass with the highest affinity for activating FcγR, showed stronger therapeutic efficacy than other IgG subclasses. This was associated with a reduction of a myeloid cell subset with high expression of PD-L1 in the tumor microenvironment. This subclass preference for mIgG2a was lost in C57BL/6 × BALB/c F1 mice, indicating that the genetic background of the host may determine the additional clinical benefit of the high affinity antibody subclasses. Based on these data, we conclude that FcγR are not crucial for anti-PD-L1 antibody therapy but might play a role in some tumor models.     

Number of sputum specimens during treatment follow-up of tuberculosis patients: two or one?

Setting:

National Institute for Research in Tuberculosis clinics in Chennai and Madurai, India.

Objective:

To examine the pattern of serial smears (negative-negative [NN], negative-positive [NP], positive-negative [PN], positive-positive [PP]) during treatment follow-up of culture-confirmed new smear-positive tuberculosis (TB) patients, and the proportion of culture-negatives in each category.

Design:

We reviewed the records and extracted follow-up smear (fluorescent microscopy) and culture (Löwenstein-Jensen) results of patients enrolled in clinical trials from January 2000 to August 2012 and treated with the Category I regimen (2EHRZ₃/4HR₃). Data entry and analysis were performed using EpiData.

Results:

Among 520 patients (176 infected with the human immunodeficiency virus), the proportions of culture-negative patients with NN, discordant (PN or NP) and PP patterns were approximately 98%, 80% and 40%, respectively. The smear-positive culture-negative phenomenon was more frequent in follow-up smear results graded 1+, followed by 2+ and 3+.

Conclusion:

There is justification for discontinuing the examination of second specimens during treatment follow-up among TB patients. However, a positive result on the first smear needs to be confirmed by a second positive result before making clinical management decisions. The World Health Organization may need to reconsider its recommendation on this issue.     

Assessment of the implementation of the primary health care package at selected sites in South Africa

A major objective of public health policy in South Africa is to develop a district-based health service focused on the delivery of primary health care. The primary health care package has been developed to promote the delivery of a number of services at the primary level. This paper assesses the implementation of the package in eight historically disadvantaged urban renewal nodes singled out for accelerated development through the government's urban renewal strategy. Data were gathered by way of interviews with primary health care facility managers and programme co-ordinators and through physical observations at facilities. The findings show that while some facilities were able to offer clients most of the services specified by the package, many others were unable do so. The urban renewal nodes differed noticeably in this respect.     

Definition of gross tumor volume in lung cancer: inter-observer variability.

BACKGROUND AND PURPOSE: To determine the inter-observer variation in gross tumor volume (GTV) definition in lung cancer, and its clinical relevance. MATERIALS AND METHODS: Five clinicians involved in lung cancer were asked to define GTV on the planning CT scan of eight patients. Resulting GTVs were compared on the base of geometric volume, dimensions and extensions. Judgement of invasion of lymph node (LN) regions was evaluated using the ATS/LCSG classification of LN. Clinical relevance of the variation was studied through 3D-dosimetry of standard conformal plans: volume of critical organs (heart, lungs, esophagus, spinal cord) irradiated at toxic doses, 95% isodose volumes of GTVs, normal tissue complication probabilities (NTCP) and tumor control probabilities (TCP) were compared for evaluation of observer variability. RESULTS: Before evaluation of observer variability, critical review of planning CT scan led to up- (two cases) and downstaging (one case) of patients as compared to the respective diagnostic scans. The defined GTVs showed an inter-observer variation with a ratio up to more than 7 between maximum and minimum geometric content. The dimensions of the primary tumor had inter-observer ranges of 4.2 (transversal), 7.9 (cranio-caudal) and 5.4 (antero-posterior) cm. Extreme extensions of the GTVs (left, right, cranial, caudal, anterior and posterior) varied with ranges of 2.8-7.3 cm due to inter-observer variation. After common review, only 63% of involved lymph node regions were delineated by the clinicians (i.e. 37% are false negative). Twenty-two percent of drawn in lymph node regions were accepted to be false positive after review. In the conformal plans, inter-observer ranges of irradiated normal tissue volume were on average 12%, with a maximum of 66%. The probability (in the population of all conformal plans) of irradiating at least 95% of the GTV with at least 95% of the nominal treatment dose decreased from 96 to 88% when swapping the matched GTV with an unmatched one. The average (over all patients) inter-observer range in NTCP varied from 5% (spinal cord) to 20% (ipsilateral lung), whereas the maximal ranges amounted 16% (spinal cord) to 45% (heart). The average TCP amounted 51% with an average range of 2% (maximally 5%) in case of matched GTVs. These values shifted to 42% (average TCP) with an average range of 14% (maximally 31%) when defining unmatched GTVs. Four groups of causes are suggested for the large inter-observer variation: (1) problems of methodology; (2) impossible differentiation between pathologic structures and tumor; or (3) between normal structures and tumor, and (4); lack of knowledge. Only the minority of these can be resolved objectively. For most of the causal factors agreements have to be made between clinicians, intra- and inter-departmentally. Some of the factors will never be unequivocally solved. CONCLUSIONS: GTV definition in lung cancer is one of the cornerstones in quality assurance of radiotherapy. The large inter-observer variation in GTV definition jeopardizes comparison between clinicians, institutes and treatments.     

Factors affecting treatment outcomes in drug-resistant tuberculosis cases in the Northern Cape,South Africa

The Northern Cape Province has low cure rates (21%) for multidrug-resistant tuberculosis (TB). We audited the programme to identify factors affecting treatment outcomes. Cases admitted to two drug-resistant TB units from 2007 to 2009 had data extracted from clinical folders. Unfavourable treatment outcomes were found in 58% of the 272 cases. A multivariable regression analysis found that male sex was associated with unfavourable outcome (P = 0.009). Weight at diagnosis (P < 0.001) and oral drug adherence (P < 0.001) were also associated with an unfavourable outcome; however, injectable drug adherence was not (P = 0.395). Positive baseline smear and human immunodeficiency virus positive status were not associated with unfavourable outcome. Shorter, more patient-friendly regimens may go a long way to improving adherence and outcomes.